c# UWP binding ComboBox SelectedItem - c#

Hello I can't seem to figure out why my combox stays empty :/
On page load the first combox gets populated with countries (from JSON), the second combobox should populate when a country is selected in the first combobox. I'm trying to fetch the SelectedItem (country) as string in a property ... SelectedItem is of type ComboBoxItem ? I think that is where it goes wrong.
The (view)model where the sorting bindable properties are:
public class LocalityModel : NotifyProp
{
#region properties
private static List<LocalityJSON> dataList;
public List<LocalityJSON> DataList
{
get
{
return dataList;
}
set {
dataList = value;
RaisePropertyChanged("Landen");
RaisePropertyChanged("Gewesten");
}
}
public List<string> Landen
{
get { if (DataList == null) return null; return (from s in DataList orderby s.Land select s.Land).Distinct().ToList<string>(); }
}
public string SelectedLand { get; set; }
public List<string> Gewesten {
get { if (DataList == null) return null; return (from s in DataList where s.Land.Equals(SelectedLand) select s.Gewest).Distinct().ToList<string>(); }
}
#endregion
#region ctor
public LocalityModel()
{
FillDataList();
}
#endregion
#region methodes
public async void FillDataList()
{
if (DataList == null)
{
DataList = await EVNT.Entries();
}
}
#endregion
}
MainPage XAML (the bindings):
<Grid Background="{ThemeResource ApplicationPageBackgroundThemeBrush}" DataContext="{Binding Source={StaticResource LocalityModel}}">
...
<TextBlock x:Name="txbCountry" Style="{StaticResource InfoLabelCountry}" />
<ComboBox x:Name="cboCountry" Style="{StaticResource CountryBox}" ItemsSource="{Binding Landen}" SelectedItem="{Binding SelectedLand, Mode=TwoWay}" />
<TextBlock x:Name="txbGewest" Style="{StaticResource InfoLabelGewest}" />
<ComboBox x:Name="cboGewest" Style="{StaticResource GewestBox}" ItemsSource="{Binding Gewesten}" />
INotifyPropertyChanged:
public class NotifyProp : INotifyPropertyChanged
{
public event PropertyChangedEventHandler PropertyChanged;
public void RaisePropertyChanged(string propertyName)
{
if (PropertyChanged != null) PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
}
The model for the JSON:
public class LocalityJSON
{
public string FB_ID { get; set; }
public string Land { get; set; }
public string Gewest { get; set; }
public string City { get; set; }
}
The JSON deserialisation (less important for the question):
public class EVNT
{
public async static Task<List<LocalityJSON>> Entries()
{
using (var client = new HttpClient())
{
client.BaseAddress = new Uri(#"http://e-vnt.com/admin/core/api/");
HttpResponseMessage response = await client.GetAsync("localityApi");
if (response.IsSuccessStatusCode)
{
String s = await response.Content.ReadAsStringAsync();
List<LocalityJSON> entries = JsonConvert.DeserializeObject<List<LocalityJSON>>(s);
return entries;
}
else
return null;
}
}
}

In your SelectedLand Property setter you need to fire PropertyChanged event the for both SelectedLand and for Gewesten.
It would probably look something like this
private string _SelectedLand;
public string SelectedLand
{
get
{
return _SelectedLand;
}
set
{
_SelectedLand = value;
RaisePropertyChanged("SelectedLand");
RaisePropertyChanged("Gewesten");
}
}
if you don't fire PropertyChanged event for Gewesten then that combobox will not know to reload is values.

Related

Populating a WPF ListBox based on a ComboBox Selection

I am trying to populate a WPF ListBox with data from a SQL Stored Procedure based on a ComboBox Selection. I've gotten the ComboBox to work like its supposed to, but I can't get the ListBox to display any data. My naming might be a little weird, but think of it as: the ComboBox gets all Recipes from SQL and the ListBox needs to display a list of Ingredients and their Amounts based on the users selection from that ComboBox. The API and Stored Procedures(...GetAll() for the ComboBox and GetByRationId() for the ListBox...) work, as I can retrieve the correct data using Swagger in the API and I can Populate the ComboBox and the RationId TextBlock in the UI, but I can't get the ListBox to show any data. I am still new to programming and I'm following tutorials etc. and I can't seem to find anything that speaks to my case specifically. I'm guessing I'm missing something. I've added the aforementioned TextBlock just to display the RationId, which is what needs to be used to get the correct data from SQL, as a test, just to make sure that the Id was getting through...and it is.
Here's the Xaml...
<StackPanel Grid.Column="1" Margin="50" Orientation="Vertical">
<ComboBox x:Name="FeedGroup" MinWidth="300" MinHeight="50"
SelectedItem="{Binding SelectedFeedGroup}">
<ComboBox.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding FeedGroupName}" />
</DataTemplate>
</ComboBox.ItemTemplate>
</ComboBox>
<TextBlock x:Name="SelectedFeedGroup_RationId" Height="81"/>
<ListBox x:Name="FeedGroupRation" MinHeight="200" Padding="20" ItemsSource="{Binding SelectedFeedGroupRation}">
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal" Margin="10" HorizontalAlignment="Center">
<TextBlock Text="{Binding CommodityName}" FontSize="20" FontWeight="Bold"
VerticalAlignment="Center" HorizontalAlignment="Center"/>
<TextBlock Text="{Binding CommodityPercentage}" FontSize="16" VerticalAlignment="Center"/>
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
</StackPanel>
Here is the ViewModel Class...
public class FeedGroupPageViewModel : Screen
{
IFeedGroupEndPoint _feedGroupEndPoint;
IFeedGroupRationEndPoint _feedGroupRationEndPoint;
IMapper _mapper;
private readonly StatusInfoViewModel _status;
private readonly IWindowManager _window;
public FeedGroupPageViewModel(IFeedGroupEndPoint feedGroupEndPoint,
IFeedGroupRationEndPoint feedGroupRationEndpoint,
IConfigHelper configHelper,
IMapper mapper,
StatusInfoViewModel status,
IWindowManager window)
{
_feedGroupEndPoint = feedGroupEndPoint;
_feedGroupRationEndPoint = feedGroupRationEndpoint;
_configHelper = configHelper;
_mapper = mapper;
_status = status;
_window = window;
}
protected override async void OnViewLoaded(object view)
{
base.OnViewLoaded(view);
try
{
await LoadFeedGroup();
}
catch (Exception ex)
{
}
}
private async Task LoadFeedGroup()
{
var FeedGroupList = await _feedGroupEndPoint.GetAll();
var feedGroup = _mapper.Map<List<FeedGroupDisplayModel>>(FeedGroupList);
FeedGroup = new BindableCollection<FeedGroupDisplayModel>(feedGroup);
}
private BindableCollection<FeedGroupDisplayModel> _feedGroup;
public BindableCollection<FeedGroupDisplayModel> FeedGroup
{
get { return _feedGroup; }
set
{
_feedGroup = value;
NotifyOfPropertyChange(() => FeedGroup);
}
}
private FeedGroupDisplayModel _selectedFeedGroup;
public FeedGroupDisplayModel SelectedFeedGroup
{
get { return _selectedFeedGroup; }
set
{
_selectedFeedGroup = value;
NotifyOfPropertyChange(() => SelectedFeedGroup);
}
}
private BindableCollection<FeedGroupRationModel> _feedGroupRation;
public BindableCollection<FeedGroupRationModel> FeedGroupRation
{
get { return _feedGroupRation; }
set
{
_feedGroupRation = value;
NotifyOfPropertyChange(() => FeedGroupRation);
}
}
private BindableCollection<FeedGroupRationModel> _selectedFeedGroupRation;
public BindableCollection<FeedGroupRationModel> SelectedFeedGroupRation
{
get { return _selectedFeedGroupRation; }
set
{
_selectedFeedGroupRation = value;
NotifyOfPropertyChange(() => SelectedFeedGroupRation);
}
}
}
And here are the Model Classes
public class FeedGroupDisplayModel : INotifyPropertyChanged
{
public int Id { get; set; }
public string UserId { get; set; }
public string FeedGroupName { get; set; }
public DateTime CreateDate { get; set; }
public DateTime LastModified { get; set; }
public int RationId { get; set; }
public event PropertyChangedEventHandler PropertyChanged;
public void CallPropertyChanged(string propertyName)
{
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
}
public class FeedGroupRationModel : INotifyPropertyChanged
{
public int Id { get; set; }
public string UserId { get; set; }
public int RationId { get; set; }
public string RationName { get; set; }
public int CommodityId { get; set; }
public string CommodityName { get; set; }
public int CommodityPercentage { get; set; }
public event PropertyChangedEventHandler PropertyChanged;
public void CallPropertyChanged(string propertyName)
{
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
}
And Here are My Endpoint Classes
public class FeedGroupEndPoint : IFeedGroupEndPoint
{
private IAPIHelper _apiHelper;
public FeedGroupEndPoint(IAPIHelper apiHelper)
{
_apiHelper = apiHelper;
}
public async Task<List<FeedGroupModel>> GetAll()
{
using (HttpResponseMessage response = await _apiHelper.ApiClient.GetAsync("/api/FeedGroup"))
{
if (response.IsSuccessStatusCode)
{
var result = await response.Content.ReadAsAsync<List<FeedGroupModel>>();
return result;
}
else
{
throw new Exception(response.ReasonPhrase);
}
}
}
}
and
public class FeedGroupRationEndPoint : IFeedGroupRationEndPoint
{
private IAPIHelper _apiHelper;
public FeedGroupRationEndPoint(IAPIHelper apiHelper)
{
_apiHelper = apiHelper;
}
public async Task<List<FeedGroupRationModel>> GetRationById()
{
using (HttpResponseMessage response = await _apiHelper.ApiClient.GetAsync("/api/FeedGroup"))
{
if (response.IsSuccessStatusCode)
{
var result = await response.Content.ReadAsAsync<List<FeedGroupRationModel>>();
return result;
}
else
{
throw new Exception(response.ReasonPhrase);
}
}
}
}
I can add more info if needed. I've been working on this for quite awhile now and I'm just out of ideas. Any help would be greatly appreciated!
Thanks in advance!!
You don't seem to set the FeedGroupRation that the ListBox binds to somewhere.
I guess you want to fetch the items and set the property when the SelectedFeedGroup property is set. You could then hook up an event handler to the PropertyChanged event or override the NotifyOfPropertyChange method. Something like this:
public override async void NotifyOfPropertyChange([CallerMemberName] string propertyName = null)
{
base.NotifyOfPropertyChange(propertyName);
if (propertyName == nameof(FeedGroup))
{
//get the items...
var results = await ...;
//set the source property
FeedGroupRation = results;
}
}
As #Michal Davis comment stated I was missing a method for loading the ration, so I added LoadFeedGroupRation()...
private async Task LoadFeedGroupRation()
{
var _feedGroupRation = await _feedGroupRationEndPoint.GetRation();
var feedGroupRation = _mapper.Map<List<FeedGroupRationDisplayModel>>
(_feedGroupPenList);
FeedGroupRationList = new BindableCollection<FeedGroupRationDisplayModel>
(feedGroupRation);
}
Also based on #EldHasp's comment I updated the SelectedFeedGroup setter...
public FeedGroupDisplayModel SelectedFeedGroup
{
get { return _selectedFeedGroup; }
set
{
_selectedFeedGroup = value;
var FeedGroupRation = LoadFeedGroup
NotifyOfPropertyChange(() => SelectedFeedGroup);
}
}
I Don't know if this was the best way but I worked for my case.

Wpf - Binding one gridcontrol selected row data and populate it in another gridcontrol

I have one gridcontrol with various fields which i havent mentioned in my code
<dxg:GridControl HorizontalAlignment="Stretch" Height="300" VerticalAlignment="Top" x:Name="grid1" AutoPopulateColumns="False" ItemsSource="{Binding Collection1}" >
<dxg:GridControl.View >
<dxg:TableView x:Name="TableView1" />
</dxg:GridControl.View>
.
.
.
.
I have another grid control on the same page with various fields
<dxg:GridControl HorizontalAlignment="Stretch" Height="250" VerticalAlignment="Top" x:Name="grid2" AutoPopulateColumns="False"
ItemsSource="{Binding ElementName="TableView1" ,path=Collection2.FocusedRow}" >
<dxg:GridControl.View >
<dxg:TableView x:Name="TableView2" />
</dxg:GridControl.View>
.
.
.
.
now collection1 Id is primary key and collection2 colID is foreign key both are having relationship with each other
Scenario here is if i select a row in grid1 all the corresponding records must be displayed in grid 2
public class myCollection: BindingList<orders>
{
public DataContext dc;
public myCollection(IList<orders> list)
: base(list)
{
}
protected override void RemoveItem(int index)
{
orders deleteItem = this.Items[index];
if (Dc.Order != null)
{
Dc.Order.DeleteOnSubmit(deleteItem);
}
base.RemoveItem(index);
}
}
My generic class for orders and generic class for master is the same
If I speak in terms of XAML properties, here you want to update ItemsSource property of 2nd Datagrid on basis of SelectedItem property of 1st Datagrid.
To achieve this, add a new property "SelectedItemDg1" in ViewModel which will hold the selection of 1st DataGrid. In Setter of this "SelectedItemDg1" property, set Collection2 as per your need.
Make sure to implement INotifyPropertyChanged interface and use ObservableCollection type for both the collections.
Following is the code sample for same :
Model Classes:
public class Country
{
public string CountryName { get; set; }
public int CountryId { get; set; }
public List<State> States { get; set; }
}
public class State
{
public string StateName { get; set; }
public int StateId { get; set; }
}
ViewModel :
public class MainWindowViewModel : INotifyPropertyChanged
{
public MainWindowViewModel()
{
CountriesCollection = new ObservableCollection<Country>();
StateCollection = new ObservableCollection<State>();
LoadData();
}
private ObservableCollection<Country> _CountriesCollection;
public ObservableCollection<Country> CountriesCollection
{
get { return _CountriesCollection; }
set
{
_CountriesCollection = value;
NotifyPropertyChanged("CountriesCollection");
}
}
private ObservableCollection<State> _StatesCollection;
public ObservableCollection<State> StateCollection
{
get { return _StatesCollection; }
set
{
_StatesCollection = value;
NotifyPropertyChanged("StateCollection");
}
}
private Country _SelectedCountry;
public Country SelectedCountry
{
get { return _SelectedCountry; }
set
{
_SelectedCountry = value;
if (_SelectedCountry != null && _SelectedCountry.States != null)
{
StateCollection = new ObservableCollection<State>(_SelectedCountry.States);
}
NotifyPropertyChanged("SelectedCountry");
}
}
private void LoadData()
{
if (CountriesCollection != null)
{
CountriesCollection.Add(new Country
{
CountryId = 1,
CountryName = "India",
States = new List<State>
{
new State { StateId = 1, StateName = "Gujarat"},
new State { StateId = 2, StateName = "Punjab"},
new State { StateId = 3, StateName = "Maharastra"}
}
});
CountriesCollection.Add(new Country
{
CountryId = 2,
CountryName = "Chine",
States = new List<State>
{
new State { StateId = 4, StateName = "Chine_State1"},
new State { StateId = 5, StateName = "Chine_State2"},
new State { StateId = 6, StateName = "Chine_State3"}
}
});
CountriesCollection.Add(new Country
{
CountryId = 3,
CountryName = "japan",
States = new List<State>
{
new State { StateId = 7, StateName = "Japan_State1"},
new State { StateId = 8, StateName = "Japan_State2"},
new State { StateId = 9, StateName = "Japan_State3"}
}
});
}
}
public event PropertyChangedEventHandler PropertyChanged;
private void NotifyPropertyChanged(String info)
{
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(info));
}
}
XALM :
<StackPanel Orientation="Horizontal" >
<DataGrid AutoGenerateColumns="True"
Height="300" Width="300"
HorizontalAlignment="Left" Margin="30"
ItemsSource="{Binding CountriesCollection}"
SelectedItem="{Binding SelectedCountry}">
</DataGrid>
<DataGrid AutoGenerateColumns="True"
Height="300" Width="300"
HorizontalAlignment="Left" Margin="30"
ItemsSource="{Binding SelectedCountry.States}">
</DataGrid>
</StackPanel>
Here I have AutoGenerateColumns property of DataGrid but you have to change it as per your requirement.
I hope this sample code will make things easy to understand for you.
The simplest and cleanest way I found to do this sort of master-details binding on collections is to wrap ObservableCollection in a class, expose its ListCollectionView and bind your ItemsSource to it, like below (it has some extra code that is used to simplify xml serialization):
public class ViewableCollection<T> : ObservableCollection<T>
{
private ListCollectionView _View;
public ViewableCollection(IEnumerable<T> items)
: base(items) { }
public ViewableCollection()
: base() { }
[XmlIgnore]
public ListCollectionView View
{
get
{
if (_View == null)
{
_View = new ListCollectionView(this);
_View.CurrentChanged += new EventHandler(InnerView_CurrentChanged);
}
return _View;
}
}
[XmlIgnore]
public T CurrentItem
{
get
{
return (T)this.View.CurrentItem;
}
set
{
this.View.MoveCurrentTo(value);
}
}
private void InnerView_CurrentChanged(object sender, EventArgs e)
{
this.OnPropertyChanged(new PropertyChangedEventArgs("CurrentItem"));
}
public void AddRange(IEnumerable<T> range)
{
if (range == null)
throw new ArgumentNullException("range");
foreach (T item in range)
{
this.Items.Add(item);
}
this.OnPropertyChanged(new PropertyChangedEventArgs("Count"));
this.OnPropertyChanged(new PropertyChangedEventArgs("Item[]"));
this.OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Add, (IList)range.ToList()));
}
public void ReplaceItems(IEnumerable<T> range)
{
if (range == null)
throw new ArgumentNullException("range");
this.Items.Clear();
foreach (T item in range)
{
this.Items.Add(item);
}
this.OnPropertyChanged(new PropertyChangedEventArgs("Count"));
this.OnPropertyChanged(new PropertyChangedEventArgs("Item[]"));
this.OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Reset));
}
public void RemoveItems(IEnumerable<T> range)
{
if (range == null)
throw new ArgumentNullException("range");
foreach (T item in range)
{
this.Items.Remove(item);
}
this.OnPropertyChanged(new PropertyChangedEventArgs("Count"));
this.OnPropertyChanged(new PropertyChangedEventArgs("Item[]"));
this.OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Remove, (IList)range.ToList()));
}
public void ClearAll()
{
IList old = this.Items.ToList();
base.Items.Clear();
this.OnPropertyChanged(new PropertyChangedEventArgs("Count"));
this.OnPropertyChanged(new PropertyChangedEventArgs("Item[]"));
this.OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Remove, old));
}
public void CallCollectionChaged()
{
this.OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Reset));
}
// necessary for xml easy serialization using [XmlArray] attribute
public static implicit operator List<T>(ViewableCollection<T> o)
{
return o == null ? default(List<T>) : o.ToList();
}
// necessary for xml easy serialization using [XmlArray] attribute
public static implicit operator ViewableCollection<T>(List<T> o)
{
return o == default(List<T>) || o == null ? new ViewableCollection<T>() : new ViewableCollection<T>(o);
}
}
Then in your ViewModel (Remember to implement INotifyPropertyChanged, I use a nuget package Fody.PropertyChanged to automatically implement it on properties):
[ImplementPropertyChanged]
public class MyViewModel
{
public ViewableCollection<MySecondViewModel> Collection1 { get; set; }
public MyViewModel()
{
this.Collection1 = new ViewableCollection<MySecondViewModel>();
}
}
[ImplementPropertyChanged]
public class MySecondViewModel
{
public string MyColumn1 { get; set; }
public string MyColumn2 { get; set; }
public ViewableCollection<MyThirdViewModel> Collection2 { get; set; }
public MySecondViewModel()
{
this.Collection1 = new ViewableCollection<MyThirdViewModel>();
}
}
[ImplementPropertyChanged]
public class MyThirdViewModel
{
public string MyColumn1 { get; set; }
public string MyColumn2 { get; set; }
}
//...
this.DataContext = new MyViewModel();
Then, keeping your grids synchronized is as simple as this:
<DataGrid ItemsSource="{Binding Collection1.View, Mode=OneWay}"
IsSynchronizedWithCurrentItem="True" />
<DataGrid ItemsSource="{Binding Collection1.CurrentItem.Collection2.View, Mode=OneWay}"
IsSynchronizedWithCurrentItem="True" />
For example binding to a Column1 property in currently selected item in currently selected Collection2 will be:
<TextBlock Text="{Binding Collection1.CurrentItem.Collection2.CurrentItem.Column1}" />
Also, you can manage selection in your code behind, for example:
Collection1.CurrentItem=null;
will clear the selection on the collection.
You can also sort (and filter and group) the ViewableCollection from code behind like this:
Collection1.View.SortDescriptions.Add(new SortDescription("Column1",ListSortDirection.Ascending));
Just remember that you should't replace the whole ViewableCollection after it's been instantiated, just add/remove items from it (for this purpose there is the method AddRange and ReplaceItems for adding/replacing items in bulk without rising CollectionChanged events unnecessarily)

Filtering a WPF Datagrid with a Textbox

I'm making this application that pulls data from a Sharepoint site using XML Node,
private XmlNode GetListItems(string listTitle)
{
var client = new Bluejeanware.MWELS.Lists();
System.Net.NetworkCredential passCredentials = new System.Net.NetworkCredential("username", "password", "domain");
client.Credentials = passCredentials;
return client.GetListItems(listTitle, string.Empty, null, null, string.Empty, null, null);
}
public void BindSPDataSource()
{
var data = GetListItems("Tasks");
var result = XElement.Parse(data.OuterXml);
XNamespace z = "#RowsetSchema";
var taskItems = from r in result.Descendants(z + "row")
select new
{
TaskName = r.Attribute("ows_LinkTitle").Value,
DueDate = r.Attribute("ows_DueDate") != null ? r.Attribute("ows_DueDate").Value : string.Empty,
AssignedTo = r.Attribute("ows_AssignedTo") != null ? r.Attribute("ows_AssignedTo").Value : string.Empty,
};
dataGridView.ItemsSource = taskItems;
}
I'd like to filter the data being pulled with a Textbox, a good example of what it should be is this Stackoverflow post
I'm having a hard time on transitioning this code into a way that it would work with the way my application is adding the data to my Datagrid, any ideas?
The following example demonstrates how to:
retrieve list data from SharePoint via SharePoint Web Services
bind to DataGrid and enable filtering
XAML:
<Window x:Class="SPO.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="Tasks" Width="800px" Height="600px" Name="TasksWindow">
<StackPanel DataContext="{Binding ElementName=TasksWindow}">
<TextBox Text="{Binding FilterString, UpdateSourceTrigger=PropertyChanged}" />
<DataGrid HorizontalAlignment="Stretch" VerticalAlignment="Stretch" ItemsSource="{Binding ListItemCollection}" />
</StackPanel>
</Window>
Code behind:
namespace SPO
{
/// <summary>
/// Interaction logic for MainWindow.xaml
/// </summary>
public partial class MainWindow : Window, INotifyPropertyChanged
{
public MainWindow()
{
InitializeComponent();
ListItemCollection = CollectionViewSource.GetDefaultView(LoadTasks());
ListItemCollection.Filter = FilterTask;
}
public bool FilterTask(object value)
{
var entry = value as TaskEntry;
if (entry != null)
{
if (!string.IsNullOrEmpty(_filterString))
{
return entry.TaskName.Contains(_filterString);
}
return true;
}
return false;
}
/// <summary>
/// Bind SP Data Source
/// </summary>
private IEnumerable<TaskEntry> LoadTasks()
{
var data = GetListItems("http://intranet.contoso.com","Tasks");
var result = XElement.Parse(data.OuterXml);
XNamespace z = "#RowsetSchema";
var taskItems = from r in result.Descendants(z + "row")
select new TaskEntry
{
TaskName = r.Attribute("ows_LinkTitle").Value,
DueDate = r.Attribute("ows_DueDate") != null ? r.Attribute("ows_DueDate").Value : string.Empty,
AssignedTo = r.Attribute("ows_AssignedTo") != null ? r.Attribute("ows_AssignedTo").Value : string.Empty,
};
return taskItems;
}
private XmlNode GetListItems(string webUri,string listTitle)
{
var client = new Lists.Lists();
client.Url = webUri + "/_vti_bin/Lists.asmx";
return client.GetListItems(listTitle, string.Empty, null, null, string.Empty, null, null);
}
public ICollectionView ListItemCollection
{
get { return _listItemCollection; }
set { _listItemCollection = value; NotifyPropertyChanged("ListItemCollection"); }
}
public event PropertyChangedEventHandler PropertyChanged;
private void NotifyPropertyChanged(string property)
{
if (PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(property));
}
}
public string FilterString
{
get { return _filterString; }
set
{
_filterString = value;
NotifyPropertyChanged("FilterString");
if (_listItemCollection != null)
{
_listItemCollection.Refresh();
}
}
}
private ICollectionView _listItemCollection;
private string _filterString;
}
public class TaskEntry
{
public string TaskName { get; set; }
public string DueDate { get; set; }
public string AssignedTo { get; set; }
}
}
Result
-First define a TaskItem class to hold the properties of each node in your OuterXml.
-Make sure your ViewModel (or your codebehind if the DataContext is set to it) implements the INorifyPropertyChanged Interface to propagate the changes in the properties to the UI).
-Then turn your taskItems into an ObservableCollection Property of the TaskItem class, and define the filter property as well which is bond to the filter TextBox.
here is the full code
public partial class MainWindow : Window, INotifyPropertyChanged
{
public MainWindow()
{
InitializeComponent();
//Populate the TaskItems collection using BindSPDataSource() method
}
private String _filter = String.Empty;
public String Filter
{
get
{
return _filter;
}
set
{
if (_filter == value)
{
return;
}
_filter = value;
OnPropertyChanged();
TaskItems = new ObservableCollection<TaskItem>(TaskItems.Where(x => x.AssignedTo.ToLower().Contains(_filter) ||
x.DueDate.ToLower().Contains(_filter) ||
x.TaskName.ToLower().Contains(_filter)
));
}
}
private ObservableCollection<TaskItem> _taskItem;
public ObservableCollection<TaskItem> TaskItems
{
get
{
return _taskItem;
}
set
{
if (_taskItem == value)
{
return;
}
_taskItem = value;
OnPropertyChanged();
}
}
public event PropertyChangedEventHandler PropertyChanged;
[NotifyPropertyChangedInvocator]
protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null)
{
PropertyChangedEventHandler handler = PropertyChanged;
if (handler != null) handler(this, new PropertyChangedEventArgs(propertyName));
}
}
public class TaskItem
{
public String TaskName { get; set; }
public String DueDate { get; set; }
public String AssignedTo { get; set; }
}
and the Xaml:
<StackPanel>
<TextBox Text="{Binding Filter,Mode=TwoWay}" HorizontalAlignment="Stretch"/>
<DataGrid ItemsSource="{Binding TaskItems}" AutoGenerateColumns="True">
</DataGrid>
</StackPanel>
and don't forget to set the DataContext :
DataContext="{Binding RelativeSource={RelativeSource Self}}"
and Finally in the constructor don't populate the DataGrid ItemSource Directly, change this in the BindSPDataSource() method :
dataGridView.ItemsSource = taskItems;
to something like this :
TaskItems=new ObservableCollection(taskItems);

C# ListBox/ListView not showing elements - Metro UI

I am using a ListBox in my Metro UI media player, but the ListBox doesn't show any text when I run it. I don't have any errors or so, but there is no text. I have also tried to use a ListView and not a ListBox, but the result was the same. What can I do ?
I am using the next code for the ListBox on the XAML part of the page
<ListBox x:Name="ItemListBox">
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel>
<TextBlock Text="{Binding PathToFile}"
FontSize="24" Margin="5,0,0,0" TextWrapping="Wrap" />
<TextBlock Text="{Binding HasVideo}"
FontSize="16" Margin="15,0,0,0"/>
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
and the next code on the page C# code :
public static ListBox ListBoxIstance = null;
public MainPage()
{
InitializeComponent();
ListBoxIstance = ItemListBox;
ItemListBox.ItemsSource = Data_Repository.MediaData.MediaList;
ItemListBox.DataContext = Data_Repository.MediaData.MediaList;
}
where MediaList is a list declared as it follows
public static List<MediaFile> MediaList = new List<MediaFile>();
and MediaFile is a class
public class MediaFile
{
public TimeSpan Duration = TimeSpan.Zero;
public bool HasAudio = false;
public bool HasVideo = false;
public String PathToFile = null;
public MediaFile(string _pathToFile)
{
PathToFile = _pathToFile;
}
}
I am using the next code to update the MediaList and the ItemListBox
foreach (var pathToFile in files)
{
MediaList.Add(new MediaFile(pathToFile.Path));
MainPage.ListBoxIstance.UpdateLayout();
}
EDIT : After some suggestions :
That's how the MediaFile class looks like :
public class MediaFile : INotifyPropertyChanged
{
private bool _hasAudio;
public bool HasAudio
{
get { return _hasAudio; }
set
{
_hasAudio = value;
OnPropertyChanged("HasAudio");
}
}
private bool _hasVideo;
public bool HasVideo
{
get { return _hasVideo; }
set
{
_hasVideo = value;
OnPropertyChanged("HasVideo");
}
}
private String _pathToFile;
public String PathToFile
{
get { return _pathToFile; }
set
{
_pathToFile = value;
OnPropertyChanged("PathToFile");
}
}
public MediaFile(string pathToFile)
{
PathToFile = pathToFile;
}
public event PropertyChangedEventHandler PropertyChanged;
protected void OnPropertyChanged(string propertyName)
{
var propertyChanged = PropertyChanged;
if (propertyChanged != null)
{
propertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
}
and I am using
public static ObservableCollection<MediaFile> MediaList = new ObservableCollection<MediaFile>();
You can't bind to public fields in your item class. Turn the class members into public properties:
public class MediaFile
{
public TimeSpan Duration { get; set; }
public bool HasAudio { get; set; }
public bool HasVideo { get; set; }
public String PathToFile { get; set; }
public MediaFile(string _pathToFile)
{
PathToFile = _pathToFile;
}
}
Then use an ObservableCollection instead of a List. That would automatically update the ItemsSource binding when items are added or removed. No need to call UpdateLayout.
public ObservableCollection<MediaFile> MediaList =
new ObservableCollection<MediaFile>();
If you also want to update the UI when any of the property values changes after a MediaFile object has been added to the list, you also have to implement the INotifyPropertyChanged interface:
public class MediaFile : INotifyPropertyChanged
{
public event PropertyChangedEventHandler PropertyChanged;
protected void OnPropertyChanged(string propertyName)
{
var propertyChanged = PropertyChanged;
if (propertyChanged != null)
{
propertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
}
private bool hasVideo
public bool HasVideo
{
get { return hasVideo; }
set
{
hasVideo = value;
OnPropertyChanged("HasVideo");
}
}
// other properties
}
You can only bind with properties and not with fields. Change fields to properties.
public bool HasVideo {get;set;}
public String PathToFile {get;set;}

How to add Item to ComboBox from UI?

Ok maybe i'm a little bit stupid but i can't find a way to Add an Item to my Combobox and get it as SelectedItem. So what do i miss?
Current Code
LoginV.XAML
<ComboBox Height="23" Margin="102,2,0,0" VerticalAlignment="Top" HorizontalAlignment="Left" Width="155"
IsEditable="True"
DisplayMemberPath="Loginname"
ItemsSource ="{Binding alleBenutzer}"
SelectedItem="{Binding selectedBenutzer}"/>
LoginVM.CS
public List<User> alleBenutzer{ get; set; }
public User selectedBenutzer
{
get { return _selectedBenutzer; }
set
{
_selectedBenutzer = value;
if (selectedBenutzer != null)
{
//do stuff
}
RaisePropertyChanged(() => Reg(() => benutzerEinrichtungen));
}
}
User.cs
public class User
{
public int Id { get; set; }
public string Loginname { get; set; }
}
Summary
How can i provide following behavior?
User runes the App added the Word "Admin" in the Combobox Control which will result in an SelectedItem != null so that i can do if(selectedBenutzer.Loginname =="Admin") DoStuff;
Use ObservableCollection instead of List for alleBenutzer:
private ObservableCollection<string> _alleBenutzer;
public ObservableCollection<string> alleBenutzer
{
get
{
return _alleBenutzer;
}
set
{
_alleBenutzer= value;
RaisePropertyChanged("alleBenutzer");
}
}
Add a button Add user.
Add AddUser() method to your ViewModel:
public void AddUser()
{
alleBenutzer.Add(new User {...});
}
Assign a RelayCommand to Click event of the button.
Assign the same RelayCommand to AddUser() method of your ViewModel
ok after some further research it turns out that i need to bind to the Text Property which contains the Value i was looking for
here an simple example
XAML
<ComboBox Height="23" HorizontalAlignment="Left" Margin="89,23,0,0" Name="comboBox1" VerticalAlignment="Top" Width="120"
IsEditable="True"
ItemsSource="{Binding mySimpleItems}"
SelectedItem="{Binding mySimpleItem}"
Text="{Binding myNewSimpleItem}"/>
Code
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
DataContext = new SimpleVM();
}
}
public class SimpleVM
{
private string _mySimpleItem;
private string _myNewSimpleItem;
private bool isNew = true;
#region properties
public ObservableCollection<string> mySimpleItems { get; set; }
public string mySimpleItem
{
get { return _mySimpleItem; }
set
{
_mySimpleItem = value;
if (_mySimpleItem != null)
{
isNew = false;
MessageBox.Show(_mySimpleItem);
}
else
isNew = true;
}
}
public string myNewSimpleItem
{
get { return _myNewSimpleItem; }
set
{
_myNewSimpleItem = value;
//if SelectedItem == null
if (isNew)
if (_myNewSimpleItem == "Super")
{
mySimpleItem = _myNewSimpleItem;
mySimpleItems.Add(_myNewSimpleItem);
}
}
}
#endregion
#region cTor
public SimpleVM()
{
var ObCol = new ObservableCollection<string>();
ObCol.Add("Max");
ObCol.Add("Dennis");
ObCol.Add("Lucas");
mySimpleItems = ObCol;
}
#endregion
}

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