Coverage Summary for Class: ActivityLifecycleCallbackExtKt (dev.shreyaspatil.permissionFlow.utils)

1 /**
2  * Copyright 2022 Shreyas Patil
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  * http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 package dev.shreyaspatil.permissionFlow.utils
17 
18 import android.app.Activity
19 import android.app.Application
20 import android.os.Build
21 import android.os.Bundle
22 import androidx.annotation.RequiresApi
23 import kotlinx.coroutines.channels.awaitClose
24 import kotlinx.coroutines.flow.callbackFlow
25 
26 /**
27  * A flow which gives callback whenever any activity is started withing application (without
28  * configuration change) or any activity is resumed after being in multi-window or
29  * picture-in-picture mode.
30  */
31 internal val Application.activityForegroundEventFlow
32     get() = callbackFlow {
33         val callback = object : Application.ActivityLifecycleCallbacks {
34             private var isActivityChangingConfigurations: Boolean? = null
35             private var wasInMultiWindowMode: Boolean? = null
36             private var wasInPictureInPictureMode: Boolean? = null
37 
38             /**
39              * Whenever activity receives onStart() lifecycle callback, emit foreground event only
40              * when activity hasn't changed configurations.
41              */
42             override fun onActivityStarted(activity: Activity) {
43                 if (isActivityChangingConfigurations == false) {
44                     trySend(Unit)
45                 }
46             }
47 
48             override fun onActivityStopped(activity: Activity) {
49                 isActivityChangingConfigurations = activity.isChangingConfigurations
50             }
51 
52             override fun onActivityCreated(activity: Activity, savedInstanceState: Bundle?) {}
53 
54             /**
55              * Whenever application is resized after being in in PiP or multi-window mode, or exits
56              * from these modes, onResumed() lifecycle callback is triggered.
57              *
58              * Here we assume that user has changed permission from app settings after being in
59              * PiP or multi-window mode. So whenever these modes are exited, emit foreground event.
60              */
61             override fun onActivityResumed(activity: Activity) {
62                 if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
63                     if (isActivityResumedAfterMultiWindowOrPiPMode(activity)) {
64                         trySend(Unit)
65                     }
66                     wasInMultiWindowMode = activity.isInMultiWindowMode
67                     wasInPictureInPictureMode = activity.isInPictureInPictureMode
68                 }
69             }
70 
71             /**
72              * Whenever application is launched in PiP or multi-window mode, onPaused() lifecycle
73              * callback is triggered.
74              */
75             override fun onActivityPaused(activity: Activity) {
76                 if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
77                     wasInMultiWindowMode = activity.isInMultiWindowMode
78                     wasInPictureInPictureMode = activity.isInPictureInPictureMode
79                 }
80             }
81 
82             override fun onActivitySaveInstanceState(activity: Activity, outState: Bundle) {}
83             override fun onActivityDestroyed(activity: Activity) {}
84 
85             /**
86              * Returns whether [activity] was previously in multi-window mode or PiP mode.
87              */
88             @RequiresApi(Build.VERSION_CODES.N)
89             private fun isActivityResumedAfterMultiWindowOrPiPMode(activity: Activity) =
90                 (wasInMultiWindowMode == true && !activity.isInMultiWindowMode) ||
91                     (wasInPictureInPictureMode == true && !activity.isInPictureInPictureMode)
92         }
93 
94         registerActivityLifecycleCallbacks(callback)
95 
96         awaitClose {
97             // Cleanup
98             unregisterActivityLifecycleCallbacks(callback)
99         }
100     }