【Android】判斷捷徑是否存在——相容性更強(速度提升12倍)，android12倍

【Android】判斷捷徑是否存在——相容性更強(速度提升12倍)，android12倍
1原理：這個是在2.3的時候無意發現的，當我照著網上的例子查詢捷徑是否建立的時候突然應用程式掛了，說是缺少許可權。

com.android.launcher.permission.READ_SETTINGS或者com.android.launcher.permission.WRITE_SETTINGS

然後我就添加了許可權，雖然是可以判斷了，但是小米，HTC等手機都不能正常使用，這時候突然發現了網上了一段代碼，才明白了網友們的想法，現在就來簡單分析下，並做出最佳化。

String url = "content://" + authority + "/favorites?notify=true";

其實判斷捷徑也就是根據這個ContentProvider來判斷。但是我們並不知道這個authority，那麼怎麼知道呢？查詢，根據PackageManager得到ProviderInfo，然後判斷ProviderInfo的讀寫權限是否包含com.android.launcher.permission.READ_SETTINGS或者com.android.launcher.permission.WRITE_SETTINGS。

至此原理我們已經明白了。

2解決方案：1這是網上通用的寫法：

public static boolean hasShortcut(Context context, String appName) {String readSettingsPermission = "com.android.launcher.permission.READ_SETTINGS";String authority = getAuthorityFromPermission2(context, readSettingsPermission);String url = "content://" + authority + "/favorites?notify=true";final Uri CONTENT_URI = Uri.parse(url);Cursor c = context.getContentResolver().query(CONTENT_URI, null, " title= ? ", new String[] { appName }, null);if (c != null && c.moveToNext()) {return true;}return false;}@SuppressLint("NewApi")private static String getAuthorityFromPermission2(Context context, String permission) {List<PackageInfo> packs = context.getPackageManager().getInstalledPackages(PackageManager.GET_PROVIDERS);if (packs != null) {for (PackageInfo pack : packs) {ProviderInfo[] providers = pack.providers;if (providers != null) {for (ProviderInfo provider : providers) {if (permission.equals(provider.readPermission))return provider.authority;if (permission.equals(provider.writePermission))return provider.authority;}}}}return null;}

2這是我自己想的方法，雖然思路走到一起了，但是多少有點出入：

public static boolean hasShortcut(Context context, String appName) {String readSettingsPermission = "com.android.launcher.permission.READ_SETTINGS";String authority = getAuthorityFromPermission1(context, readSettingsPermission);String url = "content://" + authority + "/favorites?notify=true";final Uri CONTENT_URI = Uri.parse(url);Cursor c = context.getContentResolver().query(CONTENT_URI, null, " title= ? ", new String[] { appName }, null);if (c != null && c.moveToNext()) {return true;}return false;}private static String getAuthorityFromPermission1(Context context, String permission) {ActivityManager am = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);List<RunningAppProcessInfo> appProcessInfos = am.getRunningAppProcesses();for (int i = 0; i < appProcessInfos.size(); i++) {RunningAppProcessInfo appInfo = appProcessInfos.get(i);List<ProviderInfo> info = context.getPackageManager().queryContentProviders(appInfo.processName, appInfo.uid, PackageManager.GET_PROVIDERS);if (info != null) {for (int j = 0; j < info.size(); j++) {ProviderInfo provider = info.get(j);if (permission.equals(provider.readPermission)) {return provider.authority;}if (permission.equals(provider.writePermission)) {return provider.authority;}}}}return null;}

3這是最後一個版本，速度又提升了20%，而且相容性更強。記得加下許可權。

public static boolean hasShortcut(Context context, String appName) {long start = System.currentTimeMillis();String authority = getAuthorityFromPermission(context);if (authority == null) {return false;}long end = System.currentTimeMillis() - start;Log.e("Finals", end + "  eee");String url = "content://" + authority + "/favorites?notify=true";try {Uri CONTENT_URI = Uri.parse(url);Cursor c = context.getContentResolver().query(CONTENT_URI, null, " title= ? ", new String[] { appName }, null);if (c != null && c.moveToNext()) {return true;}} catch (Exception e) {}return false;}private static String getAuthorityFromPermission(Context context) {// 先得到預設的LauncherIntent intent = new Intent(Intent.ACTION_MAIN);intent.addCategory(Intent.CATEGORY_HOME);PackageManager mPackageManager = context.getPackageManager();ResolveInfo resolveInfo = mPackageManager.resolveActivity(intent, 0);if (resolveInfo == null) {return null;}List<ProviderInfo> info = mPackageManager.queryContentProviders(resolveInfo.activityInfo.packageName, resolveInfo.activityInfo.applicationInfo.uid, PackageManager.GET_PROVIDERS);if (info != null) {for (int j = 0; j < info.size(); j++) {ProviderInfo provider = info.get(j);if (provider.readPermission == null) {continue;}if (Pattern.matches(".*launcher.*READ_SETTINGS", provider.readPermission)) {return provider.authority;}}}return null;}

這是常用的各種案頭的許可權：

    <!-- 捷徑許可權 -->

    <uses-permissionandroid:name="com.android.launcher.permission.READ_SETTINGS"/>

    <uses-permissionandroid:name="com.android.launcher2.permission.READ_SETTINGS"/>

    <uses-permissionandroid:name="com.android.launcher3.permission.READ_SETTINGS"/>

    <uses-permissionandroid:name="org.adw.launcher.permission.READ_SETTINGS"/>

    <uses-permissionandroid:name="com.htc.launcher.permission.READ_SETTINGS"/>

    <uses-permissionandroid:name="com.qihoo360.launcher.permission.READ_SETTINGS"/>

    <uses-permissionandroid:name="com.lge.launcher.permission.READ_SETTINGS"/>

    <uses-permissionandroid:name="net.qihoo.launcher.permission.READ_SETTINGS"/>

    <uses-permissionandroid:name="org.adwfreak.launcher.permission.READ_SETTINGS"/>

    <uses-permissionandroid:name="org.adw.launcher_donut.permission.READ_SETTINGS"/>

    <uses-permissionandroid:name="com.huawei.launcher3.permission.READ_SETTINGS"/>

    <uses-permissionandroid:name="com.fede.launcher.permission.READ_SETTINGS"/>

    <uses-permissionandroid:name="com.sec.android.app.twlauncher.settings.READ_SETTINGS"/>

    <uses-permissionandroid:name="com.anddoes.launcher.permission.READ_SETTINGS"/>

    <uses-permissionandroid:name="com.tencent.qqlauncher.permission.READ_SETTINGS"/>

    <uses-permissionandroid:name="com.huawei.launcher2.permission.READ_SETTINGS"/>

    <uses-permissionandroid:name="com.android.mylauncher.permission.READ_SETTINGS"/>

    <uses-permissionandroid:name="com.ebproductions.android.launcher.permission.READ_SETTINGS"/>

    <uses-permissionandroid:name="com.oppo.launcher.permission.READ_SETTINGS"/>

    <uses-permissionandroid:name="com.lenovo.launcher.permission.READ_SETTINGS"/>

    <uses-permissionandroid:name="com.huawei.android.launcher.permission.READ_SETTINGS"/>