How to make a clickable, transparent, and borderless form? - c#

I'm trying to place a transparent and borderless child (WinForm) form on top of another child (WinForm) form that is opaque, but I'd like to retain the ability to directly click on the transparent form. There are a few answers on the web regarding making a transparent form that can be clicked through, but I want to make one that I can click on.
I've found this answer, which shows that setting my transparent form's BackColor and TransparencyKey to something specific like Color.Red achieves the desired behavior. However based on this answer, it seems this behavior between certain Colors and TransparencyKey may actually be a long-running bug.
Ideally I don't want to rely on a bug to achieve a desired effect. What would be a more "appropriate" approach for making a clickable, transparent, and borderless (WinForm) form?
Update (Additional Context):
I'm basically creating a screen pixel previewer for color data extraction.
Overlay forms containing captured bitmap(s) of the screen area.
Another form that gives a visual indicator for the pixel area being previewed (small black box in the below snapshot). This form is placed above the bitmap forms. I have this form as transparent (to see through to the below bitmaps), but I still want to be able to click on it for event processing.
Without the TransparencyKey = BackColor = Color.Red trick, clicking within the small black box causes focus to move to the below bitmap form, which then covers up the small box form and the preview window showing the zoomed view. The purpose of the click is to capture the cursor position for additional processing. I can work around this by immediately giving focus back to the small box + preview forms, but that occasionally causes flicker.

Related

C# transparent form causes image to have ugly borders

I have a transparent form in C# and on top of the form I have a splashscreen picturebox with an image. The form's backcolor is actually just Control gray. I also just set the form's transparencykey to Control gray as well. I used the tutorial here to make the form transparent: How to design a cool semi transparent splash screen?
The image is stretched over the picturebox to make it fit nicely on all computer screen resolution. Here is the original image, notice that it has a transparent left side with squares which does not have any borders.
OriginalImageInPhotoshop
However afterwards, the form has these ugly borders on the left side of the image that are the same color as the backcolor & transparencykey (in this case, Control gray). If I place the form over a black background, you can quite visibly see this. How can I get rid of this?
Problem
So far, only remedies I have found is to either not have the image set to stretch in the picturebox (but that would cause it to appear different on every computer screen!) or perhaps theres another way to make a form transparent...

WinForm Controls are transparent, and not displaying properly

When a form loads, I'd like it to show a loading image (within a Picture Box) and a standard Windows label with some text. However, all I see are white boxes, or sometimes I see another form underneath. How do I get the image and label to display properly.
I've tried setting AllowTransparency to false when the form loads, and also setting the Transparency Key of the form to some other colour, but nothing has worked.
The project is C# .Net v3.5 (also tried v4 and v4.5).
Any ideas?
First, you can't display an image, busy-wait, and then change the image - this will never redraw anything, leading to the symptoms you describe. To "wait" you will need to return control to your main application loop so it can continue to process messages (e.g. to handle redraw requests for your window). One way to do what you want is to display your initial state (splash screen) and then use a timer to call you back later to change the display to your second state.
The next problem you face is using forms controls with transparency. Most controls treat "transparent" as "fill your background with your parent controls color", which is not what you want. An easy way around this is to implement a Paint handler and draw the image and text for yourself - this gives you much more control of how your display looks, and will also allow you to get a cleaner redraw (no flicker or other problems caused by the display being built up but by bit in several controls)
Lastly, consider implementing your splash screen display as a separate control/form that you show above your main form during loading, as that makes it easy to "overlay" on your main form without having to change its design at all.
Just write formObjectName.Refresh() after formObjectName.Show()

Animation Effects in WinForms/C#

I'm pasting an image from the game im building.
the matrix of empty cells you see are made of PictureBox[][].
I wan't whenever I drop a coin to one of the columns... I want it to go down but the purple stuff will hide the falling coin and the gray color you see wont hide it.
How do I make this effect?
please notice that in each PictureBox control I have set the BG Image as you can see
Don't do it like that.
Create custom control. In custom control, override Paint, and then draw COIN sprite first, then draw mask over it. Be sure that you use double-buffered painting here.
It will work like a charm, trust me!
And, since you are (I gueess) building 5-in-a-row game here, your custom control will be able to paint occupied slots as well.
By designing custom control, you'll be able to hide all the animation and graphics stuff away from your main form.
I don't think it is possible like that. Controls in WinForms cannot be transparent, that is the problem
I would think in three directions:
Forgetting about controls and
painting everything OnPaint event of
the form. It is not too complicated
(well it would be more complicated
to detect some mouse events like you
did now, as you wouldn't know which
graybox is hit, but rather just
mouse coordinates)
Experimenting with coin as a form
(forms can be transparent)
Possibly using WPF with same logic
you did, as controls can be
transparent there
Controls in Windows Forms can be transparent. You need to set the TransparencyKey of the Form to some color that you never plan on using (many people seem to love/hate Magenta for this), and then set the BackgroundColor of each PictureBox to the same color. The result should be a transparent PictureBox with its Image drawn over it. I'm pretty sure this won't work with the BackgroundImage property, mind you- just the Image property.
One potentially unwanted side effect of this method is that you'll be able to see whatever's behind your form (the desktop, other application windows, etc.) through the transparent places in the PictureBox.

How do I scrape what a transparent panel shows into a bitmap?

Question:
How do I scrape what a transparent panel shows into a bitmap?
Background:
I need to make a form that sits on top of everything and blurs part of the screen but doesn't stop the user from interacting with it. Odd... I know.
I created a form and added a panel to it. I then set the set background color of the panel to red. Then set the form's TransparentKey property to red and topmost = True.
So now I have a transparent panel. Cool. I can interact with the app below it. Cool. Now I just need to add the blur. I would like to take what is showing on panel1 and blur it then display on panel2 that sits over the top of panel1. Or at least that is the idea.
Important detail:
DrawToBitmap() just shows the red background.
This is running on XP.
Yes, DrawToBitmap(). But not on the transparent panel, on the one that's underneath it. If that 'panel' isn't actually yours then you have to use Graphics.CopyFromScreen().
Not sure what you intend to do with it, but drawing the blurred image in the transparent panel will make it non-transparent and you cannot interact with the underlying window anymore. Also, don't use Red, you'll get unintended transparency if the underlying window contains any red. Color.Fuchsia is a good choice, it is a fuchsed-up color.

Form looks like a balloon

I am just trying to create a form control in winform in .net with custom shaped of balloon shape.
There is need of a balloon tooltip which is transparent and I can put buttons on tooltip,but
tooltip in .net does not provide facality that we can put the buttons on tooltip control so
I want to make a form control looks like a balloon tooltip and so I can put buttons on that form looking like a tooltip.But I cannot show window form control look like a balloon tooltip.
So what should I do??
I tried in one way that I create a image in powerpoint of balloon shape and set it to as background image of form property.But there is no solution with that.
The Control class supports a BackColor with an alpha < 255, it is automatic. It asks the Parent to draw itself to produce the background of the control, then draws itself on top of that. However, you'll want a top-level window for a balloon. That's a window type that can arbitrarily overlap another window and isn't confined by the client area of an underlying window. It has no Parent. A ToolTip is such a window.
The only control available in Windows Forms that can be an top-level window is a Form. Problem is: the transparency trick no longer works. Since a top-level window doesn't have a Parent, there isn't any obvious window to ask to draw the background. It could be many windows, belonging to other processes. You can get transparency in a Form with its TransparencyKey property. But that's a "hard" transparency, equivalent to an alpha of 0. You probably want a soft one. Another nasty problem is that drawing anti-aliased (ClearType) text no longer works since there is no reliable background pixel color anymore.
Long story short: you can't make this work well unless you confine the balloon to the client area of a form. A control, not a form.
You can try to hook on the Paint event of the control and draw the Visual of the button there.

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