Android example source code file (AdvancedPreferences.java)

This example Android source code file (AdvancedPreferences.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Android by Example" ^TM.

Java - Android tags/keywords

advancedpreferences, android, checkboxpreference, content, handler, key_advanced_checkbox_preference, key_my_preference, onsharedpreferencechangelistener, os, override, preference, preferenceactivity, preferences, runnable, string, thanks, ui, you

The AdvancedPreferences.java Android example source code

/*
 * Copyright (C) 2007 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.example.android.apis.app;

import com.example.android.apis.R;

import android.content.SharedPreferences;
import android.content.SharedPreferences.OnSharedPreferenceChangeListener;
import android.os.Bundle;
import android.os.Handler;
import android.preference.PreferenceActivity;
import android.preference.CheckBoxPreference;
import android.widget.Toast;

/**
 * Example that shows finding a preference from the hierarchy and a custom preference type.
 */
public class AdvancedPreferences extends PreferenceActivity implements OnSharedPreferenceChangeListener {
    public static final String KEY_MY_PREFERENCE = "my_preference";
    public static final String KEY_ADVANCED_CHECKBOX_PREFERENCE = "advanced_checkbox_preference";

    private CheckBoxPreference mCheckBoxPreference;
    private Handler mHandler = new Handler();
    
    /**
     * This is a simple example of controlling a preference from code.
     */
    private Runnable mForceCheckBoxRunnable = new Runnable() {
        public void run() {
            if (mCheckBoxPreference != null) {
                mCheckBoxPreference.setChecked(!mCheckBoxPreference.isChecked());
            }
            
            // Force toggle again in a second
            mHandler.postDelayed(this, 1000);
        }
    };
    
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        // Load the XML preferences file
        addPreferencesFromResource(R.xml.advanced_preferences);
        
        // Get a reference to the checkbox preference
        mCheckBoxPreference = (CheckBoxPreference)getPreferenceScreen().findPreference(
                KEY_ADVANCED_CHECKBOX_PREFERENCE);
    }

    @Override
    protected void onResume() {
        super.onResume();

        // Start the force toggle
        mForceCheckBoxRunnable.run();
        
        // Set up a listener whenever a key changes
        getPreferenceScreen().getSharedPreferences().registerOnSharedPreferenceChangeListener(this);
    }

    @Override
    protected void onPause() {
        super.onPause();

        // Unregister the listener whenever a key changes
        getPreferenceScreen().getSharedPreferences().unregisterOnSharedPreferenceChangeListener(this);
        
        mHandler.removeCallbacks(mForceCheckBoxRunnable);
    }

    public void onSharedPreferenceChanged(SharedPreferences sharedPreferences, String key) {
        // Let's do something when my counter preference value changes
        if (key.equals(KEY_MY_PREFERENCE)) {
            Toast.makeText(this, "Thanks! You increased my count to "
                    + sharedPreferences.getInt(key, 0), Toast.LENGTH_SHORT).show();
        }
    }
    
}