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Tentative d'invoquer la méthode virtuelle 'void Android.widget.TextView.setText (Java.lang.CharSequence)' sur une référence d'objet null

Impossible de transmettre des données d'un fragment à un autre à l'aide de l'intention. La logique est bonne .Veuillez vérifier les dernières parties de l'activité principale où j'ai envoyé des chaînes à une autre activité en utilisant putExtra.

Voici le MainActivity.Java:

public class MainActivity extends Activity implements View.OnClickListener {
EditText ed1,ed2,ed3,ed4,ed5,ed6;

Button bt1;
TextView tv1,tv2;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    ed1=(EditText)findViewById(R.id.editText);
    ed2=(EditText)findViewById(R.id.editText2);
    ed3=(EditText)findViewById(R.id.editText3);
    ed4=(EditText)findViewById(R.id.editText4);
    ed5=(EditText)findViewById(R.id.editText5);
    ed6=(EditText)findViewById(R.id.editText6);
    tv1=(TextView)findViewById(R.id.textView);
    tv2=(TextView)findViewById(R.id.textView2);
    bt1=(Button)findViewById(R.id.button);
    bt1.setOnClickListener(this);
}
public void onClick(View v)
{

    String str1=ed1.getText().toString();
   String str2=ed2.getText().toString();
    String str3=ed3.getText().toString();
    String str4=ed4.getText().toString();
    String str5=ed5.getText().toString();
    String str6=ed6.getText().toString();

    if(str1.matches("") || str2.matches("") || str3.matches(""))
    {
        tv1.setText("One or more fields missing");
        if(str4.matches("") || str5.matches("") || str6.matches(""))
        {
            tv2.setText("One or more fields missing");
        }
    }

    else {
        int age1 = Integer.parseInt(ed2.getText().toString());
        int age2 = Integer.parseInt(ed5.getText().toString());

        int l1 = str1.length();
        str1 = str1.toLowerCase();
        str4 = str4.toLowerCase();
        int l2 = str4.length();

        int[] a = new int[26];
        int[] b = new int[26];

        for (int i = 0; i < l1; i++) {

            char c = str1.charAt(i);
            int x = (int) c - 97;
            a[x]++;
        }
        for (int i = 0; i < l2; i++) {

            char c = str4.charAt(i);
            int x = (int) c - 97;
            b[x]++;
        }
        int s=0,p;
        for(int i=0;i<26;i++)
        {
            if(a[i]>b[i])
                p=a[i];
            else
                p=b[i];

            s+=p;
        }
        if(l1>l2)
            p=l1;
        else
            p=l2;
        double love1=(double)(s/p)*100;
        double love2=0.0,x;

        if(age1>age2) {
            p = age1;
        x=age2;
        }
        else {
            p = age2;
            x=age1;
        }
        love2=(double)(x/p)*100;

        Intent in=new Intent(MainActivity.this,SecondActivity.class);
        String s1=""+love1;
        String s2=""+love2;



        in.putExtra("k1",str4);
       in.putExtra("k2",str4);
        in.putExtra("k3", love1);
        in.putExtra("k4",love2);
        startActivity(in);
        finish();


    }


}


}

Voici le code de SecondActivity.Java:

public class SecondActivity extends Activity {

    TextView tv7,tv8,tv9,tv10;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_second);


    Intent in = getIntent();

    String s1 = in.getStringExtra("k1");
    String s2 = in.getStringExtra("k2");
    String s3 = in.getStringExtra("k3");
    String s4 = in.getStringExtra("k4");
    tv7=(TextView)findViewById(R.id.textView3);
    tv8=(TextView)findViewById(R.id.editText4);
    tv9=(TextView)findViewById(R.id.editText5);
    tv10=(TextView)findViewById(R.id.editText6);

    tv7.setText("Hello "+s1);
    tv8.setText("Your partner "+s2+" is really Nice");
    tv9.setText("Your love percent based on name is "+s3);
    tv10.setText("Your love percent based on age is "+s4);
}
}

Voici l'erreur que j'obtiens:

 Process: khurana.nikhil.lovemeter, PID: 4019
Java.lang.RuntimeException: Unable to start activity ComponentInfo{khurana.nikhil.lovemeter/khurana.nikhil.lovemeter.SecondActivity}: Java.lang.NullPointerException: Attempt to invoke virtual method 'void Android.widget.TextView.setText(Java.lang.CharSequence)' on a null object reference
        at Android.app.ActivityThread.performLaunchActivity(ActivityThread.Java:2325)
        at Android.app.ActivityThread.handleLaunchActivity(ActivityThread.Java:2390)
        at Android.app.ActivityThread.access$800(ActivityThread.Java:151)
        at Android.app.ActivityThread$H.handleMessage(ActivityThread.Java:1303)
        at Android.os.Handler.dispatchMessage(Handler.Java:102)
        at Android.os.Looper.loop(Looper.Java:135)
        at Android.app.ActivityThread.main(ActivityThread.Java:5257)
        at Java.lang.reflect.Method.invoke(Native Method)
        at Java.lang.reflect.Method.invoke(Method.Java:372)
        at com.Android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.Java:903)
        at com.Android.internal.os.ZygoteInit.main(ZygoteInit.Java:698)
 Caused by: Java.lang.NullPointerException: Attempt to invoke virtual method 'void Android.widget.TextView.setText(Java.lang.CharSequence)' on a null object reference
        at khurana.nikhil.lovemeter.SecondActivity.onCreate(SecondActivity.Java:32)
        at Android.app.Activity.performCreate(Activity.Java:5990)
        at Android.app.Instrumentation.callActivityOnCreate(Instrumentation.Java:1106)
        at Android.app.ActivityThread.performLaunchActivity(ActivityThread.Java:2278)

Voici activity_second.XML:

 <RelativeLayout xmlns:Android="http://schemas.Android.com/apk/res/Android"
 xmlns:tools="http://schemas.Android.com/tools"     Android:layout_width="match_parent"
Android:layout_height="match_parent"   Android:paddingLeft="@dimen/activity_horizontal_margin"
Android:paddingRight="@dimen/activity_horizontal_margin"
Android:paddingTop="@dimen/activity_vertical_margin"
Android:paddingBottom="@dimen/activity_vertical_margin"
Android:background="#cefcfd"
tools:context="khurana.nikhil.lovemeter.SecondActivity">


<TextView
    Android:layout_width="wrap_content"
    Android:layout_height="wrap_content"
    Android:text=""
    Android:id="@+id/textView3"
    Android:layout_alignParentTop="true"
    Android:layout_centerHorizontal="true"
    Android:layout_marginTop="68dp" />

<TextView
    Android:layout_width="wrap_content"
    Android:layout_height="wrap_content"
    Android:text=""
    Android:id="@+id/textView4"
    Android:layout_below="@+id/textView3"
    Android:layout_centerHorizontal="true"
    Android:layout_marginTop="51dp" />

<TextView
    Android:layout_width="wrap_content"
    Android:layout_height="wrap_content"
    Android:text=""
    Android:id="@+id/textView5"
    Android:layout_above="@+id/textView6"
    Android:layout_alignStart="@+id/textView6"
    Android:layout_marginBottom="84dp" />

<TextView
    Android:layout_width="wrap_content"
    Android:layout_height="wrap_content"
    Android:text=""
    Android:id="@+id/textView6"
    Android:layout_alignParentBottom="true"
    Android:layout_centerHorizontal="true"
    Android:layout_marginBottom="51dp" />
</RelativeLayout>

androidandroid-layoutandroid-intentandroid-activity
5
Nikhil Khurana
tv8=(TextView)findViewById(R.id.editText4);
tv9=(TextView)findViewById(R.id.editText5);
tv10=(TextView)findViewById(R.id.editText6);

Remplacez-les par:

tv8=(TextView)findViewById(R.id.textView4);
tv9=(TextView)findViewById(R.id.textView5);
tv10=(TextView)findViewById(R.id.textView6);

Vous venez d'utiliser les mauvais identifiants.

9
mrtn