Develop Reference

Different components in different rows of an Android ListView

I am new to Android. I would like to create an Activity very similar to "Add event" part of Android Calendar app. To me it looks like a ListView with different components in each row. I could be wrong. If I am right, I still don't know how to add different components to each row of a ListView, e.g., EditText in one row, TextView in another row, etc. If this app is not ListView at all, if anybody can tell me how I can create something similar, I'd appreciate that a lot.

hello check this link it be helpful 1
listView with different component

First you have to learn how to implement a custom Adapter (see this tutorial: http://www.vogella.com/tutorials/AndroidListView/article.html#adapterown)
Then in your getView overriden method (you'll learn about it in the tutorial) you have to do something like this:
#Override
public View getView(int position, View convertView, ViewGroup parent) {
LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View rowView = null;
if (position == LAYOUT1_POSITION) //In this row you will place the layout named layout1
rowView = inflater.inflate(R.layout.rowLayout1, parent, false);
if (position == LAYOUT2_POSITION)
rowView = inflater.inflate(R.layout.rowLayout2, parent, false);
//Do similar for all your different layouts
return rowView;
}

ListView with two different list items

I would like to have a listView that the first list item will have a red background and the second will have black.Is that possible?And if yes,how will i create the custom list adapter?
thanks!!
|Black item|
|Red item|
|Black item|
|Red item|
|Black item|
etc.

You should Override getView in your arrayadapter. One of the parameters passed into this method is a position. So you can just do the position % 2 to determine if the row is even or odd. Depending on what you want to do you can change you can inflate two totally different layouts there.

When you have the public View getView(int position, View convertView, ViewGroup parent) method make it apply different style for each position %2 == 0. This way you can easily make those items differ from each other :)
I hope this helped.

here's the getView from my latest project's adapter. I've simplified it to highlight a couple of things: 1. that you can use whatever criteria you like to decide what kind of view will be returned, and 2. that you can use LayoutInflater.inflate to get any kind of view at all, whatever the case may be.
public View getView(final int position, View convertView, ViewGroup parent)
{
View v;
int n = itemList.get(position);
if (n < 0)
{
v = inflator.inflate(R.layout.layout1, null);
}
else if (n > 0)
{
v = inflator.inflate(R.layout.layout2, null);
}
else
v = inflator.inflate(R.layout.layout3, null);
return v;
}

Android - Recycling listview elements automatically?

I created a listview that has a custom SimpleCursorAdapter. I want to place a header in the first element in the list. 8 views fit on the screen at a time. When I scroll down to the ninth view, the header of the 1st element appears. At least I believe that is what is happening. I removed a button above the listview allowing all of the elements to appear on screen and only the first element had the header.
I believe I am forcing a new view to be inflated each time. I have read up a bit on convertview and it appears to be something that you have to implement manually.
#Override
public View newView(Context context, Cursor cursor, ViewGroup parent) {
final LayoutInflater inflater = LayoutInflater.from(context);
int position = cursor.getPosition();
View v;
v = inflater.inflate(R.layout.roster_lv_row_entry_with_header, parent, false);
if(position > 0)
v = inflater.inflate(R.layout.roster_lv_row_entry_no_header, parent, false);
return v;

You shoul override the (final int position, View convertView, ViewGroup parent) method in your adapter class, and
assign the convertView parameter a
new value (if necessary, but better just use it if it's the right type, and fill it with the proper data based on yourListData.get(position), where yourListData is e.g. a List<?> extension.)
then return it.

GridView with customs view

I don't know if it is possible, but actually I wouldn't see why not.
Can we do a grid view not just with ImageView but with a custom view.
I am trying to make a grid view of a view composed of an ImageView and a TextView.
I know that everything happens in my Adapter getView's function but I can't figure out how to do it.
public View getView(int position, View convertView, ViewGroup parent) {
View cases = findViewById(R.id.fileUnitLayout);
if (convertView == null) {
convertView = new View(mContext);
} else {
cases = convertView;
}
return cases;
}
My view has an id of R.id.fileUnitLayout. Let's say my inner TextView has an id of A and my inner ImageView has an id of B. How can I fill them ?
Thank you,

You should not need to override getView to accomplish this, necessarily. GridView is an AdapterView so you can provide an adapter that will display what you want via setAdapter
You could, for example, use SimpleAdapter to provide an xml file that is used for each grid view item.

ListView in ArrayAdapter order get's mixed up when scrolling

I have a ListView in a custom ArrayAdapter that displays an icon ImageView and a TextView in each row. When I make the list long enough to let you scroll through it, the order starts out right, but when I start to scroll down, some of the earlier entries start re-appearing. If I scroll back up, the old order changes. Doing this repeatedly eventually causes the entire list order to be seemingly random. So scrolling the list is either causing the child order to change, or the drawing is not refreshing correctly.
What could cause something like this to happen? I need the order the items are displayed to the user to be the same order they are added to the ArrayList, or at LEAST to remain in one static order. If I need to provide more detailed information, please let me know. Any help is appreciated. Thanks.

I was having similar issues, but when clicking an item in the custom list, the items on the screen would reverse in sequence. If I clicked again, they'd reverse back to where they were originally.
After reading this, I checked my code where I overload the getView method. I was getting the view from the convertedView, and if it was null, that's when I'd build my stuff. However, after placing a breakpoint, I found that it was calling this method on every click and on subsequent clicks, the convertedView was not null therefore the items weren't being set.
Here is an example of what it was:
public View getView(int position, View convertView, ViewGroup parent)
{
View view = convertView;
if (view == null)
{
LayoutInflater vi = (LayoutInflater) getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
view = vi.inflate(R.layout.listitemrow, null);
RssItem rssItem = (RssItem) super.getItem(position);
if (rssItem != null)
{
TextView title = (TextView) view.findViewById(R.id.rowtitle);
if (title != null)
{
title.setText(rssItem.getTitle());
}
}
}
return view;
}
The subtle change is moving the close brace for the null check on the view to just after inflating:
public View getView(int position, View convertView, ViewGroup parent)
{
View view = convertView;
if (view == null)
{
LayoutInflater vi = (LayoutInflater) getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
view = vi.inflate(R.layout.listitemrow, null);
}
RssItem rssItem = (RssItem) super.getItem(position);
if (rssItem != null)
{
TextView title = (TextView) view.findViewById(R.id.rowtitle);
if (title != null)
{
title.setText(rssItem.getTitle());
}
}
return view;
}
I hope this helps others who experience this same problem.

To further clarify the answer of farcats below in more general way, here is my explanation:
The vi.inflate operation (needed here for parsing of the layout of a row from XML and creating the appropriate View object) is wrapped by an if (view == null) statement for efficiency, so the inflation of the same object will not happen again and again every time it pops into view.
HOWEVER, the other parts of the getView method are used to set other parameters and therefore should NOT be included within the if (view == null) statement.
Similarily, in other common implementation of this method, some textView, ImageView or ImageButton elements need to be populated by values from the list[position], using findViewById and after that .setText or .setImageBitmap operations.
These operations must come after both creating a view from scratch by inflation and getting an existing view if not null.
Another good example where this solution is applied for BaseAdapter appears in BaseAdapter causing ListView to go out of order when scrolled

The ListView reuses view objects when you scroll. Are you overriding the getView method? You need to make sure you set each property for every view, don't assume that it will remember what you had before. If you post that method, someone can probably point you at the part that is incorrect.

I have a ListView, AdapterView and a View (search_options) that contains EditText and 3 Spinners. ListView items are multiple copies of (search_options) layout, where user can add more options in ListView then click search to send sql query built according to users options.
I found that convertView mixing indecies so I added a global list (myViews) in activity and passed it to ArrayAdapter. Then in ArrayAdapter (getView) I add every newly added view to it (myViews).
Also on getView instead of checking if convertView is null, I check if the global list (myViews) has a view on the selected (position).. It totally solved problems after losing 3 days reading the internet!!
1- on Activity add this:
Map<Integer, View> myViews = new HashMap<>();
and then pass it to ArrayAdapter using adapter constructor.
mSOAdapter = new SearchOptionsAdapter(getActivity(), resultStrs, myViews);
2- on getView:
#Override
public View getView(int position, View convertView, ViewGroup parent) {
View view;
ViewHolder viewHolder;
if (!myViews.containsKey(position)) {
viewHolder = new ViewHolder();
LayoutInflater inflater = LayoutInflater.from(getContext());
view = inflater.inflate(R.layout.search_options, parent, false);
/// ...... YOUR CODE
myViews.put(position, view);
FontUtils.setCustomFontsIn(view, getContext().getAssets());
}else {
view = myViews.get(position);
}
return view;
}
Finally no more mixing items...