Kivy Android app running in background crashes when intent tries to pull it to top

@EmmaCaunter commented on May 4, 2018, 6:17 PM UTC:

Versions

• Python: 2.7
• OS: Android
• Kivy: master
• Kivy installation method: Git

Description

When the app is in the background, I want to use Android’s Intent to bring app back to top. When the intent activates, the app instantly crashes and then restarts. This issue occurs with the new toolchain but not with the old one.

Code and Logs

Code to replicate:

***************

from kivy.app import App
from kivy.uix.button import Button
from android.broadcast import BroadcastReceiver
from jnius import autoclass
from plyer.platforms.android import SDK_INT

PythonActivity = autoclass('org.kivy.android.PythonActivity')
NotificationBuilder = autoclass('android.app.Notification$Builder')
Context = autoclass('android.content.Context')
Intent = autoclass('android.content.Intent')
PendingIntent = autoclass('android.app.PendingIntent')
Uri = autoclass('android.net.Uri')
Notification = autoclass('android.app.Notification')
AndroidString = autoclass('java.lang.String')

class TestApp(App):
    def build(self):

        return Button(text='Hello World')

    def on_resume(self):
        print "On resume"

    def on_pause(self):
        print "on pause"

        activity = PythonActivity.mActivity
        Drawable = autoclass("{}.R$drawable".format(activity.getPackageName()))

        notification_service = activity.getSystemService(Context.NOTIFICATION_SERVICE)

        icon = getattr(Drawable, 'icon')
        noti = NotificationBuilder(activity)

        noti.setPriority(Notification.PRIORITY_MAX)
        noti.setDefaults(Notification.DEFAULT_ALL)  

        noti.setContentTitle(AndroidString(("title").encode('utf-8')))
        noti.setContentText(AndroidString(("message").encode('utf-8')))
        noti.setSmallIcon(icon)
        id = 22701

        app_intent = Intent(Intent.ACTION_PROVIDER_CHANGED)
        pending_intent = PendingIntent.getBroadcast(activity, id, app_intent, PendingIntent.FLAG_UPDATE_CURRENT)
        app_intent.setData(Uri.parse('close'))

        if not hasattr(self, 'br'):
             self.broadcast_receiver = BroadcastReceiver(
                 self.on_broadcast, actions=['provider_changed', 'run'])
             self.broadcast_receiver.start()

        noti.addAction(0, AndroidString("Start"), pending_intent)
        if SDK_INT >= 16:
            noti = noti.build()
        else:
            noti = noti.getNotification()
        notification_service.notify(0, noti)
        return True

    def on_broadcast(self, context, intent):
        print "On Broadcast"
        activity = PythonActivity.mActivity
        notification_service = activity.getSystemService(Context.NOTIFICATION_SERVICE)
        notification_service.cancel(0)
        intent = Intent(activity.getApplicationContext(), PythonActivity)
        intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_REORDER_TO_FRONT)
        activity.getApplicationContext().startActivity(intent)

TestApp().run()

**************

Put app into background, which triggers notification. Touch notification to re-open app, and the app crashes with the following error:

A/libc: Fatal signal 11 (SIGSEGV), code 1, fault addr 0x4 in tid 7199 (SDLThread)

More detailed logging reveals the following SIGSEGV fingerprint:

04-30 15:53:41.350 3138-3269/? I/bt-btm: BTM_CheckAdvData type=0x19
04-30 15:53:41.350 3138-3269/? I/bt-btm: BTM_CheckAdvData type=0x03
04-30 15:53:41.350 3138-3269/? D/bt-btm: BR/EDR NOT support bit not set, treat as DUMO
04-30 15:53:41.350 458-458/? I/DEBUG: *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** ***
04-30 15:53:41.350 458-458/? I/DEBUG: Build fingerprint: 'htc/bm/htc_m8:5.0.1/LRX22C/463267.2:user/release-keys'
04-30 15:53:41.350 458-458/? I/DEBUG: Revision: '0'
04-30 15:53:41.350 458-458/? I/DEBUG: ABI: 'arm'
04-30 15:53:41.350 458-458/? I/DEBUG: pid: 9964, tid: 10051, name: SDLThread  >>> com.test.example <<<
04-30 15:53:41.360 458-458/? I/DEBUG: signal 11 (SIGSEGV), code 1 (SEGV_MAPERR), fault addr 0x4
04-30 15:53:41.360 458-458/? I/DEBUG:     r0 a0e3e108  r1 a0e3e108  r2 fffffc7c  r3 00000000
04-30 15:53:41.360 458-458/? I/DEBUG:     r4 00000001  r5 97eb9ae8  r6 9dd4ee40  r7 00000001
04-30 15:53:41.360 458-458/? I/DEBUG:     r8 00000001  r9 97eb9ae8  sl 00000001  fp b3e620c0
04-30 15:53:41.360 458-458/? I/DEBUG:     ip a0e5fb00  sp 97eb5810  lr a0da36f9  pc a0da31dc  cpsr 600b0030
04-30 15:53:41.370 458-458/? I/DEBUG: backtrace:
04-30 15:53:41.370 458-458/? I/DEBUG:     #00 pc 000c61dc  /data/app/com.test.example-1/lib/arm/libpython2.7.so (PySys_GetObject+11)
04-30 15:53:41.370 458-458/? I/DEBUG:     #01 pc 000c66f5  /data/app/com.test.example-1/lib/arm/libpython2.7.so (PySys_SetArgvEx+84)
04-30 15:53:41.440 3138-3269/? I/bt-hci: BLE HCI(id=62) event = 0x02)
04-30 15:53:41.440 3138-3269/? I/bt-hci: btu_ble_process_adv_pkt
04-30 15:53:41.440 3138-3269/? D/bt-btm: btm_ble_process_adv_pkt:bda= 28:39:5e:4f:c9:b7

This issue was moved by tshirtman from kivy/kivy/issues/5728.

[brvier]

Verified that singleTask also works. @brvier I saw that you tried this before, but maybe the behaviour has been fixed by the recent update to SDL2.0.9.

Sorry to not have answer before, indeed look like fixed with various SDL2.0.9 or master…

[inclement]

Thanks @EmmaCaunter for the clear example, it would have been much harder to debug without it.