Filigrane/indice/espace réservé TextBox
Comment puis-je mettre du texte dans une zone de texte qui est automatiquement supprimée lorsque l'utilisateur tape quelque chose? (En WPF)
Voici un exemple qui montre comment créer une zone de texte en filigrane dans WPF:
<Window x:Class="WaterMarkTextBoxDemo.Window1"
xmlns="http://schemas.Microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.Microsoft.com/winfx/2006/xaml"
xmlns:local="clr-namespace:WaterMarkTextBoxDemo"
Height="200" Width="400">
<Window.Resources>
<SolidColorBrush x:Key="brushWatermarkBackground" Color="White" />
<SolidColorBrush x:Key="brushWatermarkForeground" Color="LightSteelBlue" />
<SolidColorBrush x:Key="brushWatermarkBorder" Color="Indigo" />
<BooleanToVisibilityConverter x:Key="BooleanToVisibilityConverter" />
<local:TextInputToVisibilityConverter x:Key="TextInputToVisibilityConverter" />
<Style x:Key="EntryFieldStyle" TargetType="Grid" >
<Setter Property="HorizontalAlignment" Value="Stretch" />
<Setter Property="VerticalAlignment" Value="Center" />
<Setter Property="Margin" Value="20,0" />
</Style>
</Window.Resources>
<Grid Background="LightBlue">
<Grid.RowDefinitions>
<RowDefinition />
<RowDefinition />
<RowDefinition />
</Grid.RowDefinitions>
<Grid Grid.Row="0" Background="{StaticResource brushWatermarkBackground}" Style="{StaticResource EntryFieldStyle}" >
<TextBlock Margin="5,2" Text="This Prompt dissappears as you type..." Foreground="{StaticResource brushWatermarkForeground}"
Visibility="{Binding ElementName=txtUserEntry, Path=Text.IsEmpty, Converter={StaticResource BooleanToVisibilityConverter}}" />
<TextBox Name="txtUserEntry" Background="Transparent" BorderBrush="{StaticResource brushWatermarkBorder}" />
</Grid>
<Grid Grid.Row="1" Background="{StaticResource brushWatermarkBackground}" Style="{StaticResource EntryFieldStyle}" >
<TextBlock Margin="5,2" Text="This dissappears as the control gets focus..." Foreground="{StaticResource brushWatermarkForeground}" >
<TextBlock.Visibility>
<MultiBinding Converter="{StaticResource TextInputToVisibilityConverter}">
<Binding ElementName="txtUserEntry2" Path="Text.IsEmpty" />
<Binding ElementName="txtUserEntry2" Path="IsFocused" />
</MultiBinding>
</TextBlock.Visibility>
</TextBlock>
<TextBox Name="txtUserEntry2" Background="Transparent" BorderBrush="{StaticResource brushWatermarkBorder}" />
</Grid>
</Grid>
</Window>
TextInputToVisibilityConverter est défini comme:
using System;
using System.Windows.Data;
using System.Windows;
namespace WaterMarkTextBoxDemo
{
public class TextInputToVisibilityConverter : IMultiValueConverter
{
public object Convert( object[] values, Type targetType, object parameter, System.Globalization.CultureInfo culture )
{
// Always test MultiValueConverter inputs for non-null
// (to avoid crash bugs for views in the designer)
if (values[0] is bool && values[1] is bool)
{
bool hasText = !(bool)values[0];
bool hasFocus = (bool)values[1];
if (hasFocus || hasText)
return Visibility.Collapsed;
}
return Visibility.Visible;
}
public object[] ConvertBack( object value, Type[] targetTypes, object parameter, System.Globalization.CultureInfo culture )
{
throw new NotImplementedException();
}
}
}
Note: Ce n'est pas mon code. Je l'ai trouvé ici , mais je pense que c'est la meilleure approche.
Vous pouvez créer un filigrane pouvant être ajouté à toute TextBox avec une propriété jointe. Voici la source de la propriété attachée:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Controls.Primitives;
using System.Windows.Documents;
/// <summary>
/// Class that provides the Watermark attached property
/// </summary>
public static class WatermarkService
{
/// <summary>
/// Watermark Attached Dependency Property
/// </summary>
public static readonly DependencyProperty WatermarkProperty = DependencyProperty.RegisterAttached(
"Watermark",
typeof(object),
typeof(WatermarkService),
new FrameworkPropertyMetadata((object)null, new PropertyChangedCallback(OnWatermarkChanged)));
#region Private Fields
/// <summary>
/// Dictionary of ItemsControls
/// </summary>
private static readonly Dictionary<object, ItemsControl> itemsControls = new Dictionary<object, ItemsControl>();
#endregion
/// <summary>
/// Gets the Watermark property. This dependency property indicates the watermark for the control.
/// </summary>
/// <param name="d"><see cref="DependencyObject"/> to get the property from</param>
/// <returns>The value of the Watermark property</returns>
public static object GetWatermark(DependencyObject d)
{
return (object)d.GetValue(WatermarkProperty);
}
/// <summary>
/// Sets the Watermark property. This dependency property indicates the watermark for the control.
/// </summary>
/// <param name="d"><see cref="DependencyObject"/> to set the property on</param>
/// <param name="value">value of the property</param>
public static void SetWatermark(DependencyObject d, object value)
{
d.SetValue(WatermarkProperty, value);
}
/// <summary>
/// Handles changes to the Watermark property.
/// </summary>
/// <param name="d"><see cref="DependencyObject"/> that fired the event</param>
/// <param name="e">A <see cref="DependencyPropertyChangedEventArgs"/> that contains the event data.</param>
private static void OnWatermarkChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
Control control = (Control)d;
control.Loaded += Control_Loaded;
if (d is ComboBox)
{
control.GotKeyboardFocus += Control_GotKeyboardFocus;
control.LostKeyboardFocus += Control_Loaded;
}
else if (d is TextBox)
{
control.GotKeyboardFocus += Control_GotKeyboardFocus;
control.LostKeyboardFocus += Control_Loaded;
((TextBox)control).TextChanged += Control_GotKeyboardFocus;
}
if (d is ItemsControl && !(d is ComboBox))
{
ItemsControl i = (ItemsControl)d;
// for Items property
i.ItemContainerGenerator.ItemsChanged += ItemsChanged;
itemsControls.Add(i.ItemContainerGenerator, i);
// for ItemsSource property
DependencyPropertyDescriptor prop = DependencyPropertyDescriptor.FromProperty(ItemsControl.ItemsSourceProperty, i.GetType());
prop.AddValueChanged(i, ItemsSourceChanged);
}
}
#region Event Handlers
/// <summary>
/// Handle the GotFocus event on the control
/// </summary>
/// <param name="sender">The source of the event.</param>
/// <param name="e">A <see cref="RoutedEventArgs"/> that contains the event data.</param>
private static void Control_GotKeyboardFocus(object sender, RoutedEventArgs e)
{
Control c = (Control)sender;
if (ShouldShowWatermark(c))
{
ShowWatermark(c);
}
else
{
RemoveWatermark(c);
}
}
/// <summary>
/// Handle the Loaded and LostFocus event on the control
/// </summary>
/// <param name="sender">The source of the event.</param>
/// <param name="e">A <see cref="RoutedEventArgs"/> that contains the event data.</param>
private static void Control_Loaded(object sender, RoutedEventArgs e)
{
Control control = (Control)sender;
if (ShouldShowWatermark(control))
{
ShowWatermark(control);
}
}
/// <summary>
/// Event handler for the items source changed event
/// </summary>
/// <param name="sender">The source of the event.</param>
/// <param name="e">A <see cref="EventArgs"/> that contains the event data.</param>
private static void ItemsSourceChanged(object sender, EventArgs e)
{
ItemsControl c = (ItemsControl)sender;
if (c.ItemsSource != null)
{
if (ShouldShowWatermark(c))
{
ShowWatermark(c);
}
else
{
RemoveWatermark(c);
}
}
else
{
ShowWatermark(c);
}
}
/// <summary>
/// Event handler for the items changed event
/// </summary>
/// <param name="sender">The source of the event.</param>
/// <param name="e">A <see cref="ItemsChangedEventArgs"/> that contains the event data.</param>
private static void ItemsChanged(object sender, ItemsChangedEventArgs e)
{
ItemsControl control;
if (itemsControls.TryGetValue(sender, out control))
{
if (ShouldShowWatermark(control))
{
ShowWatermark(control);
}
else
{
RemoveWatermark(control);
}
}
}
#endregion
#region Helper Methods
/// <summary>
/// Remove the watermark from the specified element
/// </summary>
/// <param name="control">Element to remove the watermark from</param>
private static void RemoveWatermark(UIElement control)
{
AdornerLayer layer = AdornerLayer.GetAdornerLayer(control);
// layer could be null if control is no longer in the visual tree
if (layer != null)
{
Adorner[] adorners = layer.GetAdorners(control);
if (adorners == null)
{
return;
}
foreach (Adorner adorner in adorners)
{
if (adorner is WatermarkAdorner)
{
adorner.Visibility = Visibility.Hidden;
layer.Remove(adorner);
}
}
}
}
/// <summary>
/// Show the watermark on the specified control
/// </summary>
/// <param name="control">Control to show the watermark on</param>
private static void ShowWatermark(Control control)
{
AdornerLayer layer = AdornerLayer.GetAdornerLayer(control);
// layer could be null if control is no longer in the visual tree
if (layer != null)
{
layer.Add(new WatermarkAdorner(control, GetWatermark(control)));
}
}
/// <summary>
/// Indicates whether or not the watermark should be shown on the specified control
/// </summary>
/// <param name="c"><see cref="Control"/> to test</param>
/// <returns>true if the watermark should be shown; false otherwise</returns>
private static bool ShouldShowWatermark(Control c)
{
if (c is ComboBox)
{
return (c as ComboBox).Text == string.Empty;
}
else if (c is TextBoxBase)
{
return (c as TextBox).Text == string.Empty;
}
else if (c is ItemsControl)
{
return (c as ItemsControl).Items.Count == 0;
}
else
{
return false;
}
}
#endregion
}
La propriété attachée utilise une classe appelée WatermarkAdorner, voici la source:
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Media;
/// <summary>
/// Adorner for the watermark
/// </summary>
internal class WatermarkAdorner : Adorner
{
#region Private Fields
/// <summary>
/// <see cref="ContentPresenter"/> that holds the watermark
/// </summary>
private readonly ContentPresenter contentPresenter;
#endregion
#region Constructor
/// <summary>
/// Initializes a new instance of the <see cref="WatermarkAdorner"/> class
/// </summary>
/// <param name="adornedElement"><see cref="UIElement"/> to be adorned</param>
/// <param name="watermark">The watermark</param>
public WatermarkAdorner(UIElement adornedElement, object watermark) :
base(adornedElement)
{
this.IsHitTestVisible = false;
this.contentPresenter = new ContentPresenter();
this.contentPresenter.Content = watermark;
this.contentPresenter.Opacity = 0.5;
this.contentPresenter.Margin = new Thickness(Control.Margin.Left + Control.Padding.Left, Control.Margin.Top + Control.Padding.Top, 0, 0);
if (this.Control is ItemsControl && !(this.Control is ComboBox))
{
this.contentPresenter.VerticalAlignment = VerticalAlignment.Center;
this.contentPresenter.HorizontalAlignment = HorizontalAlignment.Center;
}
// Hide the control adorner when the adorned element is hidden
Binding binding = new Binding("IsVisible");
binding.Source = adornedElement;
binding.Converter = new BooleanToVisibilityConverter();
this.SetBinding(VisibilityProperty, binding);
}
#endregion
#region Protected Properties
/// <summary>
/// Gets the number of children for the <see cref="ContainerVisual"/>.
/// </summary>
protected override int VisualChildrenCount
{
get { return 1; }
}
#endregion
#region Private Properties
/// <summary>
/// Gets the control that is being adorned
/// </summary>
private Control Control
{
get { return (Control)this.AdornedElement; }
}
#endregion
#region Protected Overrides
/// <summary>
/// Returns a specified child <see cref="Visual"/> for the parent <see cref="ContainerVisual"/>.
/// </summary>
/// <param name="index">A 32-bit signed integer that represents the index value of the child <see cref="Visual"/>. The value of index must be between 0 and <see cref="VisualChildrenCount"/> - 1.</param>
/// <returns>The child <see cref="Visual"/>.</returns>
protected override Visual GetVisualChild(int index)
{
return this.contentPresenter;
}
/// <summary>
/// Implements any custom measuring behavior for the adorner.
/// </summary>
/// <param name="constraint">A size to constrain the adorner to.</param>
/// <returns>A <see cref="Size"/> object representing the amount of layout space needed by the adorner.</returns>
protected override Size MeasureOverride(Size constraint)
{
// Here's the secret to getting the adorner to cover the whole control
this.contentPresenter.Measure(Control.RenderSize);
return Control.RenderSize;
}
/// <summary>
/// When overridden in a derived class, positions child elements and determines a size for a <see cref="FrameworkElement"/> derived class.
/// </summary>
/// <param name="finalSize">The final area within the parent that this element should use to arrange itself and its children.</param>
/// <returns>The actual size used.</returns>
protected override Size ArrangeOverride(Size finalSize)
{
this.contentPresenter.Arrange(new Rect(finalSize));
return finalSize;
}
#endregion
}
Maintenant, vous pouvez mettre un filigrane sur n'importe quelle zone de texte comme celle-ci:
<AdornerDecorator>
<TextBox x:Name="SearchTextBox">
<controls:WatermarkService.Watermark>
<TextBlock>Type here to search text</TextBlock>
</controls:WatermarkService.Watermark>
</TextBox>
</AdornerDecorator>
Le filigrane peut être ce que vous voulez (texte, images ...). En plus de fonctionner pour les TextBox, ce filigrane fonctionne également pour les ComboBox et les ItemControls.
Ce code a été adapté de cet article de blog .
En utilisant simplement XAML, pas d'extensions, pas de convertisseurs:
<Grid>
<TextBox Width="250" VerticalAlignment="Center" HorizontalAlignment="Left" x:Name="SearchTermTextBox" Margin="5"/>
<TextBlock IsHitTestVisible="False" Text="Enter Search Term Here" VerticalAlignment="Center" HorizontalAlignment="Left" Margin="10,0,0,0" Foreground="DarkGray">
<TextBlock.Style>
<Style TargetType="{x:Type TextBlock}">
<Setter Property="Visibility" Value="Collapsed"/>
<Style.Triggers>
<DataTrigger Binding="{Binding Text, ElementName=SearchTermTextBox}" Value="">
<Setter Property="Visibility" Value="Visible"/>
</DataTrigger>
</Style.Triggers>
</Style>
</TextBlock.Style>
</TextBlock>
</Grid>
Je ne peux pas croire que personne n'ait posté l'évidence Extended WPF Toolkit - WatermarkTextBox de Xceed. Cela fonctionne assez bien et est open source si vous souhaitez personnaliser.
Il y a un article sur CodeProject sur la façon de le faire dans "3 lignes de XAML".
<Grid Background="{StaticResource brushWatermarkBackground}">
<TextBlock Margin="5,2" Text="Type something..."
Foreground="{StaticResource brushForeground}"
Visibility="{Binding ElementName=txtUserEntry, Path=Text.IsEmpty,
Converter={StaticResource BooleanToVisibilityConverter}}" />
<TextBox Name="txtUserEntry" Background="Transparent"
BorderBrush="{StaticResource brushBorder}" />
</Grid>
Ok, eh bien, il ne s’agit peut-être pas de 3 lignes de format XAML, mais est plutôt simple.
Une chose à noter cependant, c'est qu'il utilise une méthode d'extension non standard sur la propriété Text, appelée "IsEmpty". Vous devez l'implémenter vous-même, mais l'article ne semble pas le mentionner.
J'ai vu la solution de John Myczek , et ses commentaires sur la compatibilité de ComboBox et PasswordBox, j'ai donc amélioré la solution de John Myczek, et la voici:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Controls.Primitives;
using System.Windows.Documents;
/// <summary>
/// Class that provides the Watermark attached property
/// </summary>
public static class WatermarkService
{
/// <summary>
/// Watermark Attached Dependency Property
/// </summary>
public static readonly DependencyProperty WatermarkProperty = DependencyProperty.RegisterAttached(
"Watermark",
typeof(object),
typeof(WatermarkService),
new FrameworkPropertyMetadata((object)null, new PropertyChangedCallback(OnWatermarkChanged)));
#region Private Fields
/// <summary>
/// Dictionary of ItemsControls
/// </summary>
private static readonly Dictionary<object, ItemsControl> itemsControls = new Dictionary<object, ItemsControl>();
#endregion
/// <summary>
/// Gets the Watermark property. This dependency property indicates the watermark for the control.
/// </summary>
/// <param name="d"><see cref="DependencyObject"/> to get the property from</param>
/// <returns>The value of the Watermark property</returns>
public static object GetWatermark(DependencyObject d)
{
return (object)d.GetValue(WatermarkProperty);
}
/// <summary>
/// Sets the Watermark property. This dependency property indicates the watermark for the control.
/// </summary>
/// <param name="d"><see cref="DependencyObject"/> to set the property on</param>
/// <param name="value">value of the property</param>
public static void SetWatermark(DependencyObject d, object value)
{
d.SetValue(WatermarkProperty, value);
}
/// <summary>
/// Handles changes to the Watermark property.
/// </summary>
/// <param name="d"><see cref="DependencyObject"/> that fired the event</param>
/// <param name="e">A <see cref="DependencyPropertyChangedEventArgs"/> that contains the event data.</param>
private static void OnWatermarkChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
Control control = (Control)d;
control.Loaded += Control_Loaded;
if (d is TextBox || d is PasswordBox)
{
control.GotKeyboardFocus += Control_GotKeyboardFocus;
control.LostKeyboardFocus += Control_Loaded;
}
else if (d is ComboBox)
{
control.GotKeyboardFocus += Control_GotKeyboardFocus;
control.LostKeyboardFocus += Control_Loaded;
(d as ComboBox).SelectionChanged += new SelectionChangedEventHandler(SelectionChanged);
}
else if (d is ItemsControl)
{
ItemsControl i = (ItemsControl)d;
// for Items property
i.ItemContainerGenerator.ItemsChanged += ItemsChanged;
itemsControls.Add(i.ItemContainerGenerator, i);
// for ItemsSource property
DependencyPropertyDescriptor prop = DependencyPropertyDescriptor.FromProperty(ItemsControl.ItemsSourceProperty, i.GetType());
prop.AddValueChanged(i, ItemsSourceChanged);
}
}
/// <summary>
/// Event handler for the selection changed event
/// </summary>
/// <param name="sender">The source of the event.</param>
/// <param name="e">A <see cref="ItemsChangedEventArgs"/> that contains the event data.</param>
private static void SelectionChanged(object sender, SelectionChangedEventArgs e)
{
Control control = (Control)sender;
if (ShouldShowWatermark(control))
{
ShowWatermark(control);
}
else
{
RemoveWatermark(control);
}
}
#region Event Handlers
/// <summary>
/// Handle the GotFocus event on the control
/// </summary>
/// <param name="sender">The source of the event.</param>
/// <param name="e">A <see cref="RoutedEventArgs"/> that contains the event data.</param>
private static void Control_GotKeyboardFocus(object sender, RoutedEventArgs e)
{
Control c = (Control)sender;
if (ShouldShowWatermark(c))
{
RemoveWatermark(c);
}
}
/// <summary>
/// Handle the Loaded and LostFocus event on the control
/// </summary>
/// <param name="sender">The source of the event.</param>
/// <param name="e">A <see cref="RoutedEventArgs"/> that contains the event data.</param>
private static void Control_Loaded(object sender, RoutedEventArgs e)
{
Control control = (Control)sender;
if (ShouldShowWatermark(control))
{
ShowWatermark(control);
}
}
/// <summary>
/// Event handler for the items source changed event
/// </summary>
/// <param name="sender">The source of the event.</param>
/// <param name="e">A <see cref="EventArgs"/> that contains the event data.</param>
private static void ItemsSourceChanged(object sender, EventArgs e)
{
ItemsControl c = (ItemsControl)sender;
if (c.ItemsSource != null)
{
if (ShouldShowWatermark(c))
{
ShowWatermark(c);
}
else
{
RemoveWatermark(c);
}
}
else
{
ShowWatermark(c);
}
}
/// <summary>
/// Event handler for the items changed event
/// </summary>
/// <param name="sender">The source of the event.</param>
/// <param name="e">A <see cref="ItemsChangedEventArgs"/> that contains the event data.</param>
private static void ItemsChanged(object sender, ItemsChangedEventArgs e)
{
ItemsControl control;
if (itemsControls.TryGetValue(sender, out control))
{
if (ShouldShowWatermark(control))
{
ShowWatermark(control);
}
else
{
RemoveWatermark(control);
}
}
}
#endregion
#region Helper Methods
/// <summary>
/// Remove the watermark from the specified element
/// </summary>
/// <param name="control">Element to remove the watermark from</param>
private static void RemoveWatermark(UIElement control)
{
AdornerLayer layer = AdornerLayer.GetAdornerLayer(control);
// layer could be null if control is no longer in the visual tree
if (layer != null)
{
Adorner[] adorners = layer.GetAdorners(control);
if (adorners == null)
{
return;
}
foreach (Adorner adorner in adorners)
{
if (adorner is WatermarkAdorner)
{
adorner.Visibility = Visibility.Hidden;
layer.Remove(adorner);
}
}
}
}
/// <summary>
/// Show the watermark on the specified control
/// </summary>
/// <param name="control">Control to show the watermark on</param>
private static void ShowWatermark(Control control)
{
AdornerLayer layer = AdornerLayer.GetAdornerLayer(control);
// layer could be null if control is no longer in the visual tree
if (layer != null)
{
layer.Add(new WatermarkAdorner(control, GetWatermark(control)));
}
}
/// <summary>
/// Indicates whether or not the watermark should be shown on the specified control
/// </summary>
/// <param name="c"><see cref="Control"/> to test</param>
/// <returns>true if the watermark should be shown; false otherwise</returns>
private static bool ShouldShowWatermark(Control c)
{
if (c is ComboBox)
{
return (c as ComboBox).SelectedItem == null;
//return (c as ComboBox).Text == string.Empty;
}
else if (c is TextBoxBase)
{
return (c as TextBox).Text == string.Empty;
}
else if (c is PasswordBox)
{
return (c as PasswordBox).Password == string.Empty;
}
else if (c is ItemsControl)
{
return (c as ItemsControl).Items.Count == 0;
}
else
{
return false;
}
}
#endregion
}
Maintenant, une ComboBox peut être aussi Editable, et PasswordBox peut aussi ajouter un filigrane aussi . N'oubliez pas d'utiliser le commentaire de JoanComasFdz ci-dessus pour résoudre le problème de la marge.
Et bien sûr, tout le mérite revient à John Myczek.
Solution simple en utilisant le style:
<TextBox>
<TextBox.Style>
<Style TargetType="TextBox" xmlns:sys="clr-namespace:System;Assembly=mscorlib">
<Style.Resources>
<VisualBrush x:Key="CueBannerBrush" AlignmentX="Left" AlignmentY="Center" Stretch="None">
<VisualBrush.Visual>
<Label Content="MM:SS:HH AM/PM" Foreground="LightGray" />
</VisualBrush.Visual>
</VisualBrush>
</Style.Resources>
<Style.Triggers>
<Trigger Property="Text" Value="{x:Static sys:String.Empty}">
<Setter Property="Background" Value="{StaticResource CueBannerBrush}" />
</Trigger>
<Trigger Property="Text" Value="{x:Null}">
<Setter Property="Background" Value="{StaticResource CueBannerBrush}" />
</Trigger>
<Trigger Property="IsKeyboardFocused" Value="True">
<Setter Property="Background" Value="White" />
</Trigger>
</Style.Triggers>
</Style>
</TextBox.Style>
</TextBox>
Excellente solution:
https://code.msdn.Microsoft.com/windowsdesktop/In-place-hit-messages-for-18db3a6c
Cette bibliothèque a un filigrane.
Exemple d'utilisation:
<TextBox adorners:Watermark.Text="Write something here"
adorners:Watermark.TextStyle="{StaticResource AdornerTextStyle}"
adorners:Watermark.VisibleWhen="EmptyAndNotKeyboardFocused"/>
J'ai créé une implémentation en code unique qui fonctionne bien pour WPF et Silverlight également:
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Media;
public class TextBoxWatermarked : TextBox
{
#region [ Dependency Properties ]
public static DependencyProperty WatermarkProperty = DependencyProperty.Register("Watermark",
typeof(string),
typeof(TextBoxWatermarked),
new PropertyMetadata(new PropertyChangedCallback(OnWatermarkChanged)));
#endregion
#region [ Fields ]
private bool _isWatermarked;
private Binding _textBinding;
#endregion
#region [ Properties ]
protected new Brush Foreground
{
get { return base.Foreground; }
set { base.Foreground = value; }
}
public string Watermark
{
get { return (string)GetValue(WatermarkProperty); }
set { SetValue(WatermarkProperty, value); }
}
#endregion
#region [ .ctor ]
public TextBoxWatermarked()
{
Loaded += (s, ea) => ShowWatermark();
}
#endregion
#region [ Event Handlers ]
protected override void OnGotFocus(RoutedEventArgs e)
{
base.OnGotFocus(e);
HideWatermark();
}
protected override void OnLostFocus(RoutedEventArgs e)
{
base.OnLostFocus(e);
ShowWatermark();
}
private static void OnWatermarkChanged(DependencyObject sender, DependencyPropertyChangedEventArgs ea)
{
var tbw = sender as TextBoxWatermarked;
if (tbw == null) return;
tbw.ShowWatermark();
}
#endregion
#region [ Methods ]
private void ShowWatermark()
{
if (string.IsNullOrEmpty(base.Text))
{
_isWatermarked = true;
base.Foreground = new SolidColorBrush(Colors.Gray);
var bindingExpression = GetBindingExpression(TextProperty);
_textBinding = bindingExpression == null ? null : bindingExpression.ParentBinding;
if (bindingExpression != null)
bindingExpression.UpdateSource();
SetBinding(TextProperty, new Binding());
base.Text = Watermark;
}
}
private void HideWatermark()
{
if (_isWatermarked)
{
_isWatermarked = false;
ClearValue(ForegroundProperty);
base.Text = "";
SetBinding(TextProperty, _textBinding ?? new Binding());
}
}
#endregion
}
Usage:
<TextBoxWatermarked Watermark="Some text" />
J'ai rencontré quelques difficultés lorsque j'utilisais le code code de @ john-myczek avec une zone de texte liée. Comme la zone de texte ne déclenche pas d'événement de focus lors de la mise à jour, le filigrane reste visible sous le nouveau texte. Pour résoudre ce problème, j'ai simplement ajouté un autre gestionnaire d'événements:
if (d is ComboBox || d is TextBox)
{
control.GotKeyboardFocus += Control_GotKeyboardFocus;
control.LostKeyboardFocus += Control_Loaded;
if (d is TextBox)
(d as TextBox).TextChanged += Control_TextChanged;
}
private static void Control_TextChanged(object sender, RoutedEventArgs e)
{
var tb = (TextBox)sender;
if (ShouldShowWatermark(tb))
{
ShowWatermark(tb);
}
else
{
RemoveWatermark(tb);
}
}
@Veton - J'aime beaucoup la simplicité de votre solution, mais ma réputation n'est pas assez bonne pour vous heurter.
@Tim Murphy - Cette erreur "La liaison bidirectionnelle nécessite un chemin ou XPath" était une solution facile ... code mis à jour, y compris quelques autres petits ajustements (seulement WPF testé):
using System;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Media;
public class TextBoxWatermarked : TextBox
{
public string Watermark
{
get { return (string)GetValue(WaterMarkProperty); }
set { SetValue(WaterMarkProperty, value); }
}
public static readonly DependencyProperty WaterMarkProperty =
DependencyProperty.Register("Watermark", typeof(string), typeof(TextBoxWatermarked), new PropertyMetadata(new PropertyChangedCallback(OnWatermarkChanged)));
private bool _isWatermarked = false;
private Binding _textBinding = null;
public TextBoxWatermarked()
{
Loaded += (s, ea) => ShowWatermark();
}
protected override void OnGotFocus(RoutedEventArgs e)
{
base.OnGotFocus(e);
HideWatermark();
}
protected override void OnLostFocus(RoutedEventArgs e)
{
base.OnLostFocus(e);
ShowWatermark();
}
private static void OnWatermarkChanged(DependencyObject sender, DependencyPropertyChangedEventArgs ea)
{
var tbw = sender as TextBoxWatermarked;
if (tbw == null || !tbw.IsLoaded) return; //needed to check IsLoaded so that we didn't dive into the ShowWatermark() routine before initial Bindings had been made
tbw.ShowWatermark();
}
private void ShowWatermark()
{
if (String.IsNullOrEmpty(Text) && !String.IsNullOrEmpty(Watermark))
{
_isWatermarked = true;
//save the existing binding so it can be restored
_textBinding = BindingOperations.GetBinding(this, TextProperty);
//blank out the existing binding so we can throw in our Watermark
BindingOperations.ClearBinding(this, TextProperty);
//set the signature watermark gray
Foreground = new SolidColorBrush(Colors.Gray);
//display our watermark text
Text = Watermark;
}
}
private void HideWatermark()
{
if (_isWatermarked)
{
_isWatermarked = false;
ClearValue(ForegroundProperty);
Text = "";
if (_textBinding != null) SetBinding(TextProperty, _textBinding);
}
}
}
Configurez la zone de texte avec du texte de substitution dans une couleur douce ...
public MainWindow ( )
{
InitializeComponent ( );
txtInput.Text = "Type something here...";
txtInput.Foreground = Brushes.DimGray;
}
Lorsque la zone de texte obtient le focus, désactivez-la et changez la couleur du texte.
private void txtInput_GotFocus ( object sender, EventArgs e )
{
MessageBox.Show ( "got focus" );
txtInput.Text = "";
txtInput.Foreground = Brushes.Red;
}
MahApps.Metro pour WPF a un contrôle de filigrane intégré, si vous préférez ne pas lancer le vôtre. C'est assez simple à utiliser.
<AdornerDecorator>
<TextBox Name="txtSomeText"
Width="200"
HorizontalAlignment="Right">
<Controls:TextBoxHelper.Watermark>I'm a watermark!</Controls:TextBoxHelper.Watermark>
</TextBox>
</AdornerDecorator>
Eh bien voici le mien: pas nécessairement le meilleur, mais comme c'est simple, il est facile de le modifier à votre goût.
<UserControl x:Class="WPFControls.ShadowedTextBox"
xmlns="http://schemas.Microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.Microsoft.com/winfx/2006/xaml"
xmlns:local="clr-namespace:WPFControls"
Name="Root">
<UserControl.Resources>
<local:ShadowConverter x:Key="ShadowConvert"/>
</UserControl.Resources>
<Grid>
<TextBox Name="textBox"
Foreground="{Binding ElementName=Root, Path=Foreground}"
Text="{Binding ElementName=Root, Path=Text, UpdateSourceTrigger=PropertyChanged}"
TextChanged="textBox_TextChanged"
TextWrapping="Wrap"
VerticalContentAlignment="Center"/>
<TextBlock Name="WaterMarkLabel"
IsHitTestVisible="False"
Foreground="{Binding ElementName=Root,Path=Foreground}"
FontWeight="Thin"
Opacity=".345"
FontStyle="Italic"
Text="{Binding ElementName=Root, Path=Watermark}"
VerticalAlignment="Center"
TextWrapping="Wrap"
TextAlignment="Center">
<TextBlock.Visibility>
<MultiBinding Converter="{StaticResource ShadowConvert}">
<Binding ElementName="textBox" Path="Text"/>
</MultiBinding>
</TextBlock.Visibility>
</TextBlock>
</Grid>
Le convertisseur, comme il est écrit maintenant, n’est pas nécessaire qu’il s’agisse d’un MultiConverter, mais dans ce contexte, il peut être étendu facilement.
using System;
using System.Globalization;
using System.Windows;
using System.Windows.Data;
namespace WPFControls
{
class ShadowConverter:IMultiValueConverter
{
#region Implementation of IMultiValueConverter
public object Convert(object[] values, Type targetType, object parameter, CultureInfo culture)
{
var text = (string) values[0];
return text == string.Empty
? Visibility.Visible
: Visibility.Collapsed;
}
public object[] ConvertBack(object value, Type[] targetTypes, object parameter, CultureInfo culture)
{
return new object[0];
}
#endregion
}
}
et enfin le code derrière:
using System.Windows;
using System.Windows.Controls;
namespace WPFControls
{
/// <summary>
/// Interaction logic for ShadowedTextBox.xaml
/// </summary>
public partial class ShadowedTextBox : UserControl
{
public event TextChangedEventHandler TextChanged;
public ShadowedTextBox()
{
InitializeComponent();
}
public static readonly DependencyProperty WatermarkProperty =
DependencyProperty.Register("Watermark",
typeof (string),
typeof (ShadowedTextBox),
new UIPropertyMetadata(string.Empty));
public static readonly DependencyProperty TextProperty =
DependencyProperty.Register("Text",
typeof (string),
typeof (ShadowedTextBox),
new UIPropertyMetadata(string.Empty));
public static readonly DependencyProperty TextChangedProperty =
DependencyProperty.Register("TextChanged",
typeof (TextChangedEventHandler),
typeof (ShadowedTextBox),
new UIPropertyMetadata(null));
public string Watermark
{
get { return (string)GetValue(WatermarkProperty); }
set
{
SetValue(WatermarkProperty, value);
}
}
public string Text
{
get { return (string) GetValue(TextProperty); }
set{SetValue(TextProperty,value);}
}
private void textBox_TextChanged(object sender, TextChangedEventArgs e)
{
if (TextChanged != null) TextChanged(this, e);
}
public void Clear()
{
textBox.Clear();
}
}
}
vous pouvez utiliser les événements GetFocus() et LostFocus() pour le faire.
voici l'exemple:
private void txtData1_GetFocus(object sender, RoutedEventArgs e)
{
if (txtData1.Text == "TextBox1abc")
{
txtData1.Text = string.Empty;
}
}
private void txtData1_LostFocus(object sender, RoutedEventArgs e)
{
if (txtData1.Text == string.Empty)
{
txtData1.Text = "TextBox1abc";
}
}
<Window.Resources>
<Style x:Key="TextBoxUserStyle" BasedOn="{x:Null}" TargetType="{x:Type TextBox}">
<Setter Property="Foreground" Value="Black"/>
<Setter Property="HorizontalAlignment" Value="Center"/>
<Setter Property="VerticalContentAlignment" Value="Center"/>
<Setter Property="Width" Value="225"/>
<Setter Property="Height" Value="25"/>
<Setter Property="FontSize" Value="12"/>
<Setter Property="Padding" Value="1"/>
<Setter Property="Margin" Value="5"/>
<Setter Property="AllowDrop" Value="true"/>
<Setter Property="FocusVisualStyle" Value="{x:Null}"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type TextBox}">
<Border x:Name="OuterBorder" BorderBrush="#5AFFFFFF" BorderThickness="1,1,1,1" CornerRadius="4,4,4,4">
<Border x:Name="InnerBorder" Background="#FFFFFFFF" BorderBrush="#33000000" BorderThickness="1,1,1,1" CornerRadius="3,3,3,3">
<ScrollViewer SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" x:Name="PART_ContentHost"/>
</Border>
</Border>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
<Style x:Key="PasswordBoxVistaStyle" BasedOn="{x:Null}" TargetType="{x:Type PasswordBox}">
<Setter Property="Foreground" Value="Black"/>
<Setter Property="HorizontalAlignment" Value="Center"/>
<Setter Property="VerticalContentAlignment" Value="Center"/>
<Setter Property="Width" Value="225"/>
<Setter Property="Height" Value="25"/>
<Setter Property="FontSize" Value="12"/>
<Setter Property="Padding" Value="1"/>
<Setter Property="Margin" Value="5"/>
<Setter Property="AllowDrop" Value="true"/>
<Setter Property="FocusVisualStyle" Value="{x:Null}"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type PasswordBox}">
<Border x:Name="OuterBorder" BorderBrush="#5AFFFFFF" BorderThickness="1,1,1,1" CornerRadius="4,4,4,4">
<Border x:Name="InnerBorder" Background="#FFFFFFFF" BorderBrush="#33000000" BorderThickness="1,1,1,1" CornerRadius="3,3,3,3">
<Grid>
<Label x:Name="lblPwd" Content="Password" FontSize="11" VerticalAlignment="Center" Margin="2,0,0,0" FontFamily="Verdana" Foreground="#828385" Padding="0"/>
<ScrollViewer SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" x:Name="PART_ContentHost"/>
</Grid>
</Border>
</Border>
<ControlTemplate.Triggers>
<Trigger Property="IsFocused" Value="True">
<Setter Property="Visibility" TargetName="lblPwd" Value="Hidden"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</Window.Resources>
<PasswordBox Style="{StaticResource PasswordBoxVistaStyle}" Margin="169,143,22,0" Name="txtPassword" FontSize="14" TabIndex="2" Height="31" VerticalAlignment="Top" />
Cela peut aider à vérifier avec votre code. Lorsqu'il est appliqué à la boîte de mot de passe, il affichera le mot de passe, qui disparaîtra lorsque les types d'utilisateurs sont utilisés.
Voici la solution la plus simple:
<Grid>
<Label Content="Placeholder text" VerticalAlignment="Center" Margin="10">
<Label.Style>
<Style TargetType="Label">
<Setter Property="Foreground" Value="Transparent"/>
<Style.Triggers>
<DataTrigger Binding="{Binding Expression}" Value="">
<Setter Property="Foreground" Value="Gray"/>
</DataTrigger>
</Style.Triggers>
</Style>
</Label.Style>
</Label>
<TextBox HorizontalAlignment="Stretch" Margin="5" Background="Transparent"
Text="{Binding Expression, UpdateSourceTrigger=PropertyChanged}" VerticalAlignment="Center" Padding="5">
</TextBox>
</Grid>
Ceci est une zone de texte avec un fond transparent superposant une étiquette. Le texte gris de l'étiquette est rendu transparent par un déclencheur de données qui se déclenche dès que le texte lié est autre chose qu'une chaîne vide.
<TextBox x:Name="OrderTxt" HorizontalAlignment="Left" VerticalAlignment="Top" VerticalContentAlignment="Center" Margin="10,10,0,0" Width="188" Height="32"/>
<Label IsHitTestVisible="False" Content="Order number" DataContext="{Binding ElementName=OrderTxt}" Foreground="DarkGray">
<Label.Style>
<Style TargetType="{x:Type Label}">
<Setter Property="Visibility" Value="Collapsed"/>
<Setter Property="Width" Value="{Binding Width}"/>
<Setter Property="Height" Value="{Binding Height}"/>
<Setter Property="Margin" Value="{Binding Margin}"/>
<Setter Property="VerticalAlignment" Value="{Binding VerticalAlignment}"/>
<Setter Property="HorizontalAlignment" Value="{Binding HorizontalAlignment}"/>
<Setter Property="VerticalContentAlignment" Value="{Binding VerticalContentAlignment}"/>
<Style.Triggers>
<DataTrigger Binding="{Binding Text}" Value="">
<Setter Property="Visibility" Value="Visible"/>
</DataTrigger>
</Style.Triggers>
</Style>
</Label.Style>
</Label>
Regardez une autre solution simple:
Je suis concentré sur les événements GotFocus et LostFocus.
XAML:
<Grid>
<TextBlock x:Name="DosyaİhtivaEdenDizinYansıması" Text="Hedef Dizin Belirtin" VerticalAlignment="Center" HorizontalAlignment="Center" TextAlignment="Center" Foreground="White" Background="Transparent" Width="500" MinWidth="300" Margin="10,0,0,0" Opacity="0.7"/>
<TextBox x:Name="DosyaİhtivaEdenDizin" CaretBrush="White" Foreground="White" Background="Transparent" VerticalContentAlignment="Center" HorizontalContentAlignment="Center" VerticalAlignment="Center" HorizontalAlignment="Center" MinHeight="40" BorderThickness="1" BorderBrush="White" Width="500" MinWidth="300" Margin="10,0,0,0" GotFocus="DosyaİhtivaEdenDizin_GotFocus" LostFocus="DosyaİhtivaEdenDizin_LostFocus"/>
</Grid>
C #:
#region DosyaİhtivaEdenDizin
private void DosyaİhtivaEdenDizin_GotFocus(object sender, RoutedEventArgs e)
{
if (DosyaİhtivaEdenDizin.Text.Length == 0)
{
DosyaİhtivaEdenDizinYansıması.Text = "";
}
}
private void DosyaİhtivaEdenDizin_LostFocus(object sender, RoutedEventArgs e)
{
if (DosyaİhtivaEdenDizin.Text.Length == 0)
{
DosyaİhtivaEdenDizinYansıması.Text = "Hedef Dizin Belirtin";
}
}
#endregion
Voici mon approche. Idéal pour MVVM, où je vérifie également si la zone de texte a le focus. Vous pouvez également utiliser un déclencheur normal uniquement pour la valeur du texte. Il suffit de changer l'image d'arrière-plan lorsque la valeur change:
<TextBox.Style>
<Style TargetType="TextBox">
<Style.Triggers>
<MultiTrigger>
<MultiTrigger.Conditions>
<Condition Property="IsFocused" Value="True"/>
<Condition Property="Text" Value=""/>
</MultiTrigger.Conditions>
<MultiTrigger.Setters>
<Setter Property="Background">
<Setter.Value>
<ImageBrush ImageSource="/Images/Scan.PNG" Stretch="Uniform" AlignmentX="Left"/>
</Setter.Value>
</Setter>
</MultiTrigger.Setters>
</MultiTrigger>
</Style.Triggers>
</Style>
</TextBox.Style>
</TextBox>
J'ai décidé de résoudre ce problème via un comportement. Il utilise une propriété Hint pour définir le texte à afficher (peut également être un objet, si vous préférez) et une propriété Value pour évaluer si l'indicateur doit être visible ou non.
Le comportement est déclaré comme suit:
using System;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Interactivity;
using System.Windows.Media;
public class HintBehavior : Behavior<ContentControl>
{
public static readonly DependencyProperty HintProperty = DependencyProperty
.Register("Hint", typeof (string), typeof (HintBehavior)
//, new FrameworkPropertyMetadata(null, OnHintChanged)
);
public string Hint
{
get { return (string) GetValue(HintProperty); }
set { SetValue(HintProperty, value); }
}
public static readonly DependencyProperty ValueProperty = DependencyProperty
.Register("Value", typeof (object), typeof (HintBehavior)
, new FrameworkPropertyMetadata(null, OnValueChanged));
private static void OnValueChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
var visible = e.NewValue == null;
d.SetValue(VisibilityProperty, visible ? Visibility.Visible : Visibility.Collapsed);
}
public object Value
{
get { return GetValue(ValueProperty); }
set { SetValue(ValueProperty, value); }
}
public static readonly DependencyProperty VisibilityProperty = DependencyProperty
.Register("Visibility", typeof (Visibility), typeof (HintBehavior)
, new FrameworkPropertyMetadata(Visibility.Visible
//, new PropertyChangedCallback(OnVisibilityChanged)
));
public Visibility Visibility
{
get { return (Visibility) GetValue(VisibilityProperty); }
set { SetValue(VisibilityProperty, value); }
}
public static readonly DependencyProperty ForegroundProperty = DependencyProperty
.Register("Foreground", typeof (Brush), typeof (HintBehavior)
, new FrameworkPropertyMetadata(new SolidColorBrush(Colors.DarkGray)
//, new PropertyChangedCallback(OnForegroundChanged)
));
public Brush Foreground
{
get { return (Brush) GetValue(ForegroundProperty); }
set { SetValue(ForegroundProperty, value); }
}
public static readonly DependencyProperty MarginProperty = DependencyProperty
.Register("Margin", typeof (Thickness), typeof (HintBehavior)
, new FrameworkPropertyMetadata(new Thickness(4, 5, 0, 0)
//, new PropertyChangedCallback(OnMarginChanged)
));
public Thickness Margin
{
get { return (Thickness) GetValue(MarginProperty); }
set { SetValue(MarginProperty, value); }
}
private static ResourceDictionary _hintBehaviorResources;
public static ResourceDictionary HintBehaviorResources
{
get
{
if (_hintBehaviorResources == null)
{
var res = new ResourceDictionary
{
Source = new Uri("/Mayflower.Client.Core;component/Behaviors/HintBehaviorResources.xaml",
UriKind.RelativeOrAbsolute)
};
_hintBehaviorResources = res;
}
return _hintBehaviorResources;
}
}
protected override void OnAttached()
{
base.OnAttached();
var t = (ControlTemplate) HintBehaviorResources["HintBehaviorWrapper"];
AssociatedObject.Template = t;
AssociatedObject.Loaded += OnLoaded;
}
private void OnLoaded(object sender, RoutedEventArgs e)
{
AssociatedObject.Loaded -= OnLoaded;
var label = (Label) AssociatedObject.Template.FindName("PART_HintLabel", AssociatedObject);
label.DataContext = this;
//label.Content = "Hello...";
label.SetBinding(UIElement.VisibilityProperty, new Binding("Visibility") {Source = this, Mode = BindingMode.OneWay});
label.SetBinding(ContentControl.ContentProperty, new Binding("Hint") {Source = this, Mode = BindingMode.OneWay});
label.SetBinding(Control.ForegroundProperty, new Binding("Foreground") {Source = this, Mode = BindingMode.OneWay});
label.SetBinding(FrameworkElement.MarginProperty, new Binding("Margin") {Source = this, Mode = BindingMode.OneWay});
}
}
Il enveloppe la cible avec son propre modèle, en y ajoutant une étiquette:
<ResourceDictionary xmlns="http://schemas.Microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.Microsoft.com/winfx/2006/xaml">
<ControlTemplate x:Key="HintBehaviorWrapper" TargetType="{x:Type ContentControl}">
<Grid>
<ContentPresenter Content="{TemplateBinding Content}" />
<Label x:Name="PART_HintLabel" IsHitTestVisible="False" Padding="0" />
</Grid>
</ControlTemplate>
</ResourceDictionary>
Pour l'utiliser, il suffit de l'ajouter en tant que comportement et de lier vos valeurs (dans mon cas, je l'ajoute dans un ControlTemplate, d'où la liaison):
<ContentControl>
<i:Interaction.Behaviors>
<behaviors:HintBehavior Value="{Binding Property, RelativeSource={RelativeSource TemplatedParent}}"
Hint="{Binding Hint, RelativeSource={RelativeSource TemplatedParent}}" />
</i:Interaction.Behaviors>
<TextBox ... />
</ContentControl>
J'aimerais des commentaires si cela est considéré comme une solution propre. Il ne nécessite pas de dictionnaires statiques et n'a donc aucune fuite de mémoire.
Voir aussi réponse . Vous pouvez accomplir ceci beaucoup plus facilement avec un VisualBrush et des déclencheurs dans un Style:
<TextBox>
<TextBox.Style>
<Style TargetType="TextBox" xmlns:sys="clr-namespace:System;Assembly=mscorlib">
<Style.Resources>
<VisualBrush x:Key="CueBannerBrush" AlignmentX="Left" AlignmentY="Center" Stretch="None">
<VisualBrush.Visual>
<Label Content="Search" Foreground="LightGray" />
</VisualBrush.Visual>
</VisualBrush>
</Style.Resources>
<Style.Triggers>
<Trigger Property="Text" Value="{x:Static sys:String.Empty}">
<Setter Property="Background" Value="{StaticResource CueBannerBrush}" />
</Trigger>
<Trigger Property="Text" Value="{x:Null}">
<Setter Property="Background" Value="{StaticResource CueBannerBrush}" />
</Trigger>
<Trigger Property="IsKeyboardFocused" Value="True">
<Setter Property="Background" Value="White" />
</Trigger>
</Style.Triggers>
</Style>
</TextBox.Style>
</TextBox>
Pour augmenter la possibilité de réutilisation de ce style, vous pouvez également créer un ensemble de propriétés attachées pour contrôler le texte, la couleur, l’orientation, etc., de la bannière de repère.
salut, j'ai mis cette tâche dans un comportement. il vous suffit d'ajouter quelque chose comme ceci à votre zone de texte
<i:Interaction.Behaviors>
<Behaviors:TextBoxWatermarkBehavior Label="Test Watermark" LabelStyle="{StaticResource StyleWatermarkLabel}"/>
</i:Interaction.Behaviors>
vous pouvez trouver mon blog ici
J'ai trouvé cette façon de le faire très rapidement et facilement
<ComboBox x:Name="comboBox1" SelectedIndex="0" HorizontalAlignment="Left" Margin="202,43,0,0" VerticalAlignment="Top" Width="149">
<ComboBoxItem Visibility="Collapsed">
<TextBlock Foreground="Gray" FontStyle="Italic">Please select ...</TextBlock>
</ComboBoxItem>
<ComboBoxItem Name="cbiFirst1">First Item</ComboBoxItem>
<ComboBoxItem Name="cbiSecond1">Second Item</ComboBoxItem>
<ComboBoxItem Name="cbiThird1">third Item</ComboBoxItem>
</ComboBox>
Peut-être que cela peut aider ceux qui essaient de le faire
Source: http://www.admindiaries.com/displaying-a-please-select-watermark-type-text-in-a-wpf-combobox/
Si, au lieu que la visibilité du filigrane dépende de l'état du focus du contrôle, vous voulez que cela dépende du fait que l'utilisateur ait saisi du texte ou non, vous pouvez mettre à jour la réponse de John Myczek (de OnWatermarkChanged bas) à
static void OnWatermarkChanged(DependencyObject d, DependencyPropertyChangedEventArgs e) {
var textbox = (TextBox)d;
textbox.Loaded += UpdateWatermark;
textbox.TextChanged += UpdateWatermark;
}
static void UpdateWatermark(object sender, RoutedEventArgs e) {
var textbox = (TextBox)sender;
var layer = AdornerLayer.GetAdornerLayer(textbox);
if (layer != null) {
if (textbox.Text == string.Empty) {
layer.Add(new WatermarkAdorner(textbox, GetWatermark(textbox)));
} else {
var adorners = layer.GetAdorners(textbox);
if (adorners == null) {
return;
}
foreach (var adorner in adorners) {
if (adorner is WatermarkAdorner) {
adorner.Visibility = Visibility.Hidden;
layer.Remove(adorner);
}
}
}
}
}
Cela a plus de sens si votre zone de texte est automatiquement activée lors de l'affichage du formulaire ou lors de la liaison de données à la propriété Text.
De même, si votre filigrane est toujours juste une chaîne et que vous avez besoin que le style du filigrane corresponde à celui de la zone de texte, procédez comme suit dans l'Adorner:
contentPresenter = new ContentPresenter {
Content = new TextBlock {
Text = (string)watermark,
Foreground = Control.Foreground,
Background = Control.Background,
FontFamily = Control.FontFamily,
FontSize = Control.FontSize,
...
},
...
}
Ma solution est assez simple.
Dans ma fenêtre de connexion. le xaml est comme ça.
<DockPanel HorizontalAlignment="Center" VerticalAlignment="Center" Height="80" Width="300" LastChildFill="True">
<Button Margin="5,0,0,0" Click="login_Click" DockPanel.Dock="Right" VerticalAlignment="Center" ToolTip="Login to system">
Login
</Button>
<StackPanel>
<TextBox x:Name="userNameWatermarked" Height="25" Foreground="Gray" Text="UserName" GotFocus="userNameWatermarked_GotFocus"></TextBox>
<TextBox x:Name="userName" Height="25" TextChanged="loginElement_TextChanged" Visibility="Collapsed" LostFocus="userName_LostFocus" ></TextBox>
<TextBox x:Name="passwordWatermarked" Height="25" Foreground="Gray" Text="Password" Margin="0,5,0,5" GotFocus="passwordWatermarked_GotFocus"></TextBox>
<PasswordBox x:Name="password" Height="25" PasswordChanged="password_PasswordChanged" KeyUp="password_KeyUp" LostFocus="password_LostFocus" Margin="0,5,0,5" Visibility="Collapsed"></PasswordBox>
<TextBlock x:Name="loginError" Visibility="Hidden" Foreground="Red" FontSize="12"></TextBlock>
</StackPanel>
</DockPanel>
le code est comme ça.
private void userNameWatermarked_GotFocus(object sender, RoutedEventArgs e)
{
userNameWatermarked.Visibility = System.Windows.Visibility.Collapsed;
userName.Visibility = System.Windows.Visibility.Visible;
userName.Focus();
}
private void userName_LostFocus(object sender, RoutedEventArgs e)
{
if (string.IsNullOrEmpty(this.userName.Text))
{
userName.Visibility = System.Windows.Visibility.Collapsed;
userNameWatermarked.Visibility = System.Windows.Visibility.Visible;
}
}
private void passwordWatermarked_GotFocus(object sender, RoutedEventArgs e)
{
passwordWatermarked.Visibility = System.Windows.Visibility.Collapsed;
password.Visibility = System.Windows.Visibility.Visible;
password.Focus();
}
private void password_LostFocus(object sender, RoutedEventArgs e)
{
if (string.IsNullOrEmpty(this.password.Password))
{
password.Visibility = System.Windows.Visibility.Collapsed;
passwordWatermarked.Visibility = System.Windows.Visibility.Visible;
}
}
Il suffit de décider de masquer ou d'afficher la zone de texte en filigrane. Bien que pas beau, mais fonctionne bien.
Cette technique utilise la propriété Background pour afficher/masquer la zone de texte d'espace réservé.
Placeholder est affiché événement lorsque Textbox a le focus
Comment ça marche:
- Lorsqu'il est vide, l'arrière-plan de la zone de texte est défini sur Transparent pour afficher du texte PlaceHolder.
- Lorsque l’arrière-plan n’est pas vide, définissez-le sur Blanc pour masquer le texte PlaceHolder.
Voici un exemple de base. Pour mes propres besoins, j'ai transformé cela en un UserControl.
<Grid>
<Grid.Resources>
<ux:NotEmptyConverter x:Key="NotEmptyConverter" />
<Style TargetType="{x:Type Control}" x:Key="DefaultStyle">
<Setter Property="FontSize" Value="20" />
<Setter Property="Margin" Value="10"/>
<Setter Property="VerticalAlignment" Value="Center"></Setter>
<Setter Property="VerticalContentAlignment" Value="Center"></Setter>
</Style>
<Style TargetType="{x:Type TextBox}" BasedOn="{StaticResource DefaultStyle}"></Style>
</Grid.Resources>
<Grid.RowDefinitions>
<RowDefinition Height="Auto"/>
</Grid.RowDefinitions>
<TextBox Grid.Row="0" Text="Placeholder Text Is Here" Foreground="DarkGray" />
<TextBox Grid.Row="0" Name="TextBoxEdit"
Text="{Binding Path=FirstName, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" >
<TextBox.Style>
<Style TargetType="{x:Type TextBox}" BasedOn="{StaticResource DefaultStyle}">
<Style.Triggers>
<DataTrigger Binding="{Binding Path=FirstName.Length, FallbackValue=0, TargetNullValue=0}" Value="0">
<Setter Property="Background" Value="Transparent"/>
</DataTrigger>
<DataTrigger Binding="{Binding Path=FirstName, FallbackValue=0, TargetNullValue=0, Converter={StaticResource NotEmptyConverter}}" Value="false">
<Setter Property="Background" Value="White"/>
</DataTrigger>
</Style.Triggers>
</Style>
</TextBox.Style>
</TextBox>
</Grid>
Voici ValueConverter pour détecter les chaînes non vides dans le DataTrigger.
public class NotEmptyConverter : IValueConverter
{
public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
{
var s = value as string;
return string.IsNullOrEmpty(s);
}
public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
{
return null;
}
}
Vous pouvez conserver une valeur distincte pour le texte saisi et la définir avec le champ "Texte" de la zone de texte dans les événements "GotFocus" et "LostFocus". Lorsque vous obtenez le focus, vous voudrez effacer la zone de texte s'il n'y a pas de valeur. Et lorsque vous perdez le focus, vous voudrez peut-être définir la valeur "Text" dans la zone de texte, puis la valeur "Text" de la zone de texte si elle est vide.
private String username = "";
private void usernameTextBox_GotFocus(object sender, RoutedEventArgs e) {
if (String.IsNullOrEmpty(username)) {
usernameTextBox.Text = "";
}
}
private void usernameTextBox_LostFocus(object sender, RoutedEventArgs e) {
username = usernameTextBox.Text;
if (String.IsNullOrEmpty(usernameTextBox.Text)) {
usernameTextBox.Text = "Username";
}
}
Ensuite, vous devez simplement vous assurer que la valeur "Texte" de la zone de texte est initialisée avec le texte de l'espace réservé.
<TextBox x:Name="usernameTextBox" Text="Username" GotFocus="usernameTextBox_GotFocus" LostFocus="usernameTextBox_LostFocus" />
Vous pouvez ensuite extraire cela dans une classe qui étend la classe "TextBox", puis le réutiliser dans votre projet.
namespace UI {
public class PlaceholderTextBox : TextBox {
public String Value { get; set; }
public String PlaceholderText { get; set; }
public Brush PlaceholderBrush { get; set; }
private Brush ValuedBrush { get; set; }
public PlaceholderTextBox() : base() {}
protected override void OnInitialized(EventArgs e) {
base.OnInitialized(e);
ValuedBrush = this.Foreground;
if (String.IsNullOrEmpty(this.Text)) {
this.Text = PlaceholderText;
this.Foreground = PlaceholderBrush;
}
}
protected override void OnGotFocus(System.Windows.RoutedEventArgs e) {
this.Foreground = ValuedBrush;
if (String.IsNullOrEmpty(Value)) {
this.Text = "";
}
base.OnGotFocus(e);
}
protected override void OnLostFocus(System.Windows.RoutedEventArgs e) {
Value = this.Text;
if (String.IsNullOrEmpty(this.Text)) {
this.Text = PlaceholderText;
this.Foreground = PlaceholderBrush;
}
base.OnLostFocus(e);
}
}
}
Et puis cela peut être ajouté directement dans le xaml.
<Window x:Class="UI.LoginWindow"
xmlns="http://schemas.Microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.Microsoft.com/winfx/2006/xaml"
xmlns:m="clr-namespace:UI"
Initialized="Window_Initialized">
<Grid>
<m:PlaceholderTextBox x:Name="usernameTextBox" PlaceholderText="Username" PlaceholderBrush="Gray" />
</Grid>
</Window>
namespace PlaceholderForRichTexxBoxInWPF
{
public MainWindow()
{
InitializeComponent();
Application.Current.MainWindow.WindowState = WindowState.Maximized;// maximize window on load
richTextBox1.GotKeyboardFocus += new KeyboardFocusChangedEventHandler(rtb_GotKeyboardFocus);
richTextBox1.LostKeyboardFocus += new KeyboardFocusChangedEventHandler(rtb_LostKeyboardFocus);
richTextBox1.AppendText("Place Holder");
richTextBox1.Foreground = Brushes.Gray;
}
private void rtb_GotKeyboardFocus(object sender, KeyboardFocusChangedEventArgs e)
{
if (sender is RichTextBox)
{
TextRange textRange = new TextRange(richTextBox1.Document.ContentStart, richTextBox1.Document.ContentEnd);
if (textRange.Text.Trim().Equals("Place Holder"))
{
((RichTextBox)sender).Foreground = Brushes.Black;
richTextBox1.Document.Blocks.Clear();
}
}
}
private void rtb_LostKeyboardFocus(object sender, KeyboardFocusChangedEventArgs e)
{
//Make sure sender is the correct Control.
if (sender is RichTextBox)
{
//If nothing was entered, reset default text.
TextRange textRange = new TextRange(richTextBox1.Document.ContentStart, richTextBox1.Document.ContentEnd);
if (textRange.Text.Trim().Equals(""))
{
((RichTextBox)sender).Foreground = Brushes.Gray;
((RichTextBox)sender).AppendText("Place Holder");
}
}
}
}
Maintenant, je sais que cette question a un réponse acceptée , mais je la trouve un peu plus difficile que cela ne doit être. Alors j’y ai réfléchi moi-même et j’ai trouvé une solution (que je vais vous expliquer).
Tout d’abord, vous devez comprendre comment les espaces réservés fonctionnent réellement:
- Au début, ils ont un texte gris (tel que
username):![gray placeholder]()
- Ensuite, lorsque vous démarrez en tapant, le texte de l'espace réservé disparaît et la couleur devient noire:
![amirashabani]()
- Si vous effacez ce que vous venez de taper, vous passerez à l'état
1.
Ok, maintenant nous plongons dans le code sacré : Vous avez besoin d’une variable globale booléenne et de deux événements pour que cela fonctionne.
- Définissez une variable booléenne, par exemple
firstdans la classe principale:bool first = true;. Par main class, je veux dire quelque chose comme ceci:
J'ai assigné cette variable à true, car cette variable représentera si l'utilisateur a commencé à taper ou non.
- Vous devez taper ceci dans votre code xaml, pour que votre zone de texte paraisse appropriée lorsque le formulaire est chargé:
<TextBox x:Name="usernameBox" Text="username" Foreground="Gray"/> Il ne vous manque plus que les événements KeyDown et TextChanged:
private void usernameBox_KeyDown(object sender, KeyEventArgs e) { if (first) { usernameBox.Text = string.Empty; usernameBox.Foreground = new SolidColorBrush(Colors.Black); first = false; } } private void usernameBox_TextChanged(object sender, TextChangedEventArgs e) { if (string.IsNullOrEmpty(usernameBox.Text) && !first) { usernameBox.Text = "username"; usernameBox.Foreground = new SolidColorBrush(Colors.Gray); first = true; } }
<TextBox Controls:TextBoxHelper.Watermark="Watermark"/>
Ajoutez mahapps.metro à votre projet. Ajouter une zone de texte avec le code ci-dessus à la fenêtre.
<TextBox Grid.Column="0" Name="TextBox_SearchBar" AcceptsReturn="False" AcceptsTab="False" TextWrapping="Wrap" KeyUp="TextBox_SearchBar_KeyUp" />
<TextBox Grid.Column="0" Name="TextBox_Watermark" Text="Search Test Sets" Foreground="Gray" GotFocus="TextBox_Watermark_GotFocus" />
private void TextBox_Watermark_GotFocus( object sender, RoutedEventArgs e ) {
TextBox_Watermark.Visibility = Visibility.Hidden;
TextBox_SearchBar.Focus();
}
Cela crée deux zones de texte, une pour le champ qui reçoit le filigrane et une pour le filigrane. Le champ qui reçoit le filigrane peut être un contrôle ComboBox ou un autre contrôle (tant que l'alignement est correct et que le focus est obtenu en conséquence).
Le filigrane DOIT être une zone de texte ou un autre contrôle pouvant GetFocus (un TextBlock ne peut pas GetFocus, comme je l’ai appris à la dure). Lorsque la zone de texte en filigrane est activée, elle se cache et permet d'accéder à l'autre zone de texte.
Si vous souhaitez afficher à nouveau le filigrane une fois que la zone de texte SearchBar a perdu le focus, ajoutez simplement un gestionnaire d'événements LostFocus à TextBox_SearchBar qui contrôle l'entrée et bascule en conséquence sur les masques Visible et Visible.
façon la plus simple de WaterMark Of TextBox
<Window.Resources>
<Style x:Key="MyWaterMarkStyle" TargetType="{x:Type TextBox}">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type TextBox}">
<Grid>
<Border Background="White" BorderBrush="#FF7D8683" BorderThickness="1"/>
<ScrollViewer x:Name="PART_ContentHost" Margin="5,0,0,0" VerticalAlignment="Center" />
<Label Margin="5,0,0,0" x:Name="WaterMarkLabel" Content="{TemplateBinding Tag}" VerticalAlignment="Center"
Visibility="Collapsed" Foreground="Gray" FontFamily="Arial"/>
</Grid>
<ControlTemplate.Triggers>
<MultiTrigger>
<MultiTrigger.Conditions>
<Condition Property="Text" Value=""/>
</MultiTrigger.Conditions>
<Setter Property="Visibility" TargetName="WaterMarkLabel" Value="Visible"/>
</MultiTrigger>
<Trigger Property="IsEnabled" Value="False">
<Setter Property="Foreground" Value="DimGray"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</Window.Resources>
et ajouter un style de zone de texte StaticResource
<TextBox
Style="{StaticResource MyWaterMarkStyle}"
Tag="Search Category"
Grid.Row="0"
Text="{Binding CategorySearch,Mode=TwoWay,UpdateSourceTrigger=PropertyChanged}"
TextSearch.Text="Search Category"
>
Telerik dispose d’un contrôle appelé RadWatermarkTextBox spécialement pour résoudre ce problème. Si vous utilisez les commandes Telerik, utilisez-les simplement de la manière suivante
<telerik:RadWatermarkTextBox
Text="{Binding Path=MyTextBoxText}"
WatermarkContent="Please enter some text" />