问题
I have an ExpandableListView; the single item (group item) of the list has a FrameLayout that contains a ToggleButton. I did this in order to increase the button's touch area. I use the button to expand the child view of the group item it belongs to.
There can't be two checked buttons at a time, because when one gets checked, the previous one that was checked gets unchecked.
Now, the first time I click on the button of an item, it toggles alright; when, after that, I click on the one of another item, the button that toggles is the one at position "position of clicked button" +1.
If, however, I clicked on the last item's button, the button that will get toggled is the one at position "position of currently toggled button" +1 (this means that if I first toggle item 1, then click on the last item's button, item 2 will toggle; clicking again on the last one will toggle item 3, then item 4, item 5 and so on until, finally, the last item will toggle).
here's the adapter's code:
public class CustomList extends BaseExpandableListAdapter {
private final Activity context;
public List<Item> names;//Item is a custom object
public boolean[] buttons;
public int lastChecked;
private final int imageId = R.drawable.item1;
private ExpandableListView list;
public CustomList(Activity context, List<Item> names, ExpandableListView theListView) {
this.context = context;
this.names = names;
this.buttons = new boolean[names.size()];
this.lastChecked = -1;
this.list = theListView;
}
private static class GroupHolder {
TextView txtTitle;
TextView txtData;
ImageView imageView;
ToggleButton toggle;
FrameLayout frame;
}
public View getGroupView(final int position, boolean isExpanded, View convertView, ViewGroup parent) {
GroupHolder holder;
if (convertView == null) {
LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
convertView = inflater.inflate(R.layout.list_single, null);
holder = new GroupHolder();
holder.txtTitle = (TextView) convertView.findViewById(R.id.text);
holder.txtData = (TextView) convertView.findViewById(R.id.numberOfFiles);
holder.imageView = (ImageView) convertView.findViewById(R.id.img);
holder.toggle = (ToggleButton) convertView.findViewById(R.id.toggle);
holder.frame = (FrameLayout) convertView.findViewById(R.id.frame);
holder.frame.setOnTouchListener(new OnTouchListener() {
public boolean onTouch(View v, MotionEvent event) {
if(event.getAction() == MotionEvent.ACTION_UP) {
if(lastChecked != -1) {//if there's a checked button
buttons[lastChecked] = !buttons[lastChecked];//uncheck it
if(position == lastChecked)//if I clicked on the last checked button
lastChecked = -1;//there's no checked button
else {
buttons[position] = !buttons[position];//check the button
lastChecked = position;//and set it as the last checked one
}
notifyList();
}
return false;
}
});
convertView.setTag(holder);
} else {
holder = (GroupHolder) convertView.getTag();
}
holder.txtTitle.setText(names.get(position).getName());
holder.txtData.setText(names.get(position).getData());
holder.imageView.setImageResource(imageId);
holder.toggle.setChecked(buttons[position]);
if(holder.toggle.isChecked()) {
if(Build.VERSION.SDK_INT <= Build.VERSION_CODES.HONEYCOMB_MR2)
list.expandGroup(position);
else
list.expandGroup(position, true);
} else {
list.collapseGroup(position);
}
return convertView;
}
private static class ChildHolder {
TextView details;
TextView send;
TextView other;
}
public View getChildView(final int groupPosition, int childPosition, boolean isLastChild, View convertView, ViewGroup parent) {
ChildHolder holder;
if (convertView == null) {
LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
convertView = inflater.inflate(R.layout.list_child, null);
holder = new ChildHolder();
holder.details = (TextView) convertView.findViewById(R.id.details);
holder.send = (TextView) convertView.findViewById(R.id.send);
holder.other = (TextView) convertView.findViewById(R.id.other);
convertView.setTag(holder);
} else {
holder = (ChildHolder) convertView.getTag();
}
holder.details.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
buttons[lastChecked] = !buttons[lastChecked];//uncheck the only checked button (it always exists at this point)
lastChecked = -1;//there's no checked button
notifyList();
//*call some method in the main activity*
}
});
holder.send.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
buttons[lastChecked] = !buttons[lastChecked];//uncheck the only checked button (it always exists at this point)
lastChecked = -1;//there's no checked button
notifyList();
//*call some method in the main activity*
}
});
holder.other.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
buttons[lastChecked] = !buttons[lastChecked];//uncheck the only checked button (it always exists at this point)
lastChecked = -1;//there's no checked button
notifyList();
//*call some method in the main activity*
}
});
return convertView;
}
public void notifyList() {
this.notifyDataSetChanged();
}
As you can see, in the getGroupView, a child item gets expanded or collapsed depending on the value of the item in the boolean array that corresponds to the position of its view in the list. I call notifyDataSetChanged() to update the list.
in the main activity, I set the onGroupClickListener to the ExpandableListView and return true in the onGroupClick in order to not expand/collapse the child views when clicking on the group items (since I use the ToggleButtons for this).
回答1:
Ok, it was a very lame error. I had to set the OnTouchListener for the FrameLayout every time getGroupView was called, not only the first time. So the right code of the method is this:
public View getGroupView(final int position, boolean isExpanded, View convertView, ViewGroup parent) {
GroupHolder holder;
if (convertView == null) {
LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
convertView = inflater.inflate(R.layout.list_single, null);
holder = new GroupHolder();
holder.txtTitle = (TextView) convertView.findViewById(R.id.text);
holder.txtData = (TextView) convertView.findViewById(R.id.numberOfFiles);
holder.imageView = (ImageView) convertView.findViewById(R.id.img);
holder.toggle = (ToggleButton) convertView.findViewById(R.id.toggle);
holder.frame = (FrameLayout) convertView.findViewById(R.id.frame);
convertView.setTag(holder);
} else {
holder = (GroupHolder) convertView.getTag();
}
holder.txtTitle.setText(names.get(position).getName());
holder.txtData.setText(names.get(position).getData());
holder.imageView.setImageResource(imageId);
holder.frame.setOnTouchListener(new OnTouchListener() {
public boolean onTouch(View v, MotionEvent event) {
if(event.getAction() == MotionEvent.ACTION_UP) {
if(lastChecked != -1) {//if there's a checked button
buttons[lastChecked] = !buttons[lastChecked];//uncheck it
if(position == lastChecked)//if I clicked on the last checked button
lastChecked = -1;//there's no checked button
else {
buttons[position] = !buttons[position];//check the button
lastChecked = position;//and set it as the last checked one
}
notifyList();
}
return false;
}
});
holder.toggle.setChecked(buttons[position]);
if(holder.toggle.isChecked()) {
if(Build.VERSION.SDK_INT <= Build.VERSION_CODES.HONEYCOMB_MR2)
list.expandGroup(position);
else
list.expandGroup(position, true);
} else {
list.collapseGroup(position);
}
return convertView;
}
来源：https://stackoverflow.com/questions/23569860/expandablelistview-wrong-groupposition-returned-if-theres-an-expanded-childvie