I'm trying to make Caliburn Micro find my view, which is located in a ResourceDictionary, to be used in a ContentControl.
<Window x:Class="RSA.UI.Prosit.Sales.Views.GenericPrositDialog"
<!-- ... -->>
<Window.Resources>
<ResourceDictionary>
<ResourceDictionary.MergedDictionaries>
<ResourceDictionary Source="PolicyOverview/PolicyOverviewDialogs.xaml"/>
<!-- ... -->
</ResourceDictionary.MergedDictionaries>
</ResourceDictionary>
</Window.Resources>
<Grid MaxHeight="{Binding MaxWindowHeight}" HorizontalAlignment="Stretch" VerticalAlignment="Stretch">
<ContentControl Content="{Binding}"></ContentControl>
</Grid>
</Window>
In PolicyOverviewDialogs.xaml I have
<DataTemplate DataType="{x:Type vm:NotesViewModel}">
...
How can I get Caliburn Micro's WindowManager to find the view?
Trying things like
_windowManager.ShowDialog(notesVM, null, settings);
_windowManager.ShowDialog(notesVM, "GenericPrositDialogView", settings);
but they all come up short with a message "Cannot find view for NotesViewModel". Anyone has experience with this?
Everything works fine if I make the view its' own file "NotesView.xaml", but that's not what I want.
Related
When I use a LinearGradientBrush (from the new 4.8 version of Xamarin.Forms), I get the followin error:
Autofac.Core.DependencyResolutionException: 'An exception was thrown while activating App.Modules.Loading.LoadingView.'
In the page preview in Visual Studio, it shows the page as expected. When I comment the LinearGradientBrush block, it runs fine.
Do you have any idea why this happens?
Thank you!
Best regards,
Eduardo Luczinski.
<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
x:Class="App.Modules.Loading.LoadingView">
<ContentPage.Background>
<LinearGradientBrush StartPoint="0,0"
EndPoint="0,1">
<GradientStop Color="#3B8476"
Offset="0.1"/>
<GradientStop Color="#00352B"
Offset="1.0"/>
</LinearGradientBrush>
</ContentPage.Background>
<ContentPage.Content>
<StackLayout VerticalOptions="End" HorizontalOptions="FillAndExpand">
<ProgressBar x:Name="loadingBar" VerticalOptions="End" ProgressColor="#FFFF" Progress="0.25"/>
</StackLayout>
</ContentPage.Content>
</ContentPage>
If you want to enable LinearGradientBrush in ContentPage, according to this document,you need to set up experimental flags in your target platforms projects.
On android in your MainActivity class, on ios in AppDelegate Class:
Forms.SetFlags("Brush_Experimental");
Making sure to call SetFlags() before Xamarin.Forms.Forms.Init()
The there is no problem, and it works fine.
I have a template defined in App.Xaml
<ResourceDictionary>
<ControlTemplate x:Key="HomePageTemplate">
<Label Text="{Binding MyLabelText}"/>
</ControlTemplate>
</ResourceDictionary>
And I use it in my Home page
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
xmlns:cv="clr-namespace:Xamarin.Forms;assembly=Xamarin.Forms.CarouselView"
xmlns:local="clr-namespace:App.Converters"
x:Class="App.Views.HomePage"
ControlTemplate="{StaticResource HomePageTemplate}">
</ContentPage>
I set the BindingContext of my Homepage in code behind.
Now shouldn't the ControlTemplate inherit the HomePage's BindingContext ? Because I thought that was the case but my Label doesn't keep the text from MyLabelText. What's the work around to work with Bindings in these templates ?
EDIT:
Using this option
<ResourceDictionary>
<ControlTemplate x:Key="HomePageTemplate">
<Label Text="{TemplateBinding Parent.BindingContext.MyLabelText}"/>
</ControlTemplate>
</ResourceDictionary>
Also does not work for me, because I use the ControlTemplatein the header of the HomePage and not inside it's body.
This works BUT IT'S NOT what I'm looking for:
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
xmlns:cv="clr-namespace:Xamarin.Forms;assembly=Xamarin.Forms.CarouselView"
xmlns:local="clr-namespace:App.Converters"
x:Class="App.Views.HomePage"
>
<ContentView ControlTemplate="{StaticResource HomePageTemplate}" />
</ContentPage>
With ControlTemplate controls the binding is slightly different. Have a look at these docs: https://learn.microsoft.com/en-us/xamarin/xamarin-forms/app-fundamentals/templates/control-templates/template-binding
Assuming that the MyLabelText property is part of the BindingContext of the parent control your code could look like this:
<ResourceDictionary>
<ControlTemplate x:Key="HomePageTemplate">
<Label Text="{TemplateBinding Parent.BindingContext.MyLabelText }"/>
</ControlTemplate>
</ResourceDictionary>
App.xaml should have a BindingContext. Let's call it AppViewmodel, with a namespace vm (or any other key) defined at the top of App.xaml. This AppViewmodel can be bound to from within the ControlTemplate. In this example a button (placed in a stacklayout) is bound to a command named AppCommand, which resides in AppViewmodel. When this ControlTemplate is applied in a ContentPage, it binds to the ViewModel of App.xaml, not to the VM of that particular ContentPage. Perhaps the latter is also possible, for example by choosing the right settings for RelativeSource and AncestorType, but I haven't figured that out.
see also
<ControlTemplate x:Key="HomePageTemplate">
<StackLayout BindingContext="{Binding Source={RelativeSource TemplatedParent}}">
<Button
Command="{Binding Source={RelativeSource AncestorType={x:Type vm:AppViewModel}}, Path=AppCommand}"
/>
</StackLayout>
</ControlTemplate>
If anyone its interested, the way this works its just adding Path after TemplateBinding, specifying BindingContext on it and then the public var name:
<ResourceDictionary>
<ControlTemplate x:Key="HomePageTemplate">
<Label Text="{ TemplateBinding Path=BindingContext.MyLabelText }"/>
</ControlTemplate>
</ResourceDictionary>
I have changed the default color of the navigation bar by using these codes in app.xaml as I am unable to make it transparent on iOS devices:
<Style TargetType="NavigationPage">
<Setter Property="BarBackgroundColor" Value="#0a82b8" />
<Setter Property="BarTextColor" Value="#ffffff" />
</Style>
Now, there is an unnecessary navigation bar separator on iOS:
On Microsoft's official website, it says these codes can be helpful:
This platform-specific hides the separator line and shadow that is at
the bottom of the navigation bar on a NavigationPage. It's consumed in
XAML by setting the NavigationPage.HideNavigationBarSeparator bindable
property to false:
<NavigationPage ...
xmlns:ios="clr-namespace:Xamarin.Forms.PlatformConfiguration.iOSSpecific;assembly=Xamarin.Forms.Core"
ios:NavigationPage.HideNavigationBarSeparator="true">
</NavigationPage>
Alternatively, it can be consumed from C# using the fluent API:
using Xamarin.Forms.PlatformConfiguration;
using Xamarin.Forms.PlatformConfiguration.iOSSpecific;
public class iOSTitleViewNavigationPageCS : Xamarin.Forms.NavigationPage
{
public iOSTitleViewNavigationPageCS()
{
On<iOS>().SetHideNavigationBarSeparator(true);
}
}
Source: Hiding the Navigation Bar Separator on a NavigationPage
The problem is that when I want to paste the ios:NavigationPage.HideNavigationBarSeparator="true" property into the <NavigationPage>tag, it gives this error:
No property, bindable property, or event found for 'HideNavigationBarSeparator', or mismatching type between value and property.
My full codes are:
<?xml version="1.0" encoding="utf-8"?>
<MasterDetailPage xmlns="http://xamarin.com/schemas/2014/forms" xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml" xmlns:local="clr-namespace:My.App" x:Class="My.App.MainPage">
<MasterDetailPage.Master>
<ContentPage Title="Menu" BackgroundColor="#0a82b8" Icon="menu.png">
<StackLayout Orientation="Vertical">
<ListView x:Name="navigationDrawerList" RowHeight="55" SeparatorVisibility="None" BackgroundColor="#ffffff" ItemSelected="OnMenuItemSelected">
<ListView.ItemTemplate>
<DataTemplate>
<ViewCell>
<!-- Main design for our menu items -->
<StackLayout VerticalOptions="FillAndExpand" Orientation="Horizontal" Padding="20,10,0,10" Spacing="20">
<Label Text="{Binding Title}" FontSize="Large" VerticalOptions="Start" HorizontalOptions="CenterAndExpand" TextColor="#28DDFF" FontAttributes="Bold" />
</StackLayout>
</ViewCell>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
</StackLayout>
</ContentPage>
</MasterDetailPage.Master>
<MasterDetailPage.Detail>
<NavigationPage xmlns:ios="clr-namespace:Xamarin.Forms.PlatformConfiguration.iOSSpecific;assembly=Xamarin.Forms.Core"
ios:NavigationPage.HideNavigationBarSeparator="true">
</NavigationPage>
</MasterDetailPage.Detail>
</MasterDetailPage>
Here is the tutorial which I followed for the MasterDetail navigation. The file which has <NavigationPage> tag is named as MainPage.xaml
You can use a custom renderer to hide that shadow:
[assembly: ExportRenderer(typeof(NavigationPage), typeof(CustomNavigationPage))]
namespace CustomNavigationPage.iOS
{
public class CustomNavigationPage : NavigationRenderer
{
protected override void OnElementChanged(VisualElementChangedEventArgs e)
{
base.OnElementChanged(e);
NavigationBar.SetBackgroundImage(new UIKit.UIImage(), UIKit.UIBarMetrics.Default);
NavigationBar.ShadowImage = new UIKit.UIImage();
}
}
}
While you have accepted the answer, this one is more precise - you haven't followed the instructions that you have pasted from the site as you have ommited this line:
xmlns:ios="clr-namespace:Xamarin.Forms.PlatformConfiguration.iOSSpecific;assembly=Xamarin.Forms.Core"
Place UINavigationBar.Appearance.ShadowImage = new UIImage(); inside the public override bool FinishedLaunching(UIApplication app, NSDictionary options) method within AppDelegate.cs file. AppDelegate.cs resides within the iOS project of Xamarin.Forms
I want to bind to a variable from inside a CustomControl referenced in a ListView DataTemplate
This is the situation:
I have a custom control containing a ListView with many DataTemplates to display the various ViewCell (it's basically a set of dynamic fields that must be displayed according to their "type").
<?xml version="1.0" encoding="UTF-8"?>
<ContentView xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
xmlns:s4gvForms="clr-namespace:S4GVMobile.Forms;assembly=S4GVMobile"
xmlns:s4gvControls="clr-namespace:S4GVMobile.Controls;assembly=S4GVMobile"
x:Class="S4GVMobile.Controls.AttributesList"
x:Name="S4GVAttributesListControl"
>
<ContentView.Resources>
<ResourceDictionary>
<!-- MANY DATA TEMPLATES HERE, ONLY ONE LEFT FOR REFERENCE -->
<DataTemplate x:Key="s4gvAttributePictureTemplate">
<ViewCell x:Name="s4gvAttributePictureViewCell">
<ViewCell.View>
<StackLayout Orientation="Vertical">
<Label Text="{Binding Attribute.Key}" />
<s4gvControls:AttributePicture ParentID="{Binding Source={x:Reference s4gvAttributePictureViewCell}, Path=Parent.BindingContext.EntityID}" AttributeValue="{Binding .}" />
</StackLayout>
</ViewCell.View>
</ViewCell>
</DataTemplate>
<!-- ... -->
<!-- AGAIN, LONG LIST IN THE SELECTOR -->
<s4gvForms:AttributeDataTemplateSelector x:Key="s4gvAttributeDataTemplateSelector"
AttributePictureTemplate="{StaticResource s4gvAttributePictureTemplate}"
/>
</ResourceDictionary>
</ContentView.Resources>
<StackLayout>
<ListView x:Name="s4gvAttributes" HasUnevenRows="True" ItemTemplate="{StaticResource s4gvAttributeDataTemplateSelector}" ItemsSource="{Binding AttributeValues}" />
</StackLayout>
I'm passing to this custom control both the list of items (required by the ListView) and an additional EntityID.
<s4gv:AttributesList x:Name="s4gvSerialAttributes" AttributeValues="{Binding Serial.AttributeValues}" EntityID="{Binding Serial.SerialID}" VerticalOptions="FillAndExpand"/>
The custom control has the required bindable properties (AttibuteValues and EntityID) and relies on a dedicated ViewModel
I need to retrieve the EntityID from inside the DataTemplate (and put it in the ParentID property); this value is in the custom control's ViewModel but it is "outside" the ListView's DataTemplates. I've tried using the Parent.BindingContext (it works on Command and CommandParameter) but it seems that it can only go up to the ListView's context and not higher though I need to move one further step up to the CustomControl itself.
<s4gvControls:AttributePicture ParentID="{Binding Source={x:Reference s4gvAttributePictureViewCell}, Path=Parent.BindingContext.EntityID}" AttributeValue="{Binding .}" />
Any idea? I'm happy to restructure the whole thing if required.
I have multiple ContentPage xaml files in my Xamarin project. I want to embed a shared piece of xaml into each ContentPage. There is nothing particularly special about the shared piece of xaml (it does't need to do anything platform specific). Shouldn't it be just as easy as embedding a tag in the xaml of the ContentPage to include the shared xaml file? Can someone point me in the right direction?
Thank you very much IdoT, It did work for me, but after adding some lines.
As this will help in making templates/custom controls/sub forms, easily added/shared across Xamarin.Forms.
Here is my full work based on your suggestion, so it can be used as is with others:
HeaderNavigationBar.xaml
<?xml version="1.0" encoding="utf-8" ?>
<StackLayout xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
x:Class="App9.MVC.Views.HeaderNavigationBar"
Orientation="Horizontal"
HorizontalOptions="FillAndExpand"
Padding="10"
ackgroundColor="White">
<Button Text="Internal 1" />
<Button Text="Internal 2" />
</StackLayout>
As you can see, added:
xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
and in the HeaderNavigationBar.cs, it was declared as StackLayout:
HeaderNavigationBar.cs
using Xamarin.Forms;
namespace App9.MVC.Views
{
public partial class HeaderNavigationBar : StackLayout
{
public HeaderNavigationBar()
{
InitializeComponent();
}
}
}
then for the page that will hold it/show it:
MainView.xaml
<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
xmlns:common="clr-namespace:App9.MVC.Views;assembly=App9"
x:Class="App9.MVC.Views.MainView">
<StackLayout Padding="0,0,0,20">
<common:HeaderNavigationBar>
<Button Text="External 1" />
</common:HeaderNavigationBar>
<Button Text="Test Button 1
x:Name="btnPage1"
Clicked="btnPage1_clicked" />
</StackLayout>
</ContentPage>
As you can notice, the namespace has the full path, in the MainView:
xmlns:common="clr-namespace:App9.MVC.Views;assembly=App9"
Also, you can notice that there is a button called External 1, this will also show with the
Internal buttons, as the control is a StackLayout, so it can handle adding more controls.
Screenshot:
Also for Page inside another Page:
https://github.com/twintechs/TwinTechsFormsLib
http://blog.twintechs.com/advanced-xamarin-forms-techniques-for-flexible-and-performant-cross-platform-apps-part-5-page-in-page-embedding
Again thanks goes to IdoT.
You can take the parent child of your ContentPage (for example, a StackLayout that wraps all the children), put it in an external xaml file,
and then include that component in each one of your ContentPages.
The external xaml file will be a StackLayout type, rather than a ContentPage.
Edit - added a code sample:
Let's add a header StackLayout: we add a code behind class:
public partial class HeaderNavigationBar
{
public HeaderNavigationBar()
{
InitializeComponent();
}
}
Then add the XAML code:
<StackLayout x:Class="HeaderNavigationBar"
Orientation="Horizontal"
HorizontalOptions="FillAndExpand"
Padding="10"
BackgroundColor="White">
<Image Source="burger_icon"
HorizontalOptions="StartAndExpand"
Aspect="AspectFit">
<Image.GestureRecognizers>
<TapGestureRecognizer Command="{Binding SlideNavigationDrawerCommand}" />
</Image.GestureRecognizers>
</Image>
</StackLayout>
And finally, in the page where you want to reuse your component - add this reference:<HeaderNavigationBar />.