How do I change the background color of my android app based on user input?

Question

I have three difficulty modes for my app; Easy, Medium, and Hard. I have a variable that keeps track of the difficulty (0-2). How can I use this variable to change the background color of my app? For example, when the mode is easy I want the background to be green, yellow for medium, and red for hard.

Here is what I have in my layout.

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
    android:id="@+id/relativeLayout1"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@color/myBackground" >

</RelativeLayout>

And I have the string resource:

<?xml version="1.0" encoding="utf-8"?>
<resources>
<color name="myBackground">#01CC18</color>
</resources>

However, what I want to do is be able to change the background in the program itself instead of in the xml layouts. Can this be done?

Answer 1

Fill your main view with a LinearLayout. Then get a handle to this layout:

LinearLayout layout = (LinearLayout) findViewById(R.id.linearLayout1);

You can use this handle to update the background color whenever your difficulty changes:

switch(difficulty) {
case 0:
    layout.setBackgroundColor(android.R.color.green);
    break;
case 1:
    layout.setBackgroundColor(android.R.color.orange);
    break;
case 2:
    layout.setBackgroundColor(android.R.color.red);
    break;
default:
    break;
}

Answer 2

I think this is what are you looking for:

http://android-developers.blogspot.com/2009/03/window-backgrounds-ui-speed.html