|
Ladies and Gentlemen,
i have had something rear its ugly head today and I frankly do NOT for the life of me understand how this can be. After spending a couple of hours PROVING to myself (I am not always easily convinced) that what I am see is real, I scoured the net to the best of my googling abilities and came up empty. So I lay this at your feet hoping someone here has an answer.
Naturally, I am on the customer site with a hard deadline and more than just my reputation at stake! I will spot you that I am NOT the most experienced Windows developer on this plant, but I have been around the block a few times.
Here is my story.
I have created a WPF application that is very much multi-threaded. In fact it is highly dependent on these threads. There are 5 main threads: 1) UI; 2) TCP/IP server; 3) GPIB client; 4) main application; and 5) the main application interface.
When the app starts, MainWindow runs as with most WPF type apps. In the constructor I create some little class to do this and that and I instantiated each of the objects for the 4 main threads (obviously I am in the UI thread). Once the constructor is done the app drops into the normal sort of WPF wait for something to happen kind of thing. Meanwhile my other threads are busy handling comms, reading files and a variety of other things. When a particular msg arrives via TCP/IP the MainWindow is notified and he throws up a Window being used as a dialog. nothing fancy, just var dlg = new myWindow(); dlg.ShowDialog();
Here is where it gets REALLY weird! Every thread in the app stops! Freezes. Goes out to lunch! Describe how you wish. But they freeze. When the dialog is dismissed everybody goes about their business like nothing happened. Of course the reeks havoc on comm threads.
Anybody and ANY ideas why this is happening?? And more to the point what the remedy is?
Oh, I create my background threads using:
Task.Factory.StartNew(() =>
{
_pxiHandler.MainLoop();
}, TaskCreationOptions.LongRunning);
TIA,
Doug
I am a Traveler
of both Time and Space
|
|
|
|
|
I suspect your background threads are running on a TaskScheduler which is tied to the Dispatcher of the UI thread. Try passing TaskScheduler.Default to the Task.Factory.StartNew method:
Task.Factory.StartNew(_pxiHandler.MainLoop,
CancellationToken.None,
TaskCreationOptions.LongRunning,
TaskScheduler.Default);
Obviously you'll need to make sure that any UI access or collection modification is posted to the UI thread.
"These people looked deep within my soul and assigned me a number based on the order in which I joined."
- Homer
|
|
|
|
|
Richard, thank you. Very much! An excellent suggestion! However after a sleepless night (anybody know why stuff like this always happens on site during acceptance testing?) a good friend this morning showed me error of my ways. You, see, the only problem was I have a wretched case of idiotitis. In my zeal to explore the nooks and crannies of this Windows world I made the decision that a nice clean way to allow objects to get information from other objects was exposé an event and delegate. Seemed reasonable to me at the time. Having spent most of my life in a world where objects on different threads have REAL boundaries I assumed that if some object from another thread registered a handler that naturally when that handler was invoked from thread 2 that the event would interrupt thread 1 it would process the event and thread 2 would go merrily on its way. Nope. Thread 2 runs the event handler. Well when the thread that is minding your comms is now suddenly executing code in MainWindow which consists of putting up a dialog guess who isn't watching his comms.
Error of my ways #2 has to do with where one starts threads, which is the point you are making. I was informed that launching critical long running tasks from the MainWindow code was not a very good idea. Suggestion was to move them to the App class and override OnStartup. Which I have now done. That does create several questions but I will save them for another day.
Error of my ways #3 was to foolishly mentally assign characteristics to objects in threads as I would to a process of lightweight thread in other operating systems. Not a good analogy.
Sorry for the length but somebody out there will make the same boo-boo someday.
Thank you again,
Doug
I am a Traveler
of both Time and Space
|
|
|
|
|
Hi All
Can Anyone Tell The Difference between MVC/MVC3 and MVC4
-- modified 5-Apr-13 7:17am.
|
|
|
|
|
You could have easily foudn this yourself just by typing "Whats new in MVC 4" into any search engine.
Like this...[^]
|
|
|
|
|
I have 3 richtextboxes I want to save all 3 in the same rtf file and load the file with the specific text in the apropriate richtextbox
How can you load specific part of the text file in a richtextbox then load another specific in another.
Like read the rtf file and when a certain string is found add the text below that in richtextbox1 and if another specific string is found stop adding to richtextbox1 and start adding to richtextbox2 and lastly when another specific string is found stop adding to richtextbox2 and start adding to richtextbox3
Thanks in advanced
|
|
|
|
|
Member 9706512 wrote: How can you load specific part of the text file in a richtextbox then load another specific in another.
Read all lines from the RTF-file. Split it into three parts at the markers (you do have markers in your document?) and put each part into a RichTextBox.
Where are you stuck in building this? Can you post your code?
Bastard Programmer from Hell 
If you can't read my code, try converting it here[^]
|
|
|
|
|
Hi,
I am using Entity Framework 4.5, I have to join 5 table entities and get result of Complex Type CT. This Complex Type contains other list of objects as its members.
For example: we have entities A, B, C, D and E, which are having any one column related to each other entities. There are 5 other Classes which are derived from the above entities. Like class A1 is using some columns of A and B1 is using few columns of B and C1, D1 and E1 are using some of the columns of C, D and E respectively.
The complex type CT is having list of A1, list of B1, list of C1, list of D1 and list of E1.
Now I want to join or include on Entity Framework entities and get the result as CT object but it contains lists of different objects.
Can anybody please help me in writing this complex join or include query whichever is better for the performance. Any help is great supportive any link or any code snippet etc.
Thanks in advance.
Thanks & Regards,
Abdul Aleem Mohammad
St Louis MO - USA
|
|
|
|
|
Hi,
My background is in MFC.
I have followed tutorials from Microsoft and W3Schools. It all seems to concentrate on getting the same page (albeit updated) sent back from the server. The difference is made by Get and Post.
I need a system, where one page begets the next, (depending on choices) where 'back' brings you back to the previous page.
Where or How do I get this!
Regards 
Bram van Kampen
|
|
|
|
|
It sounds like your looking for something like 'Server.Transfer()'. The page executing the incoming request will stop processing and pass control to a new page you specify like a method call.
|
|
|
|
|
I think you want the ASP.NET forum.
Use the best guess
|
|
|
|
|
Hi
For multiple employees (one or more), I have to generate report
--Report will be same for all employees
--Each page of report viewer will contain a single report for a single employe.
For example, for 10 employees ten report will be in ten pages of a single report viewer.
I am making report with RDLC
How i will do it??
Please help me
Thanks
modified 2-Apr-13 0:46am.
|
|
|
|
|
|
Sandeep, Thanks for your reply
But what i need is, you know report viewer has paging. So when i will click for next page it will show same report for 2nd employee.
In this way i want to show multiple employees information where each page contain same report for separate employee
|
|
|
|
|
Paging is for a report. You seek that page change changes report in viewer which is not how it works.
If you need that, put all employees in a single report with page break on every employee such that all start from new page. Thus, one report, one viewer and employees on each page.
|
|
|
|
|
how can i convert one language to another language typing in one text box it will show in next text box plz its show me the code..;)
|
|
|
|
|
That depends on what "languages" you're talking about. Are you talking about human written languages, or programming languages??
In either case, you'll have to send the input text to an on-line translator service (of your choice) and just ut the returned text into the other textbox.
No, I don't have example code.
|
|
|
|
|
Hi,
Have a look at this article:
Google Translator[^]
The quick red ProgramFOX jumps right over the Lazy<Dog>.
|
|
|
|
|
You will need a huge dictionary with grammar rules or more easily, a third party API that will do this translation for you.
|
|
|
|
|
Google translator has an API (but not free). If you can pay it can server your API call well:
https://developers.google.com/translate/v2/pricing
|
|
|
|
|
|
|
I have a customized WPF button control and I want to use this control with a WinForm application. I know how to use WPF user controls with WinForm using ElementHost. But I have no idea to use any single control (not a user control) with all its members with a WinForm application. Can you suggest me a good way to achieve this
|
|
|
|
|
Same way as a UserControl? The example on MSDN[^] uses a Button from WPF, so I assume it's not limited to UserControls.
Bastard Programmer from Hell
If you can't read my code, try converting it here[^]
|
|
|
|
|
Hello, hope you can help me on this
Am using a DevExpress Ribbon and I need it to be RightToLeft, any work around?
|
|
|
|
General 
News 
Suggestion 
Question 
Bug 
Answer 
Joke 
Praise 
Rant 
Admin 
Submit an article or tip
