Is it just me, or is it impossible to navigate to a page that does not have a .xaml head?
I am constructing a page entirely in code, and I want to navigate to it. I do not want a xaml page because this is a class library and also it is constructed based on data received. I know all about using .xaml to create the page with templates, binding, etc., but I want to avoid that.
When I call Frame.Navigate(typeof(CodePage)), I get nice AccessViolationException.
My page is simple, and so is the navigation. This is the code with a clean, new project
Navigation (button click):
Frame rootFrame = Window.Current.Content as Frame;
rootFrame.Navigate(typeof(CodePage));
Page:
public class CodePage : Page
{
public CodePage()
{
Content = new TextBlock
{
Text = "It works!",
};
}
I know about this issue: Navigate to a Page of another Class Library but, this is because ALL the pages are in the library, I just have 1 specific page in my library. Also, I have other pages in the "launcher" app.
Navigation only works with pages who have xaml part as well because when the page does InitializeComponent in its constructor it sets up the page for Navigation routes and NavigationCache etc.
Related
I have some controls on a page in a Xamarin.Forms app that DO NOT WORK when navigating back to the page. I can only "go back" to the page by navigating to the page outright (I'm using Prism to do this) and it works.
When transitioning to MAUI, I'm writing my own navigation service to replace Prism. Everything works, except navigation to replace the first page and clear the navigation stack. This is NOT App.MainPage.Navigation.PopToRootAsync() The page is the first page in the navigation stack. Attempting to replace App.MainPage with a new page does not work. Nothing happens if I do this.
Example navigation stack:
MainPage
Page1
Page2
Navigation stack after navigating to new root page:
MainPage (but new instance of page, not the original instance). Remainder of navigation stack has been cleared.
I'm not sure what I was doing wrong, but further testing shows that you can replace MainPage for Maui.
You CANNOT just assign a NavigationPage to MainPage. This will work for the navigation and any logic in associated viewmodel will work, but the UI will be blank.
If you just assign a ContentPage to MainPage, everything works great.
I have a master detail page as the root page for my application. As a detail page for that I have a tabbed page. In the tabbed page I have a content page and a navigation page containing one content page. In the master detail's OnNavigatedTo I'm retrieving some organisation data from the cloud and then I want to navigate to a manage organisation page which is the plain content page in the tabbed page.
Using NavigateAsync and a relative uri to the manage organisation page I find that the Tabbed Page OnNavigatedTo is hit twice and then I get an exception such as (simplified) below. I can also see Binding errors in my output showing that elements on my manage organisation page xaml tried to bind to the tabbed page view model.
I'm not sure if this is an issue with the view model auto wire change in 6.2 or if it's a deep linking issue or if I've done something wrong.
"Sequence contains no elements".
at System.Linq.Enumerable.Last[TSource] (IEnumerable`1 source) [0x00079]
at Xamarin.Forms.Platform.Android.AppCompat.NavigationPageRenderer.OnAttachedToWindow () [0x00011]
in C:\BuildAgent\work\aad494dc9bc9783\Xamarin.Forms.Platform.Android\AppCompat\NavigationPageRenderer.cs:189
Using XF 2.3.1.114, Prism.Forms 6.2, I'm not sure if other packages are relevant. If you think so I can include them.
Also interestingly, it works if I try navigate to the content page in the navigation page from the master detail i.e. "TabbedPage/NavigationPage/ContentPage".
Any ideas what the problem might be?
So first thing first, you don't have the proper XAML syntax for your TabbedPage. When defining the default page for a NavigationPage in XAML you must supply the page via the Arguments element:
<views:SimpleNavPage Title="Foo">
<x:Arguments>
<views:NestedContentPage />
</x:Arguments>
</views:SimpleNavPage>
You must also have the proper ctor in your navigation page:
public SimpleNavPage(Page root) : base (root)
{
InitializeComponent();
}
Now, I personally don't recommend navigating within the OnNavigatedTo unless you can absolutely guarantee that you will not be adding that page in another deep link, or navigation scenario. Imagine you start out with NavigateAsync("MainPage") and that has an OnNavigatedTo that does a deep link navigation operation. Now you decide to NavigateAsync("SomeOtherPage") in which it NavigateAsyc("AnotherPage/MainPage/SomeOtherPage/LastPage") from within it's OnNavigatedTo. Now, you will have created an issue because the MainPage.OnNavigatedTO will have kicked off another navigation operation while you are still navigating to the next "SomeOtherPage". You are asking for trouble.
I read around hundreds of Q/A & Blogs for the same, but not able to resolve the error I am getting. In my WPF application I need to navigate from a MainWindow.xaml to a Page Register.xaml. I have below code :
Register register = new Register();
MainWindow.Navigate(register);
Or
this.NavigationService.Navigate(new Uri("Register.xaml ", UriKind.Relative));
It is giving me error
'.MainWindow' does not contain a definition for 'Navigate'
Or
MainWindow' does not contain a definition for 'NavigationService'
To open a page in you need to have it in a frame.
A page can be hosted from Window, NavigationWindow, Frame, or from a browser. To be hosted, a page can be:
The direct child of a Window, NavigationWindow, or Frame element in
XAML.
Instantiated and set as the value of the Content property of Window, NavigationWindow, and Frame.
Set as the uniform resource identifier (URI) source of the Source property of either NavigationWindow or Frame.
If you want to have it in your MainWindow you can do the following.
XAML
<Frame Name="contentFrame" />
C# code-behind
contentFrame.Content = new Page();
To open it in a new window you could do something like this.
Page p = new Page();
p.Show();
I'm developing metro app using Windows 8 RTM and C#(VS 2012 RTM), I'm stuck with page reload,
Can any one explains me how to reload page with out navigating to same page again.
Brief: I'm developing metro app with multilingual support. When user selects the language I'm overriding primary language by below code
Windows.Globalization.ApplicationLanguages.PrimaryLanguageOverride = "de";
and reload the page by using this code
this.Frame.Navigate(this.GetType());
Language changed to "de",But when i press "Back" on page its navigating same page instead of navigating to previous page.Did i miss something, Can someone please explains me how to do this. Thanks in advance
This will refresh your page:
var _Frame = Window.Current.Content as Frame;
_Frame.Navigate(_Frame.Content.GetType());
_Frame.GoBack(); // remove from BackStack
Handling OnNavigatingFrom() you can save your page's data and state.
Handling OnNavigatingTo() you can load your page's data and state.
As a caveat, my sample does not account for page parameters, you may need to.
Also, another caveat, my sample reloads your page twice. But the GoBack() is necessary to remove the new entry from the BackStack. Unlike WP, Frame does not have Refresh(). Also, the BackStack does not have Remove().
UPDATE
I no longer use the above approach. I use this:
public bool Reload() { return Reload(null); }
private bool Reload(object param)
{
Type type = this.Frame.CurrentSourcePageType;
if (this.Frame.BackStack.Any())
{
type = this.Frame.BackStack.Last().SourcePageType;
param = this.Frame.BackStack.Last().Parameter;
}
try { return this.Frame.Navigate(type, param); }
finally { this.Frame.BackStack.Remove(this.Frame.BackStack.Last()); }
}
I’m not sure I fully understand what you are trying to do, so this may be wrong.
By calling that line of code when you are refreshing the page, you are creating a brand new object of the current type and navigating to it, so this does not save changes the user makes while they are on the current page.
Are you using any type of design pattern? For things like this I use MVVM (using the MVVM light library) which implements a really cool navigation service which will keep stuff like this in check.
Is it possible to acces a control thats located in a content page (withing a content place holder, a multiview control to be more exactp) from the master page?
The situation is, i have a menu with buttons thats located in the master page.
Now in my content page i have 1 content place holder.
In which a multiview with several views is located.
If i press a button in the menu (MasterPage) then it should open the proper view (with its controls) displayed in the content place holder area.
I have set the ActieveViewIndex=0 but i am getting all sorts of wierd behavour.
I have to do something with the ActiveViewIndex++ somewhere but nothing seems to work.
edit::
string a = Request.Querystring["one"]
string b = Request.QueryString["two"]
if ( a == "addOne") // where addone is a redirection to the content page from the master page button
{
mvMultieView.SetActiveView(vView1);
}
else
if ( b == "addTwo")
{
mvMultieView.SetActiveView(vView2);
}
Any suggestions?
Kind Regards.
You can easily do that using find control
View myView = (View)this.Master.FindControl("PlaceHolderFullMain").FindControl("PlaceHolderMain").FindControl("Mymultiview")
The way my team and I accomplished this task (and I don't know that it's the best method, but it was effective) was to use query strings (as you had in your previous question it looks like). We established a standard QS variable called iView that would determine the name of the view in question (not necessarily the control name itself, but some keyword that the content control would respond to). Since all of our pages/controls have a page base class they inherit from, we put a method in the base class (in our case it was at the page level, but in yours a control level might work) that was responsible for getting the requested view. In the control we would have a mechanism (switch perhaps) that would set the activeView. In some cases we just used the actual ID of the control (since it was a mystery to be obfuscated) and avoided the switch altogether.
http://www.mydomain.com/mypage.com?iView=mySecondView
partial class MyControl : System.Web.UI.WebControl
{
// blah blah control stuff
public string getRequestedView()
{
return (Request.QueryString["iView"]) ? Request.QueryString["iView"] : String.Empty;
}
}
...
protected void Page_Load(object sender, EventArgs e)
{
View myView = myMultiView.FindControl(this.getRequestedView());
if(myView != null)
this.MyView.SetActiveView(myView);
}
have you done this change in the Master page or content page?
because i also got the same problem.
I have link buttons in my master page which i need to activate view controls in content page.
the content page is not the currently loaded page.
will this method help for my solution?