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WPF - View getting minimized during navigation

I have a WPF application which behaves weird when another application is also opened. 'Another' application is developed using Panther. WPF apps behaves correctly with all other apps in the machine.
While both the applications opened, and when we click next on the WPF app, the app getting minimized even though its active as per windows active event.
WPF application is built using galasoft and follows slightly different approach in navigation compared to the pattern available when we search.
We initiate the Page from app.xaml.cs and based on the click, we invoke currentPage.Hide() and nextPage.Show() methods. All the navigations are written within App.xaml.cs file. Through a delegate the button click will be passed to app.xaml.cs file and the pages are switched.
Did anyone else face similar kind of issues?

Finally, I managed find an answer/work around to this issue.
In the existing design, the sequence of actions were Hide() the current view and Show() the next view.
Now, we modified the sequence to perform Show() the next screen first and then hide() the current screen. This way, the window was kept active and was visible to the user.

VS 2013 Quick Find loses focus when switching to my application - how do I preserve/restore it programmatically?

I have whipped up a C# clipboard application that stores multiple 'clippings' for later use. I use low-level keyboard hooks to pop open my application's window(s) on command. When the window is closed (or a clipping is double-clicked), it is supposed to paste the selected clipping into the last active window (the window prior to my application's window). I use low-level WINAPI methods to determine the last active application, snag its handle, and then return focus to it before simulating a Ctrl+V keystroke to paste.
This typically works except in one very unique scenario: I am in a WPF application project, Quick Finding in a XAML file, the cursor automatically switches to the body text, not the Quick Find textbox, and pastes it there. It seems to have something to do with the loss of focus/activation, as it moves the cursor whenever I activate another window, regardless of my own application's running.
VB files, C# files, what have you, and XAML opened in WinForm projects do not steal the Quick Find focus when switching between the VS2013 application and my own; upon returning to the last active application, the text pastes into the Quick Find box.
Only the XAML in WPF application projects gives me this problem.
So far. I know it is a fringe case, but I expect to run into more. This program is meant to be used in a coding environment and it's pretty important that it be able to handle these kinds of scenarios.
I've tried getting the internal control handle using code from http://www.codeproject.com/Articles/34752/Control-in-Focus-in-Other-Processes, so that I can return the focus to it, but it seems that the handle for the body text and the handle for the Quick Find text box are the same.

A partial solution is found in: How do I prevent the original form from losing focus when I show another form? The popup window I use is navigated primarily through my low-level shortcuts, and therefore has no need of explicit activation.
Using the mouse on it or any of my other windows (as I expect my users will sometime), will cause it to gain activation and circumvent this fix. However, it's such a fringe case it doesn't seem to matter. Hopefully this helps anyone in a similar situation (if not necessarily specifically this one).

Custom search tab in Windows start menu search with C#

I am interested to know how can I do the same thing that the apllication listed below does:
Start Menu Calculator
I want to know how can I create an custom tab in Start Menu Search and then handle it with my WPF application. It should only be enabled until my application is running.( Just like what The calculator does )
I read something about windows API Code Pack and I downloaded it but I don't know how can I use it. I searched through it but I didn't find anything.( If you know how I could do this using with Windows API Code Pack, please write an example that explains how to do it in C#)

The main exe "Start Menu Calculator.exe" installs a windows hook (using SetWindowsHookEx) into explorer.exe. The hook is implemented as usual in SBLib.dll which is then injected into Windows Explorer's memory space.
This hook searches for window handles belonging to the search box. See a discussion around this here:
How do I get a "handle" on the Windows Search textbox? and probably sub classes the search box windows (if you kill the "Start Menu Calculator.exe" process abruptly, it crashes Windows Explorer too... which kinda confirms this)
It then reacts to key presses, and I suppose it butchers up the result window. In the hierarchies of Windows, I think it's a Window named "Desktop Search Open View", you can get to it with SPY++ under "Start Menu", aside the windows mentioned in the msdn forum above.
So, no nice API behind this nice application. Massive hacks instead :-)
I think however, some level of integration is possible, using documented behavior, with the search box. I have not dug further, but there is the notion of federated search in Windows (Windows 7 Federated Search). I don't see if this would be capable of reacting instantaneously to what the user types in though...
As a side note, if you're also looking for a way to run javascript code from C#, there is a question here on SO that says it all: parse and execute JS by C#

When making Start Menu Calculator I initially tried to use federated search and Managed (.NET) code however you can't integrate into the start menu, only the shell search (for web service based search which lets you return custom results based on a search string). The problem is that the federated search is structured such that all the search data is pre-indexed so for the calculator to work I would have had to pre index every possible calculation! The reason it all works this way is to make sure that clicking the start menu is always fast and responsive (you don't want a web service call everytime you press start in the shell).
I ended up hiring someone to write a native windows app that places a IE control into the Start menu search area and passes the searched text in with the source. All the visual stuff is just css made to look like the start menu rendering and the calculations handled in javascript.
So yes, a bit of a hack but it seems to work and I havent had/heard of any crashing issues so far.

I want to drag an image from a Silverlight UIElement and drop it on the users Desktop or Windows Explorer

I have a Silverlight control containing an image. I want the user to be able to drag the image out of the Silverlight application and drop it anywhere they would be able to drop an image. For example, to the Desktop or to a PowerPoint slide or Word document. Everything that I have read thus far says it cannot be done but I find that hard to believe. I'm very new to Silverlight and RIA development so any help would be much appreciated.
Below is the code sample in my WinForm Form but the drag never starts.
string[] aString = { imagePath };
DataObject data = new DataObject(DataFormats.FileDrop, aString);
data.SetData(DataFormats.StringFormat, imagePath);
DoDragDrop(data, DragDropEffects.Copy);

Well the trouble is that a drag operation in Silverlight doesn't have simple access to anything outside the browser (by design). Depending on the user's settings you even have to get explicit permission for clipboard operations and sandboxed temporary file storage. This really sounds like a task better suited to a WPF application (perhaps with web deployment?) or some other desktop application technology.
However, that being said here are some things you could try/consider:
Silverlight/Javascript/ActiveX combination hosted in Internet Explorer
Silverlight 5 "Out of Brower" & P/Invoke (I heard P/Invoke will be supported when Silverlight 5 comes out)
Silverlight connecting to a web service running on the same computer (crazy, but you didn't ask for "not crazy", you asked for possible)
I am not very familiar with drag and drop in the Win32 API so it would take a lot of research and experimentation before I could confirm that this was even possible (and I can already tell you it isn't practical).
Edit: Based on the extra information you provided about the question I suspect it is possible to do what you are attempting. First, are you using WPF or WinForms? I assume WPF but one of your comments says WinForms. I wasn't very familiar with WPF drag/drop operations, but having looked into it, I think your code is on the right path. I created a WPF application and initiated a drag during a KeyDown event. This meant that the mouse button was not necessarily pressed. If I initiated the DragDrop while the button was down it worked. If I initiated while the mouse button wasn't down, I had to push the mouse button down and the drag operation would start (this was unexpected since I assumed the mouse would have to already be down). If I pressed the mouse down outside the application, then gave the WPF app focus (ALT+Tab), then initiated the DragDrop while the mouse button was still down, it didn't work. I got a reference to the MouseDevice and checked the LeftButton property, and the state was showing as "Released" even though the button was still being held down. It seems the key here is the way drag/drop interacts with internal mouse state. You might have to find a way to set the mouse state (maybe with the UI Automation API?). At this point it should be painfully obvious that this whole thing is a hack (even though it is probably possible to get it to work somehow).

The solution we came up with was as follows. The RIA i.e. Silverlight sends a message to our Desktop application WinForms with the path of the image to drag along with the bounding rectangle in screen coordinates that we want to start the drag from. The Desktop code creates and places a Panel over the area that we want to drag from. This panel is where we use DoDragDrop to initiate the native drag when the user left clicks. Since this panel is placed outside and above the silverlight control, everything works perfect. Sandbox defeated.

I have been working on some Silverlight apps for the past few months and fully investigated your exact requirements only to find it was not possible. I believe you can drag from the file system, from Silverlight control to control, but not to the file system.
Does Silverlight 4 support drag and drop from app to desktop?
http://msdn.microsoft.com/en-us/library/dd772166%28v=vs.95%29.aspx

Can I use window hooks in C# to determine if a window gains or loses focus?

I've written a c# application which automates an instance of IE. I'd like to know when internet explorer gains focus and when it looses focus.
From the SHDocVw.InternetExplorer object I can get it's HWND. From there how can I create a message hook to receive WM_KILLFOCUS and WM_FOCUS events (assuming those are the correct events to be listening for :))?
Thanks everyone!!
UPDATE: I found a way I could use to accomplish the above goal without using hooks (which I haven't quite figured out how to do in c# yet), using the .NET framework in this question.
The problem with this code
AutomationFocusChangedEventHandler focusHandler
= new AutomationFocusChangedEventHandler(OnFocusChanged);
Automation.AddAutomationFocusChangedEventHandler(focusHandler);
is that it is easy for a window to be the foreground window and that event won't fire when that window is switched to because it's waiting for a specific UI Element to be in focus. (To test this you can use a function that uses that code and prints a message everytime a new window is in focus, such as the MSDN sample TrackFocus, and then click on a webbrowser. When most webpages or a blank page is being displayed in the browser the event wont fire until the address bar or some other element is selected.) It could probably work if there was a way to modify so that it could throw the event if either no UI Element is in focus or every time an element lost focus (instead being thrown when it gains focused). Anyone have any ideas on how I could fix the above code to solve my problem?
Update 2: I just came across this (article claims you can only hook to mouse and keyboard from c#) as well which may mean I can't use hooks at all for what I'd like to do.

Detailed instructions on setting up a hook from C# are here: http://support.microsoft.com/kb/318804/en-us?fr=1