WPF 15 extra pixels in Window display - wpf

I come from a WinForms background, so WPF is foreign to me. I am experimenting with it and trying to make a simple Hello World! application, except that the application displays different at runtime than how it is in the designer.
What I mean by that is I have a 'Hello!', and in the designer the location of the button is 12, 12, and and the Window is sized so that is the right/bottom edge of the button is 12, 12 pixels from the right/bottom edges of the window (so there is uniform 12 pixels around the button). When I run the application the button is still 12, 12 pixels from the top & left edges, but is 27, 27 pixels from the right/bottom edges of the Window. I have verified that the button dimensions are correct (I took a screenshot and measured the button in Adobe Photoshop and verified that the button width & height in the XAML code was the same as what was displaying on the screen). The Window is what is growing bigger.
I also verified it was not the canvas getting bigger by explicitly setting the width & height, changing the background color, and setting horizontal/vertical alignment to left/top. So when I ran it again, the canvas stayed the same size, but the Window still had an extra 15 pixels on the right/bottom.
I have tried Googling & searching here for this problem, but can't find an explanation as to why runtime is different from the designer.
I should note I am using Visual 2010, and I am using a simple for the layout.
Anyway, thanks for any clues as to why I am getting 15 extra pixels.
(Note I'd post a screenshot, but as a new user I'm not allowed).

You can use a tool like Snoop to diagnose this. It should allow you to inspect the entire visual tree of your application, and determine which UIElement is responsible for the extra pixels.

Related

PrintScreen contents are larger than what I see

I would happily provide a screenshot of this, however the problem is the captured image, is much larger than my actual desktop.
I am completely frustrated with this as I have tried using BitBlt with the desktop hdc AND the new "Graphics" commands.
My actual desktop resolution is 1920x1080 - 1080p .
BitBlt and "Graphics" both return that my resolution is 1536x864 # 96 DPI.
A form (WinForm), Maximized, borderless, and irrelevant of scaling mode the form is set to, also shows 1536x864 # 96 DPI.
Now the image that is captured, is like it is being done from 1920x1080, but clipping the region 1536x864 as the screenshot.
If I do PrintScreen directly using Prtscn button, I get the entire image, but still it is about 1.5-2x larger than what I actually see.
What I am looking for -- is a resolution for how I can take a picture of what is on my screen in the scale/dpi/whatever is going on here that it visually looks like. I have written a screen capture program, and using a few different examples for the RubberBand form (overlay form to select a region of the screen by drawing a box), and as you can imagine, this scaling crap is causing those box captures to be offset, and the contents are zoomed.
This is very annoying -- even to explain, however I am positive that most of you are familiar with the terms I use, and also know what to expect from taking a screenshot, so my explanation above should be pretty clear as to what my problem is.
Example/Consideration
Imagine, taking a picture of a window that is 300x300, and getting the top left 150x150 of that zoomed to 300x300 completely skipping the remainder of the window. Resulting image is still 300x300, but it's not what you selected.
Now imagine, you grab a picture of your screen by the only dimensions you can get programmatically, and then put the image into a picturebox. Even though both your screen and the picturebox claim to be the same dimensions and dpi, the image in the picturebox requires scrolling even if the picturebox is maximized to fullscreen on a borderless with no borders / etc. -- again, the picture is zoomed, but how is it still reporting that it's the same size as the form XD (comparing Graphics or BitBlt dimensions with the actual form. also tried comparing picturebox contents, and still same effect)
This, is EXACTLY what the effect is that is happening. When I try to capture a region or segment of the screen. I am not sure why windows api/crl is lying about this seemingly trivial stuff, however there must be a way to accurately obtain screenshots/capture regions without this faux zoom effect -- across all resolutions.
Thank you Hans Passant for pointing me in the right direction.
To add "true" dpi scaling support to a winforms application, you can make it so by adding the following block to your manifest :
Project > Add New Item > Visual C# Items > Application Manifest File
One the file has been added, open it up and look for a line like
</asmv1:assembly>
Whatever the "asmv" number is, (in the example above it is 1), use that to format the code:
<asmv1:application>
<asmv1:windowsSettings xmlns="http://schemas.microsoft.com/SMI/2005/WindowsSettings">
<dpiAware>true</dpiAware>
</asmv1:windowsSettings>
</asmv1:application>
Paste the above code (changing the asmv1 to whatever version the manifest is), just above the final closing line for the ""
Also, make sure your forms are set to AutoScale to dpi (and all sub-elements).

WPF: Anchor points don't work well sometimes

When I try to create a window using WPF (usually when the window is not re-sizable) this problem which has been shown in the below images happens. Although I can easily fix it by shrinking the inner frame a bit, I'm curious why it happens and in case it is a kind of Visual Studio form designer problem, why It's been happening for quite a long time.
Fixing the inner frame according to the designer view anchor points results in:
Don't position your controls absolutely. Remove the Height, Width, HorizontalAlignment and VerticalAlignment from your Border so that it takes the entire window. Then set your margin to an uniform one (Margin="10"). It will look perfect for all window sizes.
If you don't want to edit the XAML file manually, you can clear the properties in the designer by clicking on the small square named "Default" near every property.

How to scale form with font size in WPF?

How can i scale a Form with font in WPF?
i.e. What is the WPF equivalent of
this.Font = SystemFonts.IconTitleFont;
In WinForms, if you're a good developer, you honor the user's font preferences. A WinForm that starts out as:
You then apply the user's font preferences:
this.Font = new Font("Segoe Print", 11, GraphicsUnit.Point);
and elements on the form scale to accommodate the new size:
Notice:
the form is wider and taller
the label is positioned further down, and to the right
the label is wider and taller
the text of the label is not cut off on the right or on the bottom edge
the button is wider and taller
but button is positioned further down, and to the right
Note: In WinForms you can also use the line:
this.Font = SystemFonts.IconTitleFont;
WPF doesn't support Font, which is why i provided the clearer alternative. For the example below.
A similar WPF form starts out as:
You then apply the user's font preferences with:
this.FontFamily = new FontFamily("Segoe Print");
this.FontSize = 14.666; //11pt = 14.66
and elements on the form don't scale to accommodate the new size:
Notice:
the label's position has not changed
the button's position has not changed
the form is not wider or taller (text is cut off)
the label is not any wider (text is cut off on the right)
the label is not any taller (cutting off text along the bottom edge)
the button is not any wider (text is cut off)
Here is another example of two buttons that are the same size:
WinForms:
Windows Presentation Foundation:
Bonus Reading
WPF: How to specify units in Dialog Units?
How to prevent WPF from scaling with the Windows font size options?
WPF version of .ScaleControl?
WPF doesn't do primitive font-based scaling because it's... well, primitive. You can see it in your own screenshots.
Here's your "WinForms, before changing font" screenshot. Take a look at how much space there is between "sat on a log." and the right edge of the form.
And here's your "WinForms, after changing font" screenshot. Notice how much less margin you have after "scaling".
If you hadn't left all that extra space, then your label would be cut off with the new font. And with some fonts, it would be cut off even though you did leave all that extra space. That's what I mean when I say WinForms' scaling is "primitive". WinForms picks a single scale to apply to everything, and that scale is not chosen with any awareness of your content; it's based on average statistics for the font, which can and will fall apart once you start talking about specifics.
WPF doesn't hobble you with something that primitive. It gives you an amazingly powerful layout system, where it would be trivial to make a window that scales beautifully. But instead, you're choosing to cripple that layout system by using hard-coded sizes. Stop it.
Hard-coded sizes have two huge problems:
They don't adapt to different fonts. You've noticed this already.
They don't adapt to different content. (What happens when you want to make a German version of your app, and the German text doesn't fit into your hard-coded button size?)
Hard-coded sizes just don't adapt. To anything. You had to use them in WinForms because that's all WinForms supported. But WPF gives you a proper layout system, so you don't have to (and shouldn't) use anything that crude.
All you need is this:
A Window with SizeToContent="WidthAndHeight". That way, the window will be exactly the right size to accommodate the text and button, no matter what font or language you use.
Since you only have two UI elements, and one is above the other, you would put a StackPanel inside your Window.
Inside the StackPanel, you need:
A Label or TextBlock to show your text, with the text in Content (Label) or Text (TextBlock); and
A Button with HorizontalAlignment="Right", and the text in Content.
Set some Margins on the StackPanel, TextBlock, and Button to space things out to your liking.
That's it. Don't set any other properties on anything -- especially not Width or Height.
Now, if you change your font, the window and the button will still be exactly the right size, and won't cut off your text. If you localize your app into a different language, the window and the button will be exactly the right size, and won't cut off your text. Stop fighting WPF, and it will give you great results.
If you later want to make your layout more advanced, you could consider things like:
If you want the button to be a little wider (to have more breathing room before and after the text), try playing with the Padding, or set a MinWidth and MinHeight. (Don't use Width or Height if your button contains text. You might consider using them if your button only contains an image, but maybe not even then.)
If you're worried that the font might make the window so large that it no longer fits on the user's screen, and want to enable word-wrapping, then play around with MaxWidth and TextWrapping.
WPF's layout system is amazingly powerful. Learn it. Don't fight it by using hard-coded layouts and then complaining that your hard-coded layouts suck.

How do I remove the border of a WPF window in the Design view/tab?

I am trying to remove the border of my WPF window in the design view/tab in Visual Studio. Please don't mistake this as a request to create a border less WPF window. I did that and it is working fine. What bothers me is that even if you have set WindowStyle = None, ResizeMode = NoResize, the design view/tab still shows a border around your window in the preview.
Is there a way to remove said border and have a 1:1 preview of the border less window as in Windows Forms?
Every question I have found in regards to this only asks how to remove the border of the actual application. I would like to remove it in the preview.
Any help would be very much appreciated :)
here is a screenshot of my problem:
This cannot be done as this is just how Visual Studio renders a window in design view (I think the frame is probably there so that you can distinguish when you are editing a Window rather than a UserControl).
Rather than try and find a solution to this I would ask myself if this is something I need to be spending time figuring out - after all you say that your program works correctly when being run. I think your time will be better spent writing code for your program rather than trying to play with the design time environment.
Update: In response to you comment, consider that the window frame will be different on every users machine depending on their operating system version (XP vs. Win7) or the theme the user has installed.
My computer has XP installed so the side borders are a lot thinner than those shown in design time so any content will be smaller (but only my a few pixels - 4 in my case; does your user interface design really depend on 4 pixels?).
When using a technology such as WPF you should not be designing your UI to fit to exact pixel sizes; you should be designing with min / max values or using layout containers that adjust to the size of the window as set by the user. Any regions in your UI (E.G. sidebar and main content) should be expressed as a ratio or percentage of one another; instead of saying "The side bar is 150 pixels wide and the main content area is 350 pixels wide" you should be saying "The side bar takes up a third of the window width and the main content takes two thirds".
Although the question is very old and have already been answered (kind of), I just realized: if you set WindowStyle="None", your undesired border is gone.

Button image too far from top of button; too close to bottom of button

I'm working on a Windows Form in VB.NET 2005 and I would like to have some buttons with images (I'm talking about the plain, vanilla System.Windows.Forms.Button). I have everything set up the way I want it but the images are displaying too low on the button, such that the bottom of the icon is almost right on the bottom of the button and there is a lot of space above the image.
Here is a screenshot:
Button Screenshot http://www.freeimagehosting.net/uploads/b28a5c63b8.jpg
See how the corner of the icon is brushing up against the bottom of the button?
My button is 23 pixels high and the image is a 16 x 16 icon (converted to a bitmap so that it can be assigned to the button's Image property).
I've tried setting the button's Margin.All property to 0, and verified that the Padding.All property is 0. I've also tried changing the button's ImageAlign to TopLeft, MiddleLeft, and BottomLeft, but none of those settings seem to have any affect.
Does anyone know how I can position the image to be of equal distance from the top and bottom edges of the button? I can resize the button or the image if necessary but they are at my preferred size and I would like to keep them that way if possible.
I just encountered a similar problem, which I was able to solve by thinking really hard. (Ain't those situations great?)
The explanation
First it's important to understand that ImageAlign does NOT mean where on the button do you want the image. It means what point (pixel) on the image should be used for positioning. So if you pick "TopLeft", then the top-left-most pixel of the image will be vertically CENTERED on the button.
The problem comes in when you have a button with a centered image, whose ImageAlign is set vertically to "center", and whose dimensions are of an even number of pixels. Your image is 16x16 pixels- 16 is an even number. The middle pixel would theoretically be somewhere between pixel 8 and pixel 9. Since there is no pixel 8.5, VB rounds down to 8, thereby using pixel 8 as your positioning pixel. This the root cause of your unwanted upper margin.
Your button has an odd pixel height (23px) which means it has a true center pixel- pixel 12. VB tries to position the image's center pixel (8) on top of the button's center pixel (12). This puts 8 of the image's pixels BELOW center, and 7 pixels ABOVE center. To even things out, a 1-pixel margin appears above the image.
The solution
Pad the image with 1 extra row of pixels on the bottom. The image now has a height that's odd (17 px), giving the image a true center pixel which can line up perfectly with the button's center pixel.
That's how I solved the problem for myself. However, a simpler possible solution just occurred to me. You could probably achieve the same result by assigning the image a bottom margin of 1px. I have not tested this solution but it seems theoretically equivalent to the first solution.
Additional note: Two objects of EVEN dimensions should theoretically be able to center-align perfectly. But strangely enough, the alignment problem occurs even if the button AND the image BOTH have even dimensions. (Apparently the compiler is not consistent in the way it determines the center pixel of one control vs another.) Nonetheless, in this case, the same solution applies.
Typically, we'll set the following properties (for an image on the right, for example):
ImageAlign: MiddleRight
TextAlign: MiddleLeft
You'll want to align both the text and image in a similar fashion. Outside of that, make sure that you are setting the Image property, not the BackgroundImage property and make sure you are doing the icon to plain bitmap conversion properly. Have you tried a plain bitmap file?
Just a question: are you positive that the bitmap contains no information on the top of the note image? I have had that happen to me more than once where a crop looked right in Photoshop and came out incorrect in the live code... :)
If that were the case your code may be perfect ;)

Resources