<?xml version="1.0" encoding="utf-8"?>
<resources>

    <string name="app_name">wangqiu</string>

</resources>

<?xml version="1.0" encoding="utf-8"?>
<resources>

    <string name="app_name">玩笑</string>

</resources>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
  >

    <TextView
        android:id="@+id/h"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/app_name" />
    <Button 
        android:id="@+id/btn"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/app_name"
        android:onClick="change"
        />

</LinearLayout>

import android.content.Context;
import android.content.SharedPreferences;
import android.content.res.Configuration;
import android.content.res.Resources;
import android.preference.PreferenceManager;
import android.util.DisplayMetrics;
import java.util.Locale;

public class LanguageSettingUtil {
    //單例模式-
    private static LanguageSettingUtil instance;
    private Context context;
    //儲存當前系統的language設定-
    private String defaultLanguage;
    //儲存當前系統Locale-
    private Locale defaultLocale;
    public final static String ENGLISH = "en";
    public final static String CHINESE = "zh";

    private LanguageSettingUtil(Context paramContext) {
        //得到系統語言-
        Locale localLocale = Locale.getDefault();
        this.defaultLocale = localLocale;

        //儲存系統語言到defaultLanguage
        String str = this.defaultLocale.getLanguage();
        this.defaultLanguage = str;

        this.context = paramContext;
    }

    //檢驗自身是否被建立-
    public static LanguageSettingUtil get() {
        if (instance == null)
            throw new IllegalStateException(
                    "language setting not initialized yet");
        return instance;
    }

    //初始化-
    public static void init(Context paramContext) {
        if (instance == null) {
            instance = new LanguageSettingUtil(paramContext);
        }
    }

    // 建立Configuration-
    private Configuration getUpdatedLocaleConfig(String paramString) {

        Configuration localConfiguration = context.getResources()
                .getConfiguration();
        Locale localLocale = getLocale(paramString);
        localConfiguration.locale = localLocale;
        return localConfiguration;
    }

    //得到APP配置檔案目前的語言設定-
    public String getLanguage() {
        SharedPreferences localSharedPreferences = PreferenceManager
                .getDefaultSharedPreferences(this.context);
        //如果當前程式沒有設定language屬性就返回系統語言，如果有，就返回以前的-
        return localSharedPreferences.getString("language",
                this.defaultLanguage);
    }

    //如果配置檔案中沒有語言設定-
    public Locale getLocale() {
        String str = getLanguage();
        return getLocale(str);
    }

    //建立新Locale並覆蓋原Locale-
    public Locale getLocale(String paramString) {
        Locale localLocale = new Locale(paramString);
        Locale.setDefault(localLocale);
        return localLocale;
    }

    //重新整理顯示配置-
    public void refreshLanguage() {
        String str = getLanguage();
        Resources localResources = this.context.getResources();
        if (!localResources.getConfiguration().locale.getLanguage().equals(str)) {
            Configuration localConfiguration = getUpdatedLocaleConfig(str);
            // A structure describing general information about a display, such
            // as its size, density, and font scaling.
            DisplayMetrics localDisplayMetrics = localResources
                    .getDisplayMetrics();
            localResources.updateConfiguration(localConfiguration,
                    localDisplayMetrics);
        }
    }

    //設定系統語言-
    public void saveLanguage(String paramString) {
        PreferenceManager.getDefaultSharedPreferences(this.context).edit()
                .putString("language", paramString).commit();
    }

    //儲存系統的語言設定到SharedPreferences-
    public void saveSystemLanguage() {
        PreferenceManager.getDefaultSharedPreferences(this.context).edit()
                .putString("PreSysLanguage", this.defaultLanguage).commit();
    }

    public void checkSysChanged(String cuerSysLanguage) {
        //如果系統語言設定發生變化-
        if (!cuerSysLanguage.equals(PreferenceManager
                .getDefaultSharedPreferences(this.context).getString(
                        "PreSysLanguage", "zh"))) {
            //如果系統儲存了this物件，就在這裡修改defaultLanguage的值為當前系統語言cuerSysLanguage
            this.defaultLanguage = cuerSysLanguage;
            saveLanguage(cuerSysLanguage);
            saveSystemLanguage();
        }
    }
}

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;

public class MainActivity extends Activity {

	 private LanguageSettingUtil languageSetting;
	    private TextView h,w;
	    private Button b;
	    @Override
	    protected void onCreate(Bundle savedInstanceState) {
	        super.onCreate(savedInstanceState);
	        setContentView(R.layout.activity_main);
	        
	        h = (TextView) findViewById(R.id.h);
	        b = (Button) findViewById(R.id.btn);
	        LanguageSettingUtil.init(this);//初始化
	        languageSetting = LanguageSettingUtil.get();//檢查是否初始化
	    }


	    public void change(View view){
	        languageSetting.saveLanguage("en");//設定為"en"語言(英語)，cn,是中文
	        LanguageSettingUtil.get().refreshLanguage();// 重新整理
	        h.setText(R.string.app_name);//重新載入一次，不然介面更新不了
	        b.setText(R.string.app_name);//同上。當然 也可以使用recreate();代替這兩行程式碼不過會出現閃屏，使用者的體驗不好
	    }
}

private Configuration config;
private DisplayMetrics dm;
private Resources resources

resources = getResources();// 獲得res資源物件
config = resources.getConfiguration();// 獲得設定物件
dm = resources.getDisplayMetrics();