Android开发：一个SharedPreference的工具类，方便保存和读取数据

我们平常保存一些数据，都会用到SharedPreferences，但是对它操作会有点麻烦，所以这里写了一个工具类SharedPreferencesHelper，代码如下，采用单例模式进行封装：

public class SharedPreferencesHelper {private static final String FILE_NAME = "app_data";private static SharedPreferences mSharedPreferences;// 单例private static SharedPreferencesHelper instance;// 单例private SharedPreferencesHelper(Context context) {mSharedPreferences = context.getSharedPreferences(FILE_NAME,Context.MODE_PRIVATE);}    /**     * 初始化单例     * @param context     */public static synchronized void init(Context context) {if (instance == null) {instance = new SharedPreferencesHelper(context);}}/** * 获取单例 *  * @return */public static SharedPreferencesHelper getInstance() {if (instance == null) {throw new RuntimeException("class should init!");}return instance;}/** * 保存数据 *  * @param key * @param data */public void saveData(String key, Object data) {String type = data.getClass().getSimpleName();Editor editor = mSharedPreferences.edit();if ("Integer".equals(type)) {editor.putInt(key, (Integer) data);} else if ("Boolean".equals(type)) {editor.putBoolean(key, (Boolean) data);} else if ("String".equals(type)) {editor.putString(key, (String) data);} else if ("Float".equals(type)) {editor.putFloat(key, (Float) data);} else if ("Long".equals(type)) {editor.putLong(key, (Long) data);}editor.commit();}/** * 得到数据 *  * @param key * @param defValue * @return */public Object getData(String key, Object defValue) {String type = defValue.getClass().getSimpleName();if ("Integer".equals(type)) {return mSharedPreferences.getInt(key, (Integer) defValue);} else if ("Boolean".equals(type)) {return mSharedPreferences.getBoolean(key, (Boolean) defValue);} else if ("String".equals(type)) {return mSharedPreferences.getString(key, (String) defValue);} else if ("Float".equals(type)) {return mSharedPreferences.getFloat(key, (Float) defValue);} else if ("Long".equals(type)) {return mSharedPreferences.getLong(key, (Long) defValue);}return null;}

调用方式如下

1、初始化：SharedPreferencesHelper.init(getApplicationContext());  一般放在自己的Application的onCreate方法里面执行，保证全局初始化。

2、调用saveData和getData进行数据的存储和读取。

通过以上两步就能实现对SharedPreferences的操作，是不是很方便！当然，因为存储和读取的时候需要知道键，所以可以根据我们的需求对其进行进一步封装，如下AppData类所示：

public class AppData {private String KEY_SETTING_NOTIFICATION = "key_setting_notification";private String KEY_SETTING_SOUND = "key_setting_sound";private String KEY_SETTING_VIBRATE = "key_setting_vibrate";private String KEY_SETTING_TESTENV = "key_setting_testenv";        //在这里进行扩展，加入键，然后自动生成getter和setter函数，就达到了扩展的目的public AppData(Context context) {SharedPreferencesHelper.init(context);}public void setSettingNotification(boolean bFlag) {SharedPreferencesHelper.getInstance().saveData(KEY_SETTING_NOTIFICATION, bFlag);}public boolean getSettingNotification() {return (Boolean) SharedPreferencesHelper.getInstance().getData(KEY_SETTING_NOTIFICATION, false);}public void setSettingSound(boolean bFlag) {SharedPreferencesHelper.getInstance().saveData(KEY_SETTING_SOUND, bFlag);}public boolean getSettingSound() {return (Boolean) SharedPreferencesHelper.getInstance().getData(KEY_SETTING_SOUND, false);}public void setSettingVibrate(boolean bFlag) {SharedPreferencesHelper.getInstance().saveData(KEY_SETTING_VIBRATE,bFlag);}public boolean getSettingVibrate() {return (Boolean) SharedPreferencesHelper.getInstance().getData(KEY_SETTING_VIBRATE, false);}public void setTestEnvSetting(boolean bFlag) {Log.d("imdata", "set testenv:" + bFlag);SharedPreferencesHelper.getInstance().saveData(KEY_SETTING_TESTENV,bFlag);}public boolean getTestEnvSetting() {return (Boolean) SharedPreferencesHelper.getInstance().getData(KEY_SETTING_TESTENV, false);}

调用方法如下

1、在MyApplication里面定义AppData对象：private AppData imdata = new AppData(this);

2、定义相应的方法：

public boolean getSettingSound() {return imdata.getSettingSound();}public void setSettingSound(boolean bFlag) {imdata.setSettingSound(bFlag);}

3、调用方法：MyApplication.getInstance().setSettingSound(true);  这里MyApplication也是一个单例。

通过以上封装，就非常方便和易于扩展了^_^！