How to refer to a specific class or interface in android?

Issue

I have the following class:

public class MainActivity extends AppCompatActivity

And

searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener() {
    @Override
    public boolean onQueryTextSubmit(String s) {return false;}

    @Override
    public boolean onQueryTextChange(String searchText) {
        if (searchText.length() > 0) {
            myLiveData.removeObservers(this);
        }

        return false;
    }
});

To the removeObservers() function I need to pass a LifecycleOwner object. When using this line:

myLiveData.removeObservers(this);

Inside my activity, it works fine but inside the onQueryTextChange() it fails. How to make this point to the right class and get the corresponding LifecycleOwner object?

Solution

This is not related to Android, but more related to Java and its working.

When you want to reference the outer Class inside an inner class you will use OuterClassName.this. In Your case it will be MainActivity.this

public class MainActivity extends AppCompatActivity{
    public void onCreate(){
        myLiveData.removeObservers(this);
    }
}

When working with inner class, the above code will change to this.

public class MainActivity extends AppCompatActivity{
    public void onCreate(){
        searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener(){
            @Override
            public boolean onQueryTextSubmit(String s) {return false;}

            @Override
            public boolean onQueryTextChange(String searchText) {
                if (searchText.length() > 0) {
                    myLiveData.removeObservers(MainActivity.this);
                }

                return false;
            }
        });
    }
}

Answered By - Saran Sankaran