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Possible Duplicate:
Understand the R class in Android

I cant understand why use 'R' Class in android application.

 setContentView(R.layout.main);

Can explain why use R used here.

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rejo
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7 Answers7

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Your question is duplicate of Understand the R class in Android

When your application is compiled, aapt 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.

I got this detail from the below link ,check this once for more details : http://developer.android.com/guide/topics/resources/accessing-resources.html

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Nibha Jain
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R.java which is Automatically System generated file it contains the id of each resources used in Application which is used to make refrence.

Ronak Mehta
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R.class holds reference for all your android resources.. without which you cannot access any resources (drawable, layout, xmls etc) And R.class is Autogenerated.

Parag Chauhan
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ngesh
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R.class contains IDs for all your android resources.

Igor Popov
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R is the class that contains all the resource ids for your application.

Philip Sheard
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Its a resource class, contains ID for for all resources. Here you can also use

 setContentView(main);
Andro Selva
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Programmer
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0

You can find more info here: http://developer.android.com/reference/android/R.html

PhatHV
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