屏幕以编程方式固定第三方应用

Question

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.

Answer 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).

Answer 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 ;)

Answer 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
}