How do you know if your ListView has enough number of items so that it can scroll?
For instance, If I have 5 items on my ListView all of it will be displayed on a si
This is how i used to check
if (listView.getAdapter() != null
&& listView.getLastVisiblePosition() == listView.getAdapter().getCount() - 1
&& listView.getChildAt(listView.getChildCount() - 1).getBottom() == listView.getBottom())
if it gives true, then list is at the bottom
boolean listBiggerThanWindow = appHeight - 50 <= mListView.getHeight();
Toast.makeText(HomeActivity.this, "list view bigger that window? " + listBiggerThanWindow, Toast.LENGTH_LONG)
.show();
if (listBiggerThanWindow) {
// do your thing here...
}
you can get dimensions in onCreate() by calling post(Runnable) on View.
As per my comment on Mike Ortiz' answer, I believe his answer is wrong:
getChildAt() only counts the children that are visible on screen. Meanwhile, getLastVisiblePosition returns the index based on the Adapter. So if the lastVisiblePosition is 8 because it's the 9th item in the list and there are only 4 visible items on screen, you're gonna get a crash. Verify it by calling getChildCount() and see. The indices for getChildAt are not the same as the indices for the data set. Check this out: ListView getChildAt returning null for visible children
Here's my solution:
public boolean isScrollable() {
int last = listView.getChildCount()-1; //last visible listitem view
if (listView.getChildAt(last).getBottom()>listView.getHeight() || listView.getChildAt(0).getTop()<0) { //either the first visible list item is cutoff or the last is cutoff
return true;
}
else{
if (listView.getChildCount()==listView.getCount()) { //all visible listitem views are all the items there are (nowhere to scroll)
return false;
}
else{ //no listitem views are cut off but there are other listitem views to scroll to
return true;
}
}
}
Diegosan's answer cannot differentiate when the last item is partially visible on the screen. Here is a solution to that problem.
First, the ListView must be rendered on the screen before we can check if its content is scrollable. This can be done with a ViewTreeObserver:
ViewTreeObserver observer = listView.getViewTreeObserver();
observer.addOnGlobalLayoutListener(new OnGlobalLayoutListener() {
@Override
public void onGlobalLayout() {
if (willMyListScroll()) {
// Do something
}
}
});
And here is willMyListScroll()
:
boolean willMyListScroll() {
int pos = listView.getLastVisiblePosition();
if (listView.getChildAt(pos).getBottom() > listView.getHeight()) {
return true;
} else {
return false;
}
}
This is the code I wrote for showing a picture after the last row of the listview:
public class ShowTheEndListview
{
private ImageView the_end_view;
private TabbedFragRootLayout main_layout;
private ListView listView;
private float pas;
private float the_end_img_height;
private int has_scroll = -1;
public ShowTheEndListview(float height)
{
the_end_img_height = height;
pas = 100 / the_end_img_height;
}
public void setData(ImageView the_end_view, TabbedFragRootLayout main_layout, ListView listView)
{
this.the_end_view = the_end_view;
this.main_layout = main_layout;
this.listView = listView;
}
public void onScroll(int totalItemCount)
{
if(totalItemCount - 1 == listView.getLastVisiblePosition())
{
int pos = totalItemCount - listView.getFirstVisiblePosition() - 1;
View last_item = listView.getChildAt(pos);
if (last_item != null)
{
if(listHasScroll(last_item))
{
// Log.e(TAG, "listHasScroll TRUE");
}
else
{
// Log.e(TAG, "listHasScroll FALSE");
}
}
}
}
private boolean listHasScroll(View last_item)
{
if(-1 == has_scroll)
{
has_scroll = last_item.getBottom() > (main_layout.getBottom() - the_end_img_height - 5) ? 1 : 0;
}
return has_scroll == 1;
}
public void resetHasScroll()
{
has_scroll = -1;
}
}
AbsListView includes this:
/**
* Check if the items in the list can be scrolled in a certain direction.
*
* @param direction Negative to check scrolling up, positive to check scrolling down.
* @return true if the list can be scrolled in the specified direction, false otherwise.
* @see #scrollListBy(int)
*/
public boolean canScrollList(int direction);
You need to override layoutChildren() and use it within that:
@Override
protected void layoutChildren() {
super.layoutChildren();
isAtBottom = !canScrollList(1);
isAtTop = !canScrollList(-1);
}