更新ListView上次单击的项目

Question

I have ListView which is customized to have a EditText box and a Button in it. The ListView displays text boxes as visible but the button as invisible . When the user clicks on an item in the ListView, the Button's made visible. I have written the following code for the ListView:

public void onItemClick(AdapterView<?> list, View view, int position, long id) {    
    view.findViewById(R.id.button).setVisibility(View.VISIBLE);
}

The above code functions in the case when the first item's Button and the second item's Button are visible.

My problem:
When the next item in the ListView is clicked, the Button from the previous item should become invisible as the current item's Button becomes visible. So how do I update the view of the previous item?

Answer 1

Store the previous row in a class variable:

View previous;
...

public void onItemClick(AdapterView<?> list, View view, int position, long id) {    
    if(previous != null)
        previous.setVisibility(View.INVISIBLE);

    // Set the current button to visible while saving it for the next click 
    previous = view.findViewById(R.id.button);
    previous.setVisibility(View.VISIBLE);
}

---

Addition from comments

You're right. The adapter's view recycling is affecting the other rows so let's extend whatever adapter you are using and override its getView() method:

public int selectedRow = -1;
...

@Override
public View getView(int position, View convertView, ViewGroup parent) {
    View view = super.getView(position, convertView, parent);

    // Here, either use findViewById() (slower) or the ViewHolder method (faster) to load the button:
    // Button button = ...

    if(position == selectedRow) 
        button.setVisibility(View.VISIBLE);
    else
        button.setVisibility(View.GONE);

    return view;
}

And in your onItemClick() method add a line like this:

adapter.selectedRow = position;

Answer 2

Attach a listener on the button instead of the listview itself. You could do it in the getview() method.