Binding ListBox to List in Silverilght not working - c#

All,
I have what i think is the simplest example possible of data binding in silverlight... but clearly even that is too complicated for me :)
The XAML:
<UserControl x:Class="SilverlightApplication1.MainPage"
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:DesignWidth="640" d:DesignHeight="480">
<ListBox x:Name="rblSessions">
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding SessionTitle}" Foreground="Black" FontSize="30" />
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
The code behind:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;
namespace SilverlightApplication1
{
public partial class MainPage : UserControl
{
public MainPage()
{
InitializeComponent();
List<Sessions> theSessions = makeSessions();
rblSessions.ItemsSource = theSessions;
rblSessions.DataContext = theSessions;
}
public List<Sessions> makeSessions()
{
List<Sessions> theReturn = new List<Sessions>();
for (int i = 0; i < 20; i++)
{
Sessions s = new Sessions() { SessionID = i, SessionTitle = string.Format("title{0}", i) };
theReturn.Add(s);
}
return theReturn;
}
}
public class Sessions
{
public int SessionID;
public string SessionTitle;
}
}
When I run the app, I get a listbox with 20 elements in it, but each element is empty, and only about 5 pixels tall (though I set FontSize to "30")
What am I doing wrong? Help please and thanks
/jonathan

You must make your Session class members into properties in order to use them in a binding. This should fix it:
public class Sessions
{
public int SessionID { get; set; }
public string SessionTitle { get; set; }
}

Related

How to change field to original value using a "reset" button in wpf

I have a class that has several properties, one of which is editable, another of which is calculated based on the editable value. I want to initialize the editable value with something and allow the user to change it however they wish. However, I also want to have a reset button that puts the original value back into the textbox. I have a third variable that stores the value of the original number. However, I am not sure how I am supposed to access the object when the reset button is clicked to put the value back into the textbox. I've put the relevant code below (if I shouldn't be posting everything please let me know, still new to stackoverflow how-to):
Main Window
C#
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
using HDR_BED_Calc_local.Testers;
using HDR_BED_Calc_local.Helpers;
namespace HDR_BED_Calc_local
{
/// <summary>
/// Interaction logic for MainWindow.xaml
/// </summary>
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
//var window = new MainWindow();
this.DataContext = new fraction_doses(800, 700, 900, 800, 900, 1, 3);
}
}
}
XAML
<Window x:Class="HDR_BED_Calc_local.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:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:local="clr-namespace:HDR_BED_Calc_local"
xmlns:uctesters="clr-namespace:HDR_BED_Calc_local.Testers"
mc:Ignorable="d"
Title="MainWindow" Height="450" Width="800">
<Grid>
<uctesters:fx_tester x:Name="fxtester_UC"/>
</Grid>
</Window>
Custom user control
C#
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
using HDR_BED_Calc_local.Helpers;
namespace HDR_BED_Calc_local.Testers
{
/// <summary>
/// Interaction logic for fx_tester.xaml
/// </summary>
public partial class fx_tester : UserControl
{
public fx_tester()
{
InitializeComponent();
}
private void Button_Click(object sender, RoutedEventArgs e)
{
// What do I put here??
}
}
}
XAML
<UserControl x:Class="HDR_BED_Calc_local.Testers.fx_tester"
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:local="clr-namespace:HDR_BED_Calc_local.Testers"
mc:Ignorable="d"
d:DesignHeight="450" d:DesignWidth="800" Background="White">
<StackPanel HorizontalAlignment="Center">
<StackPanel Orientation="Horizontal">
<TextBlock xml:space="preserve">Fraction: </TextBlock>
<TextBlock Text="{Binding Path=fraction_number}"></TextBlock>
</StackPanel>
<StackPanel Orientation="Horizontal">
<TextBlock xml:space="preserve">Current Dose: </TextBlock>
<TextBox x:Name="curr_fx_tb" Text="{Binding Path=editable_fraction_dose, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"></TextBox>
</StackPanel>
<StackPanel Orientation="Horizontal">
<TextBlock xml:space="preserve">EQD2: </TextBlock>
<TextBlock Text="{Binding Path=this_fx_brachy_EQD2, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"/>
</StackPanel>
<Button Content="Reset" Click="Button_Click"/>
</StackPanel>
</UserControl>
Helper function with class
C#
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.ComponentModel;
using System.Runtime.CompilerServices;
namespace HDR_BED_Calc_local.Helpers
{
internal class fraction_doses : INotifyPropertyChanged
{
public int fraction_number { get; set; }
public double alpha_beta { get; }
private double _editable_fraction_dose;
public double editable_fraction_dose
{
get { return _editable_fraction_dose; }
set
{
_editable_fraction_dose = value;
calc_EQD2();
this.OnPropertyChanged("editable_fraction_dose");
}
}
public double actual_fraction_dose { get; }
public double pear_plan_dose { get; }
public double IMRT_plan_dose { get; }
public double max_dose_limit { get; }
public double preferred_dose_limit { get; }
private double _this_fx_brachy_EQD2;
public double this_fx_brachy_EQD2
{
get { return this._this_fx_brachy_EQD2; }
set
{
this._this_fx_brachy_EQD2 = value;
this.OnPropertyChanged("this_fx_brachy_EQD2");
}
}
public event PropertyChangedEventHandler PropertyChanged;
public fraction_doses(double current_dose, double pear_dose, double IMRT_dose, double max_dose_limit, double preferred_dose_limit, int fraction_number, int alpha_beta)
{
this.alpha_beta = alpha_beta;
this.actual_fraction_dose = current_dose;
this.editable_fraction_dose = current_dose;
this.pear_plan_dose = pear_dose;
this.IMRT_plan_dose = IMRT_dose;
this.max_dose_limit = max_dose_limit;
this.preferred_dose_limit = preferred_dose_limit;
this.fraction_number = fraction_number;
}
public void calc_EQD2()
{
// EQD2 is always reported in Gray even though we will be reporting cGy
double dose_Gy = this.editable_fraction_dose/100;
this.this_fx_brachy_EQD2 = Math.Round(1 * dose_Gy * (1+ dose_Gy / alpha_beta)/(1+2/alpha_beta), 2);
}
public void OnPropertyChanged([CallerMemberName] string propertyName = null)
{
if (PropertyChanged != null)
{
this.PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
}
}
You can try the following:
private void Button_Click(object sender, RoutedEventArgs e)
{
// What do I put here??
var dc = (fraction_doses ) this.DataContext:
if(dc!=null)
dc.Clear();
}
in your fraction_doses class add the method that clears the properties
public void Clear(){
this.MyProperty = MY_DEFAULT_VALUE;
//clear other properties..
}

Binds not updating when messaging between view models using MVVMLight.Messaging

I'm trying to set the visibility of tab items in a viewmodel from another viewmodel.
I know the binds are correct for I can set the properties (set to false) in the constructor of the new model and they appear / disappear as I wish (setting some to true).
I know that the messenger is working for I can register to wait for a message in the constructor and send a message in the same constructor which get handled by my message callback and the binds update correctly (I can see tabs that were initially set to false).
I know this is not a race condition because I have set Console write lines and see the order in which each line is called. Create Window -> Register Message callback -> Create message and send.
Sending a message from the first ViewModel to the 2nd my callback in the new viewmodel is called and changes the properties but the view does not change (what is hidden stays hidden).
Method from original viewmodel.
private void GenerateWindowedReport()
{
Console.WriteLine("Executing View Windowed Report");
Window ReportWindow = new ReportWindow();
var msg = new TabVisibility() {
SuitesReportVisible = IncludeReportSuites,
TenantRankingsVisible = IncludeReportTenantRanking,
IndustryReportVisible = IncludeReportIndustry,
SubmarketBreakdownVisible = IncludeReportSubmarket
};
Messenger.Default.Send<TabVisibility>(msg);
ReportWindow.Show();
}
Class TabVisibility
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace Analytics_Module.Messages
{
class TabVisibility
{
public bool SuitesReportVisible { get; set; }
public bool TenantRankingsVisible { get; set; }
public bool IndustryReportVisible { get; set; }
public bool SubmarketBreakdownVisible { get; set; }
}
}
New View (Is contained in the new window created in the first method)
<UserControl x:Class="Analytics_Module.Views.TabsReportView"
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:local="clr-namespace:Analytics_Module.Views"
xmlns:viewModel="clr-namespace:Analytics_Module.ViewModels"
mc:Ignorable="d"
d:DesignHeight="450" d:DesignWidth="800">
<UserControl.Resources>
<BooleanToVisibilityConverter x:Key="BooleanToVisibilityConverter"/>
<viewModel:TabsReportViewModel x:Key="vmTabsReport" />
</UserControl.Resources>
<Grid DataContext="{Binding Source={StaticResource vmTabsReport}}">
<TabControl SelectedIndex="{Binding SelectedReportIndex}" >
<TabItem Header="Search Parameteres" >
<ContentControl Margin="0,10,0,5" Name="TabContentReportSearchParameters" />
</TabItem>
<TabItem Header="Suites Report"
Visibility="{Binding VisibilitySuitesReportTab,
Converter={StaticResource BooleanToVisibilityConverter}}"
IsSelected="{Binding VisibilitySuitesReportTab}">
<ContentControl Name="TabContentReportSuites" />
</TabItem>
<TabItem Header="Tenant Rankings" Visibility="{Binding VisibilityTenantRankingsTab,
Converter={StaticResource BooleanToVisibilityConverter}}">
<ContentControl Margin="0,10,0,5" Name="TabContentReportTenantRankings" />
</TabItem>
<TabItem Header="Industry Breakdown" Visibility="{Binding VisibilityIndustryBreakdownTab,
Converter={StaticResource BooleanToVisibilityConverter}}">
<ContentControl Name="TabContentReportIndustryBreakdown" />
</TabItem>
<TabItem Header="Submarket Breakdown" Visibility="{Binding VisibilitySubmarketBreakdownTab,
Converter={StaticResource BooleanToVisibilityConverter}}">
<ContentControl Name="TabContentReportSubmarketBreakdown" />
</TabItem>
</TabControl>
</Grid>
</UserControl>
Code behind of new view
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
namespace Analytics_Module.Views
{
/// <summary>
/// Interaction logic for TabsReportView.xaml
/// </summary>
public partial class TabsReportView : UserControl
{
public TabsReportView()
{
InitializeComponent();
}
}
}
ViewModel giving me issues:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Analytics_Module.Messages;
using Analytics_Module.Utillity;
using MVVMLight.Messaging;
namespace Analytics_Module.ViewModels
{
class TabsReportViewModel : BaseViewModel
{
protected static class TabIndexConstants
{
public const int SearchParameters = 0;
public const int SuitesReport = 1;
public const int TenantRankings = 2;
public const int IndustryBreakdown = 3;
public const int SubmarketBreakdwown = 4;
}
public TabsReportViewModel() : base()
{
Console.WriteLine("TabsreportVM Constructor");
SelectedReportIndex = TabIndexConstants.SearchParameters;
VisibilitySuitesReportTab = false;
VisibilityTenantRankingsTab = false;
VisibilityIndustryBreakdownTab = false;
VisibilitySubmarketBreakdownTab = false;
Messenger.Default.Register<TabVisibility>
(this, (msgTabVisibility) => SetTabVisibility(msgTabVisibility));
Console.WriteLine("Message Registered");
TabVisibility t = new TabVisibility();
t.IndustryReportVisible = true;
t.SubmarketBreakdownVisible = true;
t.SuitesReportVisible = true;
t.TenantRankingsVisible = true;
//SetTabVisibility(t);
//Messenger.Default.Send<TabVisibility>(t);
}
public void SetTabVisibility(TabVisibility msgTabVisibility)
{
Console.WriteLine("Tabs Set Visiblity Callback");
VisibilitySuitesReportTab = (bool) msgTabVisibility.SuitesReportVisible;
VisibilityTenantRankingsTab = (bool) msgTabVisibility.TenantRankingsVisible;
VisibilityIndustryBreakdownTab = (bool) msgTabVisibility.IndustryReportVisible;
VisibilitySubmarketBreakdownTab = (bool)msgTabVisibility.SubmarketBreakdownVisible;
}
public int SelectedReportIndex { get; set; }
public bool VisibilitySuitesReportTab { get; set; }
public bool VisibilityTenantRankingsTab { get; set; }
public bool VisibilityIndustryBreakdownTab { get; set; }
public bool VisibilitySubmarketBreakdownTab { get; set; }
}
}
I found a workaround but this seems more like a hack. All I had to do was to manually trigger the OnPropertyChanged for each property.
public void SetTabVisibility(MessageTabVisibility msgTabVisibility)
{
Console.WriteLine("Tabs Set Visiblity Callback");
VisibilitySuitesReportTab = (bool) msgTabVisibility.SuitesReportVisible;
VisibilityTenantRankingsTab = (bool) msgTabVisibility.TenantRankingsVisible;
VisibilityIndustryBreakdownTab = (bool) msgTabVisibility.IndustryReportVisible;
VisibilitySubmarketBreakdownTab = (bool)msgTabVisibility.SubmarketBreakdownVisible;
Messenger.Default.Unregister<MessageTabVisibility>(this);
Console.WriteLine("Refresh");
OnPropertyChanged("VisibilitySuitesReportTab");
OnPropertyChanged("VisibilityTenantRankingsTab");
OnPropertyChanged("VisibilityIndustryBreakdownTab");
OnPropertyChanged("VisibilitySubmarketBreakdownTab");
}

How to change Text property with ICommand C# XAML

I make a simple weather app. And now i want to change it.
I want to implement a command to a button, and when is pressed, a TextBlock will update with weather info but i can't acces property of TextBlock.
Here is the Command class from Models:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Input;
namespace RemakeWindowsWeather.Models
{
public class Command : ICommand
{
public event EventHandler CanExecuteChanged;
Func<object, bool> canExecuteMethod;
Action<object> executeMethod;
public Command(Func<object, bool> canExecuteMethod, Action<object> executeMethod)
{
this.canExecuteMethod = canExecuteMethod;
this.executeMethod = executeMethod;
}
public bool CanExecute(object parameter)
{
return canExecuteMethod(parameter);
}
public void Execute(object parameter)
{
executeMethod(parameter);
}
}
}
Here is the class from ViewModels where i want to change the property of TextBlock:
using RemakeWindowsWeather.Models;
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace RemakeWindowsWeather.ViewModels
{
public class CommandViewModel
{
Command ShowWeather { get; set; }
public CommandViewModel()
{
ShowWeather = new Command(canExecuteMethod, executeMethod);
}
private bool canExecuteMethod(object parameter)
{
return true;
}
private async void executeMethod(object parameter)
{
var pos = await LocationManager.GetLocation();
var lat = pos.Coordinate.Latitude;
var lon = pos.Coordinate.Longitude;
var weather = await WeatherProxyMap.GetWeather(lon, lat);
//HERE.. not working
WeatherCondition.Text = weather.main.temp + " " + weather.name;
}
}
}
Here is the XAML:
<Page
x:Class="RemakeWindowsWeather.MainPage"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="using:RemakeWindowsWeather"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
mc:Ignorable="d"
x:Name="MyPage">
<Grid Background="{ThemeResource ApplicationPageBackgroundThemeBrush}">
<StackPanel>
<Button Height="30"
Width="120"
Click="Button_Click"
Content="Get Weather"/>
<TextBlock Name="WeatherCondition"
Margin="0,20,0,20"/>
<TextBox Name="CitySearch"
PlaceholderText="Search for weather.."
Margin="0,20,0,20"/>
<Button Width="120"
Height="30"
Click="Button_Click_1"
Content="Get Weather"/>
<TextBlock Name="CityNameTxtBlock"/>
</StackPanel>
</Grid>
You need to bind your command from the viewmodel in xaml, instead using event handlers in the view.
<Button Width="120"
Height="30"
Command="{Binding ShowWeather}"
Content="Get Weather"/>
Also the command should be public and you need a text property
public Command ShowWeather { get; set; }
public string WeatherText { get; set; }
Then you need to bind the text from the viewmodel in the view.
<TextBlock Name="WeatherCondition" Margin="0,20,0,20" Text="{Binding WeatherText}"/>
also you would need to implement INotifyPropertyChanged in the viewmodel and call it when you modify the text.
WeatherText= weather.main.temp + " " + weather.name;
this.RaisePropertyChanged("WeatherText");
This pretty much basic MVVM which you can read about from here.

ComboBox printing the Object Type

i'm trying to learn WPF and on top of that the MVVM style of doing things.
I have a simple practice app in which i would like to display codes in a combo box.
My Code
using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
namespace SteamCodes
{
/// <summary>
/// Interaction logic for MainWindow.xaml
/// </summary>
public partial class MainWindow : Window
{
private ObservableCollection<Codes> codes;
public MainWindow()
{
InitializeComponent();
codes = new ObservableCollection<Codes>()
{
new Codes() {CodeID = "1", Code="CODETEXT"}
};
steamCode.ItemsSource = codes.ToString();
}
}
public class Codes
{
public string CodeID { get; set; }
public string Code { get; set; }
}
}
My XAML
<Window x:Class="SteamCodes.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:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:local="clr-namespace:SteamCodes"
mc:Ignorable="d"
Title="MainWindow" Height="350" Width="525">
<Grid>
<ComboBox x:Name="steamCode" ItemsSource="{Binding Source = Codes}" HorizontalAlignment="Left" Height="43" Margin="122,37,0,0" VerticalAlignment="Top" Width="259"/>
</Grid>
</Window>
At the moment my Combo box is Pulling through as each option in the ComboBox is a letter from the line 'System.Collections.Objectmodel.ObservableCollection`1[SteamCodes.Codes]'
Everyone of those letters is a different drop down option in the combo box.
Any Ideas where i have gone wrong.
Your ComboBox ItemSource must be a collection of items, not a string:
steamCode.ItemsSource = codes;
You also have to specify which property of your item must be considered as value to be shown in combobox by setting DisplayMemberPath property:
steamCode.DisplayMemberPath = "Code";
To specify which property of bound objects will be used as actual selected value you have to use SelectedValuePath property:
steamCode.SelectedValuePath = "CodeID";
The MVVM approach is this:
public class ViewModel
{
public ObservableCollection<Codes> Codes { get; }
= new ObservableCollection<Codes>();
}
The MainWindow constructor:
public MainWindow()
{
InitializeComponent();
var viewModel = new ViewModel();
viewModel.Codes.Add(new Codes { CodeID = "1", Code = "CODETEXT" });
DataContext = viewModel;
}
The XAML:
<ComboBox ItemsSource="{Binding Codes}" DisplayMemberPath="Code" .../>

Binding to User Control Properties in an Items Control

Can someone tell me why the way I am binding data here does not work? I was able to do this fine with using a GridView. I am not sure why the data is not being passed to the user control here, in addition it compiles fine and shows the user controls with there default text
Main.xaml.cs:
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using Windows.Foundation;
using Windows.Foundation.Collections;
using Windows.UI.Xaml;
using Windows.UI.Xaml.Controls;
using Windows.UI.Xaml.Controls.Primitives;
using Windows.UI.Xaml.Data;
using Windows.UI.Xaml.Input;
using Windows.UI.Xaml.Media;
using Windows.UI.Xaml.Media.Imaging;
using Windows.UI.Xaml.Navigation;
// The Blank Page item template is documented at http://go.microsoft.com/fwlink/?LinkId=234238
namespace ItemsControlSample
{
/// <summary>
/// An empty page that can be used on its own or navigated to within a Frame.
/// </summary>
public sealed partial class MainPage : Page
{
public MainPage()
{
this.InitializeComponent();
}
/// <summary>
/// Invoked when this page is about to be displayed in a Frame.
/// </summary>
/// <param name="e">Event data that describes how this page was reached. The Parameter
/// property is typically used to configure the page.</param>
protected override void OnNavigatedTo(NavigationEventArgs e)
{
PopulateData();
}
public class someKindaOfDataHolder
{
public string Text1;
public string Text2;
}
private void PopulateData()
{
List<someKindaOfDataHolder> dataAndStuff = new List<someKindaOfDataHolder>();
for (int i = 0; i < 5; ++i)
{
dataAndStuff.Add(new someKindaOfDataHolder()
{
Text1 = "data spot 1: " + i.ToString(),
Text2 = "data spot 2: " + (i + 2).ToString()
});
}
ListOfAUserControls.ItemsSource = dataAndStuff;
}
}
}
Main.xaml
<Page
x:Class="ItemsControlSample.MainPage"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="using:ItemsControlSample"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
mc:Ignorable="d">
<Grid Background="{StaticResource ApplicationPageBackgroundThemeBrush}">
<ScrollViewer>
<ItemsControl x:Name="ListOfAUserControls" ItemsSource="{Binding}">
<ItemsControl.ItemTemplate>
<DataTemplate>
<local:CustomUserControl DynamicText1Text="{Binding Text1}" DynamicText2Text="{Binding Text2}" Margin="0,0,10,0"/>
</DataTemplate>
</ItemsControl.ItemTemplate>
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<StackPanel Orientation="Horizontal" HorizontalAlignment="Left" VerticalAlignment="Top" Margin="100,46,-50,0"/>
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
</ItemsControl>
</ScrollViewer>
</Grid>
</Page>
CustomUserControl.xaml.cs:
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using Windows.Foundation;
using Windows.Foundation.Collections;
using Windows.UI.Xaml;
using Windows.UI.Xaml.Controls;
using Windows.UI.Xaml.Controls.Primitives;
using Windows.UI.Xaml.Data;
using Windows.UI.Xaml.Input;
using Windows.UI.Xaml.Media;
using Windows.UI.Xaml.Navigation;
// The User Control item template is documented at http://go.microsoft.com/fwlink/?LinkId=234236
namespace ItemsControlSample
{
public sealed partial class CustomUserControl : UserControl
{
public static readonly DependencyProperty DynamicText1Property =
DependencyProperty.Register("DynamicText1Text", typeof(string), typeof(CustomUserControl), new PropertyMetadata(null, OnDynamicText1PropertyChanged));
public string DynamicText1Text
{
get { return (string)GetValue(DynamicText1Property); }
set { SetValue(DynamicText1Property, value); }
}
public static readonly DependencyProperty DynamicText2Property =
DependencyProperty.Register("DynamicText2Text", typeof(string), typeof(CustomUserControl), new PropertyMetadata(null, OnDynamicText2PropertyChanged));
public string DynamicText2Text
{
get { return (string)GetValue(DynamicText2Property); }
set { SetValue(DynamicText2Property, value); }
}
public CustomUserControl()
{
this.InitializeComponent();
}
private static void OnDynamicText1PropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
var obj = d as CustomUserControl;
obj.DynamicText1.Text = e.NewValue.ToString();
}
private static void OnDynamicText2PropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
var obj = d as CustomUserControl;
obj.DynamicText2.Text = e.NewValue.ToString();
}
}
}
CustomUserControl.xaml:
<UserControl
x:Class="ItemsControlSample.CustomUserControl"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="using:ItemsControlSample"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
mc:Ignorable="d"
d:DesignHeight="800"
d:DesignWidth="800">
<Grid Background="Blue">
<Grid.RowDefinitions>
<RowDefinition Height="6*"/>
<RowDefinition Height="2*"/>
</Grid.RowDefinitions>
<Image Source="ms-appx:///Assets/MSIcon.png" />
<StackPanel Grid.Row="1" Margin="25">
<TextBlock Text="Obay" FontSize="45" />
<TextBlock x:Name="DynamicText1" Text="DynamicText1" FontSize="35" />
<TextBlock x:Name="DynamicText2" Text="DynamicText2" FontSize="35" />
</StackPanel>
</Grid>
</UserControl>
Thanks!
You need to set the DataContext somewhere. Without it - your bindings have no context and they fail (look at the Output window in VS when debugging Debug builds to see binding errors). You are setting ItemsSource="{Binding}" where the binding has no context.
Then again - you are overriding the ItemsSource elsewhere with your "ListOfAUserControls.ItemsSource = dataAndStuff;" call, so that is likely not the issue causing your problem in the end. The DataContext of an item in an ItemsControl should be set automatically to an item in the ItemsSource collection.
Another problem that might block you there is that someKindaOfDataHolder.Text1 in your case is a field and it should be a property to work with bindings - try this instead:
public string Text1 { get; set; }

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