Clear SingleChoice ListView selection

问题

Is there a way to clear the selected item in a ListView?

The ListView is defined like this:

<ListView
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:minHeight="50dp"
    android:id="@+id/example_list"
    android:layout_weight="2"
    android:choiceMode="singleChoice"/>

And is filled using a custom Adapter.

The selected item is highlighted using a Selector:

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
  <item android:state_pressed="true" >
    <shape>
      <gradient
       android:startColor="#3E5260"
         android:endColor="#3E5260"
         android:angle="270" />
    </shape>
  </item>
  <item android:state_activated="true">
    <shape>
      <gradient
       android:startColor="#3E5260"
         android:endColor="#3E5260"
         android:angle="270" />
    </shape>
  </item>
</selector>

Now what I really have is 2 ListViews in a single activity and when an item is
selected in one ListView I want to deselect the item in the other ListView.

Both ListViews raise the following handler when an item is clicked:

void DeviceList_Click(object sender, EventArgs e)
{
    //easy enough to check which ListView raised the event
    //but then I need to deselect the selected item in the other listview
}

I've tried things like:

exampleList.SetItemChecked(exampleList.SelectedItemPosition, false);

and

exampleList.SetSelection(-1);

But that does not seem to work.

回答1:

Using listView.SetItemChecked(-1, true); works fine here.

Here is my Activity I tested with:

SetContentView(Resource.Layout.Main);
var listView = FindViewById<ListView>(Resource.Id.listView);
_listAdapter = new CustomListAdapter(this);
listView.Adapter = _listAdapter;

var button = FindViewById<Button>(Resource.Id.removeChoice);
button.Click += (sender, args) => listView.SetItemChecked(-1, true);

Main.axml:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 
  xmlns:android="http://schemas.android.com/apk/res/android"
  android:orientation="vertical"
  android:layout_width="fill_parent"
  android:layout_height="fill_parent"
    >
  <ListView
    android:id="@+id/listView"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:choiceMode="singleChoice"
  />
  <Button
    android:id="@+id/removeChoice"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:text="remove choice"
    />
</LinearLayout>

回答2:

Use clearChoices() to clear the checked state of all items in a ListView

回答3:

Its works simple for me:

ListView listView = (ListView) findViewById(R.id.idMyListView);
         listView.clearFocus();

回答4:

It's an old question, but just in case someone else needs it in the future, based on @Cheesebaron answer, here's what I did:

On each ListViews' OnItemClickListener set the other's list checked item to false:

list1.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        public void onItemClick(AdapterView<?> parent, View view, int pos, long id) {
            list2.setItemChecked(list2.getSelectedItemPosition(), false);
        }
});

This implementation is in Java, but if you get the logic here you can implement it in C# as well. Hope this helps.

回答5:

For CHOICE_MODE_SINGLE / singleChoice

int v = listView.getCheckedItemPosition();
if (v >= 0)
    listView.setItemChecked(v, false);

来源：https://stackoverflow.com/questions/15081274/clear-singlechoice-listview-selection