Hello dear stackoverflow friends
A few months ago I asked you a question about QuickAccess (Pin/Unpin). Unfortunately we are still facing this issue (Unable to unpin virtual objects). After having called Microsoft Support a few times, they replied us we should subscribe to premier support... Too expensive for a small company.
So we have decided to Mimic the Windows 7 Favorites in our Shell Namespace Extension.
No big deal in the Explorer, calling ShellExecuteEx with view's handle and lnk's target object absolute pidl works like a charm.
Too good to be true, yeah, as it is not working as expected in IFileDialogs...
First the lnks (wrapped in a virtual object, but parsing name is Filesystem Path) weren't for obvious reasons shown in the dialogs. So we tried with attributes such as "SFGAO_FOLDER", "SFGAO_FILESYSANCESTOR" etc. but then the shell was calling IShellFolder's EnumObjects and that's not what we want.
So we decided to have a go with the Interface IObjectWithSite, implementing it in our Favorites' folder. We were then able to consume events from IFileDialogs such as OnSelectionChange. Then we tried the same method as in the explorer, getting view handle (first querying IOleWindow interface, getting window handle, creating view in parent IShellFolder using window handle) and calling ShellExecuteEx... And the result is.. A big application (Notepad, Word etc.) crash and a new Explorer Window with the right virtual object selected.
Probably is my approach too complicated, have you got any ideas?
Thanks a lot!
Thank to Simon, I was able to find a solution, still work in progress. The issue is that the IContextMenu, IContextMenu2 and also IContextMenu3 interfaces are implemented in the solution. On Windows 7, the .lnk menu handler was called, fine, on Windows 10 on the other hand you need to call SHCreateDefaultContextMenu, then merging the menu handlers (SHCreateDefaultContextMenu will then Call IShellFolder::GetUIObjectOf with IID_IQueryAssociations). So the code was dated... Thanks!
Related
My custom Windows shell context menu handler works like a charm, for all Windows versions from XP to 7, but on Windows 8, 8.1 and 10, installing it breaks the Win+X menu (sometimes called "Power user menu", or "Quick Access menu", or "WinX menu"): when hitting Win+X, the menu is displayed as expected, but its items do not work anymore (nothing happens when I click on them), except for the last four items at the bottom which still work as expected ("Search", "Run", "Shut down/Sign out", "Desktop"):
I quickly found out on Google that it was a well known issue for a great number of shell extensions that were not "compatible" with Windows 8/10. But sadly, I only found application users talking about this issue and its "solutions", and no developer talking about this. And the two "solutions" proposed by these users were:
Unregistering this shell extension
Uninstalling the app that registered this shell extension (which leads to solution 1...)
See for example this, this, or this to read people talking about this issue.
Note: my shell extension is applied for the * file type, which means all files.
Several days later, I found the cause of this issue in the shell extension source code, so I thought it would help other developers to share it on StackOverflow, as a self-answered question (I didn't find this question). See answer above.
I first looked at the shell extension sample code provided by Microsoft (which doesn't cause this issue), compared it with my code, and progressively replaced parts of my code with Microsoft's code and testing it after each replacement.
I found out that what prevents power-user menu to work is what you return in method InvokeCommand() from IContextMenu interface: if your extension cannot handle the given verb, it shall always return E_FAIL so that Windows tries with other implementations of IContextMenu (see Microsoft documentation for more details). It seems that when a power-user menu item was clicked, Windows first called my extension (* file type), then since it didn't return E_FAIL for this unknown verb, Windows thought that my shell extension has processed this event, so it didn't process it through the nominal power-user menu callback.
By the way, three things seem very weird to me:
Why does Windows even try to process this power-user menu event with a shell file extension? Is this menu coded using the same design/mechanism as any other Explorer's file contextual menu?
Why does this bug didn't produce more side-effects yet? I mean this should have broken the whole shell extension system right from the beginning, no?
Why do so many applications has this bug? (meaning why so many applications do not return E_FAIL as expected?). It's been a while now that I've written this code, I can't really remember where it comes from, but I guess it comes from a Microsoft sample or any Microsoft employee tutorial (far too Microsoft-oriented to be coded by yourself). If it's the case, that may answer the question why so many shell extensions cause this issue...
I would be interested if someone has some ideas to share about this subject!
By the way, I hope my post can help other developers. When looking at the new Microsoft example that works like a charm, I was first afraid having to rewrite all my shell extension from their sample without knowing what was wrong in my code!
I am writing an Explorer extension for Vista and Windows 7. I read that if you are making a namespace extension you can provide your own commands using IExplorerCommandProvider. This is done in response to IShellFolder::CreateViewObject.
I am not writing a namespace extension, but a toolbar that lets you perform operations in Explorer. So I need to get IExplorerCommandProvider from an existing IShellFolder.
I get IShellView from the IShellBrowser, then I convert it to IFolderView, then I get IShellFolder. So far so good. I get a valid folder pointer.
This however doesn't work:
pShellFolder->CreateViewObject(NULL,IID_IExplorerCommandProvider,&p); // returns E_NOINTERFACE
I tried passing different values for the hwnd parameter of CreateViewObject, starting with the file pane and going all the way up to the top level Explorer window, and none of them worked.
So my questions are:
1) Do regular file system folders even support IExplorerCommandProvider?
2) If they do, how do I get my hands on that interface?
Thanks
Ivo
We have a legacy VB6 application which has worked just fine on Windows XP Professional SP 3 until just recently when we added an IE frame control so that we could display static local HTML files on a form. And, it works fine until I go to close the application. And, then it reports the following error message (consistently):
Faulting module ntdll.dll, version 5.1.2600.5755, stamp 49901d48
Here's the reference in the Visual Basic project file:
Object={EAB22AC0-30C1-11CF-A7EB-0000C05BAE0B}#1.1#0; ieframe.dll
And we use it by performing the following actions:
Development machine is running Win7 + Vb6 IDE.
Add a component reference to the "Microsoft Internet Controls" located at C:\Windows\SysWow64\ieframe.dll
Place a control on the form at design time.
Show that form modally by calling Form.Show vbModal The error happens when I use the default form instance frmMyForm.Show vbModal as well as when I use a local instance Dim MyForm as New frmMyFormMyForm.Show vbModal
Call WebBrowser.Navigate "staticPage.html"
When the user presses a button, the button click event returns the user choice and the form is disposed of.
Exit the application -- Here's where I get the error.
I've been looking all over the web, and haven't been able to find a whole lot of people still trying to use VB6 in this way. So, I'm wondering if someone might be able to help me on stackoverflow. Any help is much appreciated!
[Update] And, the plot thickens. I made a sample application with just that web component in order to make sure that it was causing the error. But, I didn’t experience the error when it closed like I was when exiting our existing/legacy vb6 application. I'll do a bit more investigating.
A follow up to this in case any runs into the same issue (the original poster and I were coworkers at the time)...
The application was using the VBCorLib library, and some of its string manipulation classes utilized direct memory access incorrectly. Read more at this VBCorLib forum post.
It turns out that the issue was that I was trying to delete the temporary file that the browser had loaded. It works now that I've moved that delete file code to the form unload event.
I'm working on a little macro record/replay tool which can automate a few very old Visual Basic 6 GUIs we have. To do so, I'm identifying the controls by their name (the value of the name property of a control, that is).
One part of this tool needs to determine the name of a control given its HWND. For newer Visual Basic applications which were done using VB.NET, I can use the WM_GETCONTROLNAME window message. This works nicely.
However, this message is not understood by older windows. Is there any way to do this for controls of Visual Basic 6 applications? A solution which does not require being in the process of the GUI would be preferrable, but if I had a solution which only works inside the GUI process then that would be acceptable as well (since I can do the injection myself).
UPDATE: One thing I just tried, this moderate success: I used the AccessibleObjectFromWindow to check for implementations of the IAccessible interface of the object which shows the given HWND. In case I get an implementation (it seems that many [all?] Visual Basic controls implement this interface), I use the accName property to read out the "accessible name". Sometimes this does yield a useful string, but usually it doesn't.
I believe the only way would be getting inside the process and obtaining a pointer to the Form object, yet I have no idea how to do it from outside.
Is it possible you add support for the WM_GETCONTROLNAME to those older applications?
Or maybe, you could identify the controls by some other, natively-available properties?
Other that that, as Raymond is saying, there isn't much you can do.
Can you modify the vb6 apps? if so in each form load event you could iterate me.controls and use the SetProp(ctrl.hwnd, "MYNAME:" & ctrl.name, 0) api to add the name to the window's own property list, then in your other app you can EnumProps(ctrl_HWND) looking for the one that begins with MYNAME: and parse out the value.
I am trying to build my own little toolbox for Vista.
One of the features is a "window placeing tool" which places the windows at saved position. Another tool I could imagine are extensions to firefox or thunderbird...
For these tools to work, I need them to be able to capture "Events" in Vista.
To give you a concrete example:
Explorer Opened New Window
User started Firefox
Mouse moved
For the mouse case, there are some examples for C#.
I also know about the directory watcher, nice little helper.
Want I now need is the "new window opened event"
Any idea how to monitor this, without iterating the current window list every 5 seconds (I already know how to get Windows using the DLLImports, and getting Processes using managed code. But I have no Event when the explorer process opens a new windows)
Thanks for your help,
Chris
What you're talking about doing is not simple by any stretch.
You're going to need to register a hook, and you're going to have to build a callback procedure that gets called within another process's execution context -- this is not going to be .NET code (probably C instead), and will have to be in a DLL. That callback procedure will get called every time a certain class of events happens. It will examine the events it receives and filter out the ones you're interested, then send your application the notifications you want (probably via PostMessage). You'll then tap in to your application's main message loop to intercept those messages, and from there you can fire a .NET Event, or whatever you want.
Writing hook callbacks is tricky stuff because the code gets run within another process, not your own, and the memory management and concurrency issues take a bit of forethought. For that same reason, it's not going to be done in C#. Ideally, though, this callback code will be very small and very fast, since it's going to get called so often.
Also note that while perfectly "legal" in Win32, these system hooks have an immense amount of power and are commonly used by malware to change the way your system works. For that reason, you may run afoul of antivirus software if you attempt to do this sort of thing on a customer's computer.
Also note that the far-reaching effects of system hooks also means that simple programming mistakes can take down your whole system, which you will probably discover for yourself at some point while debugging; so save everything before you hit "run".
Good luck!
EDIT
Did a bit more search to see if there's any way to write the hook proc in C#, and came up with this:
How to set a Windows hook in Visual C# .NET
This is almost what you're looking for, but not quite. Hook procedures can either be global (which means that they run on every application) or thread (only runs within your application). The document states that:
Global hooks are not supported in the .NET Framework
Except for the
WH_KEYBOARD_LL low-level hook and the
WH_MOUSE_LL low-level hook, you cannot
implement global hooks in the
Microsoft .NET Framework. To install a
global hook, a hook must have a native
DLL export to inject itself in another
process that requires a valid,
consistent function to call into. This
behavior requires a DLL export. The
.NET Framework does not support DLL
exports. Managed code has no concept
of a consistent value for a function
pointer because these function
pointers are proxies that are built
dynamically.
Which means, again, to monitor things that go on outside your application's view, you need to set a global hook, which can't be written in .NET.
I have exactly the same issue as this, and I think I have a workable solution. Initially I looked into a similar option to the one mentioned by 'tylerl'. In my case however, instead of using 'SetWindowsHookEx', I attempted to use the similar function 'RegisterShellHookWindows'.
Unfortunately, this only succeeded in providing me with notifications of when a subset of windows are created/destroyed. The only windows which it provided notifications for are those shown on the taskbar.
Since I didn't fancy hacking into other processes, or writing the native code which would be required for SetWindowHookEx, I tried digging into the .NET automation APIs introduced in .NET 4.0, and I think this has the answer to your problem (at least as far as detecting when windows are opened / closed).
Here's a code snippet for using this API to detect windows being opened/closed:
using System.Windows.Automation;
private void StartMonitoringForWindowEvents()
{
Task.Factory.StartNew(() =>
{
AutomationEventHandler windowOpenedHandler = new AutomationEventHandler(OnWindowOpened);
System.Windows.Automation.Automation.AddAutomationEventHandler(
WindowPattern.WindowOpenedEvent, AutomationElement.RootElement,
TreeScope.Descendants, windowOpenedHandler);
});
}
private void OnWindowOpened(object source, AutomationEventArgs eventArgs)
{
try
{
AutomationElement sourceElement = (AutomationElement)source;
string message = string.Format(
"Automation.WindowOpened PID: {0}, Handle: {1}, Name:{2}",
sourceElement.Current.ProcessId,
sourceElement.Current.NativeWindowHandle,
sourceElement.Current.Name);
Debug.WriteLine(message);
// for each created window, register to watch for it being closed
RegisterForClosedWindowEvent(sourceElement);
}
catch
{
}
}
private void RegisterForClosedWindowEvent(AutomationElement element)
{
try
{
string elementName = element.Current.Name;
int processId = element.Current.ProcessId;
int nativeHandle = element.Current.NativeWindowHandle;
AutomationEventHandler windowClosedHandler = new AutomationEventHandler(
(ignoreSource, ignoreArgs) => OnWindowClosed(nativeHandle, processId, elementName));
System.Windows.Automation.Automation.AddAutomationEventHandler(
WindowPattern.WindowClosedEvent, element,
TreeScope.Element, windowClosedHandler);
}
catch
{
}
}
private void OnWindowClosed(int nativeHandle, int processId, string elementName)
{
string message = string.Format(
"Automation.WindowClosed PID: {0}, Handle: {1}, Name:{2}",
processId,
nativeHandle,
elementName);
Debug.WriteLine(message);
}
You will need to add a reference to the assemblies 'UIAutomationClient' and 'UIAutomationClientTypes'.
Here's a link to the MSDN documentation (you'll probably particularly want to take a look at the information on events):
http://msdn.microsoft.com/en-us/library/ms747327.aspx
Important implementation Notes:
1.) Notice that in the sample, I used a task factory to register for reception of the automation events. It's particularly important to avoid using the UI thread when registering for automation events or generally interacting with the automation APIs. Doing so can (and usually quickly does) result in a deadlock. Therefore, I use the task factory to ensure registration is done via the thread pool.
This also means, that the events will be received on the thread pool... So, if you need to perform any UI updates, you will have to marshal these across to the UI thread.
2.) You'll also note, that I capture any needed information on the element which may be closed, at the time of registration (using a closure). This is because, once the element is closed, we will no longer have access to this information - since the element has been destroyed.
Phil
The answer is not C# (or .Net) specific. You'll need to call SetWindowsHookEx( WH_CBT, ... ). This will allows to know when a window is created, destroyed, moved, sized, etc. You'll also need to get the relevant information from the window to identify if its one you need to do something about. Perhaps GetClassInfo, GetWindowLong, and GetWindowText.
The problem with the SetWindowsHookEx is that in order to get events from every window you need to have a separate win32 dll with the function in question exported. Although you might have success with the procedure outlined here.
To expand upon Joel Lucsy's answer, you need to use the Win32 API. However, there's a nice library, the Managed Windows API, that provides an object-oriented wrapper over common APIs. It may have what you need.