Windows Phone 8: LongListMultiSelector not scrollable - windows-phone-8

<StackPanel x:Name="LayoutRoot" Background="Transparent" >
<TextBlock Margin="20,20,0,0" Text="Type Text Here" HorizontalAlignment="Left"/>
<TextBox x:Name="SearchTextBox" IsReadOnly="False" HorizontalAlignment="Left" Margin="20,5,0,0" Height="70" Width="400" dp:TextBoxOnTextChangedDependency.UpdateSourceOnChange="True" Text="{Binding SearchBoxText, Mode=TwoWay}" >
<i:Interaction.Triggers>
<i:EventTrigger EventName="TextChanged">
<cmd:EventToCommand PassEventArgsToCommand="True"
Command="{Binding ElementName=SearchTextBox, Path=DataContext.SearchTextBox_TextChangedCommand}"
/>
</i:EventTrigger>
</i:Interaction.Triggers>
</TextBox>
<Grid x:Name="LayoutList" Background="{StaticResource PhoneChromeBrush}">
<toolkit:LongListMultiSelector x:Name="treksLocationItems" Background="Transparent"
ItemsSource="{Binding Path=TreksLocationItems}">
<toolkit:LongListMultiSelector.ItemTemplate>
<DataTemplate>
<Grid Margin="0,5">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<Image Width="110" Height="150" Source="{Binding PictureFilename}" VerticalAlignment="Top"/>
<StackPanel Grid.Column="1" VerticalAlignment="Top">
<TextBlock Text="{Binding Name}" Style="{StaticResource PhoneTextLargeStyle}" FontFamily="{StaticResource PhoneFontFamilySemiBold}" Margin="12,-12,12,6"/>
<TextBlock Text="{Binding ShortDescription}" Style="{StaticResource PhoneTextNormalStyle}" TextWrapping="Wrap" FontFamily="{StaticResource PhoneFontFamilySemiBold}"/>
<StackPanel Orientation="Horizontal">
<TextBlock Text="Address:" Style="{StaticResource PhoneTextSmallStyle}"/>
<TextBlock Text="{Binding Path=StreetName}" Style="{StaticResource PhoneTextSmallStyle}" FontFamily="{StaticResource PhoneFontFamilySemiBold}"/>
</StackPanel>
<StackPanel Orientation="Horizontal">
<TextBlock Text="Site:" Style="{StaticResource PhoneTextSmallStyle}"/>
<TextBlock Text="{Binding Path=Website}" Style="{StaticResource PhoneTextSmallStyle}" FontFamily="{StaticResource PhoneFontFamilySemiBold}"/>
</StackPanel>
</StackPanel>
<i:Interaction.Triggers>
<i:EventTrigger EventName="Tap">
<cmd:EventToCommand Command="{Binding Path=DataContext.TapCommand, ElementName=searchItems}" CommandParameter="{Binding Path=Id}" />
</i:EventTrigger>
</i:Interaction.Triggers>
</Grid>
</DataTemplate>
</toolkit:LongListMultiSelector.ItemTemplate>
</toolkit:LongListMultiSelector>
</Grid>
</StackPanel>
I have this code in XAML, a textbox for search and a multi line select list. The problem is that the multiLineList is not scrollable even if there are many items. If I remove the stackpanel and the textblock and textbox, the list works ok with scroll enabled. Any suggestion?

Try adding a ScrollViewer above your grid.
<ScrollViewer>
<Grid x:Name="LayoutList" ....>
...
</Grid>
</ScrollViewer>
Or you could probably replace your Grid with a ScrollViewer if you're not using it to position your elements.

Wraping LLMS in a ScrollViewer will destroy the item virtualization and throw an OutOfMemoryException if the collection is too long.
Expose the LLMS' inner LongListSelector, then use the ScrollTo() method to scroll to the item u want.
LongListMultiSelector llms = LongListMultiSelector as LongListMultiSelector;
if (llms != null && llms.ItemsSource.Count > 0)
{
llms.InnerLongListSelector.ScrollTo(llms.ItemsSource[llms.ItemsSource.Count - 1]);
}

I've encountered this weird issue and found an easy solution.
It happens for both Longlistselector and LonglistMultiselector.
When you have several controls in one page, you need to set the height of selector's row to "*" instead of "Auto" in order to make the scrolling function to work correctly.
For example :
<Grid.RowDefinitions>
<RowDefinition Height="Auto"/> //Row def for another row
<RowDefinition Height="*"/> //Row def for your selector
</Grid.RowDefinitions>
If the RowDefinition Height not set to "*" but "Auto", scrolling for Longlistselector will not response to user's action.

Related

Show default message when listbox is empty (Windows Phone 8.1)

I want to display the default message when list box is empty and for same I used following code but this code is not working :
<HubSection x:Name="PivotFromAccount" Style="{StaticResource HubSectionStyle2}" >
<DataTemplate>
<Border Style="{StaticResource brdhubsectionstyle}">
<Grid Grid.Row="1" Style="{StaticResource GridMainStyleHubSession}">
<Grid.RowDefinitions>
<RowDefinition Height="Auto"/>
<RowDefinition Height="*"/>
</Grid.RowDefinitions>
<Border Style="{StaticResource brdheaderstyle}">
<TextBlock Text="From Account" Style="{StaticResource lblheaderstyle}" />
</Border>
<ListBox x:Name="lstAccountDetailsfrom" Grid.Row="1" ItemsSource="{Binding }"
Style="{StaticResource LstBoxStyleBranches}"
Tapped="lstAccountDetailsfrom_Tapped"
ItemContainerStyle="{StaticResource lstAccountliststyle}"
ItemTemplate="{StaticResource lstAccountlistDataTemplate}" >
</ListBox>
<TextBlock Margin="4" FontStyle="Italic" FontSize="12" Text="List is empty" x:Name="txtmessage" Grid.Row="1" Foreground="Black" />
<i:Interaction.Behaviors>
<ic:DataTriggerBehavior Binding="{Binding ElementName=lstAccountDetailsfrom, Path=Items.Count,Converter={StaticResource DataTriggerBehavior},Mode=TwoWay}" Value="0" ComparisonCondition="GreaterThan">
<ic:ChangePropertyAction TargetObject="{Binding ElementName=txtmessage}" PropertyName="Visibility" Value="Collapsed"/>
</ic:DataTriggerBehavior>
</i:Interaction.Behaviors>
</Grid>
</Border>
</DataTemplate>
</HubSection>
I tried with the Ivalue converter also like below but it is also not much more helpful. It is always sending 0 count to ValueConverter
<TextBlock Margin="4" FontStyle="Italic" FontSize="12" Text="List is empty" x:Name="txtmessage" Grid.Row="1" Foreground="Black" Visibility="{Binding ElementName=lstAccountDetailsfrom,Converter={StaticResource DataTriggerBehavior},Mode=TwoWay}" />
If your data source is an ObservableCollection you can bind to its Count property with a custom IValueConverter than converts 0 to Visible and 1 to Collapsed and use it on the TextBlock. No behavior needed.

ScrollViewer scroll to specific control

I have a scrollviewer with an item template on it. the user sends a control number and I need to scroll to that item. How can I find the offset for the scrollviewer?
here is the scrollviewer that I am using
<ScrollViewer Grid.Row="0" x:Name="ScrollPanel" Padding="0">
<Grid x:Name="TestPanel" >
<ItemsControl x:Name="MainItemsControl" ItemsSource="{Binding PostList}">
<ItemsControl.ItemTemplate>
<DataTemplate>
<StackPanel x:Name="PostPanel" Margin="0,5,0,5">
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="60" />
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto" />
<ColumnDefinition Width="*" />
<ColumnDefinition Width="Auto" />
</Grid.ColumnDefinitions>
<Image x:Name="IconUrl" Source="{Binding IconUrl}" Grid.Row="0" Grid.Column="0" Margin="12,0,12,0" VerticalAlignment="Center" HorizontalAlignment="Center" Width="50"/>
<StackPanel Grid.Row="0" Grid.Column="1">
<TextBlock x:Name="PostAuthorName" Text="{Binding PostAuthorName}" TextWrapping="NoWrap" Margin="12,0,12,0" Foreground="Black" Style="{StaticResource PhoneTextNormalStyle}"/>
<TextBlock x:Name="PostTime" Text="{Binding PostTime}" TextWrapping="NoWrap" Margin="12,0,12,0" Foreground="Black" Style="{StaticResource PhoneTextSubtleStyle}"/>
</StackPanel>
<TextBlock x:Name="ReplyNumber" Text="{Binding ReplyNumber}" Grid.Row="0" Grid.Column="2" TextWrapping="NoWrap" Foreground="Black" Margin="12,0,12,0" Style="{StaticResource PhoneTextNormalStyle}" VerticalAlignment="Center"/>
</Grid>
<RichTextBox x:Name="PostContent" localcontrols:Properties.BBCode="{Binding PostContent}" />
<Rectangle Grid.Row="1" Fill="Gray" Height="1" HorizontalAlignment="Stretch" Margin="0,10,0,10"/>
</StackPanel>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
</Grid>
</ScrollViewer>
The offset can be calculated in this way. The code is adopted from this answer.
void ScrollToIndex(int index)
{
var itemContainer = MainItemsControl.ItemContainerGenerator.ContainerFromIndex(index) as UIElement;
GeneralTransform transform = itemContainer.TransformToVisual(ScrollPanel);
Point position = transform.Transform(new Point(0, 0));
ScrollPanel.ScrollToVerticalOffset(position.Y);
}
The ItemsControl does not implement logic that allows scrolling to a particular item. You can use the ListBox control instead. This control has a ScrollIntoView method that accepts the object you would like to scroll to as an argument. You can still use the RadWrapPanel by setting the ItemsPanel property of the ListBox control.
You don't have properties, but you have two methods for this: ScrollToVerticalOffset (to scroll vertically) and ScrollToHorizontalOffset (to scroll horizontally).
this.scrollViewer2.ScrollToVerticalOffset(0);

Windows Store ListView ItemStackPanel horizontal scrollbar not visible

Im having Listview which shows 185 columns and 15 rows. For showing 185 columns with 15 rows, windows store app takes some time or UI gets freezes. below is the code Im using for showing data
<ListView x:Name="outerlstView"
Height="650"
Margin="2,24,10,10" Grid.Row="1"
Grid.Column="1" BorderThickness="1" HorizontalAlignment="Stretch" VerticalAlignment="Stretch"
ItemsSource="{Binding Data,Mode=TwoWay,UpdateSourceTrigger=PropertyChanged}"
ScrollViewer.HorizontalScrollBarVisibility="Visible"
ScrollViewer.HorizontalScrollMode="Enabled" ScrollViewer.VerticalScrollBarVisibility="Auto"
SelectionMode="None" ShowsScrollingPlaceholders="True" IsZoomedInView="False"
IsSwipeEnabled="False" IsItemClickEnabled="False"
ItemContainerStyle="{StaticResource LvItemStyle}"
<ListView.ItemsPanel>
<ItemsPanelTemplate>
<StackPanel
Orientation="Vertical" VirtualizingStackPanel.VirtualizationMode="Standard"/>
</ItemsPanelTemplate>
</ListView.ItemsPanel>
<ListView.ItemTemplate>
<DataTemplate>
<ListView SelectionMode="None" IsZoomedInView="False" IsHoldingEnabled="False"
IsSwipeEnabled="False" x:Name="ListRow" ItemsSource="{Binding data, Mode=TwoWay,UpdateSourceTrigger=PropertyChanged}" HorizontalAlignment="Stretch" Width="Auto" Height="Auto"
VerticalAlignment="Center" ItemContainerStyle="{StaticResource LvItemStyle}" AllowDrop="True"
ShowsScrollingPlaceholders="True">
<interactivity:Interaction.Behaviors>
<awbehaviors:DragBehaviour/>
</interactivity:Interaction.Behaviors>
<ListView.ItemTemplate>
<DataTemplate>
<Grid Height="35" Width="120" HorizontalAlignment="Center" >
<Rectangle StrokeDashArray="1 1 0.3 1" Height="30" VerticalAlignment="Top" IsHitTestVisible="False" Opacity="0.5" Stroke="White" StrokeThickness="1" Margin="0" StrokeEndLineCap="Square" StrokeDashOffset="1.5"
Fill="{Binding ElementName=ListRow,Path=Tag,Converter={StaticResource RowNotoBackgroundConverter}}"/>
<TextBlock Text="{Binding FeedCellData,Mode=TwoWay,UpdateSourceTrigger=PropertyChanged}" HorizontalAlignment="Left"
tyle="{StaticResource GridItemTextStyle}" Width="120" AllowDrop="True" Padding="1" TextWrapping="NoWrap"
VerticalAlignment="Top" Tag="{Binding ElementName=ListRow,Path=Tag}" ToolTipService.ToolTip="{Binding FeedCellData}"
Height="{Binding Path=Tag, RelativeSource={RelativeSource Mode=Self},Converter={StaticResource RowtoHeightConverter }}" >
</TextBlock>
</Grid>
</DataTemplate>
</ListView.ItemTemplate>
<ListView.ItemsPanel>
<ItemsPanelTemplate>
<ItemsStackPanel Margin="0,0,0,0" Width="Auto" Orientation="Horizontal" Height="35" VirtualizingStackPanel.VirtualizationMode="Standard"/>
</ItemsPanelTemplate>
</ListView.ItemsPanel>
</ListView>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
the above code has listview inside it another listview. when i try to load list<list> to listview it takes too much of time. Some time app crashes when i load 100 rows with 185 columns.
I tried to replace Itemtemplate stye control to Itemstackpanel performance is good. data is loaded and shown on screen faster but i dont see Horizontal scroll
Previous Code
<ListView.ItemsPanel>
<ItemsPanelTemplate>
<StackPanel
Orientation="Vertical" VirtualizingStackPanel.VirtualizationMode="Standard"/>
</ItemsPanelTemplate>
</ListView.ItemsPanel>
<ListView.ItemTemplate>
when i modify to `<ListView.ItemsPanel>
<ItemsPanelTemplate>
<ItemsStackPanel Margin="0,0,0,0" Width="Auto" Orientation="Horizontal" Height="35" VirtualizingStackPanel.VirtualizationMode="Standard"/>
</ItemsPanelTemplate>
</ListView.ItemsPanel>`
i dont see horizontal scrollbar enabled. Can any1 suggest me how to enable Horizontal scroll bar enabled by default to Itemstackpanel in windows store apps.Looks like it is bug with this control or there work arounds to ItemsStackpanel with Horizontal Scrollbar.
If your ItensSource is a list of objects with a attribute Name and a attribute Price for example:
<ListView ItemsSource="{Binding Here_your_DataSource}" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" ScrollViewer.HorizontalScrollBarVisibility="Visible" ScrollViewer.VerticalScrollBarVisibility="Visible" >
<ListView.ItemsPanel>
<ItemsPanelTemplate>
<WrapGrid Orientation="Horizontal" MaximumRowsOrColumns="15"/>
</ItemsPanelTemplate>
</ListView.ItemsPanel>
<ListView.ItemTemplate>
<DataTemplate>
<!--Here u design your item template-->
<StackPanel Background="Blue" Width="100" Height="100">
<TextBlock Text="{Binding Name}"></TextBlock>
<TextBlock Text="{Binding Price}"></TextBlock>
</StackPanel>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>

Listpicker text-alignment to the right

I have the follwing listpicker
<toolkit:ListPicker ItemsSource="{Binding title}" Name="titlePicker" ExpansionMode="ExpansionAllowed" Grid.Row="1" Margin="0,-50,50,0" Background="White" Foreground="#FFDA3434" Canvas.ZIndex="10" HorizontalAlignment="Right" FontSize="20" Grid.RowSpan="2"/>
that contains 3 items and i would like them to align right, but for some reason i can't find the option to align the text, what am i missing?
You should do this in the ListPickerItemTemplate. Add Template to the page resources (or app resources)
<phone:PhoneApplicationPage.Resources>
<DataTemplate x:Name="ListPickerItemTemplate">
<StackPanel Orientation="Horizontal">
<TextBlock HorizontalAlignment="Right" Text="{Binding ItemName}"/>
</StackPanel>
</DataTemplate>
<DataTemplate x:Name="ListPickerFullModeItemTemplate">
<StackPanel Orientation="Horizontal">
<TextBlock HorizontalAlignment="Right" Text="{Binding ItemName}"/>
</StackPanel>
</DataTemplate>
</phone:PhoneApplicationPage.Resources>
and assign template to the picker:
<toolkit:ListPicker
ItemTemplate="{StaticResource ListPickerItemTemplate}"
FullModeItemTemplate="{StaticResource ListPickerFullModeItemTemplate}"
...

WinRT GridView Stacking

In the default application there is a gridview that displays groups of data stacked on top of each other (2 boxes high for each group).
When I implement my grid view it doesn't stack. It is just 1 horizontal list.
I've compared my GridView to the default application and it appears to be VERY SIMILAR. Is there a command I'm missing or do I have to setup my data differently?
Any help is appreciated.
My GridView:
<GridView
x:Name="itemGridView"
AutomationProperties.AutomationId="vehicleGridView"
AutomationProperties.Name="vehicles"
TabIndex="1"
Grid.Row="1"
Margin="83,0,-83,-4"
Padding="116,0,116,46"
ItemsSource="{Binding vehicles}"
ItemTemplate="{StaticResource Standard250x250ItemTemplate}"
SelectionMode="None"
IsItemClickEnabled="True"
ItemClick ="vehicleClick">
<GridView.ItemsPanel>
<ItemsPanelTemplate>
<VirtualizingStackPanel Orientation="Horizontal"/>
</ItemsPanelTemplate>
</GridView.ItemsPanel>
<GridView.GroupStyle>
<GroupStyle>
<GroupStyle.HeaderTemplate>
<DataTemplate>
<Grid Margin="1,0,0,6">
<Button
AutomationProperties.Name="VehicleMake"
Content="{Binding VehicleMake}"
Style="{StaticResource TextPrimaryButtonStyle}"/>
</Grid>
</DataTemplate>
</GroupStyle.HeaderTemplate>
<GroupStyle.Panel>
<ItemsPanelTemplate>
<VariableSizedWrapGrid Orientation="Vertical" Margin="0,0,80,0"/>
</ItemsPanelTemplate>
</GroupStyle.Panel>
</GroupStyle>
</GridView.GroupStyle>
</GridView>
Default Example:
<GridView
x:Name="itemGridView"
AutomationProperties.AutomationId="ItemGridView"
AutomationProperties.Name="Grouped Items"
Grid.RowSpan="2"
Padding="116,137,40,46"
ItemsSource="{Binding Source={StaticResource groupedItemsViewSource}}"
ItemTemplate="{StaticResource Standard250x250ItemTemplate}"
SelectionMode="None"
IsSwipeEnabled="false"
IsItemClickEnabled="True"
ItemClick="ItemView_ItemClick">
<GridView.ItemsPanel>
<ItemsPanelTemplate>
<VirtualizingStackPanel Orientation="Horizontal"/>
</ItemsPanelTemplate>
</GridView.ItemsPanel>
<GridView.GroupStyle>
<GroupStyle>
<GroupStyle.HeaderTemplate>
<DataTemplate>
<Grid Margin="1,0,0,6">
<Button
AutomationProperties.Name="Group Title"
Click="Header_Click"
Style="{StaticResource TextPrimaryButtonStyle}" >
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding Title}" Margin="3,-7,10,10" Style="{StaticResource GroupHeaderTextStyle}" />
<TextBlock Text="{StaticResource ChevronGlyph}" FontFamily="Segoe UI Symbol" Margin="0,-7,0,10" Style="{StaticResource GroupHeaderTextStyle}"/>
</StackPanel>
</Button>
</Grid>
</DataTemplate>
</GroupStyle.HeaderTemplate>
<GroupStyle.Panel>
<ItemsPanelTemplate>
<VariableSizedWrapGrid Orientation="Vertical" Margin="0,0,80,0"/>
</ItemsPanelTemplate>
</GroupStyle.Panel>
</GroupStyle>
</GridView.GroupStyle>
</GridView>
You need to use WrapGrid in your ItemsPanelTemplate. Try this.
<ItemsPanelTemplate><WrapGrid /></ItemsPanelTemplate>