I've tried to find a way to change the layout of the background image on the ListView control.
I've searched around but haven't got any straight answer.
I can see that there is a ListView property BackgroundImageLayout which is supposed to do the job. But when i change it nothing really happens beside that the BackgroundImageLayoutChanged event is triggered.
How it is possible to change the BackgroundImageLayout on the ListView control? Is there any possible workaround to achive my goal?
PS.: I know about 3rd party controls that 'fix' this problem, but I'm looking for a solution that would do the task without any additional components.
ListView is a native Windows control. Yes, it does support a background image, the LVM_SETBKIMAGE message takes care of it. It however doesn't support the boilerplate Winforms BackgroundImage support, notable lacking is BackgroundImageLayout, the property that Winforms implements for the Control class and implements when the ControlStyles.UserPaint is turned on. It is not for native Windows controls, they paint themselves.
The guy that wrote the Winforms wrapper class for ListView did the next best thing, he added a new property to the ListView class called BackgroundImageTile. A layout option that the native Windows control does implement. Which leaves you with just the two layout options that the native control supports. Tile or don't tile.
That same guy did some pretty heroic things to make the Winforms wrapper class behave reasonably. The code is filled with hacks to work around the native control's quirks. Awesome work. His life would have been a lot easier if the Windows team guy would have the luxury to make the Winforms guy's life easier. But it doesn't work that way, ListView has been around a lot longer than Winforms. And wasn't designed that well from the getgo, Microsoft had pretty significant growing pains around that time.
Fast forward and change the rules so you don't depend on legacy code: WPF, Silverlight, WinRT.
According to the MSDN, 'ListView.BackgroundImageLayout Property':
"The API supports the .NET Framework infrastructure and is not
intended to be used directly from your code."
and
This property has no effect on the layout of the background image of the ListView control, therefore it is not shown in the designer or by IntelliSense.
Use the BackgroundImage property to set the background image. See msdn for more info:
That is unless you have something fancy you are trying to do with it?
EDIT: As per a previous thread HERE: the short answer is that you can't. =(
If you desparately want it, try creating a blank image that is the dimensions of your ListView. Add to this image YOUR image and add at it a position that is in the middle. There may be something similar in nature to this in under Bitmaps or Images.
Related
I have noticed that some WPF controls have some decent effects available to them (drop shadow, reflection etc), and was wondering if it was possible to use these WPF controls solely for their available effects?
For example, I have an image manipulation library that resizes and letterboxes disparate sized images but I would like to add drop shadow effects to the resulting images. The WPF image control has this effect available, but how easy is it to use in an environment where there will never be a GUI (console app or ASP.Net library/handler for example).
Thoughts?
Cheers
Moo
You can use them, yes. The only problem is that you have to use them within STA threads, which you probably can't count on happening automagically (e.g., response threads in ASP.NET are MTA).
I'm using WPF controls in a windows service app. I just have to transition to an STA thread before I do my rendering.
Take a look at RenderTargetBitmap. You could do whatever with your WPF component, then render it as a bitmap, and then use that bitmap on your ASP page.
I'm not sure that is the best way of doing it though. Is Silverlight out of question for you?
I have hosted the VLC.DotNet windows Control in a WindowsFormsHost element, inside a WPF window. The reason behind doing this, instead of using Vlc.DotNet WPF control is because the performance of the WinForms version is twice better than the WPF version.
Anyway, everything works fine, except for one annoying detail; When using the WinForms version inside a WinForms App, the rendered video will exactly fit the control; However, using the same control inside a WindowsFormsHost element, causes the video to be rendered as it's original size and not fitted to the control.
There are 2 things to notice here :
The WinForms control is exactly the same, so in my opinion, this behavior could not be related to it.
Using Spy++ I've managed to see when the control is used inside a WinForms App, the rectangle of the rendered video is exactly the same size as the rectangle of the Control itself, But when used in WPF App, the recatngle of the video (which is rendered by VLC and I have no control on it) is not the same size as the control. Instead, it has the same size as the video itself.
Anyone has any particular ideas on why WPF is showing this strange behavior?
Any suggestions would be appreciated.
Thanks a lot folks.
Finally, I managed to find out what was causing the problem and resolved it!
I should confess that the problem was not even remotely related to the first 2000 things that comes to mind in these situations! Instead, it was related to the most ridiculous thing that never happened to catch my eye! Well, as they say, it's always in the last place you look!
As weird as it may sound, the problem was related to video scaling! I needed to scale the video and apparently, when you set scaling in vlc, the video wont get fitted to container anymore.
That was it!
I need to write a complete diffrent looking textbox than the original winforms textbox. In fact I need a different background, how can I achieve this? I tried owner drawing with SetStyle(ControlStyles.UserPaint, true); but this caused a lot of flickers and the text was completly wrong drawn, wrong font, size etc.
Wrtiting a textbox from scratch would be overkill, I think.
This is not possible. The TextBox class is a wrapper around a native Windows control that has been around since Windows version 2. It had to run on some seriously sucky hardware, they had to break a few rules to make this work. One of which is that it draws parts of itself without using the standard Windows paint cycle. Invalidate() and OnPaint() in Winforms terms. Fixing this behavior wasn't possible due to app-compat problems. Way too much code out there that hacked the control in creative but unpredictable ways.
Accordingly, it isn't possible to intercept the drawing to prevent it from erasing parts of your background image. There is no workaround for this, creating your own is a lot of work. Consider WPF.
If you specifically need a different background on a text box, one work-around is offered here.
Such a decent question,how do I add images(I googled,but they say I have to add approximately 50 lines of code to do that,why?)?
A big problem with WinForms is that it is just a small abstraction over the native windows UI controls. As long as WinForms supports the required functionality, such as the icons on ListView as Tim mentioned, it is relatively easy to accomplish the task but as soon as WinForms does not support the functionality you want, you need to implement it almost from scratch. Luckily List controls in WinForms provide a relatively easy way to draw your own content using the owner drawing functionality.
Easier way is to have a look at WPF which is much more versatile framework when it comes to requiring more specialized functionality. Though this requires .Net framework 3.0 or greater and has a bit steeper learning curve.
It depends where on the item you want the image to appear.
To set an icon to the left of each item, first set the control's LargeImageList and/or SmallImageList properties, then set the item's ImageIndex property.
To display an image anywhere else on an item, you'll need to use the list view control's owner drawing functionality. There's an example in MSDN, although this may be the same 50 lines of code you've already found.
I was just wondering if there are ways of creating my own custom winforms controls?
I've been plundering with Visual Studio 2008 now trying to do some c# apps. And the GUI end up looking terrible because of the standard winforms limitations.
And I noticed that I can add images to buttons for example, but ther's no hover effect. Or, the hover effect makes the whole button area gray. I don't want any of that, I just want to either create my own graphics for the controls or find some free (opensource perhaps) controls that already exist.
Any light on any of this, anyone? :)
You can write complete Winforms controls from scratch, doing all the painting and input processing yourself - you just create a class derived from 'Control' and get on with it.
There's a fair bit to making a first-class control which integrates nicely with the VS designer, so people tend to derive their custom control from an existing control which has most of the behaviour they want.
Here would be a good place to start: http://msdn.microsoft.com/en-us/library/6hws6h2t.aspx
I'm puzzled, you are doing WinForms development, yet in comments say you have done many months of WPF development, but WPF is not good enough because it is not cross platform.
How is WinForm more cross platform, and have you seen how ugly WinForms looks under mono on a Mac as it's draw via X11.
If you want style and cross platform, go for Flex or Silverlight, as your already know WPF I'd go the Silverlight route.
It's cross platform, and has all the beauty of WPF, but at the cost of reduced functionality out of the box.
First - may be more pragmatic to look at WPF, or hosting some WPF elements inside winforms (which is supported - like so). Other than that - you can do all your own painting if you want; but it is a lot of work.
Any reason why you don't use WPF? You have much more more UI control if you went down the route.
If you must go with WinForms then there are many commercial solutions like DevExpress. If you really want you own look and feel it'll be alot of work.
Yes. You can create your own controls. It is called a User Control. Just select Add->and User Control.
WPF is a good alternative if you want your windows form to look fancy.