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Thursday, June 12, 2014

MultiBinding WPF Example

WPF > Windows > Data > MultiBinding

Represents a collection of Binding objects attached to a single binding target property.

Example



XAML


<Window x:Class="WpfApplication4.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="MainWindow" Height="350" Width="525"
        xmlns:local="clr-namespace:WpfApplication4">
    <Window.Resources>
        <local:NameConvertor x:Key="nameConvertor"></local:NameConvertor>
    </Window.Resources>

    <Grid>
        <Grid>
            <TextBlock HorizontalAlignment="Left" Margin="20,30,0,0" TextWrapping="Wrap" Text="First Name" VerticalAlignment="Top"/>
            <TextBox x:Name="txtFirstName" HorizontalAlignment="Left" Height="23" Margin="86,27,0,0" TextWrapping="Wrap" VerticalAlignment="Top" Width="120"/>
            <TextBlock HorizontalAlignment="Left" Margin="20,68,0,0" TextWrapping="Wrap" Text="Last Name" VerticalAlignment="Top"/>
            <TextBox x:Name="txtLastName" HorizontalAlignment="Left" Height="23" Margin="86,65,0,0" TextWrapping="Wrap" VerticalAlignment="Top" Width="120"/>
            <TextBlock HorizontalAlignment="Left" Margin="20,110,0,0" TextWrapping="Wrap" Text="Full Name" VerticalAlignment="Top"/>
            <TextBox x:Name="txtLastName_Copy" HorizontalAlignment="Left" Height="23" Margin="86,107,0,0" TextWrapping="Wrap" VerticalAlignment="Top" Width="267">
                <TextBox.Text>
                    <MultiBinding Converter="{StaticResource nameConvertor}" UpdateSourceTrigger="PropertyChanged">
                        <Binding ElementName="txtFirstName" Path="Text" />
                        <Binding ElementName="txtLastName" Path="Text" />
                    </MultiBinding>
                </TextBox.Text>
            </TextBox>
        </Grid>
    </Grid>

</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;

namespace WpfApplication4
{
    public class NameConvertor : IMultiValueConverter
    {
        public object Convert(object[] values, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
            return String.Concat(values[0], ",", values[1]);
        }

        public object[] ConvertBack(object value, Type[] targetTypes, object parameter, System.Globalization.CultureInfo culture)
        {
            return (value as string).Split(',');
        }
    }

    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
        }
    }
}



Data Namespace WPF

WPF > Windows > Data Namespace

Contains classes used for binding properties to data sources




Tuesday, June 3, 2014

ComboBoxItem WPF Example

WPF > Controls  > ContentControl > ComboBoxItem 

ComboBoxItem represent an item in a ComboBox.


Example:

XAML


<Window x:Class="WpfApplication3.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="MainWindow" Height="350" Width="525">
    <Grid>
        <ComboBox x:Name="cbo" HorizontalAlignment="Left" VerticalAlignment="Top" Width="120" SelectionChanged="ComboBox_SelectionChanged">
            <ComboBoxItem>Option1</ComboBoxItem>
            <ComboBoxItem>Option2</ComboBoxItem>
        </ComboBox>

    </Grid>
</Window>

C#
private void ComboBox_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
  string value = ((ComboBoxItem)cbo.SelectedItem).Content.ToString();
}


WPF Read RSS feed and bind to DataGrid

WPF > SyndicationFeed > Read RSS feed

Read RSS feed and bind to DataGrid



XAML


<Window x:Class="Feed.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="Rss Feed" Height="670" Width="737" Loaded="Window_Loaded">
    <Grid>
        <DataGrid ItemsSource="{Binding RssFeedList}"  AutoGenerateColumns="False" IsReadOnly="True">
            <DataGrid.Columns>
                <DataGridTextColumn Header="Title" Binding="{Binding Title}"/>
            </DataGrid.Columns>
        </DataGrid>
      
    </Grid>
</Window>


c#

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 Feed
{
    public class RssFeed
    {
        public string Title { get; set; }
    }
      
      
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        public ObservableCollection<RssFeed> RssFeedList { get; set; }
        public MainWindow()
        {
            InitializeComponent();
        }

        private void Window_Loaded(object sender, RoutedEventArgs e)
        {
            string feedUrl = "http://rss.cnn.com/rss/cnn_latest.rss";
            System.Xml.XmlReader reader = System.Xml.XmlReader.Create(feedUrl);

            System.ServiceModel.Syndication.SyndicationFeed feed = System.ServiceModel.Syndication.SyndicationFeed.Load(reader);
            RssFeedList = new ObservableCollection<RssFeed>();
            foreach (var item in feed.Items)
            {
                RssFeed rf = new RssFeed();
                rf.Title = item.Title.Text.ToString();
                RssFeedList.Add(rf);
            }
            this.DataContext = this;
        }
    }
}



Wednesday, May 21, 2014

Get tree visual elements WPF

WPFWindows > MediaVisualTreeHelper 

VisualTreeHelper provides methods that perform

tasks involving nodes in a visual tree.


Example:

Get tree visual elements for user control


FrameworkElement fe = (FrameworkElement)YourControl;
for (int i = 0; i < VisualTreeHelper.GetChildrenCount(fe); i++)
{
   Grid childVisual = (Grid)VisualTreeHelper.GetChild(fe, i);
   childVisual.Width = sp.ActualWidth;
}

Monday, May 19, 2014

WPF Converter Example

WPF > Data > Converters

Converters changes data from one type to another and apply custom logic to binding.
Implementation : create a class that implements the IvalueConverter.

Example:


XAML:

<Window x:Class="WpfApplication2.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:local="clr-namespace:WpfApplication2"
        Title="MainWindow" Height="350" Width="525">
    <Window.Resources>
        <local:YesNoConverter x:Key="YesNoConverter" />
    </Window.Resources>
    <StackPanel Margin="5">
        <CheckBox x:Name="chk" IsChecked="{Binding ElementName=txtYesNo, Path=Text, Converter={StaticResource YesNoConverter}}" Content="Yes/No" />
        <TextBox Name="txtYesNo" />
    </StackPanel>
</Window>

C# Code:

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 WpfApplication2
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    ///
    public class YesNoConverter : IValueConverter
    {
        public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
            switch (value.ToString())
            {
                case "Yes":
                    return true;
                case "No":
                    return false;
            }
            return false;
        }
        public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
            if (value is bool)
            {
                if ((bool)value == true)
                    return "Yes";
                else
                    return "No";
            }
            return "No";
        }
    }
    public partial class MainWindow : Window
    {
     
        public MainWindow()
        {
            InitializeComponent();
        }
    }
}