Question

am very much a newbie when it comes to android development so bear with me. Im currently using Windows 8 / Eclipse.

My issue is, the findViewById function seems to have gone mad, although I could very well be using it wrongly.

The app was working fine, then I ‘dropped’ a few new TextViews on the page which seems to totally confuse it.

The findViewById function now either finds the wrong control completely, or doesnt find anything at all (and will return null). I’ve checked my activity_main.xml file and the id’s are still correct.

Can anyone help?

This is a typical example of my usage:

public void toggleButtonNetwork_Click(View v) {
  ToggleButton tb = (ToggleButton) this.findViewById(R.id.toggleButtonNetwork);//did work, now does not work!
}

The only insight I may add is that my R.java file looked like this when it was working:

...
    public static final class id {
      public static final int menu_settings=0x7f070004;
      public static final int textViewGPS=0x7f070003;
      public static final int textViewNetwork=0x7f070001;
      public static final int toggleButtonGPS=0x7f070002;
      public static final int toggleButtonNetwork=0x7f070000;
    }
...

and now looks like this (broken):

public static final class id {
    public static final int menu_settings=0x7f070006;
    public static final int textView1=0x7f070004;
    public static final int textView2=0x7f070005;
    public static final int textViewGPS=0x7f070002;
    public static final int textViewNetwork=0x7f070003;
    public static final int toggleButtonGPS=0x7f070000;
    public static final int toggleButtonNetwork=0x7f070001;
}

Answer 1

This is a quite common problem. Try and invoke the Project/Clean... on your project. It sometimes happens that the automatic generating of the R classes goes wrong and this will force them to be rebuilt.