Is there a way to fix the known bug of Selection Change Event, selecting does not work if the same item is tapped again.
to give further background, my scenario is that I have four items in my pivot page and when I click one of those items i will be navigated to another page. Now my dilemma is that when i select the same items again, navigation does not work or nothing happens.
Please let me know your suggested fix, thanks much in advance.
<ListBox x:Name="lbviewlist" ItemsSource="{Binding items}">
<i:Interaction.Triggers>
<i:EventTrigger EventName="selectionchanged">
<Command:EventToCommand Command ="{Binding ItemListCommand }" PassEventArgsToCommand="True" />
</i:EventTrigger>
</i:Interaction.Triggers>
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel>
<TextBlock TextWrapping="Wrap" Text="{Binding itemName}" FontSize="30" Margin="10,0,0,0" Style="{StaticResource PhoneTextTitle2Style}" Foreground="CadetBlue"/>
<TextBlock TextWrapping="Wrap" Text="{Binding itemDescription}" FontSize="20" Margin="15,5,0,10"/>
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
A good alternative approach is to include all of the content in each item inside a button, which is styled to be invisible so that you never see it, but it covers the surface of the item it encapsulates. If you're using MVVM you can bind the same command property to each of your 'buttons' and bind the DataContext of the button (your data item) to the command parameter. Then whenever you click an item you'll get the command firing every time.
You might want to change your items control to something simple so that the selection changed events dont get in the way.
Related
I am working with five text boxes and two comboboxes in xaml.
When I click on Tab key it comes from top to bottom(textboxes to comboboxes),
when I click on shift + Tab it doesn't move from combobox to textbox.
My Combobox is
<TextBlock Text="Select" Style="{StaticResource WaterMarkTextBlockStyle}" Visibility="{Binding ElementName=ComboCOM, Path=Text.IsEmpty, Converter={StaticResource BooleanToVisibilityConverter}}"/>
<ComboBox x:Name="ComboCOM" ItemsSource="{Binding COM.COM}" SelectedItem="{Binding TestResultsEntity.CountryOfOrigin,UpdateSourceTrigger=PropertyChanged,Mode=TwoWay,ValidatesOnDataErrors=True,ValidatesOnExceptions=True,NotifyOnValidationError=True}" Validation.ErrorTemplate="{StaticResource ErrorTemplateSilverlightStyle}" IsReadOnly="True" IsHitTestVisible="{Binding TestResultsIsHitTestVisible}" Margin="0" Background="Transparent" >
<i:Interaction.Triggers>
<UC:EventTriggerHandler EventName="Loaded">
<i:InvokeCommandAction Command="{Binding GetCOMComboName}" CommandParameter="{Binding ElementName=ComboCOM}"/>
</UC:EventTriggerHandler>
</i:Interaction.Triggers>
</ComboBox>
Could you please provide me the solution,thanks in advance.
Also this is an old post, I wanted to share my experience.
I came across the same problem with TextBoxes and CheckBoxes inside a Window. Tab worked for jumping to the next Control, Shift+Tab did not work.
The solution was to set TabIndex property on all controls in the Window/UserControl.
I have a simple data template for the new Windows Phone 8 LongListSelector as follows:
<DataTemplate>
<StackPanel Orientation="Horizontal" Margin="0,-6,0,-10">
<CheckBox x:Name="ToDoCheckBox" Margin="0" IsChecked="{Binding ItemIsComplete}" Checked="ToDoCheckBox_Checked"/>
<TextBlock Text="{Binding ItemName}" TextWrapping="NoWrap" Style="{StaticResource PhoneTextExtraLargeStyle}" FontSize="{StaticResource PhoneFontSizeExtraLarge}"/>
</StackPanel>
</DataTemplate>
There are suppsed to be a few more items in the template, that's why CheckBox's content property hasn't been used.
Now, I have page navigation implemented on SelectionChanged event. Problem is that, SelectionChanged even is fired even when the CheckBox is clicked. Earlier questions seem to discuss exactly opposite issue. I do not want SelectionChanged to be fired. Or, at least I don't want page to navigate on CheckBox events. I just want to have checkbox checked or unchecked event. How do I achieve that?
Selection is a bad way to trigger navigation. Without digging into that, you can avoid this by triggering the navigation when the other item in the template is tapped.
e.g.
<DataTemplate>
<StackPanel Orientation="Horizontal" Margin="0,-6,0,-10">
<CheckBox x:Name="ToDoCheckBox" Margin="0" IsChecked="{Binding ItemIsComplete}" Checked="ToDoCheckBox_Checked"/>
<TextBlock Text="{Binding ItemName}"
TextWrapping="NoWrap"
Style="{StaticResource PhoneTextExtraLargeStyle}"
FontSize="{StaticResource PhoneFontSizeExtraLarge}"
Tap="TriggerNavigationToThisItem"/>
</StackPanel>
</DataTemplate>
The above assumes you have an event called TriggerNavigationToThisItem which will trigger the navigation. You could also add a command on the Item and bind to that to trigger the navigation.
If you have a more complex template you could encapsulate them in a container (like a Grid) and then have that trigger the navigation.
You can check the original source of en every selection changed event. If it is the checkbox - simply skip execution.
Also. Don't use native "LongListSelector.Selected" property and selection event at all. It has completely no scalability (for example for multiselection). Implement it with your own Tap event handling.
Seems like this would be a common problem...
I'm using MVVM Light
I have a listbox defined in my xaml
<ListBox ItemsSource="{Binding Events}" SelectedItem="{Binding SelectedEvent, Mode=TwoWay}">
<i:Interaction.Triggers>
<i:EventTrigger EventName="Tap">
<cmd:EventToCommand Command="{Binding EventPageCommand, Mode=OneWay}"/>
</i:EventTrigger>
</i:Interaction.Triggers>
<ListBox.ItemTemplate>
<DataTemplate>
<Border Padding="0,0,0,22">
<StackPanel>
<TextBlock Text="{Binding Name}" />
<TextBlock Text="{Binding Preview}" TextWrapping="Wrap"/>
</StackPanel>
</Border>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
This works all fine and dandy, except the user is able to click below this list and the event is still fired.
I can modify it to use SelectionChanged such as:
<i:Interaction.Triggers>
<i:EventTrigger EventName="SelectionChanged">
<cmd:EventToCommand Command="{Binding EventPageCommand, Mode=OneWay}"/>
</i:EventTrigger>
</i:Interaction.Triggers>
But then if I use the back button, I cannot select the same item twice since the selection hasn't actually changed. I could probably go into my codebehind and set the selected index = -1 on page load, but this seems like quite a hack, and I use list boxes in quite a few places and I would hate to have to remember to do this hack everywhere.
Any ideas?
edit
I added background color to my listbox and my listbox items and while my listbox items only take up what space the text occupies, the listbox takes up the entire screen, extending below the last listbox item. Perhaps one way would be to shore up this extra space.
update
what seems to work best so far is to set the VerticalAlignmnet="Top" on the listbox (this shores up the extra space on the bottom, not sure why, but then scrolling ends at the bottom of the list and not the bottom of the screen). I then disabled the scrolling on the listbox itself ScrollViewer.VerticalScrollBarVisibility="Disabled" and wrapped the whole thing in a <ScrollViewer>
Currently you are looking for the Tap event on the whole of the list box, not a individual item.
This is how I typically I use interaction triggers:
<DataTemplate DataType="{x:Type ViewModel:DataItem}" x:Key="ItemTemplate">
<ContentControl>
<i:Interaction.Triggers>
<i:EventTrigger EventName="Tap">
<i:InvokeCommandAction Command="{Binding Tap}"/>
</i:EventTrigger>
<i:EventTrigger EventName="KeyUp">
<i:InvokeCommandAction
Command="{Binding RelativeSource={RelativeSource
Mode=FindAncestor,
AncestorType={x:Type ListBox}},
Path=DataContext.KeyUpCommand}"/>
</i:EventTrigger>
</i:Interaction.Triggers>
<TextBox Text="{Binding Name}"/>
</ContentControl>
</DataTemplate>
In this example the Tap event binds to a command on the DataContext (a data item) of an ItemsControl, whereas the KeyUp event binds to a command on the parent DataContext of the ListBox.
If all you want is to get an event when the user taps an item, why don't you use the trigger code you have on the Border element of the template?
You probably will have to use the Source property to bind the command to the ViewModel, but that can also be easely achieved (will just depend on how you are setting the Page DataContext right now)
I am customizing a templated multi-selection-enabled ListBox and can't easily implement the following feature - if there is only one item selected which is also current (focused), when user navigates up or down the list the selection should follow current item. I tried to subscribe to GotFocus event of the DataTemplate's StackPanel, but apparently I don't receive those events (even though MouseEnter/MouseLeave work).
I guess I could do it by modifying a somewhat similar behavior, but isn't there an easier way? This looks like a pretty basic behavior to me...
<ListBox>
<ListBox Name="lbItems" SelectionMode="Multiple">
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal"
MouseEnter="UIElement_OnMouseEnter"
MouseLeave="UIElement_OnMouseLeave"
GotFocus="UIElement_OnGotFocus">
<Rectangle Width="15" Height="15" Fill="{Binding Path=Brush}" />
<TextBlock Text="{Binding Path=Category}"/>
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
I have a probably simple problem, that I just can't seem to figure out:
I've made an ItemsControl which has its datacontext set and shows the data as pairs of Checkboxes and TextBlocks:
<ItemsControl Name="listTaskTypes" Grid.Row="1" Grid.Column="2" Grid.RowSpan="2" ItemsSource="{Binding}" Margin="10,0,0,0" VerticalAlignment="Top" Loaded="listTaskTypes_Loaded">
<ItemsControl.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<CheckBox Name="checkBoxTypeId" Tag="{Binding Path=TaskTypeID}"/>
<TextBlock FontSize="11pt" FontFamily="Helvetica" Text="{Binding Path=Text}" />
</StackPanel>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
My problem is that in the Loaded event of the ItemsControl, the checkboxes do not exist yet. How can I get an event when the ItemsControl is completely loaded or is this not possible?
listTaskTypes.ItemContainerGenerator.StatusChanged event handler can give you the notification on each item created on the ItemsControl.
Yeah Loaded is just the ItemsControl loaded event, the items might not have created at that moment. Just curious as to what you are trying to achieve here?. I guess you are trying to get the instance of CheckBox in the code behind? There may be better way using binding to achieve what you are looking for.
Try the DataContextChanged event!
When the DataContext changes, the control should be Loaded, and you can be sure it has a DataContext set as well.
Hope this helps