Added a user preference "keep screen on" (Z#23212576)

pretixscan/app/src/main/java/eu/pretix/pretixscan/droid/AppConfig.kt

@@ -343,6 +343,10 @@ class AppConfig(ctx: Context) : ConfigStore {
         get() = default_prefs.getBoolean(PREFS_KEY_USE_CAMERA, true)
         set(value) = default_prefs.edit().putBoolean(PREFS_KEY_USE_CAMERA, value).apply()
 
+    var keepScreenOn: Boolean
+        get() = default_prefs.getBoolean(PREFS_KEY_SCREEN_ALWAYS_ON, true)
+        set(value) = default_prefs.edit().putBoolean(PREFS_KEY_SCREEN_ALWAYS_ON, value).apply()
+
     val hideNames: Boolean
         get() = default_prefs.getBoolean(PREFS_KEY_HIDE_NAMES, false)
 
@@ -452,5 +456,6 @@ class AppConfig(ctx: Context) : ConfigStore {
         val PREFS_KEY_KIOSK_MODE = "pref_kiosk_mode"
         val PREFS_KEY_MULTI_EVENT_MODE = "multi_event_mode"
         private const val PREFS_KEY_KNOWN_LIVE_EVENT_SLUGS = "cache_known_live_event_slugs"
+        private const val PREFS_KEY_SCREEN_ALWAYS_ON = "pref_screen_always_on"
     }
 }

pretixscan/app/src/main/java/eu/pretix/pretixscan/droid/PretixScan.kt

@@ -1,9 +1,14 @@
 package eu.pretix.pretixscan.droid
 
+import android.app.Activity
+import android.app.Application
 import android.database.sqlite.SQLiteException
 import android.os.Build
+import android.os.Bundle
+import android.view.WindowManager
 import androidx.appcompat.app.AppCompatDelegate
 import androidx.multidex.MultiDexApplication
+import androidx.preference.PreferenceManager
 import app.cash.sqldelight.db.QueryResult
 import app.cash.sqldelight.driver.android.AndroidSqliteDriver
 import eu.pretix.libpretixsync.check.AsyncCheckProvider
@@ -24,7 +29,7 @@ import net.zetetic.database.sqlcipher.SQLiteDatabaseHook
 import java.util.concurrent.locks.ReentrantLock
 
 
-class PretixScan : MultiDexApplication() {
+class PretixScan : MultiDexApplication(), Application.ActivityLifecycleCallbacks {
     val fileStorage = AndroidFileStorage(this)
     val syncLock = ReentrantLock()
     lateinit var connectivityHelper: ConnectivityHelper
@@ -111,7 +116,7 @@ class PretixScan : MultiDexApplication() {
         }
 
         // Uncomment LogSqliteDriver for verbose logging
-        val driver = if(BuildConfig.DEBUG) {
+        val driver = if (BuildConfig.DEBUG) {
 //            LogSqliteDriver(androidDriver) {
 //                Log.d("SQLDelight", it)
 //            }
@@ -135,6 +140,9 @@ class PretixScan : MultiDexApplication() {
         }
 
         connectivityHelper = ConnectivityHelper(AppConfig(this))
+
+
+        registerActivityLifecycleCallbacks(this)
     }
 
     fun getCheckProvider(conf: AppConfig): TicketCheckProvider {
@@ -162,6 +170,35 @@ class PretixScan : MultiDexApplication() {
         }
     }
 
+    override fun onActivityCreated(
+        activity: Activity,
+        savedInstanceState: Bundle?
+    ) {
+    }
+
+    override fun onActivityDestroyed(activity: Activity) {}
+
+    override fun onActivityPaused(activity: Activity) {}
+
+    override fun onActivityResumed(activity: Activity) {
+
+        if (AppConfig(this).keepScreenOn) {
+            activity.window.addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON)
+        } else {
+            activity.window.clearFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON)
+        }
+    }
+
+    override fun onActivitySaveInstanceState(
+        activity: Activity,
+        outState: Bundle
+    ) {
+    }
+
+    override fun onActivityStarted(activity: Activity) {}
+
+    override fun onActivityStopped(activity: Activity) {}
+
     companion object {
         /*
      * It is not a security problem that the keystore password is hardcoded in plain text.

pretixscan/app/src/main/java/eu/pretix/pretixscan/droid/ui/Utils.kt

@@ -64,3 +64,4 @@ fun wipeApp(ctx: Context, shouldRevoke: Boolean = false) {
         }
     }
 }
+

pretixscan/app/src/main/res/layout/activity_event_config.xml

@@ -6,7 +6,6 @@
     android:layout_width="match_parent"
     android:layout_height="match_parent"
     android:fitsSystemWindows="true"
-    android:keepScreenOn="true"
     tools:context=".ui.EventConfigActivity">
 
     <com.google.android.material.appbar.AppBarLayout

pretixscan/app/src/main/res/layout/activity_eventinfo.xml

@@ -5,8 +5,7 @@
     xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
-    android:fitsSystemWindows="true"
-    android:keepScreenOn="true">
+    android:fitsSystemWindows="true">
 
     <com.google.android.material.appbar.AppBarLayout
         android:layout_width="match_parent"

pretixscan/app/src/main/res/layout/activity_generic_fragment.xml

@@ -4,8 +4,7 @@
     xmlns:app="http://schemas.android.com/apk/res-auto"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
-    android:fitsSystemWindows="true"
-    android:keepScreenOn="true">
+    android:fitsSystemWindows="true">
 
     <com.google.android.material.appbar.AppBarLayout
         android:layout_width="match_parent"

pretixscan/app/src/main/res/layout/activity_main.xml

@@ -16,7 +16,6 @@
         android:id="@+id/root_layout"
         android:layout_width="match_parent"
         android:layout_height="match_parent"
-        android:keepScreenOn="true"
         android:fitsSystemWindows="true">
 
         <com.google.android.material.appbar.AppBarLayout
@@ -201,7 +200,6 @@
                     android:id="@+id/cl_main"
                     android:layout_width="match_parent"
                     android:layout_height="match_parent"
-                    android:keepScreenOn="true"
                     tools:visibility="gone">
 
                     <ImageView

pretixscan/app/src/main/res/values-de/strings.xml

@@ -55,6 +55,7 @@
     <string name="dismiss">Schließen</string>
     <string name="settings_label_about">Über diese App</string>
     <string name="settings_label_licenses">Autoren und Lizenzen</string>
+    <string name="settings_label_screen_always_on">Bildschirm wach halten</string>
     <string name="settings_label_device_camera">Geräte-Kamera benutzen</string>
     <string name="settings_label_scan_offline">Offline scannen</string>
     <string name="settings_label_auto_offline">Offline-Modus automatisch steuern</string>

pretixscan/app/src/main/res/values/strings.xml

@@ -79,6 +79,7 @@
     <string name="settings_label_ui">User interface</string>
     <string name="settings_label_about">About this app</string>
     <string name="settings_label_licenses">Author and licenses</string>
+    <string name="settings_label_screen_always_on">Keep display awake</string>
     <string name="settings_label_device_camera">Use device camera</string>
     <string name="settings_label_scan_offline">Offline scanning</string>
     <string name="settings_label_auto_offline">Automatically turn offline mode on and off</string>

pretixscan/app/src/main/res/xml/preferences.xml

@@ -32,6 +32,10 @@
             android:title="@string/settings_label_auto_switch" />
     </PreferenceCategory>
     <PreferenceCategory android:title="@string/settings_label_ui">
+        <CheckBoxPreference
+            android:defaultValue="true"
+            android:key="pref_screen_always_on"
+            android:title="@string/settings_label_screen_always_on" />
         <CheckBoxPreference
             android:defaultValue="true"
             android:key="pref_use_camera"
@@ -68,6 +72,7 @@
             android:dependency="pref_print_badges"
             android:key="pref_print_badges_twice"
             android:title="@string/preference_badges_twice" />
+
     </PreferenceCategory>
     <PreferenceCategory android:title="@string/settings_label_details">
         <CheckBoxPreference