DevicePolicyManger().getCurrentFailedPasswordAttempts crashes app

Question

Seems like some of the DeviceAdmin functionality has been broken in Lollipop, at least on my Nexus 5.

This works perfectly on KitKat, JellyBean and Ice Cream Sandwich

@Override
public void onPasswordFailed(Context context, Intent intent) {

    DevicePolicyManager policyManager = (DevicePolicyManager)context.getSystemService(Context.DEVICE_POLICY_SERVICE);
    if(policyManager != null){
        int attempts = policyManager.getCurrentFailedPasswordAttempts();
        Log.v("TAG", "Attempts = " + attempts);
    }
}

But on my Nexus 5 with Android 5.0 Lollipop it produces the following error:

11-24 16:11:50.117  27053-27053/com.example.myapp E/AndroidRuntime﹕ FATAL EXCEPTION: main
    Process: com.example.myapp, PID: 27053
    java.lang.RuntimeException: Unable to start receiver com.example.myapp.receivers.AdminReceiver: java.lang.NullPointerException: Attempt to read from field 'int android.content.pm.UserInfo.id' on a null object reference
            at android.app.ActivityThread.handleReceiver(ActivityThread.java:2586)
            at android.app.ActivityThread.access$1700(ActivityThread.java:144)
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1355)
            at android.os.Handler.dispatchMessage(Handler.java:102)
            at android.os.Looper.loop(Looper.java:135)
            at android.app.ActivityThread.main(ActivityThread.java:5221)
            at java.lang.reflect.Method.invoke(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:372)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)
     Caused by: java.lang.NullPointerException: Attempt to read from field 'int android.content.pm.UserInfo.id' on a null object reference
            at android.os.Parcel.readException(Parcel.java:1546)
            at android.os.Parcel.readException(Parcel.java:1493)
            at android.app.admin.IDevicePolicyManager$Stub$Proxy.getCurrentFailedPasswordAttempts(IDevicePolicyManager.java:2476)
            at android.app.admin.DevicePolicyManager.getCurrentFailedPasswordAttempts(DevicePolicyManager.java:1261)
            at com.example.myapp.receivers.AdminReceiver.onPasswordFailed(AdminReceiver.java:48)
            at android.app.admin.DeviceAdminReceiver.onReceive(DeviceAdminReceiver.java:417)
            at android.app.ActivityThread.handleReceiver(ActivityThread.java:2579)
            at android.app.ActivityThread.access$1700(ActivityThread.java:144)
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1355)
            at android.os.Handler.dispatchMessage(Handler.java:102)
            at android.os.Looper.loop(Looper.java:135)
            at android.app.ActivityThread.main(ActivityThread.java:5221)
            at java.lang.reflect.Method.invoke(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:372)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)

It's been reported as an issue in the L-preview as well.

My question, what is causing this?

FYI: my app has the same problem so you are not alone. I "solved" it with a simple try catch block - at least the app will not crash anymore. — Theis Borg, Nov 24 '14 at 20:33
Thanks @TheisBorg - For now, I'll just be keeping a static reference to unlock attempts, until a hero comes and saves the day.. — Jakob Harteg, Nov 25 '14 at 07:37

score 0 · Answer 1 · answered Aug 05 '15 at 06:10

I have got same error then I realised that it may not work for the version 5.0 and above versions.So what I did is I am checking number of wrong attempts programmatically.Like If the someone wants to unlock pattern or pin if he enters wrong then receiver will catch and calls the passwordFailed() method.So I created on SharedPreference object and I am storing the number of passwordFailed() method is called. Based on that I am getting number of wrong patterns.I think this is correct way or not I don't know.

DevicePolicyManger().getCurrentFailedPasswordAttempts crashes app

1 Answers1