@Override annotation error (android prefs)

Question

When I was trying to use this code to enable preferences into my app

import android.app.Activity;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.preference.Preference;
import android.preference.PreferenceActivity;
import android.preference.Preference.OnPreferenceClickListener;
import android.widget.CheckBox;
import android.widget.CompoundButton;
import android.widget.RadioButton;
import android.widget.Toast;
import android.widget.CompoundButton.OnCheckedChangeListener;


public class Preferences extends PreferenceActivity {

private RadioButton btn01;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    addPreferencesFromResource(R.xml.preferences);
    btn01 = (RadioButton)findViewById(R.id.RadioButton01);
    Preference customPref = (Preference) findPreference("customPref");

    customPref.setOnPreferenceClickListener(new OnPreferenceClickListener(){

        public boolean onPreferenceClick(Preference preference) {
            Toast.makeText(getBaseContext(),"The Custom Preference Has Been Clicked",Toast.LENGTH_LONG).show();
            SharedPreferences customSharedPreference = getSharedPreferences("myCutomSharedPrefs", Activity.MODE_PRIVATE);
            SharedPreferences.Editor editor = customSharedPreference.edit();
            editor.putString("myCustomPref","The preference has been clicked");
            editor.commit();
            return true;
        }


        public void CheckBox() {
            final CheckBox ThisCheckBox = (CheckBox) findViewById (R.id.checkboxPref);
            ThisCheckBox.setOnCheckedChangeListener(new OnCheckedChangeListener(){
                @Override
               public void onCheckedChanged(CompoundButton compoundButton,boolean test) {
                    if (ThisCheckBox.isChecked()){ 
                        btn01.setVisibility(0);
                    } else {
                        btn01.setVisibility(2);
                    }
                }
            });
        };
    });
}
}

An error is generated on this line

 public void onCheckedChanged(CompoundButton compoundButton,boolean test) {

saying:

Multiple markers at this line
- The method onCheckedChanged(CompoundButton, boolean) of type new 
 CompoundButton.OnCheckedChangeListener(){} must override a superclass method
- implements 
 android.widget.CompoundButton.OnCheckedChangeListener.onCheckedChanged 

If i remove the @Override annotation then the code doesn't work and a warning tells me that the that part of the code is not used locally.

Having run this past someone and baffling them I was wondering if you could help?

Are there any common scenarios that causes this error?

I thought it might be my project set up

Thanks

Answer 1

It's an implementation thing. In Java 5 vs Java 6 they changed whether you could use "Override" with an interface (since Override seems to imply that you are overriding some sort of default behavior, which you are not doing with an interface!). If you so desire, you can search in the Eclipse preferences and change it from a compilation error to a compilation warning. You code inside of the CheckBox() function looks fine to me.

However, you are never calling the CheckBox function, so that's where the 'not used locally' error is coming from. Were you meaning to call that function from within the OnPreferenceClick method?

Answer 2

You can go to Project settings --> Java Compiler, and switch the compiler compliance level to 1.6. I have to do it every time i import an existing project.

Answer 3

just wanted to share, I wrote a post based on the info I found here. I hope it's helpful!

http://qtcstation.com/2011/05/android-and-jdk-compliance/