Develop Reference

c# anchored controls "shakes" while resizing

I have a control on my app that can be resized by the user, it has some button anchored to the top-right side and also a scrollbar.
The problem is that when the control is resized, the controls anchored to the right also changes the position, and only after a few ms the controls goes into the right place. So it looks like the child controls "shakes" while the parent control is resized.
I already tried all kind of things, like using SuspendLayout and ResumeLayout on the parent control, setting double buffering and other styles on each control to true, setting WS_EX_COMPOSITED bit, but nothing seems to make this issue go away.
This issue is present on other apps too, and is pretty annoying.
So is there anyway to fix that on .net?
Maybe making it render everything to a backbuffer, and then when everything is finished render it to screen?

I would create a new event that fires after resize is done, using a little timer magic stopping and starting a timer with an interval about 50ish ms on each resize event you can create this fake ResizeEnd kind of event.
On the first resize event I would stop the drawing of the UI using the dllimport call (dont recall which it was) to stop drawing the contents of your window or control. Then when the resize is done, enable drawing again using the same dllimport call.
The effect would be that it will only redraw itself after resize is done or every 50ms if you pause while resizing.
ResizeEnd: WinForms - action after resize event
SuspendDrawing: How do I suspend painting for a control and its children?

override the below virtual method from namespace using System.Drawing;
protected override Point ScrollToControl(Control activeControl)
{
return AutoScrollPosition;
}
should solve the problem !

Strange white area in panel c#

I have a problem with panel and weird area on it. I fill my panel with many PictureBoxes 32x32px, and a small area of this panel is filled with white area.
Here is how it looks like:
You can see that the first PictureBox has specified grass image, which is 32x32px, but the PictureBox below has only half of it's image. It's very strange.
I have also an onClick event specified for PictureBoxes to change it's background to other image. If I click on 'working' PictureBox it's background changes, but when I click on 'corrupted' one, it doesn't.
So basically, my question is - what could be the reason for such effect? Is it possible to find it out without analysing a code? I would like to avoid putting a code here, because it's very complicated and long.
EDIT
I used WinSpy++ and it is the result (red point is a place where i hover cursor)
so we can see that PictureBox is partly hidden behind this white area.

I don't know if the question is still active, but I'll try to respond anyway. It is more a comment on it, but since I'm not allowed to make comments yet I'll just answer.
I had encountered a similar issue when implementing some picutreBox drawing using onPaint event handler. The problem was that I called pictureBox.Invalidate() during onPaint and it caused displaying of the unwanted white color box. You might want to avoid using Invalidate() or Refresh() in your onPaint event if there is one.
If this is not the case it might also help to refresh the form or pictureBoxes that are corrupted. Try to call this.Refresh() after the form initialization, preferably in onLoad or onShown event handler.
If it still doesn't help then the problem is somewhere else, I'd guess there is a control hidden somewhere that causes that. But we'll need to see some code in order to suggest any other advice.

Balloon pop up over control mouse enter/exit

Hello,
Above is the program I am writing. On the right panel is basically two custom controls (the blue rectangle area) I created and just added them as controls to the background panel control when this winform program loads.
I used MS paint to draw out the pop up balloon that I want to see when my mouse enter this control's area. I want to do the following:
1. If mouse enter the control area, the yellow area balloon pop up and populate with the information of that specific control
2. If mouse move out of the control area, the pop up balloon disappear.
Can this be done with Winform application? I looked around and found out about Tooltip class but so far from researching I don't know if it does what I want to do.
I could be wrong but googling around gave me the impress that Tooltip offers very little in term of style. Ideally I want to make this pop up balloon into almost like a border-less pop up window where I can put image , font ect.....at will. Also Tooltip works if you hover over a button or specific field whereas I want the entire control area.
Can this be done? I appreciate if you can point me to any work around if there is one.

I wrote a comment, but I figure I'll expand it into a full answer. This is assuming you want a new control, which isn't a tooltip, for maximum customizability. I did something similar to this for work recently, to act as a non-modal info popup that disappears when clicked.
Creating a Custom Popup Form
What you want is essentially a floating popup that appears over your form, which means you'll want to define a new Form object, rather than a UserControl, as it won't actually be embedded within your other form.
Give it a multiline, non-editable textbox that you can fill with the information you want to populate, then simply call a new instance of the form on your Mouse_Enter event. Close it upon Mouse_Leave.
Adjusting The Style
You'll have to play with it a bit to get it to actually act like a popup and not just a window. I'd recommend setting it to a non-modal popup, and removing the border. You can write a function to automatically size it to its contents. I don't imagine you'll want the user manually resizing it.
Some other things to look into would be overriding the CreateParams property that comes with the basic Form object. You can force DropShadows and TopMost forms without making the form modal. Overriding ShowWithoutActivation to always return true will prevent the form from stealing focus when it pops up.
I'm not sure if you can pull off rounded edges like you have in your mockup. Perhaps you can pull it off with some wizardry in the OnPaint() function, but I couldn't tell you how to do it.
It might be a bit of a pain for fiddling around with, but you can get some good functionality and appearance out of it. If you think you can pull it off acceptably with the ToolTip class, go for it. It took me about a week to get my notifications where I wanted them (though I added several features that you probably don't need to worry about).
Examples
Some keywords to look up in related searches would be Toast Notification and Non-Modal Popup. This might be some use:
http://www.codeproject.com/Articles/442983/Android-Style-Toast-Notification-for-NET

Since you already have implemented custom user controls you might want to try it again. Make a control that is that style and color, changes it's size based on it's text. You can feed it information (such as the text to display) from your existing user control object. You can also have the mouse enter/leave code reside in your first user control.
If you're not sure how to make a rectangle with round corners you can either make it on the fly using a graphics object (which will turn into a bitmap on the screen) or make it how you want it to look in GIMP (or photoshop if you have it) then use that image as the background on your user control. Make the default background transparent (so your voids above the round corners are not grey). If you make a pre loaded image you'll need to be aware you will only be able to scale it equally in Y and X directions. unequal scaling will make it look distorted.

Can you use the Mouse_Enter event on the control?

Custom control under modaldialog not repainting when moving dialog

What causes this ? Other controls are shown fine ...
public CustomControl()
{
SetStyle(ControlStyles.ResizeRedraw, true);
SetStyle(ControlStyles.OptimizedDoubleBuffer, true);
SetStyle(ControlStyles.UserPaint, true);
}
The customcontrol is placed in a TableLayoutPanel.
...................
Edit: For clarification:
Suppose you have a window-sized control with a small modal dialog form on top. When you move the dialog window, it's like your painting with the window on the control (the borders are painted on the control). The control doesn't repaint itself like other controls do on the same form, ie montcalendar or other custom controls. I can't seem to find the cause of this ?
Small detail of drawing artifact:

Hard to tell from the snippet. The standard mistake is to draw through Control.CreateGraphics() instead of the OnPaint() method. Won't work, Windows lets the OnPaint method run when parts of the control get uncovered. Which wipes out whatever you drew. Another failure mode is deriving from a control that's a wrapper for a native Window control. UserPaint is not supported for these type of controls, the native Windows code has to do the drawing.
It is clear from the screen shot, note how the text is staggered. That's because the OnPaint() override is using the e.ClipRectangle property to figure out where to draw. That value always changes when you slowly drag a window across your control, it only tells you what part of the control needs to be redrawn. It does not tell you where to draw. That has to be based on the control bounds, routinely the rectangle from (0,0) to (ClientSize.Width, ClientSize.Height).
Only ever use e.ClipRectangle to optimize the drawing. Like skipping an expensive drawing detail when it is outside of the clipping rectangle. It is otherwise a small one, Windows is already quite good at clipping automatically.

UserControl OnPaint always has clipRect of {0,0,0,0}

I have a UserControl with a few buttons on it. I want to override OnPaint and paint some other stuff on the control.
So I override OnPaint.
Whenever OnPaint gets called the ClipRectangle is always {0,0,0,0} and so nothing I do gets drawn on the control.
What am I doing wrong?

Ok, Ive sussed it now. Its a bit silly. I had a TableLayoutPanel that was docked to the control. That seems to clip out all the areas that we can paint on.
I created a new control that derives from TableLayoutPanel and used this control instead. Its OnPaint gets the full clip rect.
However, that wasnt any use anyway... It seems I have misunderstood how Windows painting works. I thought I would be able to paint directly over the top of my controls, but this isnt the case. The controls get placed on top of my painting.
Gonna have to mess about with panels to get this working I reckon..