Why are some items greyed out in Spy++'s Windows view? - windows

To modify a window of another program, I need to find a specific SysTreeView32 in it using EnumChildWindows API call.
When I inspect the window using Spy++, there are a number of SysTreeView32's in it but all are greyed out except one, which is the one I'm looking for.
The following picture is an example of grey items:
Why are the shown items gray and what API call does Spy++ use to know whether it should grey out an item or not?

Those are just non-visible windows - ie HWNDs that don't have the WS_VISIBLE style bit set. They are often worker windows - windows that just exist to process various messages in the background - or in some cases are UI that's yet to become visible. For example, a window that lets you hide or show a toolbar may just hide it by making it invisible rather than destroying it and recreating it later.
In your specific case, the WorkerW could be a placeholder for some other piece of UI that's not needed right now, while the msctl_statusbar32 looks like it's a hidden status bar.

Related

How to get correct background and control colors in property pages?

I'm trying to handle background color properly in a dynamically generated property sheet in dynamically generated property pages in win32 api using MFC (though I expect my question is general, and not restricted to MFC, but since my code and examples use it, it's germane to my question anyway).
So we have a:
CPropertySheet
containing multiple
CPropertyPage
I generate the contents of any given page dynamically - from file resources using a custom dialog definition language - all irrelevant other than to say - a list of controls and their coordinates is created within a given page, and the page is resized to accommodate them. This logic is working beautifully.
However, what doesn't work is that the controls and background of each page draws using the dialog default color/brush.
I've tried a number of ways to attempt to force it to draw using the white color/brush that a hard-coded property sheet / page would.
There are two important pieces to this:
Page Background
Control (on the page) background
For #1, I've tried:
acquire the background brush from parent window class (it's dialog bkgrd) (same is true if I do this and ask the tab control)
change the property page to use WS_EX_TRANSPARENT (PreCreateWindow is not called by the framework when generating a page viz PropertySheet::AddPage)
For #2, I've tried:
overriding OnWndMsg / WM_CTLCOLORSTATIC to forward that request to (A) the parent (sheet), and (B) to the tab control (which is what wants the white in the first place).
However, anytime I use any of the above "ask for the background / forward the request" up the chain to either the sheet or the tab control - I get the dialog background color, never the white I'd expect.
Using Spy64, I can see that for a fully hardcoded property sheet / page - that the only discernable differences I can see is that the dialog window created in AddPage (or its moral equivalent) has WS_CHILD instead of mine which has WS_POPUP (the rest of the styles appear to be the same, such as WS_VISIBLE|DS_3DLOOK|DS_FIXEDSYS|DS_SETFONT|DS_CONTROL and WS_EX_CONTROLPARENT.
So, other than the WS_CHILD, I see no significant differences from what I'm creating and from another property sheet that works properly from a standard resource (i.e. hard coded).
I'm also flummoxed as to how this works normally anyway - since forwarding things like the ctrlcolor message doesn't respond correctly - and asking for the windows background colors similar doesn't - then how is it in a standard case the background colors of controls and pages comes out as white, and not dialog background?
Any ideas or help would be appreciated - I'm kind of running out of ideas...
When Visual Styles were added in Windows XP they really wanted to show off this new feature so they made the tab background a gradient (really a stretched image) instead of a single color and this caused problems in old applications that did custom drawing with the dialog brush as the background.
Because of this, only applications with a comctl32 v6 manifest got the new look but there was a problem; old propertysheet shell extensions would load in new applications (including Explorer) and things would look wrong.
To work around this they also require you (or your UI framework) to call EnableThemeDialogTexture(.., ETDT_ENABLETAB) to get the correct tab page look.
As if things are not tricky enough, there is a undocumented requirement that you also need a button or a static control on the page!
If you have custom controls they have to call DrawThemeParentBackground when you draw if they are partially transparent.
Turns out my old code had defined an ON_WM_ERASEBKGND handler - and removing that (and all of my above attempts) makes it work.
So simply doing NOTHING is the correct answer. D'oh!!!
I'm leaving my shame here in case someone else trips on this! [Whoops!]
(Still interested if anyone has deeper insight into how this mechanism works under the hood)

How can i draw to or add a custom button to every window of all applications?

I have seen several tools adding a custom button and/or drawing on the title bar of all windows of all applications in Windows. How is that done?
Extra points for an example in Delphi.
EDIT:
I found something for dotNET that does this:
http://www.thecodeking.co.uk/2007/09/adding-caption-buttons-to-non-client.html#.VdmioEDenqQ
How I see this job:
First of all we should be able to paint this button on the our own window caption. This procedure will be used later
This part of the program enumerates the active and visible windows
This part of the program using injection attach our dll to enumerated windows
From injected dll we can draw the button on the window caption
Inside this dll we should process the click on the button
We should have mechanism to send result to our main program
I haven't done this, so the following is what I would investigate if I were to try:
For each application / each top-level window:
Create a floating window and position it over the title bar wherever you want it to sit. Set up the parent / child relationship, but this window is part of your own process. (There are occasionally problems parenting a window from one process to one from another process, but try. I'd avoid injecting into other processes if possible.)
You can investigate the window flags to see if the window has a title bar (ie if you should add a button) via GetWindowLong with GWL_STYLE looking for WS_CAPTION. The same call will also let you see the type of caption / frame, which you can combine with GetSystemMetrics with, eg, SM_CYDLGFRAME to figure out the right size for your button on this specific window's title bar.
This window is now your button: paint, handle clicks etc as appropriate.
Make it a non-focusable window so that clicks to it don't take focus away from the window is is on the title bar of. You don't want clicking it to make the title bar change colour, for example. Do this by setting the WS_EX_NOACTIVATE window flag, something like: SetWindowLong(Handle, GWL_EXSTYLE, GetWindowLong(Handle, GWL_EXSTYLE) orWS_EX_NOACTIVATE).
The main problem is to keep it positioned correctly when the window moves, is resized, etc. To do this, install a hook for the system move events. You can also hook minimize and restore via EVENT_SYSTEM_MINIMIZESTART and EVENT_SYSTEM_MINIMIZEEND. This will allow you to keep track of all windows moving around onscreen, such that you can adjust the button-window position if necessary.
That gives you a window which you can paint as a button (and respond to clicks etc), that visually is "attached" to other windows so it stays in the same place as the user drags the title bar, minimizes or maximises the app, etc, and that is in your own process without cross-process problems.

Capture Hidden window with aero effects

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.

Keep part of a window always visible

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.

Get Context Menu text of specific TaskBar button

I've got some code that grabs the TaskBar buttons and their text from the windows TaskBar using User32.SendMessage with the TB_GETBUTTON message to retrieve a TBBUTTON structure (Win32 API via C# P/Invokes). But I'm trying to figure out how to then, once I have the handle to the button, grab the associated context menu text. There is some status information on there for a specific application that I would like to retrieve. The button text gets me some of it, but I need to the context menu text to complete it.
Any ideas?
This is not completely clear... Context menus don't have text, as such - they have menu items, each one of which will have text. By "context menu text", do you mean the text of the menu items in the taskbar button's popup/context menu? For example, "Restore", "Minimize" etc in the screenshot below?
If so, I suspect you're going about this the wrong way:
This menu doesn't belong to the button, but is the system menu of the window represented by the taskbar button. If the button has a context menu, this is probably for a grouped collection of windows, not one specific window (or even windows for one process.)
Making judgements based on the context menu of a window sounds like a dodgy approach to me, especially based on text since that will change depending on where in the world your user is located. Applications can also change the contents of this menu so there's no guarantee it will contain something you expect to be there. It would be better to check the window style, if it's minimized, etc, to find out the information that also affects the contents of the menu.
I'm going to answer this based on what your needs seem to be from the question, not what you've directly asked, since (a) it's not possible as asked and (b) I think you're trying to do something else. (As a general guideline, in a question it's good to state why you're trying to do something - and even maybe ask about that, ie 'how do I achieve X' - in case there's a better method than the one you're using. Here, X is probably 'find out information about this window' not 'get the text of the context menu', because that's probably only one possible method to get to X.) Also I think extracting data from the internals of a third-party application like Explorer (the taskbar is an Explorer window) is fragile and prone to break in future versions of Windows.
The system menu or window information (whichever one) belongs to application windows. Unless taskbar buttons are grouped (and then it's the subitems) one taskbar button corresponds to one specific window in the system. So what you want to do is find these windows. You do this by:
Using the EnumWindows function
Then for each window that is passed to the callback, checking the extended window style using GetWindowLong with GWL_EXSTYLE to see if the WS_EX_APPWINDOW bit is set
In addition, sometimes other windows are shown: these heuristics should help.
Each one of these windows is a window that should appear on the taskbar, Alt-Tab dialog, etc.
You say you're getting the text of the taskbar button - this is probably the window caption of the window, and GetWindowText is the canonical (read: probably a lot more reliable) way to get the caption of a window belonging to another process.
If you really want the popup menu, then:
Use GetSystemMenu to retrieve the handle for the system menu for the window. Applications can customise this, so if your app is doing this (and that's why you want the popup menu) ensure you pass false to the bRevert parameter
You can then get the number of menu items using GetMenuItemCount and for each one call GetMenuItemInfo to get info about each menu item. Pass true to the fByPosition parameter to indicate you're accessing the menus by position (since you know the count, you're getting item 0, 1, 2... count-1).
This fills a MENUITEMINFO structure, which (I think, I haven't ever had to code this so I haven't tested) will tell you the text associated with an item via the dwTypeData field "if the MIIM_STRING flag is set in the fMask member".
If you really want information about the window status, you can get this information using methods like IsIconic to see if it's minimized, GetWindowLong again to get other information, etc. I'd suggest you ask another SO question about how to get whatever specific information about a window for details.
Hope that helps!

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