Screen pinning 3rd party apps programmatically

问题:

After achieving device ownership, I am trying to implement a method to instruct the device to lock any given app into kiosk mode (or screen pinning mode). Since I have device ownership, the user is not asked for the permission to do so.

From the developer website, brief description tells me that it is possible to do what I am trying:

http://developer.android.com/about/versions/android-5.0.html#ScreenPinning

Programmatically: To activate screen pinning programmatically, call startLockTask() from your app. If the requesting app is not a device owner, the user is prompted for confirmation. A device owner app can call the setLockTaskPackages() method to enable apps to be pinnable without the user confirmation step.

This indicates that as a device owner app, I can pin other apps without user confirmation... but I have no idea how to.

I have been able to put my own app into pinned mode.

Any help would be appreciated.

回答1:

The setLockTaskPackages() is used the specify which applications (through their package names) will be able to programmatically be pinned without user confirmation. The setLockTaskPackages() is called from your device owner app (most probably in your DeviceAdminReceiver's onEnabled() method).

So, in you owner device app, you'll have something like :

mDPM.setLockTaskPackages("com.foo.myapp");

and then, in your "com.foo.myapp" application, you will be autorized to call :

startLockTask(); 

Your application will immediately enter the Pinning mode, without any user confirmation.

If you don't first register your application with setLockTaskPackages, the application will be pinned but the user will have to confirm first.

Also notice that when an app is registered with setLockTaskPackages(), it has some different behaviours than the manual pin:

• the user cannot unpin manually the application by long-pressing Back + Recent Apps. You'll have to programmatically unpin your app with stopLockTask();
• The "Home" and "Recent Apps" buttons are invisible (not displayed)
• When the app is unpinned (via stopLockTask()), the user will directly go back to Home : no Screen lock is displayed, even if a Keyguard is set (Pattern, code, or whatever Keyguard screen).

回答2:

I've not enough reputation for a comment, just would point out that for devices with physical buttons (like the Samsung Galaxy Tab A mentioned by @chairman) one way for manage the forced unpinning of your application is to implement in your DeviceAdminReceiver class the following:

@Override public void onLockTaskModeExiting(Context context, Intent intent)

So if your user want to for the unpin you can always re-pinning your app ;)

回答3:

Here's a code snippet that should get you going:

DevicePolicyManager myDevicePolicyManager = (DevicePolicyManager) getSystemService(Context.DEVICE_POLICY_SERVICE);
mDeviceAdminSample = new ComponentName(this, DeviceAdminSample.class);

if (myDevicePolicyManager.isDeviceOwnerApp(this.getPackageName())) {
    // Device owner
    String[] packages = {this.getPackageName()};
    myDevicePolicyManager.setLockTaskPackages(mDeviceAdminSample, packages);
} else {
    // Not a device owner - prompt user or show error
}

if (myDevicePolicyManager.isLockTaskPermitted(this.getPackageName())) {
    // Lock allowed
    startLockTask();
} else {
    // Lock not allowed - show error or something useful here
}