I'm new to Android and Java. I was wondering if there is a way to find the position of a ListView item by its value.
For example:
If I have an item in my ListView that displays the string "Product 1108" How would I get the position of "Product 1108"?
private void updateListView() {
final ListView lvCheckList = (ListView) findViewById(R.id.lvCheckList);
Map<String, ?> keys = checkListData.getAll();
ArrayList<String> checkListStrings = new ArrayList<String>();
for (Map.Entry<String, ?> entry : keys.entrySet()) {
if (entry.getKey().equals(currentList + entry.getValue())) {
checkListStrings.add((String) entry.getValue());
}
if (entry.getKey().equals(currentList + entry.getValue() + "Checked")) {
//set Item to checked / unchecked
}
}
ArrayAdapter<String> checkListArrayAdapter = new ArrayAdapter<String>(
this, android.R.layout.simple_list_item_checked,
checkListStrings);
lvCheckList.setAdapter(checkListArrayAdapter);
}
This code gets the the the items stored in SharedPreferences and displays them in the ListView. Don't ask me why it works, it just does.
Now see this line:
if (entry.getKey().equals(currentList + entry.getValue() + "Checked")) {
//set Item to checked / unchecked
}
What I want to happen here is to set the list item to either checked or unchecked, but I don't think that it's possible because the listview has not been populated yet. So in the ArrayAdapter I need to sort through the items of the listview, find the item with whatever value I'm looking for, and get the position of that item so I can use this code:
lvCheckList.setItemChecked(position, value);
Hopefully this made sense.
If you have a BaseAdapter
you should have a something like an ArrayList
storing items, which you could use the indexOf(obj)
method on.
If you're using an ArrayAdapter
you could use getPosition(obj);
Here is an example of looping over an ArrayAdapter
(let me know if you use something else):
ArrayAdapter adapter = new YourCustomArrayAdapter();
for(int i = 0; i < adapter.getCount(); i++)
System.out.println(String.format("String \"%s\" has an index of %d", adapter.getItem(i), i);
This does not use the method getPosition()
because our loop feeds us a position that we get the item for.
You can do this
Toast.makeText(getApplicationContext, "The position of the clicked item is " + position, Toast.LENGTH_SHORT).show();
in the listview onItemClickListener()
that you will implement
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