經(jīng)常聽到大家討論類似的需求，懷疑大廠是不是用了此方案，據(jù)我個人了解，多數(shù)頭部 app 其實都是發(fā)版來更新節(jié)假日的 icon。當然本方案也是一種可選的方案，以前我也調(diào)研過，存在問題和作者所述差不多，此外原文鏈接作者也回復了很多疑問，可以同時了解。

效果圖

產(chǎn)品需求

市面上很多App能根據(jù)特定活動，動態(tài)切換應用圖標達到宣傳目的，例如淘寶雙十一，國慶節(jié)等等。那么我們怎樣才能在不發(fā)新版本的情況下，動態(tài)切換應用圖標呢？

具體方案

1.圖標更換：在AndroidManifest設置應用入口Activity的別名，然后通過setComponentEnabledSetting動態(tài)啟用或禁用別名進行圖標切換。

2.控制圖標顯示：冷啟動App時，調(diào)用接口判斷是否需要切換icon。

3.觸發(fā)時機：監(jiān)聽App前后臺切換，當App處于后臺時切換圖標，使得用戶無感知。

代碼實現(xiàn)

在AndroidManifest.xml中給入口Activity設置activity-alias

<applicationandroid:name=".MyApplication"android:allowBackup="true"android:icon="@mipmap/ic_launcher"android:label="@string/app_name"android:supportsRtl="true"android:theme="@style/Theme.SwitchIcon"><!-- 原MainActivity --><activity android:name=".MainActivity" /><!-- 固定設置一個默認的別名，用來替代原MainActivity --><activity-aliasandroid:name=".DefaultAliasActivity"android:enabled="true"android:icon="@mipmap/ic_launcher"android:label="@string/app_name"android:targetActivity=".MainActivity"><intent-filter><action android:name="android.intent.action.MAIN" /><category android:name="android.intent.category.LAUNCHER" /></intent-filter></activity-alias><!-- 別名1，特定活動需要的圖標如：雙11，國慶節(jié)等 --><activity-aliasandroid:name=".Alias1Activity"android:enabled="false"android:icon="@mipmap/ic_launcher_show"android:label="@string/app_name"android:targetActivity=".MainActivity"><intent-filter><action android:name="android.intent.action.MAIN" /><category android:name="android.intent.category.LAUNCHER" /></intent-filter></activity-alias></application>

activity-alias標簽中的屬性如下：

在MainActivity中，通過啟用或禁用別名進行圖標切換

/*** 設置默認的別名為啟動入口*/
public void setDefaultAlias() {PackageManager packageManager = getPackageManager();ComponentName name1 = new ComponentName(this, "com.fengfeibiao.switchicon.DefaultAliasActivity");packageManager.setComponentEnabledSetting(name1, PackageManager.COMPONENT_ENABLED_STATE_ENABLED, PackageManager.DONT_KILL_APP);ComponentName name2 = new ComponentName(this, "com.fengfeibiao.switchicon.Alias1Activity");packageManager.setComponentEnabledSetting(name2, PackageManager.COMPONENT_ENABLED_STATE_DISABLED, PackageManager.DONT_KILL_APP);}/*** 設置別名1為啟動入口*/
public void setAlias1() {PackageManager packageManager = getPackageManager();ComponentName name1 = new ComponentName(this, "com.fengfeibiao.switchicon.DefaultAliasActivity");packageManager.setComponentEnabledSetting(name1, PackageManager.COMPONENT_ENABLED_STATE_DISABLED, PackageManager.DONT_KILL_APP);ComponentName name2 = new ComponentName(this, "com.fengfeibiao.switchicon.Alias1Activity");packageManager.setComponentEnabledSetting(name2, PackageManager.COMPONENT_ENABLED_STATE_ENABLED, PackageManager.DONT_KILL_APP);
}

ForegroundCallbacks監(jiān)聽App前后臺切換

/*** 監(jiān)聽App前后臺切換*/
public class ForegroundCallbacks implements Application.ActivityLifecycleCallbacks {public static final long CHECK_DELAY = 500;public static final String TAG = ForegroundCallbacks.class.getName();public interface Listener {void onForeground();void onBackground();}private static ForegroundCallbacks instance;private boolean foreground = false, paused = true;private Handler handler = new Handler();private List<Listener> listeners = new CopyOnWriteArrayList<Listener>();private Runnable check;public static ForegroundCallbacks init(Application application) {if (instance == null) {instance = new ForegroundCallbacks();application.registerActivityLifecycleCallbacks(instance);}return instance;}public static ForegroundCallbacks get(Application application) {if (instance == null) {init(application);}return instance;}public static ForegroundCallbacks get(Context ctx) {if (instance == null) {Context appCtx = ctx.getApplicationContext();if (appCtx instanceof Application) {init((Application) appCtx);}throw new IllegalStateException("Foreground is not initialised and " +"cannot obtain the Application object");}return instance;}public static ForegroundCallbacks get() {if (instance == null) {throw new IllegalStateException("Foreground is not initialised - invoke " +"at least once with parameterised init/get");}return instance;}public boolean isForeground() {return foreground;}public boolean isBackground() {return !foreground;}public void addListener(Listener listener) {listeners.add(listener);}public void removeListener(Listener listener) {listeners.remove(listener);}@Overridepublic void onActivityResumed(Activity activity) {paused = false;boolean wasBackground = !foreground;foreground = true;if (check != null)handler.removeCallbacks(check);if (wasBackground) {Log.d(TAG, "went foreground");for (Listener l : listeners) {try {l.onForeground();} catch (Exception exc) {Log.d(TAG, "Listener threw exception!:" + exc.toString());}}} else {Log.d(TAG, "still foreground");}}@Overridepublic void onActivityPaused(Activity activity) {paused = true;if (check != null)handler.removeCallbacks(check);handler.postDelayed(check = new Runnable() {@Overridepublic void run() {if (foreground && paused) {foreground = false;Log.d(TAG, "went background");for (Listener l : listeners) {try {l.onBackground();} catch (Exception exc) {Log.d(TAG, "Listener threw exception!:" + exc.toString());}}} else {Log.d(TAG, "still foreground");}}}, CHECK_DELAY);}@Overridepublic void onActivityCreated(Activity activity, Bundle savedInstanceState) {}@Overridepublic void onActivityStarted(Activity activity) {}@Overridepublic void onActivityStopped(Activity activity) {}@Overridepublic void onActivitySaveInstanceState(Activity activity, Bundle outState) {}@Overridepublic void onActivityDestroyed(Activity activity) {}
}

需要在Application中調(diào)用ForegroundCallbacks.init(this)進行初始化。

在MainActivity中實現(xiàn)ForegroundCallbacks.Listener對App進行監(jiān)聽，當處于后臺判斷是否切換應用圖標

完整的MainActivity代碼：

public class MainActivity extends AppCompatActivity implements ForegroundCallbacks.Listener {private int position = 0;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);//添加app前后臺監(jiān)聽ForegroundCallbacks.get(this).addListener(this);findViewById(R.id.tv_default).setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {position = 0;}});findViewById(R.id.tv_alias1).setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {position = 1;}});}@Overrideprotected void onDestroy() {// 移除app前后臺監(jiān)聽ForegroundCallbacks.get(this).removeListener(this);super.onDestroy();}@Overridepublic void onForeground() {}@Overridepublic void onBackground() {//根據(jù)具體業(yè)務需求設置切換條件,我公司采用接口控制icon切換if (position == 0) {setDefaultAlias();} else {setAlias1();}}/*** 設置默認的別名為啟動入口*/public void setDefaultAlias() {PackageManager packageManager = getPackageManager();ComponentName name1 = new ComponentName(this, "com.fengfeibiao.switchicon.DefaultAliasActivity");packageManager.setComponentEnabledSetting(name1, PackageManager.COMPONENT_ENABLED_STATE_ENABLED, PackageManager.DONT_KILL_APP);ComponentName name2 = new ComponentName(this, "com.fengfeibiao.switchicon.Alias1Activity");packageManager.setComponentEnabledSetting(name2, PackageManager.COMPONENT_ENABLED_STATE_DISABLED, PackageManager.DONT_KILL_APP);}/*** 設置別名1為啟動入口*/public void setAlias1() {PackageManager packageManager = getPackageManager();ComponentName name1 = new ComponentName(this, "com.fengfeibiao.switchicon.DefaultAliasActivity");packageManager.setComponentEnabledSetting(name1, PackageManager.COMPONENT_ENABLED_STATE_DISABLED, PackageManager.DONT_KILL_APP);ComponentName name2 = new ComponentName(this, "com.fengfeibiao.switchicon.Alias1Activity");packageManager.setComponentEnabledSetting(name2, PackageManager.COMPONENT_ENABLED_STATE_ENABLED, PackageManager.DONT_KILL_APP);}
}

具體缺陷

具體缺陷如下：

1. 切換icon會關(guān)閉應用進程，不是崩潰所以不會上報bugly。

2. 切換icon需要時間，部分華為機型要10s左右，之后能正常打開。

3. 切換icon過程中，部分機型點擊圖標無法打開應用，提示應用未安裝。

Demo的github地址

https://github.com/FengFeiBiao/SwitchIcon