Android App Screen Compatibility

Question

I am currently working on a app and it might be used on all android devices. I find it really challenging to adjust my XML layout files according to various screen sizes. I have surfed a lot over this topic and found a useful doc at Developer site. The document is decent and provides enough information on what should be done for screen compatibility.

Questions :

1.If I have two different layouts in folders like res/layout-sw600dp and res/layout-sw720dp , will the app automatically decides which one of these layouts is to be used ?

2.Assuming that I prefer a ListView for handsets and GridView for Tabs as a Home Page display, how will I define my layouts and how will I refer them for UI ?

Any ideas on how I can pull off the 2nd question's feature will be highly appreciated. Thanks in advance.

Answer 1

You can defferenciate it in java by checking "hasHoneycomb", tabs will give tru as return value. One way is : you can set different layout from setcontentview() according to condition.

if(hasHoneycomb()) {
setcontentView(layout_for_tabs);
} else {
setcontentView(layout_for_phones);
}

Answer 2

Yes, app automatically decide which layout file to use for current device screen.

Give the ListView and GridView different ids. In code use findViewById() method when creating views. If ListView found ( findViewById(R.id.list) returned View) app is running on handset, otherwise ( findViewById(R.id.list) returned null and findViewById(R.id.grid) returned View) app is running on tablet.

Answer 3

1) Yes, it will, based on the screen size.

2) Give them different IDs and see which one is visible:

ListView mList = (ListView) findViewById( R.id.homeList );
GridView mGrid = (GridView) findViewById( R.id.homeGrid );

if( mList != null ) {
    // set list adapter
} else if( mGrid != null ) {
    // set grid adapter 
} else {
    // neither view exists...
}

Answer 4

For question 1, Yes Android will automatically choose and decide the most suitable amongst the two.

For 2, here is link - Determine if the device is a smartphone or tablet? Hope it helps. :)