Android 屏幕，语言，API版本 适配和兼容性

Supporting Different Languages

http://developer.android.com/training/basics/supporting-devices/languages.html

Supporting Different Screens

http://developer.android.com/training/basics/supporting-devices/screens.html

Supporting Different Platform Versions

http://developer.android.com/training/basics/supporting-devices/platforms.html

privatevoid setUpActionBar(){
    // Make sure we're running on Honeycomb or higher to use ActionBar APIs
    if(Build.VERSION.SDK_INT >=Build.VERSION_CODES.HONEYCOMB){
        ActionBar actionBar = getActionBar();
        actionBar.setDisplayHomeAsUpEnabled(true);
    }
}