How to make a object transparent in windows forms app

Question

I have a simple use case. I have a preview window on which I am displaying a usb webcam. Now this preview window is not clickable ie does not detect on click event. As result I want to put a transparent object on top of this preview window. So that I can add on click event to it. Is there a way to make any object truly transparent so that it display whatever is going on behind it ?

Answer 1

I had a similar problem to this. Solved my problem but might not yours.

I used: Timer interval was 30ms. Picture Box Camera Feed.

I had a timer and on every tick i set it to capture the image from the webcam feed and sent it to a picture box and set the captured image to the picturebox.Image. The picture box filled the view to act as a preview window.

I had click event on the picture box which then let me click on the view and then proceed.

Answer 2

You can hook into your LiveDeviceSource to catch the messages sent to it using this technique:

public class Form1 : Form { 
   public Form1(){
      InitializeComponent();
      proc = new LiveDeviceSourceProc();
      Load += (s,e) => {            
         proc.AssignHandle(yourLiveDeviceSource.Handle);
      }; 
      proc.Click += (s,e) => {
         //you can also process your code here
      };
   }
   LiveDeviceSourceProc proc;
   public class LiveDeviceSourceProc : NativeWindow {
     protected override void WndProc(ref Message m){
        if(m.Msg == 0x202)//WM_LBUTTONUP   <=> Left Mouse Click
        {
            //process your code here
            if(Click != null) Click(this,EventArgs.Empty);
        }
        base.WndProc(ref m);
     }
     public event EventHandler Click;
   }
}

Answer 3

First of all, in your form, you have Enabled property, and you can do:

this.Enabled = false;

to make the entire form disabled.

Second, but not recommended, you can create your own transparent control - read about it here .