Android: get position of item in a listview given its id:

Question

getItemIdAtPosition() is a function in android used to get the id of an item in a list view given its position

is there any way of doing the reverse, i.e. getting the position of an item is a list view given its id?

Answer 1

No. You have to do it manually. Create a public method inside the adapter you are using; in that method, loop on the adapter items and check each item id. If it is == to the method param, then return the index.

public int getItemPosition(long id)
{
    for (int position=0; position<mList.size(); position++)
        if (mList.get(position).getId() == id)
            return position;
    return 0;
}

Update: You might as well save a HashMap for position/id in your adapter, if lookup performance represents a problem for your use case.

Update: If you want to use this method outside the adapter, then use below:

private int getAdapterItemPosition(long id)
{
    for (int position=0; position<mListAdapter.getCount(); position++)
        if (mListAdapter.get(position).getId() == id)
            return position;
    return 0;
}

Answer 2

Not sure if the question is still open. Nevertheless, thought I will share how I did it so that it may help someone who is looking to do the same thing.

You can use the tag feature of a view to store the mapping between that view's id and its position in the list.

The documentation for tags on the android developer site explains it well:

http://developer.android.com/reference/android/view/View.html#Tags

http://developer.android.com/reference/android/view/View.html#setTag(int, java.lang.Object)

http://developer.android.com/reference/android/view/View.html#getTag(int)

Example: In the getView method of your list adapter, you can set the mapping for that view's id and its position in the list, something like:

public View getView (int position, View convertView, ViewGroup parent)
{
     if(convertView == null)
     {
          // create your view by inflating a xml layout resource or instantiating a
          // custom view class
     }
     else
     {
          // Do whatever you want with the convertView object like
          // finding a child view that you want to set some property of,etc.  
     }

     // Here you set the position of the view in the list as its tag
     convertView.setTag(convertView.getId(),position);

     return convertView;
}

To retrieve the position of the view, you would do something like:

int getItemPosition(View view)
{
    return view.getTag(view.getId());
}

A point to be noted is that you do need to have a reference to the View whose position you want to retrieve. How you get hold of the View's reference is dependent on your specific case.