I need to show ContentDialog that is not attached to any page.
Currently I construct it dynamically in the code.
How can I define it in XAML?
By adding a UserControl item to your project and changing its base type to ContentDialog with the following Body:
<ContentDialog .../>
-or-
<ContentDialog>
singleObject
</ContentDialog>
-or-
<ContentDialog>stringContent</ContentDialog>
See MSDN link
Related
The UWP XAML ItemsControl is the basis for many complicated XAML classes, like ListView and GridView.
The documentation Item containers and templates describes 2 key parts of these controls:
Data template
Control template
These parts combine to create the final view:
Container controls (such as ListViewItem and GridViewItem) consist of two important parts that combine to create the final visuals shown for an item: the data template and the control template.
In practice, developers specify the data template by specifying a DataTemplate in ListView.ItemTemplate (or GridView.), and they can customize the control template by providing a Style (TargetType="ListViewItem") to ListView.ItemContainerStyle.
Developers can also customize the ListView.ItemsPanel (which is an ItemsStackPanel by default), and the default Template for the ListView.ItemContainerStyle contains a ListViewItemPresenter. The documentation for Item containers and templates mentions these, too.
That raises the question:
When I add a ListView (or GridView or any ItemsControl) to my code, what am I actually adding? What can I customize? How is my data displayed?
As far as I can determine, the ListView looks something like:
ListView
Renders its Template which somehow renders:
ItemsPanel
Renders its ItemsPanelTemplate which is:
ItemsStackPanel
Renders, for each item:
ListViewItem
Renders its Template, which is:
ListViewItemPresenter
Somehow renders:
ListView.ItemTemplate
But this is unclear to me.
Disclaimer: I work for Microsoft.
you can customize anything in xaml
under the hood, both ListView and GridView can be created by ItemsControl, but their default template have some customization built-in already.
if you want to understand when to use which, here is a page:
https://learn.microsoft.com/en-us/windows/uwp/design/controls-and-patterns/lists
your data will be set to the ItemsSource if using binding, for example
<ListView
ItemsSource="{Binding Source={StaticResource itemsViewSource}}"
>...
or you can set directly.
from your question, it sounds like you may not have understood the basis, so maybe reading this series will help you:
http://drwpf.com/blog/itemscontrol-a-to-z/
it's for wpf, but the fundamental is the same, you can apply it to UWP as well.
I am new to Xamarin development. I created new Xamarin XAML App(Xamarin.Forms Portable). In Portable Project there where MainPage.Xaml by default. To create MVVM Model I created three new Folders- Views, ViewModels, and Models. Now I added new MainPage.Xaml in Views folder and was going to delete the default MainPage.Xaml page. But here I see some difference in both pages. The default MainPage.Xaml have xmlns:local="clr-namespace:Test" but the new MainPage.Xaml does not. Again the new MainPage.Xaml have <Label Text="{Binding MainText}" VerticalOptions="Center" HorizontalOptions="Center" /> but the default one does not. The screenshots are:
What does these MarkUp mean.Why there is a difference. Does something needs to be changed. Can I delete the default MainPage.Xaml or should i copy it in Views.Does I need to copy the Markup from the default Page to the new one. If so why?
Thanks in advance
Both pages are identical, and will display in the same way.
On the second, there's an additional Xml namespace declaration:
xmlns:local="clr-namespace:Test"
It's only a declaration. You could remove it, or add it to the other page without effect. It's purpose is to be able to reference custom views declared in the current assembly and in the namespace (c# namespace, this time) Test, like this:
<ContentPage
...
xmlns:local="clr-namespace:Test"
x:Class="Test.MainPage">
<local:MyAwesomeView />
</ContentPage>
Awesome that you have decided to start with Xamarin and Xamarin.Forms!
While I understand you might be having these questions, this is some very basic XAML knowledge. The short answer is: you don't need to worry about it.
The long answer:
The reason that there is a difference in these pages is simply because it's just a template and whoever at Xamarin created the template for the project can be a different person than who created the template for a new XAML page. So they solved it different ways. Or maybe he had a good/bad day, who knows.
The Label in the first page is simply there to show you how to get started and so you won't start with an empty screen.
The extra namespace xmlns:local="clr-namespace:Test" is actually redundant in this new page but is already there so you can use the classes in your project.
It is actually the equivalent of the using list at the top of your classes. So whenever you need something from a different namespace you have to declare it there. So if you create a folder 'Controls' you can add a attribute xmlns:controls="clr-namespace:Test.Controls".
Note how I changed local to controls, this is the prefix you will use to define your instance. Also I have added the right namespace Test.Controls. Now if you want te show something on screen, in your XAML from the controls namespace, go like this:
<ContentPage xmlns:controls="clr-namespace:Test.Controls" x:Class="Test.MainPage">
<!-- some stuff here -->
<controls:ReusableControlHere />
</ContentPage>
Where ReusableControl can be your own version of a Label, Button or virtually anything.
I trying to display an HTML from a model inside of WebView control. After some googling, I realised that I cannot use the Source property as it is meant to be populated only with URL or URI.
After a couple additional searches, I came across HtmlWebViewSource but I can't find a single example of using HtmlWebViewSource via XAML.
Does anyone have a clue how to define an instance of HtmlWebViewSource in XAML, bind HTML from the model and assign it to WebView
thanks!
To answer myself
<WebView x:Name="_webView" HorizontalOptions="Fill" VerticalOptions="EndAndExpand">
<WebView.Source>
<HtmlWebViewSource
Html="{Binding HTMLSource}" />
</WebView.Source>
</WebView>
I can not display a ContentDialog without Borders. If I set BorderBrush="Transparent" or BorderThickness="0 0 0 0" the Borders remain.
Is there any way to get rid of them?
When ContentDialog displays, the properties of BorderBrush and BorderThickness are invisible. To create a border you need to specify custom content that has a border. This post can be helpful.
Besides, there are several other ways to do so:
1) As blueeyes said: You can take some trouble to modify the default ControlTemplate. Here you can find explanations of ContentDialog's style and template
2) You can create an customized user dialog derived from ContentDialog, where you can define your own style. MSDN has a simple example.
Maybe you can work with the ControlTemplateof it there you can change the whole style of it but I warn you just edit a copy of it and it will be a lot of work to do.
Hope my answer helps you :)
There is a tricks which works for me : when you define your ContentDialog (maybe in the code behind), you can override this resource :
Application.Current.Resources["ContentDialogBorderWidth"] = new Thickness(0);
I fund this resource on the style page of ContentDialog of Microsoft here
When using traditional {Binding} syntax you could specify element name to point to a specific control on the page, and be able to access its properties. For example if the page is named page you could do:
{Binding ElementName=Page, Path=Name}
With the {x:Bind} syntax it says
With x:Bind, you do not need to use ElementName=xxx as part of the
binding expression. With x:Bind, you can use the name of the element
as the first part of the path for the binding because named elements
become fields within the page or user control that represents the root
binding source.
So for the example above in {x:Bind} would be
{x:Bind page.Name}
Which works fine, until it is inside a data template (for example a ListView's ItemTemplate). In which case it no longer works as it is looking for Page on the data type specified which leads to the following error (assuming my data type is customer):
XamlCompiler error WMC1110: Invalid binding path 'Page.Name' :
Property 'Page' can't be found on type 'Customer'
What is the solution to use {x:Bind} syntax with datatemplates and access controls outside the data template?
Example code is available here (note specific commit)
As far as I know at this point in time there is no way to directly bind to a property of a control using the x:bind method as it does not support the element name inside of its binding definition.
That does not mean you cant bind to a control inside a dataTemplate you can still do something like this to access controls but you just aren't able to use the compiled binding x:Bind syntax.
<DataTemplate x:DataType="local:Customer">
<StackPanel Orientation="Vertical">
<Button Content="{Binding Name, ElementName=page}" />
<TextBlock Text="{x:Bind Title}" />
</StackPanel>
</DataTemplate>
The reason for the error you are getting is due to the way data templates parent their datasource. The x:Bind binding cannot reference a control object and your Customer type does Page.Name property or path. As shown above the only real way of accessing user control properties outside of your control only using XAML is to resort back to the standard binding mechanism.
I hope this answers your question.