Question

Hello i use AVD and I don’t know how to error stack when I get -> app stopped working force quit…

I wanted to code simple listener but there was an error -> i know that error is caused by setOnClick listener and this is probalby null pointer exception, but I would like to see it on stack error. Please tell me also why there is an exception. I attach the part of XML

package com.example.pierwsza;

 import android.os.Bundle;
 import android.app.Activity;
 import android.content.DialogInterface;
 import android.content.DialogInterface.OnClickListener;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.support.v4.app.NavUtils;

class MainActivity extends Activity implements OnClickListener{
Button b;
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    b = (Button) findViewById(R.id.button3);
   // b.setOnClickListener((android.view.View.OnClickListener) this); <--- ERROR
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    getMenuInflater().inflate(R.menu.activity_main, menu);
    return true;
}

public void onClick(DialogInterface dialog, int which) {
    //b.setText("Ale to dziwne");

}


}

---

XML of that BUTTON

 <Button
    android:id="@+id/button3"
    style="?android:attr/buttonStyleSmall"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignBottom="@+id/linearLayout1"
    android:layout_marginBottom="29dp"
    android:layout_toLeftOf="@+id/textView1"
    android:text="Jakis przycisk" />

Answer 1

If you are using Eclipse to code, go to Window -> Show View -> LogCat to see the error stack thrown by your app.

To fix this particular error change this:

public void onClick(DialogInterface dialog, int which) {
    //b.setText("Ale to dziwne");
}

To use a View.OnClickListener() like this:

public void onClick(View view) {
    //b.setText("Ale to dziwne");
}

And press Ctrl+Shift+O to update your import statements from DialogInterface.OnClickListener to View.OnClickListener.