Eclipse not Recognizing "R.id..." with Android

Any ideas why at times Eclipse frizzles and doesn't recognize code it did seconds ago? The "R" in the code below has the red squiggle under it when it didn't 5 minutes ago and I've change no code. This happens frequently with Eclipse and usually I shut it down and start it ag开发者_如何转开发ain and it's good to go...no go this time.

// Initialize view elements
    mSearchBox      = (EditText) this.findViewById(R.id.edittext_search);
    mSearchButton   = (Button) this.findViewById(R.id.button_search);

did you accidentally import android.R.*; by any chance? I imported this one and that makes eclipse not recognize all the other generated R classes, make sure you are importing the one from your project:

import <project_name>.R;

it sounds like the R class needs to be regenerated, try making a change to the layout file and saving it so the project rebuilds.

This is Very common problem in Android just follow this,

• Go to Project Menu
• Selection "clean" option.
• Make sure "Build Automatically Option is checked"

done, your R.java's error will get resolve.

As of Android Development Tool (ADT) 14, the resource fields such as R.id. are no longer constants when defined in the library project. This is necessary to make library projects reusable without recompiling them.

There is an easy fix for R.id. that you know is correct but Android thinks it is incorrect. (Assuming that your .xml file is correct, your java code references the correct resource, and you DO NOT have the "import android.R;" statement)

1. Position the cursor on the switch statement and right click on it.
2. Select QUICK FIX. Eclipse will convert your switch staments into if-else if-else statements.
3. This should fix the R.id. issue.

I ran into the same problem. All I did was erase the "import android.R" statement and Eclipse automatically gave me the imports that I needed. Once I hit save, all my errors went away. I struggled for three days trying to figure this out.

BTW - make sure you do this with all the files.

In addition to the answers above, this error can occur if you haven't declared the package in the AndroidManifest.xml, or you have the wrong package declared. Ensure that you have

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.applicationname" ...

If you feel that your code is correct and you still get this error then.

Right Click on Project >> Build Project and this error will go off.

You can also keep a setting where a project is built automatically

Click on Project Tab >> Build Automatically.

Hope this solves your problem!!

Did you add any image files to your drawable folder? Image files with invalid file names can also cause the same issue.