Windows Forms Controls on ScrollableControl and Events
I noticed that the Click event or other control behavior is not always triggered when the control contained in the ScrollableControl (Panel, etc.) is clicked.
If a click on a control has no focus and is only partially visible, it scrolls into view. This is what I expect, however the Click event does not fire, otherwise the control behavior does not happen.
If the control already has focus and is only partially visible, events are fired.
The checkbox is a scroll in the viewing field, the check state does not change. CheckedListBox - Scrolls and the selected item is not selected. TreeView - Scrolling in the view, node click is not selected. Button - scrolls in view, no click event is raised.
To reproduce this, you can do the following:
- Add any of the above controls to the Group
- Add event handler for Click, SelectedItemChanged, etc.
- Resize the form so that the scroll bars are visible in the panel
- Scroll the panel so that one of the controls is partially visible.
- Click a partially visible control
Is there a way to ensure that the events are fired?
David
This worked for me.
Code in Form1.Designer.cs:
namespace WindowsFormsApplication1
{
partial class Form1
{
/// <summary>
/// Required designer variable.
/// </summary>
private System.ComponentModel.IContainer components = null;
/// <summary>
/// Clean up any resources being used.
/// </summary>
/// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
protected override void Dispose(bool disposing)
{
if (disposing && (components != null))
{
components.Dispose();
}
base.Dispose(disposing);
}
#region Windows Form Designer generated code
/// <summary>
/// Required method for Designer support - do not modify
/// the contents of this method with the code editor.
/// </summary>
private void InitializeComponent()
{
this.panel1 = new System.Windows.Forms.Panel();
this.textBox2 = new System.Windows.Forms.TextBox();
this.textBox1 = new System.Windows.Forms.TextBox();
this.panel1.SuspendLayout();
this.SuspendLayout();
//
// panel1
//
this.panel1.AutoScroll = true;
this.panel1.Controls.Add(this.textBox2);
this.panel1.Controls.Add(this.textBox1);
this.panel1.Location = new System.Drawing.Point(86, 75);
this.panel1.Name = "panel1";
this.panel1.Size = new System.Drawing.Size(176, 70);
this.panel1.TabIndex = 0;
//
// textBox2
//
this.textBox2.Location = new System.Drawing.Point(109, 17);
this.textBox2.Name = "textBox2";
this.textBox2.Size = new System.Drawing.Size(100, 20);
this.textBox2.TabIndex = 1;
this.textBox2.Click += new System.EventHandler(this.textBox2_Click);
//
// textBox1
//
this.textBox1.Location = new System.Drawing.Point(3, 17);
this.textBox1.Name = "textBox1";
this.textBox1.Size = new System.Drawing.Size(100, 20);
this.textBox1.TabIndex = 0;
this.textBox1.Click += new System.EventHandler(this.textBox1_Click);
//
// Form1
//
this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
this.ClientSize = new System.Drawing.Size(493, 271);
this.Controls.Add(this.panel1);
this.Name = "Form1";
this.Text = "Form1";
this.panel1.ResumeLayout(false);
this.panel1.PerformLayout();
this.ResumeLayout(false);
}
#endregion
private System.Windows.Forms.Panel panel1;
private System.Windows.Forms.TextBox textBox2;
private System.Windows.Forms.TextBox textBox1;
}
}
Code in Form1.cs:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
namespace WindowsFormsApplication1
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void textBox1_Click(object sender, EventArgs e)
{
MessageBox.Show("Click1");
}
private void textBox2_Click(object sender, EventArgs e)
{
MessageBox.Show("Click2");
}
}
}
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