Handling double click events on ListBox items in C#
Solution 1
Tried creating a form with a ListBox with MouseDown and DoubleClick events. As far as I can see, the only situation, when DoubleClick won't fire, is if inside the MouseDown you call the MessageBox.Show(...). In other cases it works fine.
And one more thing, I don't know for sure, if it is important, but anyway. Of course, you can get the index of the item like this:
int index = this.listBox1.IndexFromPoint(e.Location);
But this way is fine as well:
if (listBox1.SelectedItem != null)
...
Solution 2
Thank you for all replies. It now works. I solved it, like 26071986 said, with handling double click in the MouseDown handler by checking if e.Clicks is 1. If so, I call DoDragDrop, if not, I call the method that handles double click.
private void MouseDown_handler(object sender, MouseEventArgs e)
{
var listBox = (ListBox) sender;
if (e.Clicks != 1)
{
DoubleClick_handler(listBox1.SelectedItem);
return;
}
var pt = new Point(e.X, e.Y);
int index = listBox.IndexFromPoint(pt);
// Starts a drag-and-drop operation with that item.
if (index >= 0)
{
var item = (listBox.Items[index] as MyObject).CommaDelimitedString();
listBox.DoDragDrop(item, DragDropEffects.Copy | DragDropEffects.Move);
}
}
Solution 3
Works for me, so I assume there might be something about the items in the list (custom? intercepting the event?) or the event is not properly wired up.
For example try this (complete Form1.cs):
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Windows.Forms;
namespace WindowsFormsApplication1 {
public class MyObject {
public MyObject(string someValue) {
SomeValue = someValue;
}
protected string SomeValue { get; set; }
public override string ToString() {
return SomeValue;
}
}
public partial class Form1 : Form {
public Form1() {
InitializeComponent();
var list = new List<MyObject> {
new MyObject("Item one"), new MyObject("Item two")
};
listBox1.DataSource = list;
}
private void listBox1_DoubleClick(object sender, EventArgs e) {
Debug.WriteLine("DoubleClick event fired on ListBox");
}
}
}
With the designer source file (Form1.Designer.cs) containing this:
private void InitializeComponent() {
this.listBox1 = new System.Windows.Forms.ListBox();
... // left out for brevity
this.listBox1.DoubleClick += new System.EventHandler(this.listBox1_DoubleClick);
As a test, create a new Forms base application through the templates, then add just the ListBox and define a class MyObject. See whether you observe the same or a different behavior.
Solution 4
Here's what I used in the MouseDoubleClick event.
private void YourMethodForDoubleClick(object sender, MouseButtonEventArgs e)
{
Type sourceType = e.OriginalSource.GetType();
if (sourceType != typeof(System.Windows.Controls.TextBlock)
&& sourceType != typeof(System.Windows.Controls.Border))
return;
//if you get here, it's one of the list items.
DoStuff();
...
}
Comments
-
Hans Espen almost 2 years
I am trying to do something when double clicking an item in a ListBox. I have found this code for doing that
void listBox1_MouseDoubleClick(object sender, MouseEventArgs e) { int index = this.listBox1.IndexFromPoint(e.Location); if (index != System.Windows.Forms.ListBox.NoMatches) { MessageBox.Show(index.ToString()); //do your stuff here } }
However, when i click on an item, the event isn't fired. The event is fired if i click in the ListBox below all the items.
I set the DataSource property of the
ListBox
toIList<MyObject>
.Any ideas?