I'm working om project base on WPF .net 4 with Prism 4.0,
after I upgrade my machine from windows 7 to windows 8,
the project crash when reach the point of active view
object view = s.GetView(viewName);
if (view != null)
{
theRegion = (Region)s;
s.Activate(view);
}
The exception occur in the line s.Activate(view)
the exception details is"Value cannot be null.Parameter name: view"
This is strange because I check that the view isn't null.
on windows 7 it's working
any advice ?
Thanks
Yair
Hmmmm, that seems like a threading issue to me. Is there another piece of code that could be potentially running in parallel and also getting the view, and modifying it between the time the if statement and your Activate method is called?
If so, the double-check locking pattern would fix your problem.
if (view != null)
{
lock (myLock) // myLock is just a static object
{
if (view != null)
{
theRegion = (Region)s;
s.Activate(view);
}
}
}
Of course, you would also need to lock myLock in other places where you are modifying your view.
Related
I have a very, very large and complex Visual FoxPro 9 application. I'd like to rewrite portions of this application in WPF with the ultimate goal of completing cutting over a couple of years from now. I've spent a considerable amount of time searching google and stackoverflow for an end to end "hello world" type sample of how to implement this with COM interop. Found bits and pieces but nothing complete that shows both the FoxPro side and the WPF side.
My gut tells me I'm likely to run into issues with XAML resources, third party controls, or other normal functionalities of a WPF app if I try to run it via COM Interop.
So, two questions. Can anyone point me to an small end to end sample that either launches WPF windows from FoxPro or lets me drop WPF user controls on a FoxPro form? Or am I right with my concerns of potential interop issues and should avoid this altogether? If so, is there a recommended way for these two executables to communicate with each other?
I have absolutely no idea whether you can run wpf inside visual FoxPro. I would guess you'd have to write it as an activex.
I recently did some work extending a MS Access app.
My wpf app is completely separate and runs alongside the ms access app.
I communicated between the two using MS Message Queue - which is a com component.
Maybe this sort of approach could work for you.
When I wanted to show a screen in wpf from access I added a piece of xml to the local message queue.
The wpf app listens for these messages, casts them to objects which tells it which screen to show and gives it any parameters.
MS Access subscribes to the received message event on the message queue and that way it can tell when the wpf window closes and the user is done.
This was intended to use the strangler pattern to gradually replace functionality in the old access app.
Here's some code for the queuelistener that drives everything. The various pop classes are deserialised from the message and I build that as a string in access.
internal class QueueListener
{
public const string qFromMadge = #".\private$\XXXXQ";
public static string qToMadge = #".\private$\XXXXReturnQ";
private MessageQueue mq;
internal QueueListener()
{
try
{
SystemEvents.SessionSwitch += SystemEvents_SessionSwitch;
SubscribeHandler();
var mqSend = setUpQueue(qToMadge);
mqSend.Close();
}
catch (Exception ex)
{
MessageBox.Show(ex.InnerException.Message);
}
}
private MessageQueue setUpQueue(string qName)
{
MessageQueue q;
if (MessageQueue.Exists(qName))
{
q = new MessageQueue(qName);
}
else
{
q = MessageQueue.Create(qName);
}
q.ResetPermissions();
q.SetPermissions("Everyone", MessageQueueAccessRights.FullControl, AccessControlEntryType.Set);
q.Purge();
return q;
}
private void ReceiveMsgCompleted(Object source, ReceiveCompletedEventArgs asyncResult)
{
MessageQueue mq = (MessageQueue)source;
Message m = mq.EndReceive(asyncResult.AsyncResult);
m.Formatter = new XmlMessageFormatter(new[] { "XXXX.Popaaaa, XXXX"
, "XXXX.Popbbbb, XXXXX"
, "XXXX.Popcccc, XXXX"
, "XXXX.Popdddd, XXXX"
});
((BasePopView) m.Body).Pop();
mq.BeginReceive();
}
public void UnsubscribeHandler()
{
if (mq == null)
{
return;
}
mq.Close();
mq.ReceiveCompleted -= new ReceiveCompletedEventHandler(ReceiveMsgCompleted);
mq = null;
}
public void SubscribeHandler()
{
if(mq != null)
{
return;
}
mq = setUpQueue(qFromMadge);
mq.ReceiveCompleted += ReceiveMsgCompleted;
mq.BeginReceive();
}
How do I use the word editor in a WPF application? Is it possible using windows forms hosting in WPF only? Is there another way to accomplish that?
I found AvalonEdit but it does not have features that I need. So using this way, my problem may not be solved.
Also there is some stuffs out there to host a windows forms control in WPF, but it could not be my answer.
I want to understand that is there a way to use word editor in a native way in a wpf app?
Will all APIs be available in that solution?
Thanks in advance.
You can host MS Word (2007/2010 and probably other versions) from within a WebBrowser control, this works in WinForms and should work in WPF too. A .NET API is provided for automating Word, documented here. The required interop assemblies ship with Office 2010, so deployment is a lot simpler than previous Office versions.
See this Microsoft Support article for more details on hosting Word within a WebBrowser control. The Screenshot below shows Word embedded within a host Winforms application.
Note that this only works reliably for a single hosted instance of Word, so you can't show 2 Word documents side by side in the same application. Also, the Ribbon can sometimes go missing - but Word hasn't ever caused the application to crash.
Administrative rights are required to make the required registry updates as there are potential security issues. One easy method to make the registry updates is to write a script, but the following (revised/untested) code shows how this can be done in c# for Word, Excel and PowerPoint:
using System.Security.AccessControl;
private Dictionary<string,uint> OfficeBrowserRegKeys()
{
string[] officeRegKeyArray = new string[]
{
#"SOFTWARE\Classes\Word.Document.12",
#"SOFTWARE\Classes\Word.DocumentMacroEnabled.12",
#"SOFTWARE\Classes\Excel.Sheet.12",
#"SOFTWARE\Classes\Excel.SheetMacroEnabled.12",
#"SOFTWARE\Classes\Excel.SheetBinaryMacroEnabled.12",
#"SOFTWARE\Classes\PowerPoint.Show.12",
#"SOFTWARE\Classes\PowerPoint.ShowMacroEnabled.12",
#"SOFTWARE\Classes\PowerPoint.SlideShow.12",
#"SOFTWARE\Classes\PowerPoint.SlideShowMacroEnabled.12"
};
Dictionary<string,uint> officeRegKeys = new Dictionary<string, uint>();
uint wrdVal = 0x80000024;
uint excelVal = 0x80000A00;
uint powerPtVal = 0x800000A0;
foreach(string keyName in officeRegKeyArray)
{
if (keyName.Contains("Word"))
{
officeRegKeys.Add(keyName, wrdVal);
}
else if (keyName.Contains("Excel"))
{
officeRegKeys.Add(keyName, excelVal);
}
else
{
officeRegKeys.Add(keyName, powerPtVal);
}
}
return officeRegKeys;
}
private void setNewOfficeKeys()
{
uint editFlag = 0x00010000;
Dictionary<string,uint> officeRegKeys = OfficeBrowserRegKeys();
foreach (KeyValuePair<string, uint> kvp in officeRegKeys)
{
try
{
RegistryKey rKey = Registry.LocalMachine.OpenSubKey(kvp.Key,
RegistryKeyPermissionCheck.ReadWriteSubTree,
System.Security.AccessControl.RegistryRights.SetValue);
rKey.SetValue("BrowserFlags", unchecked((int)kvp.Value),
RegistryValueKind.DWord);
rKey.SetValue("EditFlags", unchecked((int)editFlag),
RegistryValueKind.DWord);
}
catch (Exception e) { string msg = e.Message; }
}
}
Well, Word proper isn't technically designed to be hosted by another app, whether it's WPF, WINFORMS or anything else.
You CAN use api tricks (like SetParent) to move the Main Word window into a WPF hosted window. I've done it before, but it's pretty tricky business and it's very easy to miss things that cause GPFs (both in Word and your app).
Is there any reason why it needs to be "Word in your app"? Why not write a little word addin and then launch Word from your app when necessary. then the Addin can communicate with your app, or your DB or whatever as necessary from within Word.
Users may find that to be a more usable approach in any case.
I have a Silverlight app that I hand off to the IT people you are supposed to publish it. This does not always happen correctly, they might forget, put in the wrong loc, or get the wrong version.
So I want to add something to the app itself to easily tell the latest version. This is for SL 3 and 4 so context menu probably not an option. I don't think the users would want a splash screen so that also probably not a choice.
Has anyone done this? Is there a clean, unobtrusive way of doing this?
If you have done this do you just use the assembly version or do use some custom value?
thanks
Here is code to check the assembly version of a running application:
string GetAssemblyVersion()
{
var assemblyName = new AssemblyName(Application.Current.GetType().Assembly.FullName);
if (assemblyName == null)
{
return string.Empty;
}
Version v = assemblyName.Version;
if (v == null)
{
return string.Empty;
}
return v.ToString();
}
Is there any possibility to programatically close Silverlight application on Windows Phone 7?
If you write an XNA Game, you will have access to an explicit Exit() method. If you are writing traditional Silverlight project, then NO, there is no way to programatically close your app. See also Peter Torr's Blog entry on Exiting Silverlight Apps in Windows Phone 7. There he also mentions the option of throwing an unhandled exception, which IMO is a terrible programing style.
An option you may try, is using the WP7 Navigation Service to programatically navigate back out of the application. Not sure if that would work though. Why do you need to Exit?
You can always call an exit by doing this at your landing page use this code on click of your application back button:
if (NavigationService.CanGoBack)
{
while (NavigationService.RemoveBackEntry() != null)
{
NavigationService.RemoveBackEntry();
}
}
This will remove back entries from the stack, and you will press a back button it will close the application without any exception.
Short answer for Silverlight is No.
You should not provide a way to close the applicaiton. Closing the applicaiton should be the users choice and implemented by using the back button the appropriate number of times. This is also a marketplace requirement.
That said, a silverlight application will close if there is an unhandled exception. I have seen a few people try and create programmatic closing by throwing a custom error which is explicitly ignored in error handling. This can work but there is still the marketplace issue.
XNA applications can explictly call Exit().
Some good info here already. Adding to this..
The platform is fully capable of managing closure of apps. The more apps don't provide an exit, the quicker users will become accustomed to not thinking about app house keeping, and let the platform manage it.
The user will just navigate their device using start, back, etc.
If the user wants out of the current app to go do something else quickly - easy - they just hit start.
.Exit(), whilst available for xna, really isn't required anymore either. There was a cert requirement during CTP that games had to provide an exit button. This is now gone.
Non game apps never had the need to implement this.
The more this topic's discussed (and it really has been given a good run around the block), the more the indicators to me suggest there is no need to code an exit.
Update: For those thinking of an unhandled exception as a suitable way of closing an app intentionally or letting the app close due to subpar operating conditions, I would recommend reviewing the comments concerning Application Certification Requirements in this answer. Is there a way to programmatically quit my App? (Windows Phone 7)
Here is another solution.
If you have an error page that i.e. displays error to the end user you can use the
protected override void OnBackKeyPress(System.ComponentModel.CancelEventArgs e)
{
base.OnBackKeyPress(e);
e.Cancel = true;
}
And you can instruct user to press start button to exit application.
Add a reference to Microsoft.Xna.Framework.Game, then call:
new Microsoft.Xna.Framework.Game().Exit();
private void PhoneApplicationPage_BackKeyPress(object sender, System.ComponentModel.CancelEventArgs e)
{
while (NavigationService.CanGoBack)
NavigationService.RemoveBackEntry();
}
That works for me fine.
You can close the app using this statement
Application.Current.Terminate();
This worked perfectly on Windows phone 7
System.Reflection.Assembly asmb = System.Reflection.Assembly.Load("Microsoft.Xna.Framework, Version=4.0.0.0, Culture=neutral, PublicKeyToken=842cf8be1de50553");
asmb = System.Reflection.Assembly.Load("Microsoft.Xna.Framework.Game, Version=4.0.0.0, Culture=neutral, PublicKeyToken=842cf8be1de50553");
Type type = asmb.GetType("Microsoft.Xna.Framework.Game");
object obj = type.GetConstructor(new Type[] { }).Invoke(new object[] { });
type.GetMethod("Exit").Invoke(obj, new object[] { });
Link - source
My 2 pence worth, reasons for an exit
1) there is no interent connection the first time it is run and it needs to create an account on a web service somewhere to run.
2) You need to force an upgrade for the user, again when tied to a web service, you may discover a bug in your app, or have web service changes that mean the user needs to be forced to upgrade, at that point you will want to inform the user that they must upgrade and then exit the app.
Currently in my app I am forced to take the user to a form that says "they" must exit, and if they click back they are again forced back to this page. not very nice.
In Silverlight, I throw an un-handled exception when I have to exit the application. I know that this isn't the graceful method to handle this but it is still the most convenient and easiest solution.
I know that according to the guidelines there shouldn't be any un-handled exceptions in the code but I write why I am explicitly throwing an un-handled exception in the Exception Request document at the time of submission.
Till now this method has always worked and never failed me.
Easiest way to do this is to add a reference to Microsoft.Xna.Framework.Game, then add
using Microsoft.Xna.Framework.GamerServices; before namespace. Then we have a button in our Example.xaml with Click="quit_button". In out Example.xaml.cs we put this code inside our page-class:
private void quit_Click(object sender, EventArgs e)
{
new Microsoft.Xna.Framework.Game().Exit();
//This will close our app
}
var buttonInfo = MessageBox.Show("Are you sure you want to exit?", "Exit", MessageBoxButton.OKCancel);
if (buttonInfo == MessageBoxResult.OK)
{
if (NavigationService.CanGoBack)
{
while (NavigationService.RemoveBackEntry() != null)
{
//
}
}
e.Cancel = false;
}
else
{
//Stop page from navigating
e.Cancel = true;
}
Navigate to App.xaml.cs in your solution explorer and
add a static method to the App class
public static void Exit()
{
App.Current.Terminate();
}
so that you can call it anywhere from your application , as below
App.Exit();
I am developing a WPF app that contains a webbrowser control that loads a silverlight application. I would like to be able to launch the app from visual studio (F5) and have the debugger attach to the silverlight code. However, I've not had any luck with this.
The best I can currently do is to launch the app without attaching, then once it is up and running, attach to the process manually with silverlight as the specified type of code to debug, and this works. (When I cause the web browser control to load the silverlight app, it will hit breakpoints in my silverlight code). I've written some macros to automate this launching/attaching somewhat, but it still isn't the best.
I've tried specifying the WPF app as the external program to run when launching/debugging the silverlight app, but Visual Studio attaches to the process wanting to debug the managed .NET code.
Any ideas? Ideally, I would really like to attach to the process and debug both the managed .NET and the silverlight code, but I don't think this is possible. I'd really like to automatically be attached to the silverlight code at launch so that I can easily debug all issues with the silverlight app, including those that occur on load.
Thanks for your ideas Brandorf and fatty. Brandorf's almost gets me to where I wanted to go, but does require that my SL app be capable of running on its own. I really want to have only the one app, which is both wpf and silverlight, with the SL side being debugged.
A long time after I asked this question (I forgot I had asked it here), I actually pieced together a solution that I'm really happy with. I use visual studio automation within the WPF/.NET side of my app, to find all running instances of visual studio, figure out which one produced my exe (since it typically sits in a folder below the vcproj/sln folder), and then use visual studio automation to have that VS attach to the app, debugging silverlight code. After this is done, I then load my silverlight content.
It works really well. You end up with an app that goes and finds a debugger to attach to itself every time it runs (so you probably want this code only in a debug build, or somehow able to be turned off). So you just launch the app with ctrl-F5 (launch without debugging) from visual studio whenever you want to debug the silverlight side.
Here's my code:
#if DEBUG
using System;
using System.Collections.Generic;
using System.Collections;
using System.Runtime.InteropServices;
using System.IO;
namespace Launcher
{
//The core methods in this class to find all running instances of VS are
//taken/inspired from
//http://www.codeproject.com/KB/cs/automatingvisualstudio.aspx
class DebuggingAutomation
{
[DllImport("ole32.dll")]
private static extern int GetRunningObjectTable(int reserved,
out UCOMIRunningObjectTable prot);
[DllImport("ole32.dll")]
private static extern int CreateBindCtx(int reserved,
out UCOMIBindCtx ppbc);
///<summary>
///Get a snapshot of the running object table (ROT).
///</summary>
///<returns>
///A hashtable mapping the name of the object
///in the ROT to the corresponding object
///</returns>
private static Hashtable GetRunningObjectTable()
{
Hashtable result = new Hashtable();
int numFetched;
UCOMIRunningObjectTable runningObjectTable;
UCOMIEnumMoniker monikerEnumerator;
UCOMIMoniker[] monikers = new UCOMIMoniker[1];
GetRunningObjectTable(0, out runningObjectTable);
runningObjectTable.EnumRunning(out monikerEnumerator);
monikerEnumerator.Reset();
while (monikerEnumerator.Next(1, monikers, out numFetched) == 0)
{
UCOMIBindCtx ctx;
CreateBindCtx(0, out ctx);
string runningObjectName;
monikers[0].GetDisplayName(ctx, null, out runningObjectName);
object runningObjectVal;
runningObjectTable.GetObject(monikers[0], out runningObjectVal);
result[runningObjectName] = runningObjectVal;
}
return result;
}
/// <summary>
/// Get a table of the currently running instances of the Visual Studio .NET IDE.
/// </summary>
/// <param name="openSolutionsOnly">
/// Only return instances that have opened a solution
/// </param>
/// <returns>
/// A list of the ides (as DTE objects) present in
/// in the running object table to the corresponding DTE object
/// </returns>
private static List<EnvDTE.DTE> GetIDEInstances(bool openSolutionsOnly)
{
var runningIDEInstances = new List<EnvDTE.DTE>();
Hashtable runningObjects = GetRunningObjectTable();
IDictionaryEnumerator rotEnumerator = runningObjects.GetEnumerator();
while (rotEnumerator.MoveNext())
{
string candidateName = (string)rotEnumerator.Key;
if (!candidateName.StartsWith("!VisualStudio.DTE"))
continue;
EnvDTE.DTE ide = rotEnumerator.Value as EnvDTE.DTE;
if (ide == null)
continue;
if (openSolutionsOnly)
{
try
{
string solutionFile = ide.Solution.FullName;
if (!String.IsNullOrEmpty(solutionFile))
{
runningIDEInstances.Add(ide);
}
}
catch { }
}
else
{
runningIDEInstances.Add(ide);
}
}
return runningIDEInstances;
}
internal static void AttachDebuggerIfPossible()
{
if (System.Diagnostics.Debugger.IsAttached)
{
//Probably debugging host (Desktop .NET side), so don't try to attach to silverlight side
return;
}
var ides = GetIDEInstances(true);
var fullPathToAssembly = System.Reflection.Assembly.GetExecutingAssembly().Location;
var potentials = new List<EnvDTE.DTE>();
foreach (var ide in ides)
{
var solutionPath = ide.Solution.FullName;
var topLevelSolutionDir = Path.GetDirectoryName(solutionPath);
var assemblyName = fullPathToAssembly;
if (assemblyName.StartsWith(topLevelSolutionDir, StringComparison.OrdinalIgnoreCase))
{
potentials.Add(ide);
}
}
EnvDTE.DTE chosenIde = null;
//If you have multiple ides open that can match your exe, you can come up with a scheme to pick a particular one
//(eg, put a file like solution.sln.pickme next to the solution whose ide you want to debug). If this is not a
//concern, just pick the first match.
if (potentials.Count > 0)
{
chosenIde = potentials[0];
}
var dbg = chosenIde != null ? (EnvDTE80.Debugger2)chosenIde.Debugger : null;
if (dbg != null)
{
var trans = dbg.Transports.Item("Default");
var proc = (EnvDTE80.Process2)dbg.GetProcesses(trans, System.Environment.MachineName).Item(Path.GetFileName(fullPathToAssembly));
var engines = new EnvDTE80.Engine[1];
engines[0] = trans.Engines.Item("Silverlight");
proc.Attach2(engines);
}
}
}
}
#endif
It's a bit of a shot in the dark, but assuming your silverlight app is capable of running on its own, you can, under your solution settings, set visual studio to start both apps together, and you should be attached to both of them.
If you can't add the Silverlight project to your solution (which will start debugging automatically), you might be able to make use of this tip. It will load both projects at the same time
http://saraford.net/2008/07/28/did-you-know-you-can-start-debugging-multiple-projects-268/