Supporting Multiple Screens (2560X1600 and 1280x720)

Question

I have requirement to support all screen sizes on Android (Phones and Tablets). I have a set of images with resolutions 1280x720 and 2560x1600.

Question

How to name drawable and layout folders, so that these images are scaled correctly for all resolutions(if possible) ?

I'm clear that the question has been asked very often, but all I can find are half answers. I tried to create drawable folders with names:

• drawable-xlarge-mdpi - for 1200X800
• drawable-xlarge-xhdpi - for 2560X1600

And for layout, with names:

• layout-xlarge-mdpi - for 1280x720
• layout-xlarge-xhdpi - for 25601600

And added a manifest entry:

   <supports-screens
        android:anyDensity="true"
        android:largeScreens="true"
        android:normalScreens="true"
        android:smallScreens="true" />

But now, it works only for tablets. On phones it always fails with error.

I found an answer here: Drawables for qHD resolution

As I understand, all scaling occurs through code. But can anyone explain to me how to scale the image in the code with a resolution of 1280x720 and 2560x1600 and in which folder are to be placed in ?

I have read:

Application Skeleton to support multiple screen

Android : App support for multiple tablet screen resolutions

http://developer.android.com/guide/practices/screens_support.html

Android: support multiple screens

and many more.