Develop Reference

Can't scroll in a ListView in a swipeRefreshLayout

I'm having an issue with the SwipeRefreshLayout. I have a list view within the layout and every time I scroll upward in the list view the swipe to refresh layout is tiggered and you can never scroll back to the top of the layout. Anyone have any ideas?

I found an answer to my question. I am manually enabling the swipeRefreshLayout when the first child in the listview is at the top of the list.
listView.setOnScrollListener(new AbsListView.OnScrollListener() {
#Override
public void onScrollStateChanged(AbsListView view, int scrollState) {
}
#Override
public void onScroll(AbsListView listView, int firstVisibleItem, int visibleItemCount, int totalItemCount) {
int topRowVerticalPosition = (listView == null || listView.getChildCount() == 0) ?
0 : expandableListview.getChildAt(0).getTop();
refresh.setEnabled((topRowVerticalPosition >= 0));
}
});

https://developer.android.com/reference/android/support/v4/widget/SwipeRefreshLayout.html
According to Android docs at the above link,
This layout should be made the parent of the view that will be refreshed as a result of the gesture and can only support one direct child.
If the ListView is the 1st direct child of the SwipeRefreshLayout, refresh won't be triggered before scrolling back to the top of the ListView. You don't need to do anything in onScroll().

How to implement scroll in list view to implement pagination?

I am building an application like techcrunch.
I am fetching data from server in JSON format and displaying the data in list view like article title,author name and image.
I have applied pagination means when user scroll more articles load in a list view. My pagination works fine but there is an issue in the scroll function as the fresh or new data loads the scroll dose not aligns with the data.
To clarify more in simple words my scroll-er goes at the top of the page when i am actually scrolling down
this is my code :
listView.setOnScrollListener(new AbsListView.OnScrollListener()
{
#Override
public void onScrollStateChanged(AbsListView absListView, int i)
{
}
#Override
public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount)
{
int lastItem = firstVisibleItem + visibleItemCount;
if(lastItem == totalItemCount){
if (mPreLast != lastItem)
{
mPreLast = lastItem;
onStart();
}
}
}
});`

You can use:
listView.setSelectionFromTop(newPosition, 0);
With this method you can set the position to a ListView, using the first parameter as the new position on the list, and the second parameter can be used to set the distance from the top

List views do not scroll smoothly

I have two list views. I need to scroll one list view automatically
when the other list view is scrolled. both list views should have this ability
i implemented the onScrollListner in both listviews
for listview 1
#Override
public void onScroll(AbsListView view, int firstVisibleItem,
int visibleItemCount, int totalItemCount) {
if (l1.getChildAt(0) != null) {
Rect r = new Rect();
l1.getChildVisibleRect(l1.getChildAt(0), r, null);
l2.setSelectionFromTop(l1.getFirstVisiblePosition(), r.top);
}
}
for listview 2
#Override
public void onScroll(AbsListView view, int firstVisibleItem,
int visibleItemCount, int totalItemCount) {
if (l2.getChildAt(0) != null) {
Rect r = new Rect();
l2.getChildVisibleRect(l2.getChildAt(0), r, null);
l1.setSelectionFromTop(l2.getFirstVisiblePosition(), r.top);
}
}
I have 2 problems regarding this
1 - the lists do not scroll smoothly. (not like normall listview)
2 - I can only scroll both listviews using one list view.(when i scroll using l2
both get scrolled. but it does not work when i scroll using l1. both stay fixed)
Thanks in advance

It happened becoz you put listview inside listview :)
You can achieve you problem using this.
suppose L1 is inside L2 then
L1.setOnTouchListener(new OnTouchListener() {
#Override
public boolean onTouch(View arg0, MotionEvent arg1) {
if(arg1.getAction() == MotionEvent.ACTION_DOWN || arg1.getAction() == MotionEvent.ACTION_MOVE)
{
L2.requestDisallowInterceptTouchEvent(true);
}
return false;
}
});

It's your application so you could do whatever you want but I am confused with what you want to achieve. The sole idea of having two list views is to have separate representation of two different categories of data so that they can be accessed(scrolled or selected) separately.
If you have requirement of representing two categories of data that need to be displayed side by side as a list then you can have a list row with two columns.
something like this will work:
You can populate these two rows with different kind of data and this can be scrolled together.

I found out a different way to get the same result. I remove my two list views and replaced it
with a grid view with two columns. this way i can scroll both without implementing onScrollListner and i can even use the custom adapter i used for the two listviews.

android: simultaneously scrolling horizontal listView

Consider I have two Horizontal ListView as shown below:
list1
list2
I want to know if it is possible to make the second list (list2) view scroll horizontally simultaneously along with the scroll of first list (list1).....
That is when I scroll list1 (horizontal), even list2 must scroll by the same offset...
Is this possible, if yes, please do help...
![link to image]: https://picasaweb.google.com/109389839906668906213/January132012#5697019272538269218

You can do that - just create such layout and use scroll events:
list1.setOnScrollListener(new OnScrollListener() {
public void onScrollStateChanged(AbsListView view, int scrollState) {
// TODO Auto-generated method stub
}
public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) {
list2.setSelectionFromTop(firstVisibleItem, list1.getChildAt(0).getTop());
}
});
Some explanation:
Better use list.setSelectionFromTop() than list.scrollTo() - because first visible item of first list can be shown partially.
list1.getChildAt(0).getTop() - is construction for getting value of X coordinate of first visible item.

As There is no HorizontalListView in Android, you must having another adapter view, anyway implement following:
list1.setOnItemSelectedListener(new OnItemSelectedListener()
{
public void onItemSelected(AdapterView adapterView adapterView, View view, int position, long id){
list2.setSelection(position);
}
});

Binding onScrolling listener to the android ListView

just wanted to ask is there a possibility to bind some listener to the ListView scroll event.
What I would like to achieve is that once ListView have been scrolled to the bottom I would like to ask server for more data if any is there.
I know that there is a function like: getLastVisiblePosition() but I assume it must bu used in some kind of listener in order to compare with currently last visible position, am I right ?
cheers,
/Marcin

Just to extrapolate on TomTo's answer, some thoughts on how you might do this (theoretical, I haven't tried this in practice):
ListView lv = (ListView)findViewById(R.id.list_view);
lv.setOnScrollListener(new OnScrollListener() {
#Override
public void onScroll(AbsListView view, int firstVisibleItem,
int visibleItemCount, int totalItemCount) {
//Check if the last view is visible
if (++firstVisibleItem + visibleItemCount > totalItemCount) {
//load more content
}
}
});
Since firstVisibleItem is returns an index (0-based), I increment by one to get the actual item number. Then, if that, plus the number of visible items, is greater than the total number of items, then in theory the last view should be visible. Shouldn't be a problem, but keep in mind this isn't called till the scrolling is finished.

used
if (++visibleItemCount > totalItemCount)
instead
if (++firstVisibleItem + visibleItemCount > totalItemCount)

AbsListView.OnScrollListener ?