I have a form that contains a lot of runtime generated controls (image, button, panel,...), about 100 controls (I'm making a card matching game so there is a lot of controls in the form).
I place the generating code into the constructor and each time the app starts, it took about 3-5s to load all the controls completely.
If I bring another window on top and then back to my app, the controls will be redrawn again.
How can I prevent the controls from being redrawn? If you don't mind, please give me a simple example in C#.
Any help is appreciated!
I found this article that explains how to do this in .NET by calling the WIN API SET_MESSAGE function to set the WM_SETREDRAW flag for the control you do not want updated. Although you can stop certain controls from updating, are you sure you can't approach this issue by reducing the number of controls on the page? 100 Controls seems like a lot and may be an indication that you need to have multiple views.
Enjoy!
My suggestion is to use the form as a drawing surface and draw your card bitmaps directly onto the form. Its not hard to do.
You can add a handler to the form Paint event which will give you parameters with a Graphics object. Use graphics.DrawImageUnscaled to draw each card at the location you want.
This will make the app much much faster.
Preventing a control from redrawing is fairly pointless. You'll get a hole where a control was supposed to appear, your user won't have any use for that hole.
It redraws slowly simply because you have too many controls. You can only get it to redraw faster by using less controls. Or by using controls that can display multiple items in one window, like ListBox, ListView, TreeView, DataGridView.
Note that your specific issue is fixed in Vista and Windows 7. The Aero theme uses off-screen buffering for windows. Which means that windows don't need to repaint themselves anymore when they are obscured by another window. You will however still get slow redraws when the user minimizes the window and restores it.
You might want to consider using a single data table control. A ListView (or something like ObjectListView) may be a good option.
If your data isn't really a list/table, you should split the controls into separate tab pages, which would improve both performance and usability.
Related
I'm making C# application design with images, but when I launch it, I see loading images (~1sec), so how to make simple loader, when images (background, logo, etc..) fully loads, to show my app? I know it's possible but I don't know how to. Thanks so much!
This sounds like standard behaviour. The controls get painted one by one in z-order and if one is slow the rest may appear to flicker.
You could try double buffering the whole form as shown here:
How to fix the flickering in User controls
Alternatively you could suspend the layout while everything is drawn and resume it afterwards:
How do I suspend painting for a control and its children?
I've set my XNA game's DeviceWindowHandle to a PictureBox with Dock set to Fill on a Form, effectively providing the powerful array of .NET controls to my game. I'm aware this comes with a handful of niggly things to clean up, one of which is my problem explained below.
I'm trying to figure out if it's possible to avoid the WM pump pausing when doing things like clicking to drag a ScrollBar control, or right clicking in a TextBox control, this ultimately causes my renderSurface (the dock filled pictureBox) to stop being drawn to temporarily. Information on this seems sparse, though it's likely i'm not looking in the right places.
I could tie in some custom drawn XNA ScrollBars and set ShortcutsEnabled on the .NET TextBox's to false, but i would rather fix the root of this problem if possible.
Thanks in advance.
XNA works by having a game loop. WinForms and native c++ Windows GUI apps work by having a message pump. Sounds like you have fused the two somehow.
Perhaps you need to call the base Game.Update() somehow from within your forms's Control.WndProc
I used this code from the code project in order to display a .png image (with transparency). At line 87 I tried to add a label in which I succeeded but somehow It won't appear on the form. I tried Refresh, Invalidate but none of them worked. Maybe someone can point me into the right direction.
I think, since you're using UpdateLayeredWindow the "normal" painting mechanism is disabled, i.e. no WM_PAINT messages are sent to the window, and the WinForms library has no chance to render the Label Controls.
I found this article about using layered windows on MSDN stating:
Note that when using UpdateLayeredWindow the application doesn't need to respond to WM_PAINT or other painting messages, because it has already provided the visual representation for the window and the system will take care of storing that image, composing it, and rendering it on the screen. UpdateLayeredWindow is quite powerful, but it often requires modifying the way an existing Win32 application draws.
So I'm afraid that WinForms isn't able to work together with your approach. Even if it would, you would likely get unpleasant results since "real" transparency is not easily done with winforms (i.e. the labels wouldn't show up transparently but would be drawn the parent forms background color)
I am trying to create a panel which will have a set of "buttons" on it.
These buttons should have the following behaviour:
Appear similar to a tag (with
rounded edges)
Contain a red
cross to remove the filter/tag from
the panel, similar to the way internet
explorer tabs have an embedded cross to close the individual tab.
allow the user to click
on the tag and respond like a normal
button (as long as the click is not
in the red cross)
Number 1 is no problem, this is just appearance, however, regarding numbers 2 and 3, I am not sure if there is already code out there do to something similar...and I dont really want to reinvent the wheel if I can avoid it!
My question is: Does anyone know if there is something out there in infragistics which will do this simply, or will I need to write this myself by subclassing winform buttons?
Thanks in advance!
Is this new development or maintenance of an existing project?
If it is maintenance, you have a somewhat tougher time ahead. You'll implement a UserControl, probably segmented into two buttons. Use docking to get the behavior as correct as possible. The far right button would contain your cross image; the left (which would need to auto-expand as you resize the control) would contain your primary button behavior. Play with the visual styles until you get them right (EG, removing borders, etc).
If this is new development, and you haven't gotten too far into it, you might consider using Windows Presentation Framework (WPF) instead of WinForms. It will be easier to build the control and get it to look exactly how you want it. WPF includes an extremely powerful control compositing system which allows you to layer multiple controls on top of each other and have them work exactly as you'd expect, and it carries the added advantage of allowing full visual control out-of-the-box.
Either way, this is more work than dropping in an external component ... I've used Infragistics for years, and I can't think of anything they have which is comparable. The closest, but only if you're building an MDI application and these controls are for window navigation, is the Tabbed MDI window management tools -- and there, only the tabs (which replace window title bars) have this behavior.
I don't think that infragistics can do something like this. The UltraButton control can't.
Implementing a own control wouldn't be that hard.
your probably going to have to make a costume control for this type of work.
i have a winforms application. i have a user control with a lot of icons. the user can load this control on a form many times (in a tabbed layout). right now i am loading the icons each time the control is created (could be up to 50 times in teh app). is there any way to cache these icons in the application. if i did this, would that decrease the number of gdi handles that i am using as this is becoming an issue.
You can make a singleton class for each icon. The first reference it creates the handle. Subsequent calls uses the existing handle.
Without knowing more about your user control my next suggestion can be only be very general. But you could have a single bitmap layer on which you draw all your icons. The remaining elements of your user control would exists above and around this bitmap.
Unfortunately this idea may be problematic performance wise. Require you to refactor the code you all ready use for arranging icons. Finally it is non-institutive from how frameworks with a control-form structure ideally works.
We ran into a resource problem with entry forms for the parameteric shape we ship with our CAM software. Too many text entries caused various forms of strangeness and leaks. So we instead created labels with borders that looked like text entries and had ONE text entry (and a combo box entry too). When the user tabs, enters, or clicked the single text entry moved to the new entry and the label was setup for the previous entry.
This is totally a non-intuitive setup than how you would normally code this but it was the only way to deal with our resource problem.
In my experience it seems that GUI Frameworks have issues when you have to deal with dozens or hundreds of entries and that you have to approach the problem using a different design.
If the issue is the number of "icons" (not sure what you mean here) you can use Image-Lists. For example, a Listview control can reference icons in an image-list, instead of keeping a full copy for each item (not sure if this applies to your case though).