Android - how can i know when gridview has reached the bottom?

问题

I'm building an app that loads images from JSON and displays them as grid view. the problem is that there are hundreds of images and i want to load 20 each time, I want to download more pictures from the server when the scroll reaches the bottom. so, how can i tell when the grid

view reaches the bottom? I've searched the web and couldn't figure this one...

anyone have ideas?

I'm adding a photo of an app that does something very similar to what i want. thanks.

回答1:

You can use setOnScrollListener to your GridView.

Here is the code example:

gridView.setOnScrollListener(new OnScrollListener(){
    @Override
    public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount)
       {
        if(firstVisibleItem + visibleItemCount >= totalItemCount){
            // End has been reached
        }
    }

    @Override
    public void onScrollStateChanged(AbsListView view, int scrollState){

    }
});

回答2:

And here is my solution, You may want to simply override the onOverScrolled method :

@Override
protected void onOverScrolled(int scrollX, int scrollY, boolean clampedX, boolean clampedY) {
    super.onOverScrolled(scrollX, scrollY, clampedX, clampedY);

    View view = (View) getChildAt(getChildCount()-1);
    int diff = (view.getBottom()-(getHeight()+getScrollY()));

    if(diff==0) {
           //overscroll on bottom
       } else {
           //overscroll on top
       }    
}

来源：https://stackoverflow.com/questions/20276396/android-how-can-i-know-when-gridview-has-reached-the-bottom