C＃点击控件

Question

I'm trying to create a custom control which fires an even on click. My control is just a panel with a couple of labels and a picturebox inside.

The click works perfectly, the only issue is that I have to click the background of the control and if I press on the picturebox, is not working.

I've added the on click event to the control, but I would like to press in every place of it to trigger the event, not just the background of the panel.

I thought about adding a transparent object that covers entirely the control. I actually don't like this idea, however, I've tried with a picturebox, but i cannot see through it. It's not transparent. I can just see the panel background but It covers the labels and the image.

Thanks for the support.

Answer 1

If you just have a couple of objects in your panel, you can hook the Click event of all objects it contains to the same event handler, there is nothing wrong doing this.

public class MyUserControl : UserControl
{
    public event Action<MyUserControl> MyControlClick

    public string ID {get; set;}

    public MyUserControl()
    {
        InitializeComponents();

        // The same event handler code will be used for the three controls
        myPictureBox.Click += global_Click;
        myLabel1.Click += global_Click;
        myLabel2.Click += global_Click;
        this.Click += global_Click;
    }

    void global_Click(object sender, EventArgs e)
    {
        if (MyControlClick != null)
            MyControlClick(this);
    }
}

If you have a more important amount of objects, you can rely on this answer to create a truly transparent panel that handles clicks. The drawback is that you will have to detect which object has been clicked by using HitTest based on the mouse location.

On the form side :

aControl.MyControlClick += aControl_MyControlClick;

// ...

// This code is triggered when a MyUserControl is clicked
void aControl_MyControlClick(MyUserControl ctl)
{
    MessageBox.Show(ctl.ID);
}

Answer 2

Actually! You cannot raise any event to the element in the Usercontrol unless you have to apply own method to your usercontrol or you can disable the element in the usercontrol but it will change the color of that element but It will raise the click event when you click your control.