diferrence between R & android.R class

Question

Can anyone explain from this question; whats the difference of 'R' between

R.id.myListView

&

android.R.layout.simple_list_item_1

Isn't these 2 'R' the same class?

* Some people has down voted this question. I need to ask them the reason. If you answered the duplicate question & then down voted me it would have made sense. Neither answered my question nor the duplicate one!!! I mean whats the point of down voting some one without even helping? isn't this site supposed to be for help for programmers!! Weird!! **

No, they are in different packages. One is in `android`, the other is in `your.packagename` — Ken Wolf, Jun 08 '13 at 06:05

score 13 · Accepted Answer · edited May 02 '16 at 17:56

13

R.layout.*, R.id.*,in fact any R.something without the android.- part in front of it refers to some resource in your resources folders, e.g. drawables, strings, layouts, ids of widgets etc. android.R.* refers to standard android items that come shipped with your SDK

edited May 02 '16 at 17:56

Jamie Bull

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answered Jun 08 '13 at 06:30

thomi

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score 1 · Answer 2 · edited Jun 08 '13 at 06:10

R.id.myListView

Your R.java file (Generated automatically in project/gen folder) When your application is compiled, aap generates the R class, which contains resource IDs for all the resources in your res/ directory. For each type of resource, there is an R subclass (for example, R.drawable for all drawable resources) and for each resource of that type, there is a static integer (for example, R.drawable.icon). This integer is the resource ID that you can use to retrieve your resource.

android.R.layout.simple_list_item_1

For example android.R.id.text1 (in Java) is an identifier of a TextView in the Android framework. You can find it in many layouts from the framework (select_dialog_item, select_dialog_singlechoice, simple_dropdown_item_1line, etc.).

Thanks dude, made it loud & clear.. :-) – Shaon Hasan Jun 08 '13 at 06:38 — Shaon Hasan, Jun 08 '13 at 06:38

score 0 · Answer 3 · answered Jun 08 '13 at 06:08

android.R is a built in set of constants provided as a part of the Android app framework. The other R class is a generated representation of your xml resources.

It is valid Java/Android to have multiple classes with the same name, as long as they are in different packages (which is the case here).

score 0 · Answer 4 · answered Jun 08 '13 at 06:08

0

R.id.MyListview :- R is a class here it is your package Resource

android.R.layout.simple_list_item_1 :- it is android R/Resource class,and you are trying to use it to get layout id of simple_list_item layout

answered Jun 08 '13 at 06:08

AAnkit

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score 0 · Answer 5 · answered Jun 08 '13 at 06:19

0

R.* is defined by yours. android.R.* is pre defined.

answered Jun 08 '13 at 06:19

Gunaseelan

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diferrence between R & android.R class

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