I am playing around with the WP7 SDK and the Prism for WP7 beta and have come across a problem I can't figure out (or even a workaround for).
First of all, I'm new into WPF/Silverlight/WP7 and Prism, so I could be overlooking something very obvious.
So I have a Shell page that has my region that is used to hold my content pages, and all of this is working great! Now my problem is that I have a settings control that will allow the users to edit the settings of the application (names, locations, etc). Now I can get this page to work with no problems by having a button on one of my controls that will transition the region manager to the control.
However, I would like to use the application bar on the phone to have the button, but I cannot for the life of me figure out how to get access to my model object from within the page that is opened by the Application bar click. I can only do a NavigationService.Navigate() to a settings page, but the PhoneApplicationPage objects in WP7 do not allow injection on the constructors (the constructors must be parameterless) so I cannot pass in the object instance in that way.
So my question is, how can I access (or pass) objects between pages or controls?
Thanks!
In the examples they use this technique to set the data context of a form after it is navigated to from another form:
NavigationService.Navigate(new Uri("/Page2.xaml", UriKind.Relative));
FrameworkElement root = Application.Current.RootVisual as FrameworkElement;
root.DataContext = some_object;
Related
I have a Prism 4.0 enabled WPF application that uses RequestNavigate extensively, and it is working well. I have a scenario where I would like to render part of my UI to an image and store it for later use from a Windows service. I already know how to use RenderTargetBitmap to generate the image, but whenever my code tries to call RequestNavigate, nothing happens. I am calling the bootstrapper, so I would expect that all of the types are loaded, but it just is not working. Can anyone tell me if this should even be possible? Is there anything inherent to RequestNavigate that prevents it from working when there is no UI present?
Individual steps:
First, I call Run on my MefBootstrapper. This loads up all of the assemblies into the AggregateCatalog.
Then, I use MEF CompositionContainer.GetExportedValue to create a WPF UserControl that has a single ContentControl that is assigned a RegionManager.RegionName. This always creates the initial UserControl just fine.
Finally, I call MefRegionManager.RequestNavigate with the region name on my UserControl and the path to another UserControl that I want it to load. This fails to load the UserControl that I am attempting to navigate to.
If these are the only steps that I follow, then the final UserControl fails to load whether I am running from a Windows Service or from within my WPF application. However, if I call SetRegionManager to explicitely add the region from my host UserControl before calling RequestNavigate, then the last UserControl will load properly, as long as the code is run from within the WPF application. If this same code is run from my Windows service, then it still does not load.
RequestNavigate is exactly that, a request to navigate to a loaded (but inactive) region. It won't do any loading itself. You need to separately manage the loading of views (including views within views).
If your nested user control is only over loaded within the parent, and you don't need to manage it at runtime, then you can use ViewDiscovery. You register all the views in advance, and then when the region is created, it looks for (and loads) all the nested views. If you need to manage the views at runtime, switch them in and out, etc, then you can use ViewInjection.
For ViewDiscovery, in the Initialize method of the ModuleInit class in your module, insert the following line:
_regionManager.RegisterViewWithRegion("RegionNameOfYourNestedControl",
() => this.container.Resolve<NestedUserControl>());
Then when your region is loaded, the NestedUserControl will automatically be loaded into your ContentControl (region).
For more detail on ViewDiscovery, ViewInjection and UI composition, have a read of the prism documentation
I'm new in Silverlight. A used the SilverLight Business Application template to create an application. I added a HypperlinkButton to the MainPain.xaml that pointed to a view, say ProductListView. Now I created a new view, say DataFormView, and I wanted the HyperlinkButton to point to that new view in order to test it, but when i run the application, it's the old view that's shown (ProductListView), though i have change the NavigateUri property to point to the new view.
I added a new HyperlinkButton to point to the new view, but it seems that it's the old main page that is shown (with one hyperlink button).
Can anyone help?
Thanks!
The easiest way to know navigation in silverlight, Just open new Silverlight Navigation Application project, where you have simple navigation is performed using navigation frame and Hyperlinkbutton.
This is likely a problem with the xap file getting cached. Try rebuilding the application. There are other ways to clear the browser cache as well:
http://www.codeproject.com/Articles/143414/Prevent-your-Silverlight-XAP-File-from-Caching-in
Making the Silverlight XAP file expire from browser cache programmatically
I am having a my problem is I can not redirect my page in silverlight like most of people who are not familiar with this technology .
I design a login page first and if password is correct I want it to direct to MainPage.xaml
as you can see I tried methods which are commented already it did not work . I searched in this web page there are some posts about this problem but I could not solve please help me .
when i try that one;
Uri target = new Uri("MainPage",UriKind.Relative);
NavigationService.Navigate(target);
error message : Object reference not set to an instance of an object.
actually we found a solution with my friend ;
instead of directing a web page , when code goes into if block we are changing the content of page with {this.Content = new MainPage() ; } method and it is working .But System.Windows.Browser.HtmlPage.Window.Navigate(target) this one is directing us same login page or pages like www.---.com outside normal html pages .
Normally you need to use the NavigationService to do this:
NavigationService.Navigate(new Uri("/MainPage", UriKind.Relative));
The NavigationService is a property on the Page object so it will be available in the Login code-behind.
However, after you mentioned that you've "already done this" I realized the issue. Silverlight Navigation uses a Frame control. This Frame control lives in MainPage.xaml for the default project. So you're not navigating inside the frame, but you want to change the entire screen to a different one and do so without the Navigation services built into Silverlight.
I'd suggest you either (a) have the Login run as a page inside of the Frame on MainPage (you can load or unload the links on the top based on if the user is authenticated) or (b) don't use the Navigation for the remainder of the application and use a framework like Caliburn.Micro to handle all the Navigation between views.
i m new developer to mobile apps and working on silverlight.
i want to knw how to pass value from textbox on one page to textbox on another page in mobile windows apps not in web apps using silverlight in c#.
So many options for this one:
Add variables to your app class
Global variable anywhere in the app (yuk)
Use a shared ViewModel if you are following the MVVM pattern
Store in App.Resource settings (these are easily bound to)
There is a shared app data store specifically for binding, but I can't remember what it is called or if it is in the mobile version (anybody?).
What are you doing with this value that is shared between to pages? The usage determines where/how it should be stored.
Taken from Exercise 1: Creating Windows Phone Applications with Microsoft Visual Studio 2010 Express for Windows Phone
Task 3: Step 9
// navigate
this.NavigationService.Navigate(new Uri("/PuzzlePage.xaml", UriKind.Relative));
Note:
The PhoneApplicationPage class provides methods and properties to navigate to pages through its NavigationService property. You can call the Navigate method of the NavigationService and pass the URI for the page as a parameter. You can also use the GoBack and GoForward methods to navigate backward or forward in the navigation history. The hardware back button also provides backward navigation within an application. The event handler shown above uses the NavigationService to go to the PuzzlePage.xaml page.
Task 4: Step 3
(RootVisual as Microsoft.Phone.Controls.PhoneApplicationFrame).Source =
new Uri("/ErrorPage.xaml", UriKind.Relative);
Note:
...
Whenever you set the Source property to a value that is different from the displayed content, the frame navigates to the new content.
...
What are the differences and similarities of both techniques?
Essentially, they both do the same thing.
NavigationService.Navigate is a native Silverlight navigation service to allow the asynchronous navigation from one xaml file to another (eliminating the need to load usercontrols) - there's an excellent little overview here.
The difference is that NavigationService has the ability to go backward and forward in a browser-esque fashion. Setting the Source property of the PhoneApplicationFrame does not.
Still early days and it's probably too soon to make an educated guess as to which you should use.
NavigationService has the advantage of being a Silverlight-native class, however PhoneApplicationFrame.Source is specific to WP.