Android setting LinearLayout background programmatically

Question

I have a situation where I need to set a background on a LinearLayout programatically.

In my layout, I am setting my background using `android:background="?android:attr/activatedBackgroundIndicator", but I want to set this programatically:

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/myLayoutId"
    android:layout_width="wrap_content"
    android:layout_height="fill_parent"
    android:gravity="left|center"
    android:paddingBottom="5dip"
    android:paddingLeft="5dip"
    android:background="?android:attr/activatedBackgroundIndicator"
    android:paddingTop="5dip" >

I've tried using:

Drawable d = getActivity().getResources().getDrawable(android.R.attr.activatedBackgroundIndicator);
rootLayout.setBackgroundDrawable(d);

But it crashes. Any ideas?

Edit: I had also tried using:

rootLayout.setBackgroundResource(android.R.attr.activatedBackgroundIndicator);

10-08 15:23:19.018: E/AndroidRuntime(11133): android.content.res.Resources$NotFoundException: Resource ID #0x10102fd

Answer 1

I had the same problem and I fixed it using this piece of code.

The android.R.attr.* are pointers to the in a theme and not to the actual drawable resource defined. You have to use the TypedArray to access the id.

theView = this.inflater.inflate(R.layout.list_row_job_favorited, null);

if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.HONEYCOMB) {
  TypedArray a = mContext.obtainStyledAttributes(new int[] { android.R.attr.activatedBackgroundIndicator });
  int resource = a.getResourceId(0, 0);
  //first 0 is the index in the array, second is the   default value
  a.recycle();

  theView.setBackground(mContext.getResources().getDrawable(resource));
}

I used this in my custom list adapter when detects SDK upper and worked fine.