Android ListView setSelection() does not seem to work

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I have a ListActivity that implements onListItemClick() and calls a doSomething() function of the class. The latter contains l.setSelection(position) where l is the ListView object.

Now there is a onClickListener() listening for a button click that perfoms some actions and that too calls doSomething().

In the first case, the selected item get positioned appropriately, but in the latter, nothing happens.

Any clues about this strange behaviour and how I might make it work?

17 Answers

maybe you need to use function:

ListView.setItemChecked(int position, boolean checked);

You can try 2 ways like these:
Solution A:

    mListView.post(new Runnable() {
        @Override
        public void run() {
            if (null != mListView) {
                mListView.clearFocus();
                mListView.requestFocusFromTouch();
                mListView.setSelection(0);
            }
        }
    });

In some complicated situation, this solution will bring some new problems in Android 8.x.
Besides it may cause unexpected onFocusChange().

Solution B: Define a custom view extends ListView. Override method handleDataChanged().Then setSelection(0). In CustomListView:

@Override
protected void handleDataChanged() {
    super.handleDataChanged();
    if (null != mHandleDataChangedListener){
        mHandleDataChangedListener.onChanged();
    }
}
HandleDataChangedListener mHandleDataChangedListener;

public void setHandleDataChangedListener(HandleDataChangedListener handleDataChangedListener) {
    this.mHandleDataChangedListener = handleDataChangedListener;
}

public interface HandleDataChangedListener{
    void onChanged();
}

In activity:

    mListView.setHandleDataChangedListener(new CustomListView.HandleDataChangedListener() {
        @Override
        public void onChanged() {
            mListView.setHandleDataChangedListener(null);
            mListView.setSelection(0);
        }
    });
    mAdapter.notifyDataSetChanged();

Ok, That's it.

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