How to convert from float to std::wstring - slider

I want to know the proper way to convert from "Float" to "std::wstring".
Xaml file
<Page
x:Class="TD2_WinUI3.MainPage"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="using:TD2_WinUI3"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
mc:Ignorable="d">
<StackPanel Orientation="Horizontal" HorizontalAlignment="Center" VerticalAlignment="Center">
<Slider AutomationProperties.Name="Slider with ticks" Header="headerString" Width="300" TickFrequency="10" TickPlacement="Outside" ValueChanged="slider_ValueChanged" />
<TextBlock x:Name="textBlock1" Margin="0,0,0,10" Text="Current value: 0" />
</StackPanel>
</Page>
Cpp File
void MainPage::slider_ValueChanged(Windows::Foundation::IInspectable const&, Microsoft::UI::Xaml::Controls::Primitives::RangeBaseValueChangedEventArgs const& args)
{
std::wstring msg = static_cast<float>(L"Current value: {0:s}", args.NewValue());
textBlock1().Text(msg);
}
That's my piece of code throwing me that error:
E0415 no suitable constructor exists to convert from "float" to "std::basic_string<wchar_t, std::char_traits<wchar_t>, std::allocator<wchar_t>>"


#include <sstream>
std::wstringstream wss;
wss << 1.4f;
auto result = wss.str(); // what you want

Related

How to bind properties for a custom user control properly in avalonia ui

I am trying to display a text on a custome user control. I want that text to be passed via a mainview
this is the code I have:
MainView.axaml
<cc:Slot Grid.Row="0" Grid.Column="1" Dot="Number one"/>
<cc:Slot Grid.Row="0" Grid.Column="2" Dot="Number two"/>
This is my custom user control:
Slot.axaml
<UserControl xmlns="https://github.com/avaloniaui"
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:controls="clr-namespace:Avalonia.Controls;assembly=Avalonia.Controls"
mc:Ignorable="d" d:DesignWidth="800" d:DesignHeight="450"
xmlns:cc="clr-namespace:Diagnostica.CustomControls;assembly=Diagnostica.CustomControls"
x:Class="Diagnostica.CustomControls.OmniSlot">
<Button>
<TextBlock Text="{Binding Dot}"/>
</Button>
</Grid>
</Button>
</UserControl>
and its .cs file"
Slot.axaml.cs
public string Dot
{
get => GetValue(DotProperty);
set => SetValue(DotProperty, value);
}
public static readonly StyledProperty<string> DotProperty =
AvaloniaProperty.Register<Slot, string>(nameof(Dot), defaultValue: "Black");
what i get like this is a disabled box. How can this get fixed?

View:
<Rectangle Stroke="{TemplateBinding DotColor}" StrokeThickness="2" Width="20" Height="20" Fill="{TemplateBinding DotColorBrush}" VerticalAlignment="Top" HorizontalAlignment="Right"/>
ViewModel:
public static readonly StyledProperty<string> DotColorProperty = AvaloniaProperty.Register<OmniSlotControl, string>(nameof(DotColor), "Red");
public string DotColor
{
get => GetValue(DotColorProperty);
set
{
SetValue(DotColorProperty, value);
DotColorBrush = Avalonia.Media.Brush.Parse(value);
}
}

WinUI3: Why does the top area of the NavigationView look different?

The default appearance of the NavigationView in WinUI3 Gallery or an app created with a template studio has a space at the top. However, it looks different in apps created with Visual Studio default templates.I don't think it's controlled by the ViewModel or anything else. Why does it look different?
<!--In Template studio or WinUI3 Gallery-->
<Page>
<Grid>
<NavigationView PaneDisplayMode="LeftCompact"/>
</Grid>
</Page>
<!--In My App created with Visual Studio default templates-->
<Page>
<Grid>
<NavigationView PaneDisplayMode="LeftCompact"/>
</Grid>
</Page>
In Template studio or WinUI3 Gallery
In My App created with Visual Studio default templates
Even if you modify the ShellPage of an app created with a Template Studio as follows, there is still a difference in appearance.
public sealed partial class ShellPage : Page
{
public ShellPage()
{
InitializeComponent();
}
}
<Page
x:Class="TemplateStudioApp.Views.ShellPage"
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">
<NavigationView PaneDisplayMode="LeftCompact"/>
</Page>

That space at the top is actually the AppTitleBar. This code should create the same look.
App.xaml
<Application
x:Class="WinUI3App.App"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="using:WinUI3App">
<Application.Resources>
<ResourceDictionary>
<ResourceDictionary.MergedDictionaries>
<XamlControlsResources xmlns="using:Microsoft.UI.Xaml.Controls" />
<!-- Other merged dictionaries here -->
</ResourceDictionary.MergedDictionaries>
<!-- Other app resources here -->
<SolidColorBrush
x:Key="WindowCaptionBackground"
Color="Transparent" />
<SolidColorBrush
x:Key="WindowCaptionBackgroundDisabled"
Color="Transparent" />
<Thickness x:Key="NavigationViewContentMargin">0,48,0,0</Thickness>
</ResourceDictionary>
</Application.Resources>
</Application>
MainWindow.xaml.cs
<Window
x:Class="WinUI3App.MainWindow"
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:local="using:WinUI3App"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
mc:Ignorable="d">
<Grid>
<Grid
x:Name="AppTitleBar"
Height="{Binding ElementName=NavigationViewControl, Path=CompactPaneLength}"
VerticalAlignment="Top"
Canvas.ZIndex="1"
IsHitTestVisible="True">
<Image
Width="16"
Height="16"
HorizontalAlignment="Left"
Source="/Assets/WindowIcon.ico" />
<TextBlock
x:Name="AppTitleBarText"
Margin="28,0,0,0"
VerticalAlignment="Center"
Style="{StaticResource CaptionTextBlockStyle}"
TextWrapping="NoWrap" />
</Grid>
<NavigationView
x:Name="NavigationViewControl"
Canvas.ZIndex="0"
DisplayModeChanged="NavigationView_DisplayModeChanged"
ExpandedModeThresholdWidth="1280"
IsBackButtonVisible="Visible"
IsSettingsVisible="True" />
</Grid>
</Window>
MainWindow.xaml.cs
using Microsoft.UI.Xaml;
using Microsoft.UI.Xaml.Controls;
namespace WinUI3App;
public sealed partial class MainWindow : Window
{
public MainWindow()
{
this.InitializeComponent();
ExtendsContentIntoTitleBar = true;
SetTitleBar(this.AppTitleBar);
}
private void NavigationView_DisplayModeChanged(NavigationView sender, NavigationViewDisplayModeChangedEventArgs args)
{
AppTitleBar.Margin = new Thickness()
{
Left = sender.CompactPaneLength * (sender.DisplayMode == NavigationViewDisplayMode.Minimal ? 2 : 1),
Top = AppTitleBar.Margin.Top,
Right = AppTitleBar.Margin.Right,
Bottom = AppTitleBar.Margin.Bottom
};
}
}

<Thickness x:Key="NavigationViewContentGridBorderThickness">1,1,0,0</Thickness>
<CornerRadius x:Key="NavigationViewContentGridCornerRadius">8,0,0,0</CornerRadius>
<Thickness x:Key="NavigationViewContentMargin">0,48,0,0</Thickness>
<Thickness x:Key="NavigationViewHeaderMargin">56,34,0,0</Thickness>
<Thickness x:Key="NavigationViewPageContentMargin">56,24,56,0</Thickness>
In Template Studio, these resources from Styles/Thickness.xaml were the solution.

Binding to UserControl DependencyProperty does not work as expected

I have a header in each page of my Windows Phone 8 Silverlight app. To stop repeating myself I decided to create a simple UserControl witch holds a Grid and a TextBlock. The text of the TextBlock is binded to a DependencyProperty of the UserControl (TitleProperty). See the code at the end.
For the binding to the TitleProperty to work properly I needed to bind the DataContext of the UserControl to itself with the code: DataContext="{Binding RelativeSource={RelativeSource Mode=Self}}".
This works properly when using the control in a page and setting a fixed value or a StaticBinding for the Title property. Ex.:
This works:
<uiuc:SubSectionHeader Title="My fixed title" />
This works to
<uiuc:SubSectionHeader Title="{Binding Source={StaticResource Literals}, Path=Literals.applicationSettings, FallbackValue='[Application Settings]'}" />
But when doing a normal bind it does not work. Ex
<uiuc:SubSectionHeader Title="{Binding Path=UserName'}" />
And that is because the UserControl is looking for the UserName property in its own DataContext (witch is itself), and not in the DataContext of the page.
Question 1 is: Should´t it resolve the binding before passing the value to the Title property?
Question 2: Is it just overwriting the binding in inside the UserControl?
Question 3: How to resolve it? Please don't say create a custom control instead because it sucks
<UserControl x:Class="UI.UserControls.SubSectionHeader"
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:converters="clr-namespace:UI.Converters"
mc:Ignorable="d"
FontFamily="{StaticResource PhoneFontFamilyNormal}"
FontSize="{StaticResource PhoneFontSizeNormal}"
Foreground="{StaticResource PhoneForegroundBrush}"
d:DesignHeight="50"
d:DesignWidth="480"
DataContext="{Binding RelativeSource={RelativeSource Mode=Self}}">
<UserControl.Resources>
<converters:StringCaseConverter x:Name="ToUppercase" />
<converters:BooleanToVisibilityConverter x:Key="BoolToVisibility" />
</UserControl.Resources>
<Grid x:Name="LayoutRoot"
Height="50"
Background="{Binding Source={StaticResource ThemeSetter}, Path=BackgroundColor}">
<TextBlock VerticalAlignment="Center"
Margin="25 0 0 0"
Style="{StaticResource PhoneTextNormalStyle}"
Foreground="White"
Text="{Binding Path=Title, Mode=TwoWay, Converter={StaticResource ToUppercase}, ConverterParameter='upper', FallbackValue='[SUB SECTION TITLE]'}" />
</Grid>
</UserControl>
Code behind:
using System.Windows;
using System.Windows.Controls;
namespace UI.UserControls {
public partial class SubSectionHeader : UserControl {
public SubSectionHeader() {
InitializeComponent();
}
public string Title {
get { return (string)GetValue( TitleProperty ); }
set { SetValue( TitleProperty, value ); }
}
public static readonly DependencyProperty TitleProperty = DependencyProperty.Register(
"Title",
typeof( string ),
typeof( SubSectionHeader ),
new PropertyMetadata( "[SubSection Title]" )
);
}
}

Have you tried setting the DataContext of your UserControl in the code behind? (You would remove the setter in the xaml)
public partial class SubSectionHeader : UserControl {
public SubSectionHeader() {
InitializeComponent();
DataContext = this;
}
Edit: Try setting the design instance of your control inside the xaml. (Leave the code behind statement as well)
<UserControl
x:Class="MyControl
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"
mc:Ignorable="d"
d:DesignHeight="300"
d:DesignWidth="400"
d:DataContext="{d:DesignInstance}">

Two UserControls, one binds, one doesn't

I have two very simple UserControls in a simple WinRT demo project. No Viewmodel--mostly just colored boxes for layout exploration. The first UserControl I created works fine. The second, very similar one, won't bind to any properties--it shows up as blank.
The first UserControl looks like this:
<UserControl
x:Class="Demo.SmallStartTile"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="using:Demo"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
mc:Ignorable="d"
x:Name="SmallStartTileUC"
d:DesignHeight="300"
d:DesignWidth="400">
<Grid x:Name="SmallTileGrid"
Margin="0,0,8,8"
Background="{Binding Background, ElementName=SmallStartTileUC}"
>
<Rectangle
Stroke="{Binding BorderBrush, ElementName=SmallStartTileUC}"
Grid.RowSpan="2"
/>
<TextBlock x:Name="SmallTileTitle"
Text="{Binding TileText, ElementName=SmallStartTileUC}"
Style="{StaticResource SmallTileHeader}"/>
<Path x:Name="IconPath"
Style="{StaticResource SmallTileIcon}"
Data="{Binding TileIconPathData, ElementName=SmallStartTileUC}" />
</Grid>
</UserControl>
namespace Demo
{
public sealed partial class SmallStartTile : UserControl
{
public static DependencyProperty TileTextProperty = DependencyProperty.Register("TileText", typeof(string), typeof(SmallStartTile), new PropertyMetadata("tile content"));
public string TileText
{
get { return (string)GetValue(TileTextProperty); }
set { SetValue(TileTextProperty, value); }
}
public static DependencyProperty TileIconPathDataProperty = DependencyProperty.Register("TileIconPathData", typeof(string), typeof(SmallStartTile), new PropertyMetadata("F0"));
public string TileIconPathData
{
get { return (string)GetValue(TileIconPathDataProperty); }
set { SetValue(TileIconPathDataProperty, value); }
}
public SmallStartTile()
{
this.InitializeComponent();
}
}
}
And the second one, which I made just like the first one by clicking Add New Item and picking UserControl in Blend:
<UserControl
x:Class="Demo.SmallMediaTile"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="using:Demo"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
mc:Ignorable="d"
x:Name="SmallMediaTileUC"
d:DesignHeight="300"
d:DesignWidth="400">
<Grid
Margin="0,0,8,8"
Background="{Binding Background, ElementName=SmallMediaTileUC}"
>
<Grid.RowDefinitions>
<RowDefinition/>
<RowDefinition Height="Auto"/>
</Grid.RowDefinitions>
<Rectangle
Stroke="{Binding BorderBrush, ElementName=SmallMediaTileUC}"
Grid.RowSpan="2"
/>
<Viewbox
Margin="30"
Child="{Binding Content, ElementName=SmallMediaTileUC}">
</Viewbox>
<TextBlock
Grid.Row="1"
Text="{Binding SourceText, ElementName=SmallMediaTileUC}"
Style="{StaticResource SmallMusicTileHeader}"/>
</Grid>
</UserControl>
namespace Demo
{
public sealed partial class SmallMediaTile : UserControl
{
public static DependencyProperty SourceTextProperty = DependencyProperty.Register("SourceText", typeof(string), typeof(SmallMediaTile), new PropertyMetadata("source"));
public string SourceText
{
get { return (string)GetValue(SourceTextProperty); }
set { SetValue(SourceTextProperty, value); }
}
public SmallMediaTile()
{
this.InitializeComponent();
}
}
}
I use the UserControl in the main Page like this:
<local:SmallMediaTile x:Name="Source1Tile"
Grid.Column="0" Grid.Row="0"
SourceText="Radio"
Background="Blue"
BorderBrush="Red">
<local:SmallMediaTile.Content>
<Canvas x:Name="radio_icon" Height="68" Width="34">
<Path Data="F1M299.6182,396.2988C299.6182,389.7208,297.0722,383.5548,292.4572,378.8398L288.6162,382.6758C292.2022,386.3718,294.1842,391.1778,294.1842,396.2988C294.1842,401.4238,292.2022,406.2368,288.6162,409.9328L292.4572,413.7738C297.0722,409.0538,299.6182,402.8808,299.6182,396.2988" Fill="White" Height="34.934" Canvas.Left="0" Stretch="Fill" Canvas.Top="16.501" Width="11.002"/>
<Path Data="F1M311.1738,396.2988C311.1738,386.6278,307.4348,377.5528,300.6788,370.6208L296.8258,374.4618C302.5658,380.3698,305.7398,388.0798,305.7398,396.2988C305.7398,404.5218,302.5658,412.2298,296.8258,418.1428L300.6788,421.9898C307.4348,415.0498,311.1738,405.9718,311.1738,396.2988" Fill="White" Height="51.369" Canvas.Left="8.21" Stretch="Fill" Canvas.Top="8.282" Width="14.348"/>
<Path Data="F1M322.7578,396.2988C322.7578,383.5298,317.8508,371.5348,308.9638,362.3388L305.1168,366.1748C312.9758,374.3538,317.3338,384.9778,317.3338,396.2988C317.3338,407.6208,312.9758,418.2488,305.1168,426.4268L308.9638,430.2748C317.8508,421.0698,322.7578,409.0798,322.7578,396.2988" Fill="White" Height="67.936" Canvas.Left="16.501" Stretch="Fill" Canvas.Top="0" Width="17.641"/>
</Canvas>
</local:SmallMediaTile.Content>
</local:SmallMediaTile>
The first one picks up all the properties and displays like I expect, but the second one only picks up the Viewbox content. I've looked through SO and been googling but can't figure out what the problem is. Sorry if this is longwinded.

Your root Grid is set as the Content of the UserControl while the Viewbox you have is trying to bind its Child property to the Content of the UserControl that is its ascendant. That is not allowed since the root Grid is already a parent of the UserControl and XAML controls can only exist in one place in the UI.

As noted, the problem is the UserControl's content can only be set once. When I bind the Viewbox Content to the UserControl content, the existing XAML is replaced. So, a blank box but for what I'm passing in. I guess to do what I had hoped, I'd need to make a custom control. Thanks for the help!

XmlDataProvider and XPath bindings don't allow default namespace of XML data?

I am struggling to work out how to use default namespaces with XmlDataProvider and XPath bindings.
There's an ugly answer using local-name <Binding XPath="*[local-name()='Name']" /> but that is not acceptable to the client who wants this XAML to be highly maintainable.
The fallback is to force them to use non-default namespaces in the report XML but that is an undesirable solution.
The XML report file looks like the following. It will only work if I remove xmlns="http://www.acme.com/xml/schemas/report so there is no default namespace.
<?xml version="1.0" encoding="utf-8"?>
<?xml-stylesheet type='text/xsl' href='PreviewReportImages.xsl'?>
<Report xsl:schemaLocation="http://www.acme.com/xml/schemas/report BlahReport.xsd" xmlns:xsl="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://www.acme.com/xml/schemas/report">
<Service>Muncher</Service>
<Analysis>
<Date>27 Apr 2010</Date>
<Time>0:09</Time>
<Authoriser>Service Centre Manager</Authoriser>
Which I am presenting in a window with XAML:
<Window x:Class="AcmeTest.ReportPreview"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="ReportPreview" Height="300" Width="300" >
<Window.Resources>
<XmlDataProvider x:Key="Data"/>
</Window.Resources>
<StackPanel Orientation="Vertical" DataContext="{Binding Source={StaticResource Data}, XPath=Report}">
<TextBlock Text="{Binding XPath=Service}"/>
</StackPanel>
</Window>
with code-behind used to load an XmlDocument into the XmlDataProvider (seems the only way to have loading from a file or object varying at runtime).
public partial class ReportPreview : Window
{
private void InitXmlProvider(XmlDocument doc)
{
XmlDataProvider xd = (XmlDataProvider)Resources["Data"];
xd.Document = doc;
}
public ReportPreview(XmlDocument doc)
{
InitializeComponent();
InitXmlProvider(doc);
}
public ReportPreview(String reportPath)
{
InitializeComponent();
var doc = new XmlDocument();
doc.Load(reportPath);
InitXmlProvider(doc);
}
}

I hadn't realised that I don't need to add a prefix to the client XML data, just use a prefix in my XPath expressions that maps to the same URI as the default namespace (obvious when I slept on it!).
So, the fix was to add a namespace mapping as shown here, note the use of the r: prefix on the elements.
<Window x:Class="AcmeTest.ReportPreview"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="ReportPreview" Height="300" Width="300" >
<Window.Resources>
<XmlDataProvider x:Key="Data">
<XmlDataProvider.XmlNamespaceManager>
<XmlNamespaceMappingCollection>
<XmlNamespaceMapping
Uri="http://www.acme.com/xml/schemas/report"
Prefix="r" />
</XmlNamespaceMappingCollection>
</XmlDataProvider.XmlNamespaceManager>
</XmlDataProvider>
</Window.Resources>
<StackPanel Orientation="Vertical" DataContext="{Binding Source={StaticResource Data}, XPath=Report}">
<TextBlock Text="{Binding XPath=r:Service}"/>
<TextBlock Text=" "/>
<TextBlock Text="{Binding XPath=r:Name/r:Last}"/>
</StackPanel>
</Window>