由网友(我是哈批)分享简介：我可以动态地设置一个活动中的preferred /默认的应用程序在那个时候我按Home键启动？如果这是不可能的，可我至少可以重置当前的默认值，这样的选择窗口重新出现？我试图通过调用PackageManager.clearPackage preferredActivities（com.android.launcher）实...

我可以动态地设置一个活动中的preferred /默认的应用程序在那个时候我按Home键启动？如果这是不可能的，可我至少可以重置当前的默认值，这样的选择窗口重新出现？我试图通过调用PackageManager.clearPackage preferredActivities（com.android.launcher）实施后，但似乎并没有做到这一点（我给我的活动SET_ preFERRED_APPLICATIONS权限）。

解决方案   

我可以动态地设置一个活动中的preferred /默认的应用程序在那个时候我按Home键启动？

没有。有没有公​​开的API这一点。

  

如果这是不可能的，可我至少可以重置当前默认设置，从而再次显示了选择窗口？

只有当您正在实现主屏幕是当前的默认。

  

我试图通过调用PackageManager.clearPackage preferredActivities（com.android.launcher）

实施后

至于该方法状态的文档，一个应用程序只能清除其自己的包（S）。

Can I set dynamically within an activity the preferred/default application that's to be launched when I push the Home key? If that's not possible, can I at least reset current defaults so that the chooser window re-appears? I tried to implement the latter by calling PackageManager.clearPackagePreferredActivities("com.android.launcher"), but that doesn't seem to do it(I gave my activity SET_PREFERRED_APPLICATIONS permission).

解决方案

Can I set dynamically within an activity the preferred/default application that's to be launched when I push the Home key?

No. There is no exposed API for this.

If that's not possible, can I at least reset current defaults so that the chooser window re-appears?

Only if you are implementing the home screen that is the current default.

I tried to implement the latter by calling PackageManager.clearPackagePreferredActivities("com.android.launcher")

As the documentation for that method states, "An application can only clear its own package(s).".