#DEPRECATED Please use RecyclerView instead.
Demonstrate how to put EidtText widget in ListView as an item.
com.aspsine.edittextinlistview.LineAdapter#getView()
@Override
public View getView(final int position, View convertView, final ViewGroup parent) {
final ViewHolder holder;
if (convertView == null) {
holder = new ViewHolder();
convertView = LayoutInflater.from(parent.getContext()).inflate(R.layout.item_line, parent, false);
holder.etLine = (EditText) convertView.findViewById(R.id.etLine);
convertView.setTag(holder);
} else {
holder = (ViewHolder) convertView.getTag();
}
final Line line = lines.get(position);
// step 1: remove android.text.TextWatcher added in step 5 to make sure android.text.TextWatcher
// don't trigger in step 2;
// why?
//
// note: When an object of a type is attached to an Editable,
// TextWatcher's methods will be called when the EidtText's text is changed.
//
// EditText use a ArrayList<TextWatcher> type object to store the listener, so we must
// make sure there's only one TextWatcher object in this list;
//
// Avoid triggering TextWatcher's method in step 2 we remove it at first time.
//
if (holder.etLine.getTag() instanceof TextWatcher) {
holder.etLine.removeTextChangedListener((TextWatcher) (holder.etLine.getTag()));
}
// step 2: set text and focus after remove android.text.TextWatcher(step 1);
holder.etLine.setHint(position + ".");
// set text
if (TextUtils.isEmpty(line.getText())) {
holder.etLine.setTextKeepState("");
} else {
holder.etLine.setTextKeepState(line.getText());
}
// set focus status
// why?
//
// note: ListView has a very elegant recycle algorithm. So views in ListView is not reliable.
// Especially in this case, EditText is an item of ListView. Software input window may cause
// ListView relayout leading adapter's getView() invoke many times.
// Above all if we change EditText's focus state directly in EditText level(not in Adapter).
// The focus state may be messed up when the particularly view reused in other position.
//
// So using data source control View's state is the core to deal with this problem.
if (line.isFocus()) {
if (!holder.etLine.isFocused()) {
holder.etLine.requestFocus();
}
CharSequence text = line.getText();
// reset cursor.
holder.etLine.setSelection(TextUtils.isEmpty(text) ? 0 : text.length());
} else {
if (holder.etLine.isFocused()) {
holder.etLine.clearFocus();
}
}
// step 3: set an OnTouchListener to EditText to update focus status indicator in data source
// why?
//
// in step 2, we know we must control view state through data source. We use OnTouchListener
// to watch the state change and update the data source when user move up fingers(ACTION_UP).
// We don't want to consume the touch event, simply return false in method onTouch().
holder.etLine.setOnTouchListener(new View.OnTouchListener() {
@Override
public boolean onTouch(View v, MotionEvent event) {
if (event.getAction() == MotionEvent.ACTION_UP) {
check(position);
// make cursor blink
if (!focus || !holder.etLine.isFocused()) {
holder.etLine.requestFocus();
holder.etLine.onWindowFocusChanged(true);
}
}
return false;
}
});
// step 4: set TextWatcher to EditText to listen text changes in EditText to updating the text in data source
// why?
//
// again, use data source to control view state.
// When user edit the text in one EditText item and scroll the ListView. The particularly EditText item will be
// reuse in adapter's getView(), this may lead text messed up in ListView.
// How to deal with this problem?
// Easy! We update the text in data source at the same time when user is editing. TextWatcher is the best way to
// do this.
final TextWatcher watcher = new SimpeTextWather() {
@Override
public void afterTextChanged(Editable s) {
if (TextUtils.isEmpty(s)) {
line.setText(null);
} else {
line.setText(String.valueOf(s));
}
}
};
holder.etLine.addTextChangedListener(watcher);
// step 5: Set watcher as a tag of EditText.
// so we can remove the same object which was setted to EditText in step 4;
// Make sure only one callback is attached to EditText
holder.etLine.setTag(watcher);
return convertView;
}
/**
* change focus status in data source
*/
private void check(int position) {
for (Line l : lines) {
l.setFocus(false);
}
lines.get(position).setFocus(true);
}
static class ViewHolder {
EditText etLine;
}
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