Add BroadcastReceiverLiveData class

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base/src/main/java/de/mm20/launcher2/lifecycle/BroadcastReceiverLiveData.kt

@@ -0,0 +1,33 @@
+package de.mm20.launcher2.lifecycle
+
+import android.content.BroadcastReceiver
+import android.content.Context
+import android.content.Intent
+import android.content.IntentFilter
+import androidx.lifecycle.LiveData
+
+class BroadcastReceiverLiveData<T>(
+    context: Context,
+    private val intentFilter: IntentFilter,
+    private val transformFunction: (Context, Intent) -> T
+): LiveData<T>() {
+
+    private val context = context.applicationContext
+    private val receiver = object: BroadcastReceiver() {
+        override fun onReceive(context: Context, intent: Intent) {
+            val newValue = transformFunction(context, intent)
+            postValue(newValue)
+        }
+
+    }
+
+    override fun onActive() {
+        super.onActive()
+        context.registerReceiver(receiver, intentFilter)
+    }
+
+    override fun onInactive() {
+        super.onInactive()
+        context.unregisterReceiver(receiver)
+    }
+}