How to get all checked items from a ListView?
Solution 1:
The other answers using SparseBooleanArray
are nearly correct, but they are missing one important thing: SparseBooleanArray.size()
will sometimes only return the count of true
values. A correct implementation that iterates over all the items of the list is:
SparseBooleanArray checked = list.getCheckedItemPositions();
for (int i = 0; i < list.getAdapter().getCount(); i++) {
if (checked.get(i)) {
// Do something
}
}
Solution 2:
I solved my case with this:
public class MyAdapter extends BaseAdapter{
public HashMap<String,String> checked = new HashMap<String,String>();
....
public void setCheckedItem(int item) {
if (checked.containsKey(String.valueOf(item))){
checked.remove(String.valueOf(item));
}
else {
checked.put(String.valueOf(item), String.valueOf(item));
}
}
public HashMap<String, String> getCheckedItems(){
return checked;
}
}
To set an element is checked:
public class FileBrowser extends Activity implements OnClickListener{
private ListView list;
...
list.setOnItemClickListener(new OnItemClickListener(){
@Override
public void onItemClick(AdapterView<?> parent, View view, int item,
long id) {
BrowserAdapter bla = (BrowserAdapter) parent.getAdapter();
bla.setCheckedItem(item);
}
});
Then to get the checked items from outside the class..
MyAdapter bAdapter;
Iterator<String> it = bAdapter.getCheckedItems().values().iterator();
for (int i=0;i<bAdapter.getCheckedItems().size();i++){
//Do whatever
bAdapter.getItem(Integer.parseInt(it.next());
}
Hope it can help someone.
Solution 3:
Jarett's answer is great, but this should be a bit faster, since it's only checking the elements in the sparse array that are present in the underlying array (only those can be true):
SparseBooleanArray checkedItemPositions = listView.getCheckedItemPositions();
final int checkedItemCount = checkedItemPositions.size();
for (int i = 0; i < checkedItemCount; i++) {
int key = checkedItemPositions.keyAt(i);
if (checkedItemPositions.get(key)) {
doSomething(key);
} else {
// item was in the sparse array, but not checked.
}
}
Pro tip: look at the source of SparseBooleanArray, it's a pretty simple class:
http://grepcode.com/file_/repository.grepcode.com/java/ext/com.google.android/android/4.0.3_r1/android/util/SparseBooleanArray.java/?v=source