Change between pages in WPF - c#

I want to make a layout like the one used in any website - the header, sidebar and footer stay the same but the center part. I have multiple pages/windows to show in a wpf blend C# application and they are totally different. For example, stackoverflow has a layout for the homepage and another one for each Question. Here's another exemple:
I had to do that in a previous project and I used a single grid layout and then, for each page, I had to hide() all of them and show that each one on top -
What's the trick? How can I do the same thing in a wpf application? In a typical C# application I would have to open a child window each time but that seems ugly these days.
Thank you in advance!

If you are going to use Pages in WPF, then you will need to read the Navigation Overview page on MSDN. In short however, you can navigate between Pages in a WPF Application by using the NavigationService Class. To change the page from code behind, you could do something like this:
NextPage page = new NextPage();
NavigationService.Navigate(page);
To let the users change the Page, you can use the Hyperlink Class in your Pages:
<Hyperlink NavigateUri="pack://application:,,,/AppName;component/Pages/NextPage.xaml">
Navigate to Next Page
</Hyperlink>
To get your desired page setup, you will have to load your Pages into a Frame, which you can then layout wherever you like in MainWindow.xaml:
<Frame Source="pack://application:,,,/AppName;component/Pages/SomePage.xaml" />

Sounds like you need a custom usercontrol and some databinding.
You can declare DataTemplates in XAML as resources with the model type as key, so that WPF chooses the correct DataTemplate automatically:
Have a main ViewModel, which exposes a ImageSourceViewModel property. This property would either return a CameraSourceViewModel or a FileSourceViewModel, as appropriate.
In your page, the DataContext would be the main ViewModel, and you'd have XAML like this:
Then,
<Page x:Class="Page1"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:my="clr-namespace:WpfApplication1"
mc:Ignorable="d"
d:DesignHeight="300" d:DesignWidth="300"
Title="Page1">
<Page.Resources>
<DataTemplate DataType="{x:Type my:CameraSourceViewModel}">
<my:CameraSourceView/>
</DataTemplate>
<DataTemplate DataType="{x:Type my:FileSourceViewModel}">
<my:FileSourceView/>
</DataTemplate>
</Page.Resources>
<Grid>
<ContentControl Content="{Binding ImageSourceViewModel}"/>
</Grid>
I should point out that this example uses the MVVM pattern to allow the viewmodel layer to decide on the content in the middle. Hopefully this is clear enough, if not, give me a shout and I'll try to expand it!

Let's say I have main view model where I've created a CurrentPage property that will tell which page you want to display.
/// <summary>
/// Returns the page ViewModel that the user is currently viewing.
/// </summary>
public ViewModelBase CurrentPage
{
get { return _currentPage; }
private set
{
if (value != _currentPage)
{
if (_currentPage != null)
_currentPage.IsCurrentPage = false;
_currentPage = value;
if (_currentPage != null)
_currentPage.IsCurrentPage = true;
RaisePropertyChanged(() => CurrentPage);
}
}
}
And in your xaml you can bind your page under some control. Let's say I am doing it inside a Border element.
<!-- CURRENT PAGE AREA -->
<Border Background="White" Grid.Column="1" Grid.Row="0">
<HeaderedContentControl Content="{Binding Path=CurrentPage}"
Header="{Binding Path=CurrentPage.DisplayName}" />
</Border>
You can define view to your view model in resources just like this:
(partially complete XAML)
<UserControl x:Class="BAT.View.BATWizardView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:view="clr-namespace:BAT.View"
xmlns:viewmodel="clr-namespace:BAT.ViewModel"
mc:Ignorable="d"
d:DesignHeight="350" d:DesignWidth="600">
<UserControl.Resources>
<!-- These four templates map a ViewModel to a View. -->
<DataTemplate DataType="{x:Type viewmodel:MyComparisonViewModel1}">
<view:MyView1 />
</DataTemplate>
<DataTemplate DataType="{x:Type viewmodel:MyComparisonViewModel2}">
<view:MyView2 />
</DataTemplate>
</UserControl.Resources>
<Grid>
<Border Background="White" Grid.Column="1" Grid.Row="0">
<HeaderedContentControl Content="{Binding Path=CurrentPage}"
Header="{Binding Path=CurrentPage.DisplayName}" />
</Border>
</Grid>
</UserControl>
See if that helps.

Related

UWP+Prism MVVM - How do I set the value of a view model property via XAML?

I have a property in a view model which I would like to be able to set via the XAML but I can't figure out how to do it.
I have a pretty basic user control (containing a list of items), two of which are to be placed on a page and I would like to be able to set one to be a 'Source' (defined by an enum) and one to be a 'Target'.
[The code below has been stripped down quite a bit so apologies if I've accidentally made some mistakes or missed something out.]
My enumeration is:
public enum ConversionSide
{
Source, // Convert something FROM whatever is here.
Target // Convert something TO whatever is here.
}
I have a page which looks like this:
<Page
x:Class="MyApp.Views.ConverterPage"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:models="using:MyApp.Models"
xmlns:my="using:MyApp.Controls"
xmlns:prismMvvm="using:Prism.Windows.Mvvm"
prismMvvm:ViewModelLocator.AutoWireViewModel="True"
Style="{StaticResource PageStyle}"
mc:Ignorable="d">
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="1*" />
<ColumnDefinition Width="1*" />
</Grid.ColumnDefinitions>
<my:SelectorPage Name="SourceSelector" Grid.Column="0" />
<my:SelectorPage Name="TargetSelector" Grid.Column="1" />
</Grid>
</Page>
...where SelectorPage is a user control (I've called it a 'Page' to make the Prism AutoWire work but that's not the issue here) containing a list of items (all working fine) which looks like this...
<UserControl
x:Class="MyApp.Controls.SelectorPage"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:models="using:MyApp.Models"
xmlns:my="using:MyApp.Controls"
xmlns:prismMvvm="using:Prism.Windows.Mvvm"
prismMvvm:ViewModelLocator.AutoWireViewModel="True"
mc:Ignorable="d">
<ListView
Grid.Column="0"
ItemsSource="{x:Bind ViewModel.MyList, Mode=OneWay}"
SelectedItem="{x:Bind ViewModel.MySelectedItem, Mode=TwoWay}">
<ListView.Header>
<TextBlock Margin="0,8,0,8" HorizontalAlignment="Center" FontStyle="Italic" Text="Header Text" />
</ListView.Header>
<ListView.ItemContainerStyle>
<Style TargetType="ListViewItem">
<Setter Property="HorizontalContentAlignment" Value="Stretch" />
</Style>
</ListView.ItemContainerStyle>
<ListView.ItemTemplate>
<DataTemplate x:DataType="models:MyListItem">
<my:MyListItemTemplate />
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
</UserControl>
..with code behind as...
public sealed partial class SelectorPage : UserControl
{
private SelectorViewModel ViewModel => DataContext as SelectorViewModel;
public SelectorPage()
{
this.InitializeComponent();
}
}
SelectorViewModel looks like this...
public class SelectorViewModel : ViewModelBase
{
private ConversionSide _side;
public ConversionSide Side
{
get { return _side; }
set { SetProperty(ref _side, value); }
}
// Many lines have been omitted for 'clarity'.
}
I would like to be able to set the Side property of SelectorViewModel in XAML like this...
<my:SelectorPage Name="SourceSelector" Grid.Column="0" Side="Source" />
<my:SelectorPage Name="TargetSelector" Grid.Column="1" Side="Target" />
(Once Side has been set, I do not expect it to ever change.)
How can I do this?
I've looked at using a dependency property but I can't get it to change the property in SelectorViewModel. When I add one in SelectorPage it's visible in the XAML and I can set it but it doesn't actually do anything so I'm probably not using it right. Putting a dependency property in the view model doesn't sound right to me but I could be wrong.
I've had a look around the web - Microsoft documentation, blogs, articles, stack overflow, etc. - but I can't find anything that explains things well enough for me to figure out what I'm supposed to do. The writings I've found seem to be exclusively about getting information from a bound property - which I'm okay with - but what I'm after is setting a property from the XAML.
Can anyone give my any clues please? I don't know if I'm just a tiny step away from getting what I want or if I'm miles away.
This would set the Side property of the SelectorPage control to Source:
A view sets the property of a view model by two-way bind to it. For example, the following TextBox sets the string property of a view model called Test when you change the text in the TextBox:
<TextBox Text="{Binding Test, Mode=TwoWay}" />
So setting the property of a view model from the view typically applies to controls that handles some kind of input. Any default value of a source property should be defined in the view model:
private ConversionSide _side = ConversionSide.Source;
You shouldn't define the default values in the view.

Calibrun.Micro Sample/Feature/UWP : What is "cm:Bind.Model="{Binding}"

Here is Calibrun.Micro example with UWP.
in Bubbling sample, in this file,
there is this line
<Grid cm:Bind.Model="{Binding}">
What is mean ? Why does it necessary ?
I thought Next line is enough for send $dataContext
<Button x:Name="Message" cm:Message.Attach="SelectPhrase($dataContext)" Margin="0,12" />
Please advice me....
Let's analyze the code as quite some things are a bit obscure in Caliburn.Micro as it works through convention:
<Page
x:Class="Features.CrossPlatform.Views.BubblingView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:cm="using:Caliburn.Micro"
mc:Ignorable="d">
<StackPanel Background="{ThemeResource ApplicationPageBackgroundThemeBrush}">
<TextBlock Text="actions" Style="{StaticResource SubheaderTextBlockStyle}" Margin="40,10,40,0"/>
<StackPanel Margin="40,20">
<ItemsControl x:Name="Phrases">
<ItemsControl.ItemTemplate>
<DataTemplate>
<Grid cm:Bind.Model="{Binding}">
<Button x:Name="Message" cm:Message.Attach="SelectPhrase($dataContext)" Margin="0,12" />
</Grid>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
</StackPanel>
</StackPanel>
</Page>
First of all, the page's datacontext (viewmodel) is set through naming convetion. This viewmodel can be found here. As you can see, this viewmodel has a Phrases property and a SelectPhrase(MessageActivityViewModel phrase) method.
If we go down the tree, we have an <ItemsControl x:Name="Phrases"> which binds to the Phrases property, which is a collection of MessageActivityViewModel.
An ItemsControl needs a way to present the items, which is defined in the DataTemplate. This template has a Grid as root object. If the Grid would not use {Binding}, it would inherit the datacontext from the template, which is the current element being rendered (a single MessageActivityViewModel). However, we want to call the SelectPhrase method on the BubblingViewModel and not on the MessageActivityViewModel. To be able to do that, we use {Binding} to tell the Grid binds to the page's viewmodel instead of to the single rendered MessageActivityViewModel.
What the Button does, is sending the datacontext object (being the rendered MessageActivityViewModel item) back to your viewmodel.
$dataContext:
Passes the DataContext of the element that the ActionMessage is attached to. This is very useful in Master/Detail scenarios where the ActionMessage may bubble to a parent VM but needs to carry with it the child instance to be acted upon.
Source: http://caliburnmicro.com/documentation/cheat-sheet

How to set up XAML View Content in Different XAML

I just programm a Windows Universal App and I want to set up an
empty MainView.xaml witch provides the content from different User Control xamls just like in javafx and switch then on the fly in the MainViewxaml.cs like:
Pseudo Code:
this.Content = Login.xaml
Main.xaml Pseudo Code:
<Grid Background="{ThemeResource ApplicationPageBackgroundThemeBrush}">
<UserControl x:Name="UserControl"/>
</Grid>
My Question is:
How can I do this in a Windows Universal app ?
Use a frame and pages. Or if you don't want to do that, use a ContentControl.
<Grid Background="{ThemeResource ApplicationPageBackgroundThemeBrush}">
<ContentControl x:Name="ContentControl">
<UserControl x:Name="UserControl"/>
</ContentControl>
</Grid>
And than you can say ContentControl.Content = new YourUserControl();

Put a View Control in its ViewModel

I'm developing a Windows 8.1 Store app with C# and .Net Framework 4.5.1.
I'm trying to bind Password.SecurePassword to a ViewModel, and reading this SO answer I found a way to do it: Put the PasswordBox in my ViewModel.
But I don't know how to do it. I know how to bind Dependency Properties, but I don't know how to put that control on my ViewModel. This is my XAML:
<Page
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
DataContext="{Binding MainViewModel, Source={StaticResource Locator}}"
mc:Ignorable="d">
<Grid Background="{ThemeResource ApplicationPageBackgroundThemeBrush}">
<PasswordBox x:Name="userPassword" />
</Grid>
</Page>
What do I have to do?
You have several options but I'll just give you the basic option without third party libraries.
In your Page constructor. You can do something like this.
public Page()
{
var mainViewModel = this.DataContext as MainViewModel;
if(mainViewModel != null)
{
mainViewModel.PasswordBox = userPassword;
}
}
You can also set it on the Loaded event of the View and set the PasswordBox to the ViewModel.

View is not being resolved with Toolbar ItemsSource

It doesn't seem like the Caliburn Micro framework is retrieving my SinglePaintToolbarView when it is binded as a list of buttons in the toolbar of the ShellView. I would like the buttons to just display their text content when they are added to the toolbar. But, instead I'm getting this:
There doesn't appear to be any clickable buttons in the toolbar. I know my plugins are being loaded successfully, because I was able to bind one of the plugins in the list as a ContentControl and the view appeared. It just doesn't seem to work when I try to bind a list of the plugins in a toolbar.
Here is what I have:
ShellView.xaml
<UserControl x:Class="Starbolt.Views.ShellView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
mc:Ignorable="d"
d:DesignHeight="300" d:DesignWidth="300">
<Grid>
<ToolBarTray>
<ToolBar ItemsSource="{Binding Path=ToolbarPlugins}"/>
</ToolBarTray>
</Grid>
</UserControl>
ShellViewModel.cs
[Export(typeof(IShell))]
public class ShellViewModel : PropertyChangedBase, IShell
{
[ImportMany(typeof(IToolbarPlugin))]
private IEnumerable<IToolbarPlugin> _toolbarPlugins = null;
public IEnumerable<IToolbarPlugin> ToolbarPlugins { get { return _toolbarPlugins; } }
}
SinglePaintToolbarView.xaml
<UserControl x:Class="Starbolt.Plugin.SinglePaintTool.Views.SinglePaintToolView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
mc:Ignorable="d"
d:DesignHeight="128" d:DesignWidth="32">
<Button Name="btnSinglePaintTool" Content="Single Paint Tool" Width="128" Height="32"/>
</UserControl>
SinglePaintToolViewModel.cs
[Export(typeof(IToolbarPlugin))]
public class SinglePaintToolViewModel : IToolbarPlugin
{
}
Basically, your design seems to be working. If you replace
<ToolBarTray>
<ToolBar x:Name="ToolbarPlugins"/>
</ToolBarTray>
(note that you do not need to bind the ItemsSource explicitly, you can just as well use the Caliburn Micro property name conventions) with the following:
<ListBox x:Name="ToolbarPlugins"/>
the SinglePaintToolView button is displayed as intended.
I suspect that the problem is with the ToolBar ControlTemplate, which most certainly restricts the toolbar items layout more than what for example a ListBox ControlTemplate does.
So my guess is that if you really want to use the ToolBar control to display your IToolbarPlugin views, you will probably have to design a dedicated ToolBar control template in your project.
Alternatively, you could implement a toolbar replacement using e.g. ListBox. This could be a start:
<ListBox x:Name="ToolbarPlugins">
<ListBox.ItemsPanel>
<ItemsPanelTemplate>
<StackPanel Orientation="Horizontal" />
</ItemsPanelTemplate>
</ListBox.ItemsPanel>
</ListBox>

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