Change ListView background - strage behaviour
- by Beasly
Hi again,
I have a problem with changing the background of a view in a ListView.
What I need:
Change the background image of a row onClick()
What actually happens:
The background gets changed (selected) after pressing e.g. the first entry. But after scrolling down the 8th entry is selected too.
Scroll back to the top the first isn't selected anymore. The second entry is selected now.
Continue scrolling and it continues jumping...
What i'm dong in the Code:
I have channels, and onClick() I toggle an attribute of channel boolean selected
and then I change the background.
I'm doing this only onClick() thats why I don't get why it's actuelly happening on other entries too.
One thing I notices is: It seems to be only the "drawing"-part because the item which get selected "by it self" has still the selected value on false
I think it seems to have something to do with the reuse of the views in the custom ListAdapters getView(...)
Code of onClick() in ListActivity:
@Override
protected ViewHolder createHolder(View v) {
// createHolder will be called only as long, as the ListView is not
// filled
TextView title = (TextView) v
.findViewById(R.id.tv_title_channel_list_adapter);
TextView content = (TextView) v
.findViewById(R.id.tv_content_channel_list_adapter);
ImageView icon = (ImageView) v
.findViewById(R.id.icon_channel_list_adapter);
if (title == null || content == null || icon == null) {
Log.e("ERROR on findViewById",
"Couldn't find Title, Content or Icon");
}
ViewHolder mvh = new MyViewHolder(title, content, icon);
// We make the views become clickable
// so, it is not necessary to use the android:clickable attribute in
// XML
v.setOnClickListener(new ChannelListAdapter.OnClickListener(mvh) {
public void onClick(View v, ViewHolder viewHolder) {
// we toggle the enabled state and also switch the the
// background
MyViewHolder mvh = (MyViewHolder) viewHolder;
Channel ch = (Channel) mvh.data;
ch.setSelected(!ch.getSelected()); // toggle
if (ch.getSelected()) {
v.setBackgroundResource(R.drawable.row_blue_selected);
} else {
v.setBackgroundResource(R.drawable.row_blue);
}
// TESTING
Log.d("onClick() Channel", "onClick() Channel: "
+ ch.getTitle() + " selected: " + ch.getSelected());
}
});
return mvh;
}
Code of getView(...):
@Override
public View getView(int position, View view, ViewGroup parent) {
ViewHolder holder;
// When view is not null, we can reuse it directly, there is no need
// to reinflate it.
// We only inflate a new View when the view supplied by ListView is
// null.
if (view == null) {
view = mInflater.inflate(mViewId, null);
// call own implementation
holder = createHolder(view);
// TEST
// we set the holder as tag
view.setTag(holder);
} else {
// get holder back...much faster than inflate
holder = (ViewHolder) view.getTag();
}
// we must update the object's reference
holder.data = getItem(position);
// call the own implementation
bindHolder(holder);
return view;
}
I really would appreciate any idea how to solve this! :)
If more information is needed please tell me.
Thanks in advance!
