Stack Overflow
Stack Overflow

Questions tagged [convertview]

ConvertView represents one of the parameters of the `getView` method of various Android adapters, often used to improve the performance of that adapter.

The convertView is a parameter in the getView method of all Android adapters. This convertView represents a recycled row view(if it is not null) which should always be used in the getView method to avoid the costly creation of objects every time the adapter is required to supply a row view from its getView method. A typical use pattern of the convertView in the getView method is:

  • check if the convertView is null.
  • if the convertView is null then the getView method must build the entire row view as there is no recycled view available.
  • if the convertView is not null then the getView method is supplying a recycled view on which the only needed actions are to setup the correct data/information.

More information about the convertView importance and use can be found in the Google I/O video about Android performance.

83 questions
3
votes
3 answers

Android BaseAdapter: convertView null on getView() re-entry

I am building a ListView with sections according to the technique described at http://bartinger.at/listview-with-sectionsseparators/ . But I would like to extend it by reusing convertView for the non-section items. However, I am finding that the…
Marc
  • 145
  • 1
  • 3
  • 11
2
votes
1 answer

Android, how to pass view and viewgroup parameters

I want to change the background color of one of my views in my listview myListView.getView(int position, View convertView, ViewGroup parent).setBackgroundColor(0x00FFE303); I know what position is - this will be my index of the arrayadapter, but I…
CQM
  • 42,592
  • 75
  • 224
  • 366
2
votes
1 answer

What is a convert view in adapter? And how it's works?

I can't understand what is a convert view.. Specifically, when does the program enter if condition and when else condition? public View getView(final int position, View convertView, ViewGroup parent) { final ViewHolder holder; …
Meet
  • 164
  • 2
  • 11
2
votes
1 answer

The difference between the two different signature of the methods of inflate

Im having a customized ArrayAdapter for a spinner in my app. Here's the code for its getDropDownView() method: @Override public View getDropDownView(int position, View convertView,ViewGroup parent) { View vista = convertView; …
Qing
  • 1,401
  • 2
  • 21
  • 41
2
votes
2 answers

initialize RelativeLayout in this getView, programmatic view generation

I am using a getView in an adapter where I am creating an imageview and making that equal to convertView where the view has already been initialized before. It contains image thumbnails, some of which represent videos. @Override public View…
CQM
  • 42,592
  • 75
  • 224
  • 366
2
votes
1 answer

convertView in custom adapter with multiple line views

I'm implementing custom adapter which handles multiple type of lines in a listview based on this (very useful) tutorial: http://logc.at/2011/10/10/handling-listviews-with-multiple-row-types/ Now, I thought I understood everything but one thing…
dsb
  • 2,347
  • 5
  • 26
  • 43
2
votes
0 answers

Detection on "scraping" a row view in ListView

Situation: I'm developing an app, which is some sort of photo frame app (there's 16 frames user can choose from), which consists of: ViewPager with maximum 5 ListView. (Off screen limit is set to 1, so we can assume only 3 ListViews will be in…
Chor Wai Chun
  • 3,226
  • 25
  • 41
2
votes
0 answers

Android,Using ConvertView in Heterogeneous List Adapters?

Docs say: ... Heterogeneous lists can specify their number of view types, so that this View is always of the right type (see getViewTypeCount() and getItemViewType(int)). I tried this way to create Heterogeneous List Adapters and I had no…
Student Student
  • 960
  • 2
  • 14
  • 24
2
votes
0 answers

group view disappear in expandable list view

I have an Expandable list view that contain a list view when after a certain number of rows I add other custom view. the problem is that when a try to expand the group for the 2nd time it disappear. thank's in advance. this is the code I wrote on…
Shalom Melamed
  • 299
  • 1
  • 4
  • 13
2
votes
2 answers

Nullpointer Exception by FindViewById in Android

Hey guys today I started to develop my own little alarmclock app. But now I've got a problem, and I'm searching for three hours and couldn't solve it. When I try to implement a listview with a custom design for each row, i get a…
jennymo
  • 1,450
  • 1
  • 18
  • 43
2
votes
1 answer

Listview with or without convertview == null

I have a dilemma using if (convertview==null){ (my code) } or not. Without this piece of code, my listview is not very fast, it locks for a few ms sometimes and you can easy notice this in use. It just doesn't work how its meant to work. But when…
Jasper
  • 2,389
  • 4
  • 25
  • 40
1
vote
4 answers

Problems when I use convertView, problems when I don't

I have a ListView which contains an ImageView and a TextView. I'm subclassing ArrayAdapter so that I can load an image from the internet, via a subclassed AsyncTask. All good so far. The problem is that if I try to use convertView, I have a problem…
John McCollum
  • 5,162
  • 4
  • 34
  • 50
1
vote
0 answers

adapterview inside adapterview & convertview

I have an adapterview (listview) and each contains some views including another adapterview(custom horizontal listview) All the convert views look fine, I got convert from the listview's adapter when I scroll vertically and convert from the…
vieux
  • 23,887
  • 3
  • 26
  • 26
1
vote
0 answers

Convert View inconsistency

Extended baseadapter using convertview's recycle logic causes list items TextView setText method to be called twice (overlaying text) in listview after scrolling view off screen and then back. Inflating convertview each time getview is called…
Robert Goodrick
  • 190
  • 1
  • 11
1
vote
1 answer

ListView element's sub element is repeating after a certain position

I have a listView which is working/displaying some data as Title and subtitle ,all is working fine but whenever I scroll up the list or the convertView recycles, the subtitle of last element get repeated while the Title is not, whats the issue.. …
sam
  • 113
  • 1
  • 9
1
2
3 4 5 6