Beginner Android why is “id” is “Unknown member” with R.id?

Question

I\'m sure this is something dead simple as it\'s my first android app with code (the hello world example I did was just assigning a value to a string in XML). My problem is

Answer 1

The R class is code-generated for you by the Android build tools when you build your project. This means there are four possibilities:

1. You have not tried building the project yet, in which case, try that.

2. Eclipse doesn't think it needs to build the project for some reason -- try Project > Clean from the Eclipse menu (only relevant if you are using Eclipse, of course).

3. There is some bug in your manifest or one of your resources that is preventing R from being built. There should be Eclipse error indicators for this.

4. You do not have an android:id attribute in your layout, and therefore there is no R.id available.

Answer 2

I resolved the issue by deleting the bin folder and recompiling using the AIDE App.

Answer 3

You must add id to a component in the XML file. Like this:

android:id="@+id/buton1"

Now can you click mainActivity.java and write code "R.id." you a see hint to write "buton1" and no error of "id"

Answer 4

For those using AIDE having issues referencing Id, try deleting the "gen folder" located in the bin folder and recompile. The problem is the R.java class did not create a constructor called Id. So deleting the gen folder containing the R.java class and recompiling solves this issue.

Answer 5

Please make sure the xml file you pasted is called main.xml and under layout folder. And try to generate the R file again. That may help.