在仍在添加项目的同时向每个listview项目添加onItemClickListener

Question

I'm not really sure how to explain this problem, but I'll do my best. I have an app that records sound and after you're done recording, you have to rename the file and then the file is added to listview in another activity.

I have tab layout, so adding files to listview is a little bit more complicated, here's how I do it:

Recording activity:

if (getParent() instanceof FileNameProvider) {
    ((FileNameProvider) getParent()).onNewFileName(newFileName);
}

Tab layout activity:

public void onNewFileName(Editable filename) {
    LocalActivityManager activityManager = getLocalActivityManager();
    getTabHost().setCurrentTabByTag("Library");
    RecordedLibrary recLib = (RecordedLibrary) activityManager.getActivity("Library");
    recLib.setFileName(filename);
}

And finally, I get the new filename in my library (listview) activity:

public void setFileName(final Editable filename) {
    Log.d("2", "Set filename from first activity " + filename);
}

So, everytime I set a filename, it's automatically added to listview with this code:

public void setFileName(final Editable filename) {
    Log.d("2", "Set filename from first activity " + filename);

    //LISTVIEW (declared globally)
    fileNames.add(filename.toString()); 
    listView = (ListView) findViewById (R.id.mainListView);
    listAdapter = new ArrayAdapter<String>(this, R.layout.simplerow, fileNames);
    listView.setAdapter(listAdapter);

Now what I want to do next is to also automatically add onItemClickListener for each item added. I know I could do this with switch statement like this:

switch (position){
    case 0:
        //code
        break;
}

But this isn't possible in my case because everytime I record a file, this file has a different path, since there's a different name. This is how I tried to do it:

listView.setOnItemClickListener(new OnItemClickListener() {

        @Override
        public void onItemClick(AdapterView<?> arg0, View arg1, int arg2,
            long arg3) {
            Toast toast = Toast.makeText(getApplicationContext(), filename, Toast.LENGTH_SHORT);
            toast.show();
        }

    });

This doesn't work either because everytime I add a new file to the listview, the filename variable changes, so this code works only as long as I only add one item to listview. As soon as I add the second item to listview, toast will show the second file's name no matter which item I click.

I hope everyone understand's the problem. Let me know if I should add any more info.

SOLUTION:

listView.setOnItemClickListener(new OnItemClickListener() {

        @Override
        public void onItemClick(AdapterView<?> arg0, View arg1, int arg2,
            long arg3) {
            Toast toast = Toast.makeText(getApplicationContext(), fileNames.get(arg2), Toast.LENGTH_SHORT);
            toast.show();
        }

    });

As you can see, I simply changed the 'filaname' to 'fileNames.get(arg2)', please see this answer for more details.

Answer 1

You should NOT create and set a new ListAdapter each and every time you set a file name.

Adapters should only be created once and attached to a ListView once per lifecycle, which is probably why the second time you add a file, only the second file name is being returned. You are overriding the previous Adapter and data each time you call setFileName .

Answer 2

You don't need to add an onClickListener to every object in your list. As you indicated above that you're use a seperate activity to house your ListView I would (1) make that activity extend ListActivity (2) use onListItemClick

@Override
protected void onListItemClick(ListView l, View v, int position, long id) {
    super.onListItemClick(l, v, position, id);

}

This way if you keep track of which file is added in which order (above you mention you're using an ArrayList to store file names) you could use the position or id value (depending on what kind of adapter is backing your list) to retrieve the file name. You can play around with which collection works best for retrieving the file data (though the array list probably works fine if you're adding and removing these values in a predictable order).

You can also do this using the onItemClickListener you have in place. Arg2 is the position of the item in the list. Just take that value and get the file you need from the ArrayList storing the file extention.