Develop Reference

WPF Live-Regions just for Narrator?

I have a textblock (ContentTextBlock) with AutomationProperties.LiveSettings="Assertive". I'm just testing and checking how useful this feature is. And... am disappointed so far.
private void Button_Click(object sender, RoutedEventArgs e)
{
ContentTextBlock.Text += " test";
var peer = UIElementAutomationPeer.FromElement(ContentTextBlock);
if(peer == null)
{
peer = UIElementAutomationPeer.CreatePeerForElement(ContentTextBlock);
peer.RaiseAutomationEvent(AutomationEvents.LiveRegionChanged);
}
peer.RaiseAutomationEvent(AutomationEvents.LiveRegionChanged);
}
When using Narrator, this works as advertised. Whenever clicking the button, Narrator announces the TextBlock text ("test" "test test" "test test test")... But when I use NVDA or JAWS, nothing happens, although the screenreader versions are relatively up-to-date. Did they really not add any support for live-regions or am I just missing an important point?

Whilst I didn't manage to get live regions to work, I found another workaround:
Tolk by Davy Kager
Tolk is a library which can, among oterrs
Detect which supported screen reader, if any, is running
Pass strings to the screen reader's speech engine and braille.
Also has support for SAPI
To include Tolk in your C# project, download it from the link above, then include tolk.cs (from src/dotnet) in your project, and place tolk.dll (it's found in bin) in the folder with your executable (or somewhere in the PATH variable). Make sure that the dll version matches your CPU target (x86/x64). Do the same for the dlls in the lib directory. Then you can use it according to the code found in the examples folder.
PS. Tolk works on Win 7 as well, so that's a bonus. The live-regions of WPF were only supported from Win 8 on.

c# customizing controls on a save dialog -- how to disable parent folder button?

I am working from the sample project here: http://www.codeproject.com/Articles/8086/Extending-the-save-file-dialog-class-in-NET
I have hidden the address/location bar at the top and made other modifications but I can't for the life of me manage to disable the button that lets you go up to the parent folder. Ist is in the ToolbarWindow32 class which is the problem. This is what I have at the moment but it is not working:
int parentFolderWindow = GetDlgItem(parent, 0x440);
//Doesn't work
//ShowWindow((IntPtr)parentFolderWindow, SW_HIDE);
//40961 gathered from Spy++ watching messages when clicking on the control
// doesn't work
//SendMessage(parentFolderWindow, TB_ENABLEBUTTON, 40961, 0);
// doesn't work
//SendMessage(parentFolderWindow, TB_SETSTATE, 40961, 0);
//Comes back as '{static}', am I working with the wrong control maybe?
GetClassName((IntPtr)parentFolderWindow, lpClassName, (int)nLength);
Alternatively, if they do use the parent folder button and go where I don't want them to, I'm able to look at the new directory they land in, is there a way I can force the navigation to go back?
Edit: Added screenshot

//Comes back as '{static}', am I working with the wrong control maybe?
You know you are using the wrong control, you expected to see "ToolbarWindow32" back. A very significant problem, a common one for Codeproject.com code, is that this code cannot work anymore as posted. Windows has changed too much since 2004. Vista was the first version since then that added a completely new set of shell dialogs, they are based on IFileDialog. Much improved over its predecessor, in particular customizing the dialog is a lot cleaner through the IFileDialogCustomize interface. Not actually what you want to do, and customizations do not include tinkering with the navigation bar.
The IFileDialogEvents interface delivers events, the one you are looking for is the OnFolderChanging event. Designed to stop the user from navigating away from the current folder, the thing you really want to do.
While this looks good on paper, I should caution you about actually trying to use these interfaces. A common problem with anything related to the Windows shell is that they only made it easy to use from C++. The COM interfaces are the "unfriendly" kind, interfaces based on IUnknown without a type library you can use the easily add a reference to your C# or VB.NET project. Microsoft published the "Vista bridge" to make these interfaces usable from C# as well, it looks like this. Yes, yuck. Double yuck when you discover you have to do this twice, this only works on later Windows versions and there's a strong hint that you are trying to do this on XP (judging from the control ID you found).
This is simply not something you want to have to support. Since the alternative is so simple, use the supported .NET FileOk event instead. A Winforms example:
private void SaveButton_Click(object sender, EventArgs e) {
string requiredDir = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments);
using (var dlg = new SaveFileDialog()) {
dlg.InitialDirectory = requiredDir;
dlg.FileOk += (s, cea) => {
string selectedDir = System.IO.Path.GetDirectoryName(dlg.FileName);
if (string.Compare(requiredDir, selectedDir, StringComparison.OrdinalIgnoreCase) != 0) {
string msg = string.Format("Sorry, you cannot save to this directory.\r\nPlease select '{0}' instead", requiredDir);
MessageBox.Show(msg, "Invalid folder selection");
cea.Cancel = true;
}
};
if (dlg.ShowDialog() == DialogResult.OK) {
// etc...
}
}
}

I don't this is going to work. Even if you disable the button they can type ..\ and click save and it will take them up one level. You can't exactly disable the file name text box and maintain the functionality of the dialog.
You'd be better off either using the FolderBrowserDialog and setting it's RootFolder property and asking the user to type the filename in or auto generating it.
If the folder you are wanting to restrict the users to isn't an Environment.SpecialFolder Then you'll need to do some work to make the call to SHBrowseForFolder Manually using ILCreateFromPath to get a PIDLIST_ABSOLUTE for your path to pass to the BROWSEINFO.pidlRoot
You can reflect FolderBrowserDialog.RunDialog to see how to make that call.

Since you want such custom behaviors instead of developing low level code (that is likely yo break in the next versions of windows) you can try to develop your file picker form.
Basically it is a simple treeview + list view. Microsoft has a walk-through .
It will take you half a day but once you have your custom form you can define all behaviors you need without tricks and limits.

Cannot add icon in shell extension with C#

I've found a very nice tutorial and i am trying to understand something that is not in this tutorial (because the tut itself works fine)
http://www.codeproject.com/Articles/9163/File-Rating-a-practical-example-of-shell-extension
When you look at applications like WinRar, TortoiseSVN, Antivirus-apps and many more, there is an icon next to the Shell Extension Item.
I would like to know how this is done. (Programmatically with C#)
Adding a separator works, adding a submenu works and click+action also works, but i'm struggling with the icon. This cannot be so hard. Can somebody help me?
And please don't say that Microsoft doesn't longer support this in .NET 4.0, because it is not guaranteed and therefore they don't supply samplecode. If all those other apps can do it, then it is possible.
Please supply me some sample code, some tutorials or maybe even a working piece of code.

Please have a look at the following article, it uses .NET 4.0 it to create Windows Shell Extensions using the SharpShell nuget package.
NET Shell Extensions - Shell Context Menus
Using this library, you can set the image directly while creating the contextmenustrip as shown below
protected override ContextMenuStrip CreateMenu()
{
// Create the menu strip.
var menu = new ContextMenuStrip();
// Create a 'count lines' item.
var itemCountLines = new ToolStripMenuItem
{
Text = "Count Lines...",
Image = Properties.Resources.CountLines
};
// When we click, we'll count the lines.
itemCountLines.Click += (sender, args) => CountLines();
// Add the item to the context menu.
menu.Items.Add(itemCountLines);
// Return the menu.
return menu;
}

You only have to add to the following registry key: HKEY_LOCAL_MACHINE\SOFTWARE\Classes*\shellex\ContextMenuHandlers
and here is the code:
string TimeStamp = DateTime.Now.ToString("dd-MM-yyyy");
string key = "HKEY_LOCAL_MACHINE\\SOFTWARE\\Classes\\*\\shellex\\ContextMenuHandlers\\Winrar";
string valueName = "MyWinrar";
Microsoft.Win32.Registry.SetValue(key, valueName, HERE WHAT YOU WANT TO START, Microsoft.Win32.RegistryValueKind.String);
i hope it works for you!

All the apps you listed use COM and unmanaged code to create overlay icon handlers. There is even a special project TortoiseOverlays that provides a common library for drawing icons for TortoiceCSV, TortoiseSVN and TortoiseGIT. You can take a look at it's source code to find out how it is done. If you want to draw similar icons, you should probably just reuse it.
Using .Net for this type of extensions is not recommended, because when multiple extensions, built against different .Net versions would attempt to load in explorer process, they will crash the explorer.

Playing Audio in .Net / C#

I'm an experienced MFC programmer of many years, who for the more recent years has been developing commercial apps in Objective C for Mac and iOS - I'm trying to get up to speed with .Net and C# (as I'm soon going to be required to convert one of my commercial apps from Mac to PC).
I've now worked my way through a couple of books and as an exercise to get more familiar with .Net (and C#) I've decided to have a go at converting one of my none commercial apps to .Net as a learning exercise and all is going well (interface is working, data structures all good) but I need to be able to play audio.
My Mac app generates audio from a series of mathematical formula - imagine a wave generator - not quite the same but similar. On the Mac I generate the audio as 16 bit signed raw audio, use Core Audio to setup audio output routing and then get a callback whenever a new buffer of audio is required for the audio routing (so I can generate the audio on the fly).
I need to do the same on the PC. Unfortunately I find MSDN documentation to be a case of "Can't see the wood for the trees" as there is such a vast amount of documentation. I can find classes that will let me load and play mp3/wav etc files, but I need to generate the audio realtime. Can anyone point me in the right direction to find something that will allow me to fill buffers on the fly as it plays them?
Thx

I have used this sample in several projects with good results. It is basically a .Net wrapper for Windows Waveform Audio API using P/Invoke.
Other choices:
NAudio
Sound Player class from .Net framework

I have created a class that can play audio given Stream derivate as an input. So if you are able to pack your sound-generator into the Stream compatible interface, it could be suitable for you.
How I did it - I used unmanaged waveOut* methods from old Windows multimedia API, and handled the playback from there.
Other options - that I am aware of - use waveOut directly, from this: http://windowsmedianet.sourceforge.net/ or write your own DirectShow source filter, but that might be too complicated, since it has to be written in c++.
If you are interested in giving my component a try, I can make it available to you at no charge, since I need it beta tested (I only used it in several of my projects).
EDIT:
Since there are 6 upvotes to the question, I am offering my component free of charge (if you find useful) here: http://dl.dropbox.com/u/10020780/SimpleAudioPlayer.zip
Maybe you can reflect on it :)

I use Audiere to accomplish this and find it works very well.
It's a C++ lib really, but there are a set of bindings available for C#.
For more info, see the question I asked.

You should have a look at FMOD which allows this kind of operation and much more. It is also cross platform which can be interested if you are also working on a mac.

Alvas.Audio has 3 audio players: Player
player.FileName = "123.mp3";
player.Play();
PlayerEx
public static void TestPlayerEx()
{
PlayerEx plex = new PlayerEx();
plex.Done += new PlayerEx.DoneEventHandler(plex_Done);
Mp3Reader mr = new Mp3Reader(File.OpenRead("in.mp3"));
IntPtr format = mr.ReadFormat();
byte[] data = mr.ReadData();
mr.Close();
plex.OpenPlayer(format);
plex.AddData(data);
plex.StartPlay();
}
static void plex_Done(object sender, DoneEventArgs e)
{
if (e.IsEndPlaying)
{
((PlayerEx)sender).ClosePlayer();
}
}
and RecordPlayer
public static void TestRecordPlayer()
{
RecordPlayer rp = new RecordPlayer();
rp.PropertyChanged += new PropertyChangedEventHandler(rp_PropertyChanged);
rp.Open(new Mp3Reader(File.OpenRead("in.mp3")));
rp.Play();
}
static void rp_PropertyChanged(object sender, PropertyChangedEventArgs e)
{
switch (e.PropertyName)
{
case RecordPlayer.StateProperty:
RecordPlayer rp = ((RecordPlayer)sender);
if (rp.State == DeviceState.Stopped)
{
rp.Close();
}
break;
}
}

How do I get latest clearcase label programmatically from C#?

I am trying to put version information to my C# GUI framework retrieved from the latest ClearCase label. This was originally done from Visual Soursafe as below.
vssDB = new VSSDatabaseClass();
vssDB.Open( databaseName, "vssadmin", "vssadmin" );
VSSItem item = vssDB.get_VSSItem( #"$\BuildDCP.bat", false );
foreach(VSSVersion vssVersion in item.get_Versions(0))
{
// Pull the first non-blank label and use that
if ( vssVersion.Label != "" )
{
labelID = vssVersion.Label.ToString();
break;
}
}
I am trying to do something similar using ClearCase since we changed our source code control from VSS to CC. Any help would be greatly appreciated.
Thanks!

I believe this could be better achieved through a script, which would be called from your C# program.
But you may be able to directly call some COM objects, through the CAL interface provided with ClearCase.
The documentation for the interface can be accessed through ClearCase help (Start>Programs>Rational ClearCase>ClearCase Help), where there's an entry for "ClearCase Automation Library (CAL)". An alternate path is to look in the ClearCase/bin directory for "cc_cal.chm".
In VB, with CAL API, that would give something like:
Dim CC As New ClearCase.Application
Dim labelID As String
Set aVersion = CC.Version("[Path-To]\BuildDCP.bat");
Set someLabels = Ver.Labels;
If (someLabels.Count > 0) Then
' the first label listed is the most recently applied
labelID = someLabels.Item(1).Type.Name
EndIf

I really wish that the COM interfaces had better documentation, or were more obvious. Or that the code to ClearCase Explorer or Project Explorer were open source.
I've done a few cool things, but I pretty much started by adding COM references to my C# project, and then started screwing around with the interfaces I found.
Good luck!