public class MainActivity extends AppCompatActivity {
public void click(View view) {
ImageView bart = (ImageView) findViewById(R.drawable.bart);
bart.animate().alpha(0);
}
}
This is the error
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'android.view.ViewPropertyAnimator android.widget.ImageView.animate()' on a null object reference
It seems that you are referencing to a drawable id
and not a view id
. Use R.id
for views, R.drawable
is for drawable resource.
Change from:
R.drawable.bart
in to:
R.id.bart
And are you sure that in onCreate()
you call setContentView()
method (which inflates layout)?
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