Add button to choose default launcher

app/src/main/java/com/finnmglas/launcher/SettingsActivity.kt

@@ -7,9 +7,13 @@ import android.content.DialogInterface
 import android.content.Intent
 import android.content.SharedPreferences
 import android.net.Uri
+import android.os.Build
 import android.os.Bundle
+import android.provider.Settings
 import android.view.View
 import android.view.WindowManager
+import android.widget.Toast
+import androidx.annotation.RequiresApi
 import androidx.appcompat.app.AppCompatActivity
 
 
@@ -70,6 +74,29 @@ class SettingsActivity : AppCompatActivity() {
         finish()
     }
 
+    fun setLauncher(view: View) {
+        // on newer sdk: choose launcher
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
+            val callHomeSettingIntent = Intent(Settings.ACTION_HOME_SETTINGS)
+            startActivity(callHomeSettingIntent)
+        }
+        // on older sdk: open launcher
+        else {
+            val pm = applicationContext.packageManager
+            val intent: Intent? = pm.getLaunchIntentForPackage("com.sec.android.app.launcher")
+
+            if (intent!=null){
+                applicationContext.startActivity(intent)
+            } else {
+            Toast.makeText(
+                this,
+                "Open settings to choose an app for this action",
+                Toast.LENGTH_SHORT
+            ).show()
+        }
+        }
+    }
+
     // Show a dialog prompting for confirmation
     fun resetSettingsClick(view: View) {
         AlertDialog.Builder(this)

app/src/main/res/layout/activity_settings.xml

@@ -62,6 +62,7 @@
                 android:id="@+id/btn_choose_up"
                 android:layout_width="wrap_content"
                 android:layout_height="wrap_content"
+                android:alpha=".8"
                 android:onClick="chooseUpApp"
                 android:text="Choose App" />
         </TableRow>
@@ -82,6 +83,7 @@
                 android:id="@+id/btn_choose_down"
                 android:layout_width="wrap_content"
                 android:layout_height="wrap_content"
+                android:alpha=".8"
                 android:onClick="chooseDownApp"
                 android:text="Choose App" />
 
@@ -103,6 +105,7 @@
                 android:id="@+id/btn_choose_left"
                 android:layout_width="wrap_content"
                 android:layout_height="wrap_content"
+                android:alpha=".8"
                 android:onClick="chooseLeftApp"
                 android:text="Choose App" />
         </TableRow>
@@ -123,6 +126,7 @@
                 android:id="@+id/btn_choose_right"
                 android:layout_width="wrap_content"
                 android:layout_height="wrap_content"
+                android:alpha=".8"
                 android:onClick="chooseRightApp"
                 android:text="Choose App" />
 
@@ -144,6 +148,7 @@
                 android:id="@+id/btn_choose_volume_up"
                 android:layout_width="wrap_content"
                 android:layout_height="wrap_content"
+                android:alpha=".8"
                 android:onClick="chooseVolumeUpApp"
                 android:text="Choose App" />
         </TableRow>
@@ -164,6 +169,7 @@
                 android:id="@+id/btn_choose_volume_down"
                 android:layout_width="wrap_content"
                 android:layout_height="wrap_content"
+                android:alpha=".8"
                 android:onClick="chooseVolumeDownApp"
                 android:text="Choose App" />
 
@@ -172,13 +178,14 @@
     </TableLayout>
 
     <TableLayout
-        android:id="@+id/buttons"
+        android:id="@+id/buttonsdanger"
         android:layout_width="0dp"
         android:layout_height="wrap_content"
         app:layout_constraintBottom_toBottomOf="parent"
         app:layout_constraintEnd_toEndOf="parent"
         app:layout_constraintStart_toStartOf="parent"
-        app:layout_constraintTop_toBottomOf="@+id/actionschooser">
+        app:layout_constraintTop_toBottomOf="@+id/actionschooser"
+        app:layout_constraintVertical_bias="0.48000002">
 
         <TableRow
             android:layout_width="match_parent"
@@ -186,14 +193,21 @@
             android:gravity="center">
 
             <Button
-                android:id="@+id/button2"
                 android:layout_width="wrap_content"
                 android:layout_height="wrap_content"
+                android:alpha=".3"
                 android:onClick="resetSettingsClick"
                 android:text="Reset" />
 
             <Button
-                android:id="@+id/button3"
+                android:id="@+id/button2"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:alpha=".3"
+                android:onClick="setLauncher"
+                android:text="Choose Launcher" />
+
+            <Button
                 android:layout_width="wrap_content"
                 android:layout_height="wrap_content"
                 android:onClick="backHome"