It is possible to use the SetWindowPos API on Windows to keep a windows always on top of other windows, and there are many questions on StackOverflow dealing with this.
It is possible to keep only part of a Window always visible? I.e. specify a clipping region inside an existing window, and keep only that part visible?
A use case would be the following (on Windows):
User clicks on icon to run app.
User highlights a portion of the screen to focus on (similar to the Snipping Tool on Windows 7)
The highlighted part of the screen remains always visible, even when other windows/programs are moved over the selected region.
I know the issues that would spring up with having other applications that are also set to being topmost. Just curious if this is even possible?
Even if you change part of your window to be transparent to what's below (with a clipping region) it's still going to take all the mouse clicks, etc. that occur over the transparent part.
Your best bet is to create a new smaller window and make it top-most while hiding the main one.
Related
For a small demonstration application, I want the option to delete file (from the files explorer on windows) by simple dragging it all the way to left/right side of the screen (the all desktop, not the application)
Is there a way to do it?
Thanks.
For demonstration purposes you could create a borderless always on top window that fills the entire screen and cut out a hole in the middle of it with a window region so you are left with just a 1 or 2 pixel wide strip on each side and set the opacity to 1 so it is basically invisible. You could then handle drops on the window.
On Windows 8 you might run into issues because it already uses the edges.
I don't believe this feature is useful enough to actually implement as a real product though.
I am trying to capture windows hidden behind my application. I am using windows 7 and VC++. I have tried printwindow() function which draws the both non-client and client area of hidden window, but captured window in the device context doesn't show desktop composition effects(aero effects). Instead it shows the captured window with windows 7 basic theme.
I have also tried with GetWindowDC() to retrive the DC of hidden window, and then Bitblt() it to memory DC but the captured window doesn't show non-client area (caption, close button, minimize button etc) correctly.
Anybody faced this issue?
Please help.
Click the link below. It leads to a MSDN site that lists all the existing Windows Functions ever of all history since Windows 95 up to Windows 8 (from period where Microsoft started Windows until present). It shows old windows functions of first Windows and new windows functions added for the new windows.
http://msdn.microsoft.com/en-us/library/windows/desktop/ff468919(v=vs.85).aspx
Anyway follow this site.
You will see the name of each function as a link.
Click any of them that you are interested.
Each link there leads to another MSDN site that explains all the basics knowledge that you must know about the function before using it, that you want to learn more. What that function does, its purpose, all its parameters and how to use each one, all their flags, all parameters types, return value and at last remarks section that shed more light and sometimes gives tips about the selected function.
Of course, you don't have to read all of them. Find in the list only the necessary functions to fit your needs. The functions that will solve your problem and answer your question that you posted.
By the way, I read your post, and I think that I found in the list the necessary functions that will do what you want to do, I will list them below, and say in one sentence what each does for what you need:
AnimateWindow - Enables you to produce special effects when showing or hiding windows. There are four types of animation: roll, slide, collapse or expand, and alpha-blended fade.
FlashWindow - Flashes the specified window one time. It does not change the active state of the window.
FlashWindowEx - Flashes the specified window specified number of times. It does not change the active state of the window.
Use these functions to achieve the aero effects that you want.
SetWindowPos - Changes the size, position, and Z order of a child, pop-up, or top-level window. These windows are ordered according to their appearance on the screen. The topmost window receives the highest rank and is the first window in the Z order.
Use this function to show the hidden windows on the top side (above all other windows) and on the screen front of you. The operating system will automatically draw the both non-client and client area of these windows without using any gdi, draw and paint functions yourself.
If you want these windows to return back to their previous state (where they were hidden), then save their state with GetWindowPlacement function and later call SetWindowPlacement to bring them back to their hidden state. You can try GetWindowRect and SetWindowPos instead to achieve the same goal.
I also think that you will be interested in GetWindowTheme and SetWindowTheme functions and all the draw theme functions (BackgroundEx, Edge, Icon, Text, TextEx).
There are more theme functions. Find in msdn and in other sites on the web.
My application is a Windows Forms one.
I tried using the windows wallpaper, but this depends on the "Fill", "Stretch", "Fit" or "Tile" settings.
I just need the image as it is on the desktop, but including the part "under" the taskbar, because this part is visible in case of transparent taskbar.
Why I need this?
Because I have a tray application which slides from under the taskbar when opening. And I need to set a mask there, so it can't be seen sliding, until it reaches the top of the taskbar. Again, this is only a problem when the taskbar is transparent.
I am not sure if I understood your question correctly. But to me, it seems that you need the image that has created wallpaper. If it seems easier, take a look at registry entries at following location:
HKEY_CURRENT_USER\Control Panel\Desktop
This will give you the path, size, tile/no tile etc. information for the wallpaper.
There is a Win32 function called PaintDesktop you could try but unless I'm misunderstanding things you should be able to just adjust the height of your window so it is never really behind the taskbar...
Why I need this? Because I have a tray application which slides from under the taskbar when opening. And I need to set a mask there, so it can't be seen sliding, until it reaches the top of the taskbar. Again, this is only a problem when the taskbar is transparent.
The problem here is that you're starting the slide up from the bottom of the entire screen, rather than starting from the bottom of the screen's working area (i.e., the top of the taskbar). That's why you're seeing the pop-up window slide up behind a transparent taskbar.
Luckily, the solution is much simpler than obtaining the desktop background and/or doing any type of masking. It's also much faster, and it's always good that your eye candy isn't unnecessarily taxing the user's computer.
All you need to do is determine the coordinates of the screen's working area, which is defined by Windows as the area that can be used by applications, not including the taskbar and other side bars. You can obtain this information easily in WinForms by querying the Screen.PrimaryScreen.WorkingArea property. This will return a Rectangle that corresponds to the primary screen's working area. Since you know that the taskbar is always displayed on the primary screen, this is exactly what you want.
Once you have the coordinates of the primary screen's working area, start your pop-up window's slide from the bottom of that.*
This is a good lesson of why you should always include an explanation of why you want to accomplish something. There's often an even better way that you haven't thought of.
*Of course, I'm ignoring the fact that a user might not have their taskbar positioned at the bottom of the screen. You can put it on either side or even on top. It sounds to me like you haven't considered this in your question, either. If this is an app that you're writing only for yourself or for a controlled environment where you can be sure that no one has their taskbar in non-default positions, that might be OK. But if you're writing software to distribute to a wider audience, you will need to take this into account. The rcWork coordinates will be correct, regardless of where the taskbar is positioned, of course, but you will need to know whether to start the pop-up window's slide from the bottom, the left side, the right side, or the top.
I'm trying to work out what the best way to draw over the top of all other items on the screen on OS X. I don't want to impede the user's ability to interact with their applications, but want to 'annotate' them. I want to be able to draw up to 20 different annotations. The top half of this screenshot from Gizmodo happens to nicely show the kind of thing I want to do. http://gizmodo.com/assets/resources/2006/07/04%20Safari.jpg (sorry, I'm too new to post it as an image)
The questions I think I need to answer are:
Should I create a single window for
each drawing and draw to that? If
so, how do I minimise overhead?
What kind of window or other context should I use given that I don't want any window
decoration?
I don't think I want the overhead of creating 20 windows, but I also don't know that I want to create a full-screen, invisible window that contains my context (I presume a subclassed NSView), because I fear that will a) cause problems interacting with what's below and b) break the niceties of only redrawing when necessary (my actual drawing will likely only cover 10% of the screen)
I've not worked with Quartz2d before, so I just can't get my head around how to get the 'right' context to draw on from the documentation. Any help would be appreciated.
Thanks,
Who
You can only draw into a window. You can make a transparent, borderless window but it will need to be at the front.
You could set it's level to something like NSPopUpMenuWindowLevel to make it draw above other windows (this will be very annoying to users) but clicking on it will:
a) activate and bring to the front your app
b) Prevent the app underneath receiving mouse events
Is that what you want?
We have a fairly complex GUI, so when certain windows are resized their Redraw() is set to false till the operation is completed. The problem with this is that if the OS "Show window content while dragging" setting is checked, when decreasing the window's size the windows behind it are not repainted. This means I have to force the repaint myself so the remains of the resized window are deleted. I have no problem getting the dimensions of the region that was uncovered. What I'm looking for is best way to cause all windows within that region to repaint their part.
Not being much of a GUI programmer, I can traverse the uncovered region and list the windows in it. Then, I can ask each one of them to repaint its part. But I'm quite certain there has to be a better way to do this...
It is worth mentioning the app is written in PowerBuilder. This means I can call whatever Win32 function I'd like, but have limited control over the GUI behavior and the message handling. If there's a better way to prevent the window's content resize from being visible, or there's a way to make a non-redrawn window clean after itself, I'd love to hear it (just have the limitations above in mind).
I'm curious what version of PowerBuilder you are working in? I do resizing all the time and never run into issues like you are describing.
Maybe you can lay out some more detail on why you need to set your redraws to false within the PowerBuilder environment.
Hope I can help.