I have set the button id in xml file but while I tried to find the id of the button it showing an error xml file

<androidx.appcompat.widget.AppCompatButton
        android:id="@ id/btnrotation"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/rorationbtn"
        android:layout_below="@ id/imgbox"
        android:layout_centerInParent="true"
        android:layout_marginTop="50dp">
    </androidx.appcompat.widget.AppCompatButton>

java file

public class rotation extends AppCompatActivity {
    AppCompatButton rotate;
    ImageView imgbox;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_rotation);
        getSupportActionBar().setTitle("Rotation");
        imgbox=findViewById(R.id.imgbox);
        rotate=findViewById(R.id.btnrotation);

    }

error does not contain a declaration with id 'btnrotation'

CodePudding user response：

Just rebuild your project and run again

CodePudding user response：

Sometimes it is a bug in android studio, you can try close and reopen Android Studio. If it doesn't work, you can invalidate caches or clean project and rebuild it.

CodePudding user response：

Just click on Invalidate Caches from top Toolbar (File) , and then click on Invalidate & Restart. Thank You