WebBrowserControl uninitialized when coming back from sub screen - windows-phone-7

i have a page with a WebBrowserControl + some buttons at the bottom. When i click on of the buttons, a subpage is opened (NavigationService.Navigate(...)).
Now, when i'm on the sub page and close that page via NavigationService.GoBack() the WebBrowserControl is just white. Seems like it is completely uninitialized. Also checking WebBrowserControl.Sourcegives null.
Any ideas?

In a case like this you would want to make sure you are keeping track of objects in isolated storage or known as TombStoning on the WP7.
you would want to save page state onNavigatingFrom() and Load it onNavigationTo().
That should work. :)

Related

xcode two uitabbarcontrollers one page. auto-rotate issue

Summery:
I have a custom UITabBarAutoRotateController which returns YES from shouldAutorotateToInterfaceOrientation. This has no effect.
If I minimize and show the app again, the rotation issue goes away.
How do I refresh the screen so the user does not have to do this (so rotation works again)?
Details (setup graphically, so no code):
I have two UITabBarController in MainWindow.xib. I only want one to show at a time. So I am linking graphically rootViewController = tabBarController_name1. There is also tabBarController_name2.
I will also have an alert MessageBox for a user to choose what type of application they need, and it will choose a tab bar controller based on their request (per customer definition). This is commented out for now.
There is a bug with Rotation when two UITabBarControllers exist on the same xib. When I try to rotate the screen, it stays upward with wherever the main screen button (power button looking button) faces. HandleOrientationChange does not get called on the active custom ViewController being shown.
The reason I believe it's a bug is because if I hit the main screen button (minimizing the application), and click back on the application (brings it back to the foreground), rotation works perfectly!
Sorry for making you read all that mumbo :). My true question is, "Is there anyway I could refresh the main window or likewise UITabBarController's to get rotation working (without requiring the program be minimized and shown)"? A work-around, if you will?
p.s. I cannot use Storyboard for backwards compatibility reasons. The customer will be receiving this code/project. So I would like to keep this in one graphical page, rather than hiding/showing UITabBarItem's.
EDIT: two-uitabbarcontrollers-and-autorotation and uitabbarcontrollers-and-uinavigationcontrollers were both helpful, but did not address "why" this issue happens. "noob" here when it comes to xcode :)
Tab bar controller inside a navigation controller, or sharing a navigation root view is the answer. Do not use a TabBarViewController. Which, as a noob, I'm not quite sure why TabBarViewController exists (or at least isn't depreciated).
Dragging two TabBarViewControllers into the same page should result in a warning saying that you probably want to implement TabBarViewController by making a custom UIViewController and attaching a plain UITabBar to it.
Frustrating...but finally making progress :)

dojo Show/Hide One ContentPane While Another ContentPane Is Liquid

I've been struggling for weeks trying to crack this nut so I'm not sure if it's impossible, or if it's my lack of coding chops... or both. I'm not a programmer and I'm a newbie to Dojo Toolkit.
I have a site using the BorderContainer layout. I'm trying to create an effect where I can use a button to open and close a dropdown type box that will contain controls. I need this dropdown to be hidden on page load, and then open when you click the button.
My problem is that when I open the dropdown, it pushes the content pane below it off the bottom of the browser window. I need the lower ContentPane to stay fit within the remaining space of the browser window when the dropdown opens. Additionally, I want the dropdown to sit outside of the scrollable container for the content below it, which is why I have it set up to sit outside a nested BorderContainer below it.
I've created a simplified version of the code to demonstrate my challenge (see link below). If you load the page you can see the center ContentPane scrolls the content. But, if you then click on the button, a dropdown div expands above the content. Then when you scroll, you'll notice that you can't see the full pane because it's in no-man's-land below the bottom of the browser window. I assume that because the div is set to display:none on load, it's size is not accounted for on page load. Then, when you open it by pressing the button, it's size is additive and the pane below doesn't know how to resize or account for the new element.
I've tried using the visibility attribute, but that leaves a gap for the div when it's still closed. I've tinkered with some code that controls the height that shows promise, but each of my dropdown boxes will be different sizes so I'd prefer that the height be set to "auto" rather than a specified pixel size.
Does anyone have any idea how I can accomplish this so that the lower pane will fit in the space without pushing off the screen?
Here's a sample of the page:
http://equium.com/scaffold.html
(I had some problems trying to insert the full HTML page here as a code sample so if that's a preferable way to handle it, and someone can let me know the best way to embed all of that code, I'd appreciate it.)
Thanks is advance, I'd really apprecaite anyone's feedback.
You might want to take a look at dojox.layout.ExpandoPane (though be warned I think it has only worked properly for top and left regions for a while).
Also, I'd suggest simplifying/altering your layout a bit. See example here:
http://jsfiddle.net/taFzv/
(It'd probably need some tweaking to get exactly what you want.)
The real issue you're having is probably that the BorderContainer has no idea that parts of the view resized. ExpandoPane takes care of that by telling the BorderContainer to re-layout after its animation completes.
It works under IE8.0. When dropdown box open, just keep pressing mouse from page and drag to bottom, you could see the content was pushed to out of page. It looks the browser could not detect it and could not add it to "scroll bar" account.
I would suggest taking out all BorderContainers except your top level one, the one with mainPage as the id.
Place your {stuff here} div into the mainPage BorderContainer, after the ContentPane with the Close/Open button. Make sure you make it dojotype dijit.layout.ContentPane, set up layoutpriority, and set region to top. Set the height to 0/x when clicking the Open/Close button, instead of setting display.
Try your page again. If that doesn't fix it, you probably need, a call to layout, resize, or both to indicate to the BorderContainer that it needs to evaluate all its children and size the "center" pane properly. Something like dijit.byId("mainPage").layout(); Do this any time someone presses the Close/Open button, after you have changed the height of any BorderContainer children.
Maybe the dijit.form.DropDownButton would fit your needs. When click the button a tooltip is displayed that can be filled with any content you want. Just as you specified, the dropdown tooltip is only displayed when you click the button, and it doesn't mess with the underlying layout at all. The tooltip sits "on top" of the page.

How i Scroll web browser control in wp7

i want to swipe webbrowser Control which is on pivot item ,each pivot item
has a web control .i want to swipe with web browser control .
but i don't have any idea.but swiping is necessary in my project .is there any method to doing this if yes then please send me sample code for this ..
This is a bind if you have some different sections of HTML you want to display in a Pivot. If you are targetting WP7 Mango it might be possible for you to convert your HTML to RTF and then use a RichTextBox instead of a WebBrowser. However if your HTML is fairly complex, this probably isn't going to work for you.
Alternatively you could place your WebBrowser in a pivot item with a transparent Rectangle above it in the Z-order. Make sure that Rectangle swallows any gestures and doesn't pass them through to the WebBrowser control - that way you will be able to swipe left and right on the WebBrowser to get the pivot to move.
Next you can use the GestureService on this transparent rectangle to recognize vertical pans/swipes and taps to take you to a full page view of your WebBrowser content. In this full page view you would have a fully interactive WebBrowser control.
You have an issue with competing gestures. Try setting the WebBrowser control to IsHitTestVisible to false. This will mean that you'll be unable to manipulate or scroll the content of the WebBrowser control though.
shanu: if you still need it, check my recent answer at: WP7 Pivot control and a WebBrowser control
There's a bit of info on how to "hack into" the webbrowser and what to do, to (almost) prevent it from stealing your swipes. If you are insane/masochistic enough to try that approach I described there, then in addition to that eventhandling and other configuration/detection, you will have to drive your pivot manually via relevant pivot.selectedindex++/-- on H-swipes detected with your handlers (or you can separate blocking and observing with gesture listener, that may sometimes result in the code being a bit cleaner). I also think you will have to be careful with the selectedindex near to the page ranges. I dont know how pivot behaves if you order it to go further than you page count, and I dont know either if it will animate correctly, if being on the last page you order it to go "wrap around" and go to page 0 via selectedindex=0. It may get "crazy" and rewind back instead of going forward in a circular fashion.. you will have to experiment with that

How to check if Image is loaded while coming back in Navigation stack

In my MainPage I have added many images, each of them is retrieved from server by making HttpWebRequest. Also there are some links on MainPage, clicking on those links takes the user to a new page.
The problem I am facing is before all the images are loaded in the MainPage itself, if I click on any of the links on the MainPage, a new page is created and shown and all the pending image requests are canceled. Now If I come back to MainPage by clicking on the back button, the unloaded images still remain unloaded.
I have no idea how to check whether the images have already been loaded or not, when I come back to MainPage in the navigation stack(If I am able to find out that some images are not loaded, I can request the server again for the unloaded images). I need a generic solution for this. Because parent child relationship in the MainPage content layout is dynamic, means I do not know the hierarchy of the Image control, Image control can be a child of a canvas which in turn added to the MainPage's Content grid or the image can be added in one of the sections of a panorama/pivot which in turn added to the MainPage's Content grid, etc,....
There is an event on the Image control related to that -> http://msdn.microsoft.com/en-us/library/system.windows.controls.image.imageopened(v=vs.95).aspx
As argh suggested use the ImageOpened event (and perhaps also ImageFailed) to track whether the image has been loaded successfully. You could create a wrapper control around Image (can't inherit since it is sealed) to monitor the event and implement your own IsLoaded property.
You can use VisualTreeHelper.GetParent to traverse up through the tree and see whether the Image control is a descendant from MainPage for the second part of your problem.
This should work, however, I'm wondering why the images are not re-loaded when you press the back button. I don't think any of the suggested 'hacks' should be necessary. Are you using any custom logic for image loading etc.?
You can check Name of Image Temp . beacause in my project i use image temp show before image has load in server.
You can check the current name of the Image, if it is similar to the Temp Image name, then continue down they will not down
My code :
if(((BitmapImage)img.Source).UriSource.Equals("/NhomMua;component/Image/img_temp_sale.png"))
{
//code of you
}
I would suggest you have a look at the LowProfileImageLoader http://blogs.msdn.com/b/delay/archive/2010/09/02/keep-a-low-profile-lowprofileimageloader-helps-the-windows-phone-7-ui-thread-stay-responsive-by-loading-images-in-the-background.aspx) as a generic way to handle loading of images in an efficient manner. If you specifically need to be able to cancel and resume the loading of images you should able to modify that code to handle that pretty easily - although I'm not sure why you'd want to, remember its more efficient on the battery to download all the images in one hit than to stop and start.

Which is better, some grids collapsed or some user controls?

I'm developing a Windows Phone 7 application that uses some Transient content.
To avoid to go back to that transient content I've decided to use a phew page with several grids on the same page.
When I have to show another "page" I set to collapsed current grid and then I set to visible desired grid.
I know this can be done using user control, but I'm not sure if using user controls can be slowest that using Grids. Any advice?
And another question is if I use grids, how can I use page transitions?
Another option for when you want to show transient content is to use a Popup control. This won't appear in the navigation stack, so when a user goes back (<-) they won't see this content.
However, Popup content isnt GPU accelerated, so you only want to display simple content, no animations etc...
If you want page transitions etc... then i think your only option is to use Pages. That way you can do the transitions and the back button works as expected.
It doesn't matter if you do this via user controls or grids - what matters speed wise is the complexity of your layout.
A user control may be better if you are doing this on a number of pages so you don't repeat yourself.
One way to do page transitions is to do it with stack panels. Have the second "hidden" stack panel way off to the right so it is off screen then animate it in.

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