android - 如何仅在手机上安装了与之相关的apk时才显示菜单选项

Question

假设我有一个名为“显示”的菜单选项，我的应用程序 com.android.display 正在执行显示图片的任务。现在如果设备上没有安装 apk com.android.display，则菜单选项“display' 来了，但它没有用。所以我希望只有当这个 apk 安装在设备上时，才会出现 'display' 菜单选项。有什么方法可以在 Android 操作系统上实现这一点？

Answer 1

此特定解决方案在 Android How To on Google Sites 上

If you ever need to know if a particular app is installed on the user's device, you can use the PackageManager. From a Context class (e.g. an Activity or a Service) you can call getPackageManager(). This gives you a variety of methods, one of which is getPackageInfo(). Below is a method you might use. You might call it like this:

isAppInstalled("com.simexusa.campusmaps_full");

private boolean isAppInstalled(String uri) {
   PackageManager pm = getPackageManager();
   boolean installed = false;
   try {
      pm.getPackageInfo(uri, PackageManager.GET_ACTIVITIES);
      installed = true;
   } catch (PackageManager.NameNotFoundException e) {
      installed = false;
   }
   return installed;
}