diff --git a/mpmaster/src/main/res/layout/activity_main.xml b/mpmaster/src/main/res/layout/activity_main.xml
index 0137320f..7eaff4ce 100644
--- a/mpmaster/src/main/res/layout/activity_main.xml
+++ b/mpmaster/src/main/res/layout/activity_main.xml
@@ -20,32 +20,40 @@
         android:id="@+id/btnEnableCam3V3"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
+        android:layout_marginStart="12dp"
+        android:layout_marginTop="12dp"
         android:text="Cam3V3 On"
-        tools:layout_editor_absoluteX="47dp"
-        tools:layout_editor_absoluteY="137dp" />
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toTopOf="parent" />
 
     <Button
         android:id="@+id/btnDisableCam3V3"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
+        android:layout_marginStart="12dp"
+        android:layout_marginTop="12dp"
         android:text="Cam3V3 Off"
-        tools:layout_editor_absoluteX="201dp"
-        tools:layout_editor_absoluteY="130dp" />
+        app:layout_constraintStart_toEndOf="@+id/btnEnableCam3V3"
+        app:layout_constraintTop_toTopOf="parent" />
 
     <Button
         android:id="@+id/btnTurnOtgOn"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
+        android:layout_marginStart="12dp"
+        android:layout_marginTop="12dp"
         android:text="OTG On"
-        tools:layout_editor_absoluteX="51dp"
-        tools:layout_editor_absoluteY="246dp" />
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toBottomOf="@+id/btnEnableCam3V3" />
 
     <Button
         android:id="@+id/btnTurnOtgOff"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
+        android:layout_marginStart="12dp"
+
         android:text="OTG Off"
-        tools:layout_editor_absoluteX="201dp"
-        tools:layout_editor_absoluteY="242dp" />
+        app:layout_constraintStart_toEndOf="@+id/btnTurnOtgOn"
+        app:layout_constraintTop_toTopOf="@+id/btnTurnOtgOn" />
 
 </androidx.constraintlayout.widget.ConstraintLayout>
\ No newline at end of file