I've got a WebBrowser control on my page. To fire some javascript on a page displayed in the browser control. and when i try to save my web page i got this error
String strHtml = _browser.Document.Body.OuterText;
File.WriteAllText("C:\saveme.html", strHtml);
and this line _browser.Document.Body.OuterText throws the exception
Exception:: Specified cast is not valid.
at System.Windows.Forms.UnsafeNativeMethods.IHTMLDocument2.GetLocation()
at System.Windows.Forms.WebBrowser.get_Document()....
i had also used Invoke but does't work ,
is there any thing i missed out
Are you accessing the WebBrowser control from the UI thread? If not, try to access it from the UI thread or use Dispatcher.Invoke. See "Specified cast is not valid" error for more details.
Otherwise, the document probably has not completed loading yet. Wait until the DocumentCompleted event has fired to ensure the document has loaded, then access the property. See WebBrowser.Document.Body is always null for more information.
Related
I am facing an issue, while trying to start a phone call from my iOS app using:
UIApplication open(_:options: completionHandler:)
iOS shows an confirmation popup/alert before starting the call with two button Call & Cancel and CompletionHandler called with a Bool parameter having true/false based on button action in iOS 10.
But now in iOS11 the problem is that the completionHandler is being called automatically before tapping on "Cancel" or "Call" button of confirmation popup, always having true value.
Is this a bug in iOS11 or is there something that I am doing wrong?
There has been a behavior change in when the closure is called in iOS 11. I cant say if this behavior will be reverted or if this is a bug.
But one of the ways you can identify when the user interacted with the popup is by adding a notification listener around UIApplicationDidBecomeActive in the completion closure of openURL(). To identify whether the call was clicked or not you will need to create another custom notification and listener on the CTCallCenter. That was the best way through which I was able to identify it, there might be better solutions though :D
completionHandler will get a call if your given URL gets open success or failure, this has nothing to do with Cancel & Call buttons on Alert
see what Apple docs has to say about it HERE
completionHandler
The block to execute with the results. Provide a
value for this parameter if you want to be informed of the success or
failure of opening the URL. This block is executed asynchronously on
your app's main thread. The block has no return value and takes the
following parameter:
success
A Boolean indicating whether the URL was
opened successfully.
Within a Codename1 app, I'm getting a CrashReport: java.lang.NullPointException: Attempt to invoke virtual method 'void android.graphics.Point.setAntiAlias(boolean)' on a null object reference. This seems to occur after I invoke a "show()" on the main form of my application.
Note that the code runs fine in the simulator, but consistently gets this error prior to doing the "show()" on Android.
Interestingly, if I put a Dialog like this:
Dialog.show("Wait a sec", "Showing interrupt point", "OK", null);
before the .show(), and then click "OK", then everything runs well with no exceptions at all.
But a sleep(5000) instead of the Dialog does not help - still get the exception. So it at least seems like its not a race condition.
I have try-catches wrapped around all of the potentially offending code, and have NOT been able to isolate this. It always gets caught by the CrashReport, and only when running on the Android device.
Any ideas?
The symptoms to this one are pretty strange (i.e. workaround with a Dialog), and it would be interesting to have an explanation. However, since deprecated cn1 (Map) code has seemingly been implicated, I'm going to let this one go and replace this code with the latest Google native maps code. If it recurs, I will post another question then.
I create a window containing grids that send off ajax requests. Now, I immediatley close the window again before the grids are fully created and the ajax requests return.
I have two problems:
My components within a window are still "alive" after a window is destroyed
Chrome console lists them. Although my window has the autoDestroy: true the gridpanel and store are still existing after the window is closed. When closed, the destroy event is fired. Docs say, all components under the window should be destroyed.
Then my callbacks finally return and get executed but the window is destroyed
The problem is, that the callbacks try to reconfigure a grid that has no more store attached.
Error: Uncaught TypeError: Cannot call method 'getCount' of null Table.js:500 (/lib/extjs/src/view/Table.js
How can I stop the callbacks from processing if my window is destroyed?
Registering the events with mon so that they get removed when the listening object get destroyed. Alternatively you may:
remove them manually within the destroy() method
check within the callback for methods or properties that may not exist to skip them
Edit
There are some more things that you can do
check if the destroy() methods of the grids get called
abort all request by calling Ext.Ajax.abortAll() (before the window close)
abort just specific requestst by calling Ext.Ajax.abort(request) (before the window close)
I recommend to use option 2. because it should be the safest.
Edit 2
To take a look at all running request you need to look at the private requests property of Ext.data.Connection from which Ext.Ajax extend. requests is of type object and will contain a property (the request Id) for each request that is currently running.
I am trying to capture url parameters when page is loaded. I am using the beforePhase attribute inside the tag to call the backing bean method which handles the PhaseEvent. I am able to read the parameters but there seems to be some problem. The backing bean method is executed twice. First time I am getting all the url paramters but second time I am getting null.
This is the output in the console I get (The line "BeforePhase ONLOAD" is my SOP statement inside the method. As you can see the SOP is printed twice (below is the console output) -
* <_checkTimestamp> Apache Trinidad is running with time-stamp checking enabled. This should not be used in a production environment. See the org.apache.myfaces.trinidad.CHECK_FILE_MODIFICATION property in WEB-INF/web.xml
beforePhase ONLOAD
<_isBeanValidationAvailable> A Bean Validation provider is not present, therefore bean validation is disabled
beforePhase ONLOAD***
I have to use these url parameters to bind it to the view object and retrieve the data for the page. But if the method is called twice like it has been called here then the second will cause some database error or ultimately i will not see any records on screen.
Is there a way to handle this ?
I actually followed the Approach 1 example seen on this page - http://jneelmani.blogspot.com/2013/01/adf-how-to-call-method-on-page-load.html. In this example, he shows how to avoid beforePhase being called multiple times, I have done that but still the method is called twice.
Any suggestions here will be helpful.
Thanks.
Of course you know ADF supports a mechanism already for bookmarkable pages & URL parameters?
http://myadfnotebook.blogspot.pt/2010/11/bookmarking-with-adf.html
I am creating a xps document as below.
Assembly assembly = Assembly.GetExecutingAssembly();
//read embedded xpsDocument file
Stream helpStream = assembly.GetManifestResourceStream(resourceNameOfContext);
if (helpStream != null)
{
Package package = Package.Open(helpStream);
string inMemoryPackageName = "memorystream://" + topicName + ".xps";
Uri packageUri = new Uri(inMemoryPackageName);
//Add package to PackageStore
PackageStore.AddPackage(packageUri, package);
docXps = new XpsDocument(package, CompressionOption.Maximum, inMemoryPackageName);
}
return docXps;
When i am trying to get docXps.GetFixedDocumentSequence();
I am getting the above error. Can anyone help?
Thanks,
Your problem has nothing to do with the code surrounding the creation or use of the XPS document. It has everything to do with what thread you are running under.
You will receive the The calling thread must be STA, because many UI components require this error whenever any of the following are attempted on a MTA thread:
You construct any object derived from FrameworkElement (including Controls and Panels)
You construct any object derived from BitmapEffect
You construct any object derived from TextComposition
You construct any object derived from HwndSource
You access the current InputManager
You access the primary KeyboardDevice, StylusDevice, or TabletDevice
You attempt to change the focus on a FrameworkContentElement
You provide mouse, keyboard or IME input to any control that accepts text input
You make WPF content visible or update its layout
You manipulate the visual tree in such a way as to cause a re-evaluation for rendering
Several other changes, mostly having to do with display and input
For example, I received this error last year when I tried to deserialize some XAML that contained <Button> and other WPF objects from within a WCF service. The problem was simple to solve: I just switch to a STA thread to do the processing.
Obviously most work with XPS documents will trigger one or more of the above conditions. In your case I suspect that GetFixedDocumentSequence ends up using TextComposition or one of its subclasses.
No doubt the my solution of switching to a STA thread will also work for you, but first you need to figure out how your code that works with XpsDocuments is getting executed run from a MTA thread. Normally any code from from the GUI (eg a button press) is automatically run in a STA thread.
Is it possible that your code that manipulates XPS Documents may be being executed without a GUI? From a user-created thread? From a WCF service or a web service? From an ASPX page? Track that down and you'll probably find your solution.
If that doesn't work, let us know the details of the path through which GetFixedDocumentSequence is called, so we can diagnose it. The directly surrounding code isn't nearly as important as the call stack and how it is originally being invoked. If it is hard to explain you probably should add a call stack to prevent misunderstandings and help us diagnose the problem further, or tell you how to start a STA thread in your particular situation.
Is your code trying to access the xps doc from a background thread? If this is the case, you'll want to use the dispatcher. Info on that here.
If this doesn't help, could you post the code where you're actually calling GetFixedDocumentSequence()?