I have list of items in ListBox.
All the items have buttons.
I want to show the selected items name when I click the button inside the ListBox (Not the list box items).
My Xaml:-
<ListBox SelectedIndex="{Binding SelectedIndex,Mode=TwoWay}"
SelectedItem="{Binding SelectedStudent, Mode=TwoWay}" Height="374"
ItemsSource="{Binding StudentDetails,Mode=TwoWay}"
HorizontalAlignment="Left" Margin="2,6,0,0" Name="listBox1"
VerticalAlignment="Top" Width="476" BorderBrush="#00410D0D">
<i:Interaction.Triggers>
<i:EventTrigger EventName="Tap">
<i:InvokeCommandAction Command="{Binding EventPageCommand, Mode=OneWay}"/>
</i:EventTrigger>
</i:Interaction.Triggers>
<ListBox.ItemTemplate>
<DataTemplate>
<Border BorderBrush="Gray" Padding="5" BorderThickness="1">
<StackPanel Orientation="Horizontal">
<Border BorderBrush="Wheat" BorderThickness="1">
<Image Name="ListPersonImage" Source="{Binding PersonImage}"
Height="100" Width="100" Stretch="Uniform" Margin="10,0,0,0"/>
</Border>
<TextBlock Text="{Binding FirstName}" Name="firstName" Width="200"
Foreground="White" Margin="10,10,0,0"
FontWeight="SemiBold" FontSize="22" />
<Button Height="80" Width="80" Command="{Binding addPerson}"
DataContext="{Binding DataContext, ElementName=listBox1}">
<Button.Background>
<ImageBrush
ImageSource="/NewExample;component/Images/icon_increase.png" />
</Button.Background>
</Button>
</StackPanel>
</Border>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
Here when I click the 'addPerson' Button it should show the selected items name.
Now I have write the coding for List box 'SelectedItmes'.
My ViewModel:-
private MVVMListBoxModel selectedStudent;
public MVVMListBoxModel SelectedStudent
{
get { return selectedStudent; }
set
{
if (selectedStudent == value)
return;
selectedStudent = value;
MessageBox.Show("Selected Item==>" + selectedStudent.FirstName + " Selected Index==>" + SelectedIndex);
if (SelectedIndex == 0)
{
var rootFrame = (App.Current as App).RootFrame;
rootFrame.Navigate(new Uri("/MainPage.xaml", UriKind.Relative));
}
}
}
Here I can show the selected Name when I click the list box items.
But now I want to show when I click the button.
Is it possible to show the items when I click the button?
Now I have tried like this:-
public ReactiveAsyncCommand addPerson { get; set; }
public MVVMListBoxViewModel()
{
addPerson = new ReactiveAsyncCommand();
addPerson.Subscribe(x =>
{
MessageBox.Show("Button Clicked..!!");
ListBox listbox = (ListBox)sender;
ListBoxEventsModel items = (ListBoxEventsModel)listbox.SelectedItem;
MessageBox.Show("Selected Name" + items.ToString());
});
}
But here I can not show the selected items.
Please let me any idea to solve this issue.
To make sure that your code is working
Make some tests like this:
<Button Tap="btnTestCommand_Tap" Height="80" Width="80" Command="{Binding addPerson}"
DataContext="{Binding DataContext, ElementName=listBox1}">
<Button.Background>
<ImageBrush ImageSource="/NewExample;component/Images/icon_increase.png" />
</Button.Background>
</Button>
Code behind:
private void btnTestCommand_Tap(object sender, GestureEventArgs e)
{
Button btn=sender as Button;
var command = btn.Command;
MessageBox.Show("Entering Command Check\n DataContext is of type: "+btn.DataContext.GetType().Name);
if(command !=null)
{
MessageBox.Show("Command is not null");
if(command is ReactiveAsyncCommand)
{
MessageBox.Show("Command is of ReactiveAsyncCommand type");
}
}
}
Related
I am doing an UWP app and I am using a ListView to display a list of items. I am using an ObservableCollection for that. The ListView uses multiple selection mode but when I check which items have been selected it just returns half of the selected items. Here is my code for the
XAML file
<Grid>
<StackPanel>
<TextBlock Text="{x:Bind Travel.Name}" VerticalAlignment="Top" Height="45" Width="145" FontSize="30" HorizontalAlignment="Left" Margin="20,0,0,10" />
<TextBlock Text="Select the items you want to add to the travel:" FontSize="15" HorizontalAlignment="Left" Margin="20,0,0,10"/>
<ListView x:Name="ItemsList" Margin="20, 10, 20, 20" IsItemClickEnabled="True" x:DefaultBindMode="OneWay" SelectionMode="Multiple">
<ListView.ItemTemplate>
<DataTemplate x:DataType="data:Item">
<StackPanel Orientation="Horizontal">
<TextBlock VerticalAlignment="Center" Width="100" FontSize="15" Text="{x:Bind Name}" Margin="0,0,30,0" ></TextBlock>
</StackPanel>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
<Button x:Name="AddItems" Content="Add Items" HorizontalAlignment="Left" Click="AddItems_Click" Margin="20, 10, 0, 0"/>
</StackPanel>
</Grid>
Code behind:
public ObservableCollection<Item> ItemsOfTravel { get; set; } = new ObservableCollection<Item>();
private void AddItems_Click(object sender, RoutedEventArgs e)
{
foreach(var item in ItemsList.SelectedItems)
{
ItemsOfTravel.Remove((Item)item);
}
}
I needed to get an array out of the selected items like this:
private void AddItems_Click(object sender, RoutedEventArgs e)
{
foreach(Item item in ItemsList.SelectedItems.ToArray())
{
ItemsOfTravel.Remove(item);
}
}
It seems that the selected items result was changing each time I removed an item from the Observable collection and that's is why it didn't iterate through all the items
In UWP C#, I have one ListView in upper row & another in lower row. When I drag a listitem from upper ListView & drop it on lower ListView, I am getting the source. But, I am unable to get the destination. ie) the listview item/(Folder object in my case) where I dropped.
<ListView Name="ListviewCars"
CanDragItems="True" DragItemsStarting="ListviewCars_DragItemsStarting"
SelectionMode="Single" IsItemClickEnabled="True"
DataContext="Cars" ItemsSource="{Binding CarsCollection}">
<ListView.ItemsPanel>
<ItemsPanelTemplate>
<StackPanel Background="Transparent" Height="80" Orientation="Horizontal"
HorizontalAlignment="Stretch" VerticalAlignment="Stretch" />
</ItemsPanelTemplate>
</ListView.ItemsPanel>
<ListView.ItemTemplate >
<DataTemplate>
<Grid Name="GrdCars" >
<Grid Height="80" Width="90" Padding="5">
<Grid.Background>
<ImageBrush Stretch="Uniform" ImageSource="Assets/car.png"/>
</Grid.Background>
<TextBlock Text="{Binding Name}" FontWeight="Bold" TextWrapping="Wrap" TextAlignment="Center"
HorizontalAlignment="Center" VerticalAlignment="Center" />
</Grid>
</Grid>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
<ListView Name="GrdViewImg" ScrollViewer.VerticalScrollBarVisibility="Disabled"
AllowDrop="True" DragOver="Image_DragOver"
Drop="Image_OnDrop"
DataContext="Folders" ItemsSource="{Binding FolderCollection}">
<ListView.ItemsPanel>
<ItemsPanelTemplate>
<StackPanel Background="Transparent" Height="80" Orientation="Horizontal" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" />
</ItemsPanelTemplate>
</ListView.ItemsPanel>
<ListView.ItemTemplate >
<DataTemplate>
<Grid Name="GrdForFolderMenu" RightTapped="GrdForFolderMenu_RightTapped">
<Grid Height="80" Width="90" Padding="5">
<Grid.Background>
<ImageBrush Stretch="UniformToFill" ImageSource="Assets/Folderimage.png"/>
</Grid.Background>
<TextBlock Text="{Binding Name}" FontWeight="Bold" TextWrapping="Wrap" TextAlignment="Center" HorizontalAlignment="Center" VerticalAlignment="Center" />
</Grid>
</Grid>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
I have found a simple solution myself. I get the source from DragItemsStarting event of the SoureListView. and target item (as mentioned by ashchuk) from a Grid placed inside Datatemplate of Target ListView. as shown below. Everything works fine now!
(Cars is my Source custom list item. Folders is my Target custom list item)
private void SoureListView_DragItemsStarting(object sender, DragItemsStartingEventArgs e)
{
Cars x = e.Items[0] as Cars;
string DraggedSourceCar = x.Name;
e.Data.Properties.Add("myArgs", DraggedSourceCar);
}
private void GridInsideDatatemplateOfTargetListview_Drop(object sender, DragEventArgs e)
{
var x = sender as Grid;
var y = x.DataContext as Folders;
string toMoveFolderName = y.Name;
string DraggedSourceCar = e.DataView.Properties["myArgs"].ToString();
Debug.WriteLine(DraggedSourceCar + Environment.NewLine + toMoveFolderName );
}
private void TargetListview_DragOver(object sender, DragEventArgs e)
{
e.AcceptedOperation = DataPackageOperation.Copy;
}
You have to find out by yourself = DragEventArgs.GetPosition() in the destination drop, then the underlying item with smoe helper functions
public static object GetObjectAtPoint<ItemContainer>(this ItemsControl control, Point p)
where ItemContainer : DependencyObject
{
// ItemContainer - can be ListViewItem, or TreeViewItem and so on(depends on control)
ItemContainer obj = GetContainerAtPoint<ItemContainer>(control, p);
if (obj == null)
return null;
return control.ItemContainerGenerator.ItemFromContainer(obj);
}
public static ItemContainer GetContainerAtPoint<ItemContainer>(this ItemsControl control, Point p)
where ItemContainer : DependencyObject
{
HitTestResult result = VisualTreeHelper.HitTest(control, p);
if (result != null)
{
DependencyObject obj = result.VisualHit;
while (VisualTreeHelper.GetParent(obj) != null && !(obj is ItemContainer))
{
obj = VisualTreeHelper.GetParent(obj);
}
// Will return null if not found
return obj as ItemContainer;
}
else return null;
}
Did you checked this sample?
After some research I found what DragEventArgs contains an OriginalSource property with Name matches the name of target list when Drop event invoked.
I'm not checked it with folders and subfolders, but maybe OriginalSource will contain folder where item dropped.
<TextBlock Grid.Row="1" Margin="8,4"
VerticalAlignment="Bottom"
Text="All Items"/>
<ListView x:Name="SourceListView"
Grid.Row="2" Margin="8,4"
SelectionMode="Extended"
CanDragItems="True"
DragItemsStarting="SourceListView_DragItemsStarting"/>
<TextBlock Grid.Row="1" Grid.Column="1" Margin="8,4"
VerticalAlignment="Bottom"
Text="Selection"/>
<ListView x:Name="TargetListView"
Grid.Row="2" Grid.Column="1" Margin="8,4"
AllowDrop="True" CanReorderItems="True" CanDragItems="True"
DragOver="TargetListView_DragOver"
Drop="TargetListView_Drop"
DragItemsStarting="TargetListView_DragItemsStarting"
DragItemsCompleted="TargetListView_DragItemsCompleted"/>
And here is printscreen with fired breakpoint:
EDIT:
To get an item inside of TargetList you can do a trick.
I think you use DataTemplate to display custom list items ("folders"). You can see a sample below. As you see I add Grid_DragOver trigger.
<Page.Resources>
<DataTemplate x:Key="ListViewDataTemplate">
<Grid Margin="20,5" DragOver="Grid_DragOver"
BorderBrush="White" BorderThickness="5" AllowDrop="True">
<TextBlock Margin="10" LineHeight="40" FontSize="32" FontWeight="Bold"/>
</Grid>
</DataTemplate>
</Page.Resources>
This way Grid_DragOver will be invoked when mouse pointer enter inside the Grid in DataTemplate.
And if you use binding List<YourFolderClass> as data source, you'll get folder in DataContext. For example I used this:
var SampleData = new ObservableCollection<string>
{
"My Research Paper",
"Electricity Bill",
"My To-do list",
"TV sales receipt",
"Water Bill",
"Grocery List",
"Superbowl schedule",
"World Cup E-ticket"
};
You can see all code in gist.
I have a LongListSelector with some textblocksand images inside.
How can I set the Image's visibility programmatically?
I have them set to collapsed and I want to enable them on selection_changed event of the LongListSelector.
XAML:
<phone:LongListSelector Name="LongListSel" Margin="0,-38,-22,2" ItemsSource="{Binding Items}" SelectionChanged="LongListSelector_SelectionChanged">
<phone:LongListSelector.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal" Margin="12,2,0,4" Height="110" Width="432">
<StackPanel Width="311" Margin="0,0,0,0">
<TextBlock Text="{Binding LineOne}" TextWrapping="Wrap" Margin="10,0" Style="{StaticResource PhoneTextExtraLargeStyle}" FontSize="{StaticResource PhoneFontSizeLarge}" />
<TextBlock Text="{Binding LineTwo}" TextWrapping="Wrap" Margin="10,-2,10,0" Style="{StaticResource PhoneTextSubtleStyle}" />
</StackPanel>
<StackPanel Name="playImage" Height="50" Width="50" Margin="0,0,10,0">
<Image Source="Assets/Tiles/Iconsmind-Outline-Play-Music.ico" Visibility="{Binding ImageVis}" Width="50" Height="50" HorizontalAlignment="Left" Tap="Image_Tap_1"/>
</StackPanel>
<StackPanel Name="downloadImage" Height="50" Width="50" Margin="0,0,0,0">
<Image Source="Assets/Tiles/Download.ico" Visibility="{Binding ImageVis}" Width="50" Height="50" HorizontalAlignment="Left" Tap="Image_Tap_1"/>
</StackPanel>
</StackPanel>
</DataTemplate>
</phone:LongListSelector.ItemTemplate>
</phone:LongListSelector>
</phone:PanoramaItem>
selection changed event:
private void LongListSelector_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
ItemViewModel item = new ItemViewModel();
item.ImageVis = Visibility.Visible;
//it can't be called the way you are doing it of course and it still doesn't work
}
ViewModel
private Visibility _imageVis;
public Visibility ImageVis
{
get { return _imageVis; }
set
{
_imageVis = value;
NotifyPropertyChanged("ImageVis");
}
}
Create a property of type Visibility an bind it to your image visibility.
ViewModel:
private Visibility _DownloadImage;
public Visibility DownloadImage
{
get { return _DownloadImage; }
set
{
if (_DownloadImage != value)
{
_DownloadImage = DownloadImage;
OnPropertyChanged("DownloadImage");
}
}
}
xaml
<Image Source="Assets/Tiles/Download.ico" Visibility="{Binding DownloadImage}" ... />
xaml.cs (I would prefer to bind the command also to the ViewModel, to keep the MVVM pattern)
private void LongListSelector_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
DownloadImage = Visibility.Visible;
}
Im trying to add items to the combo box from the code behind to the item template but im getting null. This is what I have so far:
XAML:
<ListBox x:Name="lsbCiertoYFalsoInsideTemplate" Margin="40,0,0,0" ItemTemplate="{StaticResource CiertoYFalsoExcerciseDataTemplate}"/>
App.xaml:
<DataTemplate x:Key="CiertoYFalsoExcerciseDataTemplate">
<Grid>
<StackPanel x:Name="stckCiertoYFalsoInsideTemplate" Margin="0" Orientation="Vertical" Width="1100">
<StackPanel x:Name="stckPreguntasCiertoYFalso" Orientation="Horizontal">
<Grid Height="50" Width="65" DataContext="{Binding CustomValueList}" VerticalAlignment="Top">
<ComboBox x:Name="cbExercises" Style="{StaticResource SA_ComboBoxStyle}" ItemsSource="{Binding CustomOption}" BorderBrush="#CC8C8C8C" VerticalAlignment="Top">
</ComboBox>
</Grid>
<TextBlock HorizontalAlignment="Center" Margin="5,3,0,0" TextWrapping="Wrap" Text="{Binding QuestionNumber}" VerticalAlignment="Top" FontWeight="Bold" Foreground="Black" Width="26" FontFamily="{Binding FontFamily, Source={StaticResource TextBlockStyleManager}}" FontSize="{Binding FontSize, Source={StaticResource TextBlockStyleManager}}"/>
<TextBlock TextWrapping="Wrap" Text="{Binding Question}" Foreground="Black" VerticalAlignment="Top" FontSize="{Binding FontSize, Source={StaticResource TextBlockStyleManager}}" Margin="10,3,0,0" Width="968" FontFamily="{Binding FontFamily, Source={StaticResource TextBlockStyleManager}}"/>
</StackPanel>
</StackPanel>
</Grid>
</DataTemplate>
The error im getting is object out of range.
Code:
private void ComboBoxExercises()
{
ComboBox comboBox = new ComboBox();
ComboboxItem item = new ComboboxItem();
item.Text = "A";
comboBox = (ComboBox)lsbCiertoYFalsoInsideTemplate.FindName("cbExercises");
comboBox.SelectedIndex = 0;
comboBox.Items.Add(item);
}
public class ComboboxItem
{
public string Text { get; set; }
public override string ToString()
{
return Text;
}
}
There's a disconnect in what you're trying to do here. You've specified an ItemTemplate - which defines how each item in the list will look.
But then you're trying to get one single ComboBox back out via the FindName function. Which leads me to believe that you're really intending to set the Template, not the ItemTemplate.
That said, I think the error you're getting is because you're setting the SelectedIndex to 0 when the ComboBox has no items in it. You're telling it to select the first one, but there's nothing to select. You should add the item first, then select it.
I know there are a lot of question like this in the web, but believe me I spent on this a lot of hours and I still not success, I really will glad for any help!
I loading various images in run time and I want to show them in list box (small images, then the user should click on one of them and show him in real size).
my code is:
public partial class MainWindow : Window
{
int imageNumber = 0;
public List<String> ImagePath = new List<String>();
public MainWindow()
{
InitializeComponent();
lb_Images.ItemsSource = ImagePath;
}
private void bu_addImage_Click(object sender, RoutedEventArgs e)
{
addImageToListBox();
}
private void addImageToListBox()
{
imageNumber++;
if (imageNumber == 4) imageNumber = 0;
string directoryPath = AppDomain.CurrentDomain.BaseDirectory;
// load input image
string ImageFilename = directoryPath + "img";
ImageFilename += imageNumber.ToString();
ImageFilename += ".jpg";
ImagePath.Add(ImageFilename);
}
}
and the xaml is:
<Window x:Class="forQuestionWPF.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow" Height="216" Width="519">
<Window.Resources>
<DataTemplate x:Key="ImageGalleryDataTemplate">
<Grid>
<Border BorderBrush="#FFFF9800" BorderThickness="1" Width="120" Height="120" Padding="5" Margin="5" CornerRadius="6">
<!--Bind Image Path in Image Control-->
<Image Source="{Binding ImagePath}" Stretch="Fill" HorizontalAlignment="Center">
<!--View Large Image on Image Control Tooltip-->
<Image.ToolTip>
<Grid>
<Image Source="{Binding ImagePath}" Stretch="Fill" HorizontalAlignment="Center" Height="200" Width="200"></Image>
</Grid>
</Image.ToolTip>
</Image>
</Border>
</Grid>
</DataTemplate>
<ItemsPanelTemplate x:Key="ImageGalleryItemsPanelTemplate">
<!--Display Images on UniformGrid Panel-->
<UniformGrid Rows="1" Columns="25" HorizontalAlignment="Center" VerticalAlignment="Stretch"/>
</ItemsPanelTemplate>
</Window.Resources>
<Grid>
<Canvas Height="177" HorizontalAlignment="Left" Name="canvas1" VerticalAlignment="Top" Width="497">
<ListBox Canvas.Left="6" Canvas.Top="5" Height="166" Name="lb_Images" Width="441"
BorderBrush="{x:Null}" DataContext="{Binding Source={StaticResource ImageGalleryDataTemplate}}"
ItemsSource="{Binding Source={StaticResource ImageGalleryItemsPanelTemplate}}">
</ListBox>
<Button Canvas.Left="453" Canvas.Top="26" Content="Add" Height="64" Name="bu_addImage" Width="38" Click="bu_addImage_Click" />
</Canvas>
</Grid>
</Window>
I know that the list box updated when I add image path to the list because if I debug I found some items under lb_Images.items, but I show nothing.
I'll glad for any help! thank you!!
Some notes
DataContext for ListBox it's not necessary, then you set ItemSource. Instead of set the ItemTemplate
In DataTemplate remove the {Binding ImagePath}, instead of write {Binding}, because in this case the elements of the DataTemplate inherit DataContext.
When you add new items to ListBox.Items, you must call ListBox.Items.Refresh() or use the ObservableCollection<T>, because:
ObservableCollection represents a dynamic data collection that provides notifications when items get added, removed, or when the whole list is refreshed.
Try this example:
XAML
<Window.Resources>
<DataTemplate x:Key="ImageGalleryDataTemplate">
<Grid>
<Border BorderBrush="#FFFF9800" BorderThickness="1" Width="120" Height="120" Padding="5" Margin="5" CornerRadius="6">
<Image Source="{Binding}" Stretch="Fill" HorizontalAlignment="Center">
<Image.ToolTip>
<Grid>
<Image Source="{Binding}" Stretch="Fill" HorizontalAlignment="Center" Height="200" Width="200" />
</Grid>
</Image.ToolTip>
</Image>
</Border>
</Grid>
</DataTemplate>
<ItemsPanelTemplate x:Key="ImageGalleryItemsPanelTemplate">
<UniformGrid Rows="1" Columns="25" HorizontalAlignment="Center" VerticalAlignment="Stretch"/>
</ItemsPanelTemplate>
</Window.Resources>
<Grid>
<Canvas Height="177" HorizontalAlignment="Left" Name="canvas1" VerticalAlignment="Top" Width="497">
<ListBox Canvas.Left="6" Canvas.Top="5" Height="166" Name="lb_Images" Width="441"
ItemTemplate="{StaticResource ImageGalleryDataTemplate}"
ItemsSource="{Binding Path=ImagePath}">
</ListBox>
<Button Canvas.Left="453" Canvas.Top="26" Content="Add" Height="64" Name="bu_addImage" Width="38" Click="bu_addImage_Click" />
</Canvas>
</Grid>
Code-behind
public partial class MainWindow : Window
{
int imageNumber = 0;
public List<String> ImagePath = new List<String>();
public MainWindow()
{
InitializeComponent();
lb_Images.ItemsSource = ImagePath;
}
private void bu_addImage_Click(object sender, RoutedEventArgs e)
{
addImageToListBox();
}
private void addImageToListBox()
{
imageNumber++;
if (imageNumber == 4) imageNumber = 0;
string directoryPath = AppDomain.CurrentDomain.BaseDirectory;
// load input image
string ImageFilename = directoryPath + "img";
ImageFilename += imageNumber.ToString();
ImageFilename += ".jpg";
ImagePath.Add(ImageFilename);
lb_Images.Items.Refresh();
}
}