Saving a position in a ListView after calling notifyDataSetChanged

Question

I use OnScrollListener to dynamically add items to the ListView when the user scrolls down. After adding data to the adapter and calling notifyDataSetChanged, although the ListView returns to the top. Ideally, I would like to keep the position in a ListView. Any thoughts on how I should do this?

Answer 1

Could this be what you want?

// save index and top position int index = mList.getFirstVisiblePosition(); View v = mList.getChildAt(0); int top = (v == null) ? 0 : v.getTop(); // notify dataset changed or re-assign adapter here // restore the position of listview mList.setSelectionFromTop(index, top); 

EDIT 09/28/2017:

The API has changed quite a bit since 2015. This is similar, but now it will be:

 // save index and top position int index = mList.FirstVisiblePosition; //This changed View v = mList.getChildAt(0); int top = (v == null) ? 0 : v.Top; //this changed // notify dataset changed or re-assign adapter here // restore the position of listview mList.setSelectionFromTop(index, top); 

Answer 2

Situation:

When you install the adapter in your list, it updates its status. Thus, it usually scrolls automatically.

Decision:

Assign an adapter to listview if it does not have one, otherwise update only the dataset of the assigned adapter, and do not reinstall it in the list.

A detailed guide is explained at the following link:

Android ListView: keep your scroll position when updating

Good luck

Answer 3

I implemented postDelayed and I started to flicker when upgrading. I was looking for something else and found out that I was doing something wrong. Basically, I don't have to create a new adapter every time I want to change the data. I ended it up like this and it works:

 //goes into your adapter public void repopulateData(String[] objects) { this.objects = null; this.objects = objects; notifyDataSetChanged(); } //goes into your activity or list if (adapter == null) { adapter = new Adapter(); } else { adapter.repopulateData((String[])data); } 

Hope this helps.

Answer 4

I use

listView.getFirstVisiblePosition

to save the last visible position.

Answer 5

Switch to list transcription mode.

Answer 6

try it

  boolean first=true; protected void onPostExecute(Void result) { if (first == true) { listview.setAdapter(customAdapter); first=false; } else customAdapter.notifyDataSetChanged(); } 

Answer 7

Here is the code:

 // Save the ListView state (= includes scroll position) as a Parceble Parcelable state = listView.onSaveInstanceState(); // eg set new items listView.setAdapter(adapter); // Restore previous state (including selected item index and scroll position) listView.onRestoreInstanceState(state);