Question

possible duplicate

Hello friends,

I have seen many style files and see that some time @ sign was used into the parent attribute within the style tab in xml file and some without this @ like this

<style name="Theme" parent="android:style/Theme" /> 

this one is found from this style http://code.google.com/p/iosched/source/browse/android/res/values/styles.xml

<style name="AppTheme.Light" parent="@android:style/Theme.Holo.Light">

this one is found from this style http://developer.android.com/resources/samples/HoneycombGallery/res/values/styles.html

Is any difference from the above statement with/without using @? If yes then what the difference

Answer 1

The at-symbol (@) at the beginning of the string indicates that the
XML parser should parse and expand the rest of the ID string and
identify it as an ID resource. The plus-symbol (+) means that this is
a new resource name that must be created and added to our resources
(in the R.java file). There are a number of other ID resources that
are offered by the Android framework. When referencing an Android
resource ID, you do not need the plus-symbol, but must add the android
package namespace, like so:

android:id="@android:id/empty"

More are here check the document.

http://developer.android.com/guide/topics/ui/declaring-layout.html

Always directly jump on code without reading document. Really bad things anyway now I have learn this things that first read then implement