How can i get value of datepicker - c#

I would get date value of my datepicker.
View :
<Grid Background="{ThemeResource ApplicationPageBackgroundThemeBrush}">
<Button Command="{Binding RecuperationDateTime}" Content="Retour" HorizontalAlignment="Left" Margin="82,567,0,0" VerticalAlignment="Top"/>
<DatePicker Name="heurePicker" Date="{Binding SerieEnCours.RecupHeure}" HorizontalAlignment="Left" Margin="82,331,0,0" VerticalAlignment="Top"/>
</Grid>
ViewModel :
`public RelayCommand RecuperationDateTime{ get; private set; }
private lenovo serieEnCours;
public lenovo SerieEnCours
{
get
{
return serieEnCours;
}
set
{
if (value != serieEnCours)
{
serieEnCours = value;
NotifyPropertyChanged();
}
}
}
public VM_lenvo(INavigationService navigationService)
{
SerieEnCours = new lenovo()
{
TarifEnCours = 0,
RecupHeure = DateTime.Now
};
_navigationService = navigationService;
RecuperationDateTime= new RelayCommand(_RecuperationDateTime);
}
private void _RecuperationDateTime()
{
DateTime heure = SerieEnCours.RecupHeure;
//Return
_navigationService.GoBack();
}`
Modele :
DateTime HeureRecuperer;
public event PropertyChangedEventHandler PropertyChanged;
public DateTime RecupHeure
{
get
{
return HeureRecuperer;
}
set
{
if (value != HeureRecuperer)
{
HeureRecuperer = value;
if (PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs("RecupHeure"));
}
}
}
}
When i generate my code, i have an "error".
I get my actually date...

If you want to let user select a date, you will have to use TwoWay data binding:
{Binding SerieEnCours.RecupHeure, Mode=TwoWay}
By default the binding only observes the changes in the view model and transmits them to the UI, but not the other way around. When you add TwoWay mode, it will also reflect UI changes in view model.

Related

Binding constant Collection to ComboBox & SelectedItem to TextBox

I'm new to MVVM in WPF and I have the following problem.
What I try to have is two ComboBoxes, each binding to the same ObservableCollection<TwoProperties> DList property as ItemsSource and with synchronized SelectedItem, so I wrote this in my XAML
<ComboBox ItemsSource="{Binding DList}" DisplayMemberPath="Property1" SelectedItem="{Binding SelectedD}" />
<ComboBox ItemsSource="{Binding DList}" DisplayMemberPath="Property2" SelectedItem="{Binding SelectedD}" />
with this viewmodel
public class ViewModel : INotifyPropertyChanged
{
private ObservableCollection<TwoProperties> _dList =
new ObservableCollection<TwoProperties> {
new TwoProperties(1,"one"),
new TwoProperties(2,"two")
};
public ObservableCollection<TwoProperties> DList
{
get { return _dList; }
set { _dList = value; OnPropertyChanged("DList"); }
}
private TwoProperties _selectedD;
public TwoProperties SelectedD
{
get { return _selectedD; }
set { _selectedD = value; OnPropertyChanged("SelectedD"); }
}
public event PropertyChangedEventHandler PropertyChanged;
protected void OnPropertyChanged(string name)
{
PropertyChangedEventHandler handler = PropertyChanged;
if (handler != null)
{
handler(this, new PropertyChangedEventArgs(name));
}
}
}
where
public class TwoProperties
{
public double Property1 { get; set; }
public string Property2 { get; set; }
public TwoProperties (double p1, string p2)
{
Property1 = p1;
Property2 = p2;
}
}
I would also like to have two TextBoxes that display the properties of the currently SelectedItem of the synchronized ComboBoxes. The properties Property1 and Property2 of SelectedD should be editable, however the ObservableCollection<TwoProperties> _dList should remain constant/readonly and not change its values.
<TextBox Text="{Binding SelectedD.Property1}" />
<TextBox Text="{Binding SelectedD.Property2}" />
But when I edit the TextBoxes and therefore SelectedD, also _dList changes its values, which is not what I want.
I hope I could explain my problem. I'm sure I'm missing something simple here.
This could be implemented easily by changing the binding mode for the TextBoxes into one way as following:
<TextBox Text="{Binding SelectedD.Property1,Mode=OneWay}" />
<TextBox Text="{Binding SelectedD.Property2,Mode=OneWay}" />
Thus when you change the textBox value, the changes would not be reflected back to the Observable collection objects.
Note that you can get rid of magical strings in your view model OnPropertyChanged by modifying the method as following:
private void OnPropertyChanged([CallerMemberName] string propertyName = "")
{
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
And then you can call it inside the setter of any property inside the view model without passing the name of the property as following:
private TwoProperties _selectedD;
public TwoProperties SelectedD
{
get { return _selectedD; }
set { _selectedD = value; OnPropertyChanged(); }
}
Edit 2:
Update my binding and view model to get the edited values inside the view model
View model updates:
private double? editPropertyOne;
public double? EditPropertyOne
{
get { return editPropertyOne; }
set
{
editPropertyOne = value;
OnPropertyChanged();
}
}
private string editPropertyTwo;
public string EditPropertyTwo
{
get { return editPropertyTwo; }
set
{
editPropertyTwo = value;
OnPropertyChanged();
}
}
private TwoProperties _selectedD;
public TwoProperties SelectedD
{
get { return _selectedD; }
set
{
_selectedD = value; OnPropertyChanged();
if (_selectedD != null)
{
EditPropertyOne = _selectedD.Property1;
EditPropertyTwo = _selectedD.Property2;
}
}
}
Xaml changes:
<TextBox Text="{Binding EditPropertyOne}" />
<TextBox Text="{Binding EditPropertyTwo}" />

How to bind with Mode=OneWay and only propagate changes back on save?

Question
How can I make it so that changes to a note are only propagated back to the list, when the Save button is clicked instead on "lost focus"?
And the Save button should only be enabled when the note has been changed.
UI
The example application looks like this:
The current behaviour is:
Clicking on a note puts its text into the TextBox; that's fine.
The changed text from the TextBox gets written back to the list when the TextBox loses the focus (default binding behaviour); but I only want that to happend when the Save button is clicked.
The Save button is always activated because the CanExecute(object parameter) isn't correctly implemented yet; it should only get activated when the TextBox text is different from the selected note's text.
My research so far
Option 1: Some Internet sources say to bind a different property to the TextBox and to programmatically check whether it is different from the SelectedItem of the ListView. I would have hoped that there was a way without introducing a third property in addition to the already existing ListOfNotes and SelectedNote.
Option 2: Some Internet sources recommend to configure Mode=OneWay so that clicking an item in the ListView updates the TextBox, but not the other way around. This sounds like the solution I would prefer, but I wasn't able to figure out from the code examples how to raise an event programmatically so that the change in the TextBox gets written back to the ListView when the Save button is clicked.
I've found other Stackoverflow questions that seem to be similar to mine, but the answers to those haven't helped me fix the problem:
WPF databinding after Save button click
Code
This example currently does two-way binding on focus lost. How do I need to change it to get the above described behaviour?
https://github.com/lernkurve/WpfBindingOneWayWithSaveButton
MainWindow.xaml
<Window x:Class="WpfBindingOneWayWithSaveButton.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:wpfBindingOneWayWithSaveButton="clr-namespace:WpfBindingOneWayWithSaveButton"
mc:Ignorable="d"
Title="MainWindow" Height="188.636" Width="299.242">
<Window.DataContext>
<wpfBindingOneWayWithSaveButton:MainWindowsViewModel />
</Window.DataContext>
<Grid>
<GroupBox Header="List of notes" HorizontalAlignment="Left" VerticalAlignment="Top" Height="112" Width="129" Margin="0,24,0,0">
<ListView ItemsSource="{Binding ListOfNotes}" SelectedItem="{Binding SelectedNote}" DisplayMemberPath="Text" HorizontalAlignment="Left" Height="79" VerticalAlignment="Top" Width="119" Margin="0,10,-2,0"/>
</GroupBox>
<GroupBox Header="Change selected note" HorizontalAlignment="Left" Margin="134,24,0,0" VerticalAlignment="Top" Height="112" Width="151">
<Grid HorizontalAlignment="Left" Height="89" Margin="0,0,-2,0" VerticalAlignment="Top" Width="141">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="40*"/>
<ColumnDefinition Width="101*"/>
</Grid.ColumnDefinitions>
<TextBox Text="{Binding SelectedNote.Text}" HorizontalAlignment="Left" Height="23" TextWrapping="Wrap" VerticalAlignment="Top" Width="121" Margin="10,7,0,0" Grid.ColumnSpan="2"/>
<Button Command="{Binding SaveCommand}" Content="Save" HorizontalAlignment="Left" VerticalAlignment="Top" Width="121" Margin="10,35,0,0" Grid.ColumnSpan="2"/>
</Grid>
</GroupBox>
</Grid>
</Window>
MainWindowsViewModel.cs
using System.Collections.ObjectModel;
using System.Windows.Input;
namespace WpfBindingOneWayWithSaveButton
{
public class MainWindowsViewModel
{
public ObservableCollection<Note> ListOfNotes { get; set; }
public Note SelectedNote { get; set; }
public ICommand SaveCommand { get; set; }
public MainWindowsViewModel()
{
ListOfNotes = new ObservableCollection<Note>
{
new Note { Text = "Note 1" },
new Note { Text = "Note 2" }
};
SaveCommand = new SaveCommand(this);
}
}
}
SaveCommand.cs
using System;
using System.Windows.Input;
namespace WpfBindingOneWayWithSaveButton
{
public class SaveCommand : ICommand
{
private MainWindowsViewModel vm;
public SaveCommand(MainWindowsViewModel vm)
{
this.vm = vm;
}
public bool CanExecute(object parameter)
{
// What should go here?
return true;
// Pseudo code
// return (is the TextBox text different from the original note text)
}
public void Execute(object parameter)
{
// What should go here?
// Pseudo code
// Let WPF know that the TextBox text has changed
// Invoke the binding so it propagates the TextBox text back to the list
}
public event EventHandler CanExecuteChanged;
}
}
Note.cs
using System.ComponentModel;
using System.Runtime.CompilerServices;
namespace WpfBindingOneWayWithSaveButton
{
public class Note : INotifyPropertyChanged
{
private string text;
public string Text
{
get { return text; }
set
{
text = value;
OnPropertyChanged();
}
}
public event PropertyChangedEventHandler PropertyChanged;
protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null)
{
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
}
}
Bind the text to the CommandParameter of the SaveButton so it gets passed to the Save method for updating.
<TextBox x:Name="NoteTextBox" Text="{Binding SelectedNote.Text, Mode=OneTime}" ../>
<Button Command="{Binding SaveCommand}"
CommandParameter="{Binding ElementName=NoteTextBox, Path=Text}",
Content="Save" />
and
public bool CanExecute(object parameter)
{
return vm.SelectedNote.Text != parameter as string;
}
public void Execute(object parameter)
{
vm.SelectedNote.Text = parameter as string;
}
Option one is the easiest to implement, you will need to clone the Note object and set it to a separate property.
in your xaml, change your list view to the following so it now binds the SelectedIndex instead of the SelectedItem.
<ListView ItemsSource="{Binding ListOfNotes}" SelectedIndex="{Binding SelectedIndex}" DisplayMemberPath="Text" ...
And change TextBox to the following so it updates the binding as you type
<TextBox Text="{Binding Path=SelectedNote.Text, UpdateSourceTrigger=PropertyChanged}" HorizontalAlignment="Left" ...
In Note.cs we add the Clone() method.
public class Note : INotifyPropertyChanged
{
public Note Clone()
{
return new Note()
{
Text = this.Text
};
}
//... The rest stays the same
}
In MainWindowsViewModel.cs we add new properties for the SelectedIndex and clone the object when we detect a index has changed. We also need to add INotifyPropertyChanged so we can update the SelectedNote from the codebehind when we do the Clone()
public class MainWindowsViewModel : INotifyPropertyChanged
{
private int _selectedIndex = -1;
private Note _selectedNote;
public int SelectedIndex
{
get { return _selectedIndex; }
set
{
if (_selectedIndex.Equals(value))
return;
_selectedIndex = value;
CloneSelectedNote();
}
}
private void CloneSelectedNote()
{
if (SelectedIndex >= 0)
{
SelectedNote = ListOfNotes[SelectedIndex].Clone();
}
else
{
SelectedNote = null;
}
}
public event PropertyChangedEventHandler PropertyChanged;
protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null)
{
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
public Note SelectedNote
{
get { return _selectedNote; }
set
{
if(Equals(_selectedNote, value))
return;
_selectedNote = value;
OnPropertyChanged();
}
}
//... The rest stays the same
}
In SaveCommand.cs we add the logic for CanExecute and add the subscriptions to CommandManager.RequerySuggested, this automatically makes it requery the CanExecute any time any binding changes. This can be a little ineffecent, if you wanted to you could expose a RaiseCanExecuteChanged() publicly but it would be MainWindowsViewModel responsibility to call it any time vm.SelectedIndex or vm.SelectedNote.Text changed.
public class SaveCommand : ICommand
{
private MainWindowsViewModel vm;
public SaveCommand(MainWindowsViewModel vm)
{
this.vm = vm;
}
public bool CanExecute(object parameter)
{
if (vm.SelectedIndex < 0 || vm.SelectedNote == null)
return false;
return vm.ListOfNotes[vm.SelectedIndex].Text != vm.SelectedNote.Text;
}
public void Execute(object parameter)
{
vm.ListOfNotes[vm.SelectedIndex] = vm.SelectedNote;
}
public event EventHandler CanExecuteChanged
{
add { CommandManager.RequerySuggested += value; }
remove { CommandManager.RequerySuggested -= value; }
}
}
UPDATE: Here is a updated version that does not use CommandManager
MainWindowsViewModel.cs
public class MainWindowsViewModel : INotifyPropertyChanged
{
private int _selectedIndex = -1;
private Note _selectedNote;
public int SelectedIndex
{
get { return _selectedIndex; }
set
{
if (_selectedIndex.Equals(value))
return;
_selectedIndex = value;
CloneSelectedNote();
RecheckSaveCommand();
}
}
private void CloneSelectedNote()
{
if (SelectedIndex >= 0)
{
SelectedNote = ListOfNotes[SelectedIndex].Clone();
}
else
{
SelectedNote = null;
}
}
public event PropertyChangedEventHandler PropertyChanged;
protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null)
{
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
public Note SelectedNote
{
get { return _selectedNote; }
set
{
if(Equals(_selectedNote, value))
return;
if (_selectedNote != null)
{
PropertyChangedEventManager.RemoveHandler(_selectedNote, SelectedNoteTextChanged, nameof(Note.Text));
}
_selectedNote = value;
if (_selectedNote != null)
{
PropertyChangedEventManager.AddHandler(_selectedNote, SelectedNoteTextChanged, nameof(Note.Text));
}
OnPropertyChanged();
}
}
private void SelectedNoteTextChanged(object sender, PropertyChangedEventArgs propertyChangedEventArgs)
{
RecheckSaveCommand();
}
private void RecheckSaveCommand()
{
var command = this.SaveCommand as WpfBindingOneWayWithSaveButton.SaveCommand; //"this." and "WpfBindingOneWayWithSaveButton." are not necessary but I wanted to be explicit.
if (command != null)
{
command.RaiseCanExecuteChanged();
}
}
//...
}
SaveCommand.cs
public class SaveCommand : ICommand
{
private MainWindowsViewModel vm;
public SaveCommand(MainWindowsViewModel vm)
{
this.vm = vm;
}
public bool CanExecute(object parameter)
{
if (vm.SelectedIndex < 0 || vm.SelectedNote == null)
return false;
return vm.ListOfNotes[vm.SelectedIndex].Text != vm.SelectedNote.Text;
}
public void Execute(object parameter)
{
vm.ListOfNotes[vm.SelectedIndex] = vm.SelectedNote;
}
public event EventHandler CanExecuteChanged;
public void RaiseCanExecuteChanged()
{
CanExecuteChanged?.Invoke(this, EventArgs.Empty);
}
}
You should not use OneWay but rather an UpdateSourceTrigger of value Explicit. BindingGroups can do this for you though, here's a simple example:
<!-- For change observation -->
<TextBlock Text="{Binding Text}"></TextBlock>
<StackPanel>
<StackPanel.BindingGroup>
<BindingGroup x:Name="EditGroup"></BindingGroup>
</StackPanel.BindingGroup>
<TextBox Text="{Binding Text}"></TextBox>
<Button>
<Button.Command>
<local:CommitGroupCommand BindingGroup="{x:Reference EditGroup}"/>
</Button.Command>
Save
</Button>
</StackPanel>
public class CommitGroupCommand : ICommand
{
public BindingGroup BindingGroup { get; set; }
public event EventHandler CanExecuteChanged;
public bool CanExecute(object parameter)
{
return true;
}
public void Execute(object parameter)
{
BindingGroup.UpdateSources();
}
}
(You could add a validation rule to your binding that requires the value to be different and use that for the CanExecute implementation.)
Using this method allows you to bind directly to the object you intend to edit, so you don't need to copy around values first.

textbox input to get / set viewmodel

I'm sure this has already been asked, but I'm still new to MVVM and WPF, and not too sure what I should be searching for.
I have a viewmodel which includes items in a Model, as well as some additional temporary data items which will all be passed to a process.start(). I have a stackpanel of textbox, and want to allow the user to type in a "ModelName", and if existing, The ViewModel will get and set "TemplateName" associated with the ModelName.
I'm a bit lost on how to implement this. Do I need to create a completely separate ViewModel, which then goes and extracts data from ModelViewModel? Do I just write some code under ModelName's set, where it can validate, query, and set TemplateName?
Model:
public partial class Model
{
public string ModelName { get; set; }
public virtual Template Template { get; set; }
and ViewModel, which takes the Model, and some temporary data:
public class LauncherViewModel:ViewModelBase
{
public LauncherViewModel()
{
_ESTContext = new ESTContext();
Models = new ObservableCollection<Model>(_ESTContext.Models);
}
private ESTContext _ESTContext;
private string _modelname;
private string _serialno;
private string _sonumber;
private string _templatename;
private string _outputname;
private Model _selectedmodel;
public ObservableCollection<Model> Models { get; set; }
public string ModelName
{
get { return _modelname; }
set
{
if (!string.Equals(_modelname, value))
{
_modelname = value;
};
}
}
public string TemplateName { get { return _templatename; }}
public string SerialNo { get { return _serialno; } }
public string SONumber { get { return _sonumber; } }
public string OutputName { get { return _outputname; } }
public Model SelectedModel
{
get { return _selectedmodel; }
set
{
if (_selectedmodel != value)
{
_selectedmodel = value;
}
}
}
}
My View:
<DockPanel>
<StackPanel Margin="0,78,0,68" Width="233" DataContext="{Binding Models}">
<ComboBox IsEditable="True" Text="{Binding ModelName}" SelectedItem="{Binding SelectedModel}"/>
<TextBox Height="23" TextWrapping="Wrap" Text="{Binding SONumber}"/>
<TextBox Height="23" TextWrapping="Wrap" Text="{Binding SerialNumber}"/>
<Button Content="Button"/>
</StackPanel>
</DockPanel>
For your gui to update you must implement INotifyPropertyChanged and a call to it on all your bound properties.
// basic base class for your models, you a
public class ModelBase : INotifyPropertyChanged
{
public event PropertyChangedEventHandler PropertyChanged;
[NotifyPropertyChangedInvocator] // remove if you are not using R#
protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null)
{
PropertyChangedEventHandler handler = PropertyChanged;
if (handler != null) handler(this, new PropertyChangedEventArgs(propertyName));
}
}
// your model
public class Model : ModelBase
{
private string modelName;
private Template template;
public string ModelName
{
get { return modelName; }
set
{
if (value == modelName) return;
modelName = value;
OnPropertyChanged();
}
}
public virtual Template Template
{
get { return template; }
set
{
if (Equals(value, template)) return;
template = value;
OnPropertyChanged();
}
}
}
View:
<DockPanel>
<StackPanel Margin="0,78,0,68" Width="233">
<ComboBox IsEditable="True" Text="{Binding ModelName, Mode='TwoWay'}" SelectedItem="{Binding SelectedModel}" ItemsSource="{Binding Models}"/>
<TextBox Height="23" TextWrapping="Wrap" Text="{Binding SONumber Mode='TwoWay'}"/>
<TextBox Height="23" TextWrapping="Wrap" Text="{Binding SerialNumber Mode='TwoWay'}"/>
<Button Content="Button"/>
</StackPanel>
Note the Mode='TwoWay' this makes the GUI change the values in your viewmodel, rather than just display them. So you need to set that on everything that's supposed to be editable as above. The default behaviour of WPF is that when a control looses focus it will update the bound property, if you set UpdateSourceTrigger='PropertyChanged' the property will be updated each time ie a letter is entered in a text box. I'll leave that part to you, but you will have to do it in your vm! At minimum the properties SONumber,SerialNumber and Models(if it's ref. changes).
VM: I assume you use galasoft here
public class LauncherViewModel : ViewModelBase
{
private ESTContext _ESTContext;
private string _templatename;
private string _modelname;
private string serialNumber;
private string _outputname;
private string modelName;
private ObservableCollection<Model> models;
private Model selectedModel;
private string soNumber;
public LauncherViewModel()
{
// dangerous ;)
_ESTContext = new ESTContext();
Models = new ObservableCollection<Model>(_ESTContext.Models);
}
public ObservableCollection<Model> Models
{
get { return models; }
set
{
if (Equals(value, models)) return;
models = value;
RaisePropertyChanged();
}
}
public string ModelName
{
get { return modelName; }
set
{
if (value == modelName) return;
modelName = value;
RaisePropertyChanged();
}
}
public string TemplateName { get { return _templatename; }}
public string SerialNumber // Note you spelled this wrong in your xaml. SONumber
{
get { return serialNumber; }
set
{
if (value == serialNumber) return;
serialNumber = value;
RaisePropertyChanged();
}
}
public string SONumber
{
get { return soNumber; }
set
{
if (value == soNumber) return;
soNumber = value;
RaisePropertyChanged();
}
}
public string OutputName { get { return _outputname; } }
public Model SelectedModel
{
get { return selectedModel; }
set
{
if (Equals(value, selectedModel)) return;
selectedModel = value;
RaisePropertyChanged();
}
}
}
A cool litle thing if you are using galasoft or sim together with R#.
public class YourViewModelBase : ViewModelBase
{
[NotifyPropertyChangedInvocator] // alt + enter = convert auto property to prop
// with backing field and change notification :)
override protected void RaisePropertyChanged([CallerMemberName] string propertyName = null)
{
base.RaisePropertyChanged(propertyName);
}
// .. :)
}
Cheers,
Stian
If I havent misunderstood your question , Bind Models to ItemsSource of ComboBox instead of Binding it to DataContext of StackPanel
Remove DataContext binding
<StackPanel Margin="0,78,0,68" Width="233" >
Bind Itemssource of ComboBox to Models and you will also have to specify DisplayMemberPath to the property of Model that you want to display in ComboBox.
<ComboBox IsEditable="True" ItemsSource="{Binding Models}" Text="{Binding ModelName}" SelectedItem="{Binding SelectedModel}"/>
And I am assuming you are setting DataContext of window to instance of LauncherViewModel class.
You need to raise the property changed event on properties you bind to i.e.:
private string _ModelName;
public string ModelName
{
get { return _ModelName; }
set
{
if (_ModelName != value)
{
_ModelName = value;
RaisePropertyChanged("ModelName");
}
}
}
In your base view model you need something like this (make sure you implement INotifyPropertyChanged):
public event PropertyChangedEventHandler PropertyChanged;
protected void RaisePropertyChanged(string propertyName)
{
if (PropertyChanged != null)
PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
In the constructor or loaded event of your view add this:
DataContext = new LauncherViewModel();

Binding data to slider doesn't work

I've got a problem with a binding in my windows phone project. I'm binding an class to a slider, but it won't update the value. If I first start the app, the binding connection is established correctly and the slider does have its correct value. But if I change the "position" or "duration" value, the slider won't update with it.
Can you please help me? I don't have any clue, what I'm doing wrong :(
Class.cs:
public class Status : INotifyPropertyChanged
{
public event PropertyChangedEventHandler PropertyChanged;
private void PropChanged(string propName)
{
if (PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(propName));
}
}
public double duration
{
get { return _duration; }
set
{
if (this._duration == value)
return;
_duration = value;
PropChanged("duration");
}
}
public double position
{
get { return _position; }
set
{
if (this._position == value)
return;
_position = value;
PropChanged("position");
}
}
}
MainPage.xaml.cs:
public partial class MainPage : PhoneApplicationPage
{
public MainPage()
{
this.ContentPanel.DataContext = _Status;
}
}
MainPage.xaml:
...
<Grid x:Name="ContentPanel" Margin="12,12,12,0" Grid.RowSpan="2">
<Slider x:Name="sl_PlayBackProgress"
Value="{Binding Path=position}"
Maximum="{Binding Path=duration}"
Height="91"
HorizontalAlignment="Left"
Margin="0,40,0,0"
VerticalAlignment="Top"
Width="408"/>
</Grid>
...
Don't know if it different from normal XAML/WPF. But in normal case I would recommend first to set up Binding.Mode to TwoWay and next just break on position.set entrance - and see the passed value

Binding drives me Crazy

Edit:
the XAML:
<TextBlock Text="{Binding Path=CurrentShows}" Grid.Row="1"/>
produces following Output:
SilverlightHelloWorld.Deserialize.schedule
the XAML:
<TextBlock Text="{Binding Path=CurrentShows.Today}" Grid.Row="1"/>
nor
<TextBlock Text="{Binding Path=CurrentShows.Today.Date}" Grid.Row="1"/>
produce any Error or ouput while being in debugmode.
Anysuggestions?
OldStatement:
I've got a quiet well complicated Example here,
the best will be, I am starting with my Code.
This is my Codebehind:
Mainpage.xaml.cs
schedule currentshows;
public schedule CurrentShows
{
protected set
{
if (currentshows != value)
{
currentshows = value;
OnPropertyChanged("CurrentShows");
}
}
get
{
return currentshows;
}
}
schedule.cs
[XmlRoot]
public class schedule : INotifyPropertyChanged
{
public event PropertyChangedEventHandler PropertyChanged;
DayCollection today;
[XmlElement("DAY")]
public DayCollection Today
{
set
{
if (today != value)
{
today = value;
OnPropertyChanged("Today");
}
}
get
{
return today;
}
}
private void OnPropertyChanged(string p)
{
if (PropertyChanged != null)
PropertyChanged(this, new PropertyChangedEventArgs(p));
}
}
DayCollection.cs
public class DayCollection : INotifyPropertyChanged
{
public event PropertyChangedEventHandler PropertyChanged;
ObservableCollection<TimeCollection> timecol;
[XmlElement("time")]
public ObservableCollection<TimeCollection> TimeCol
{
set
{
if (timecol != value)
{
timecol = value;
OnPropertyChanged("TimeCol");
}
}
get
{
return timecol;
}
}
string date;
[XmlAttribute(AttributeName = "attr")]
public string Date
{
set
{
if (date != value)
{
date = value;
OnPropertyChanged("Date");
}
}
get
{
return date;
}
}
private void OnPropertyChanged(string p)
{
if (PropertyChanged != null)
PropertyChanged(this, new PropertyChangedEventArgs(p));
}
}
I am trying to get the String-Property "Date" in my Xaml to Show-Up.
But I am just don't get any Solution.
I totally would appreciate any help here, Thanks in Advance !
I've copied your code into a project and it works if you use this line instead to set up the TextBlock's binding
<TextBlock Text="{Binding Today.Date}" Grid.Row="1"/>
but I cannot tell from your code how you are setting up the outer data binding. Here's what I included in the MainPage constructor
currentshows = new schedule();
currentshows.Today = new DayCollection();
currentshows.Today.Date = "hallo";
LayoutRoot.DataContext = currentshows;
where LayoutRoot is the parent of the TextBlock, i.e.
<Grid x:Name="LayoutRoot">
<TextBlock Text="{Binding Today.Date}"/>
</Grid>

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