Push to refresh on android as in gmail (and not pull to refresh like on iphone)

Question

There have been many requests for a push to refresh widget or library on android, even if some people consider it's not such a good ui pattern (I must say I belong to this camp).

But what about "pull to refresh" or to be more precise : the mechanism used in gmail for android 4. When you reach the bottom of the list, you get the last element. But if you scroll up again (push) then a new list item appears with a infinite progress bar and the next mails will load and fill up the list.

Other android coders and UI designers have noticed that, but I can't find any good debate about this pattern, neither can I find an implementation of this feature to fill a list.

Has anyone seen an interesting solution to this problem ?

Answer 1

here is two helpful libraries:

• https://github.com/johannilsson/android-pulltorefresh
• https://github.com/chrisbanes/Android-PullToRefresh

Answer 2

you can try implementing it by yourself. Its quite easy:

How I did:

1) set your listview's onScrollStateChange:

@Override
public void onScrollStateChanged(AbsListView listView, int scrollState) {
    if (scrollState == SCROLL_STATE_IDLE) {
        if (listView.getLastVisiblePosition() >= listView.getCount()-1) {
                //scroll reached the end, trigger the method to load more itens!                
        }
    }
}

2) in your base adapter:

private static final int TYPE_VIEW_COUNT = 2;
private static final int TYPE_VIEW_CONTENT = 0;
private static final int TYPE_VIEW_LOADING = 1; 

@Override
public int getItemViewType(int position) {

    if (position == (getCount()-1)) {
        return TYPE_VIEW_LOADING;
    } else {
        return TYPE_VIEW_CONTENT;
    }           

}

@Override
public int getViewTypeCount() {
    return TYPE_VIEW_COUNT;
}



@Override
public int getCount() {
    //return list size + 1;
}


@Override
public View getView(int position, View convertView, ViewGroup parent) {

    View view = null;

    switch (getItemViewType(position)) {

    case TYPE_VIEW_CONTENT:

        //load your content view (using convertView and then...)

        break;
    case TYPE_VIEW_LOADING:
        //load your loading view (indeterminate progressbar)
        break;
    }



    return view;        

}