Hiding an element when "ImageBrush" image fails to load - xaml

I'm using an OpacityMask with an ImageBrush, and would like to hide the element in cases where the image fails to load. I tried using an EventTrigger, but this is
<Rectangle x:Name="imageRoot"
HorizontalAlignment="Stretch" VerticalAlignment="Stretch"
Fill="{StaticResource PhoneForegroundBrush}"
>
<Rectangle.OpacityMask>
<ImageBrush ImageSource="{Binding ImagePath}" Stretch="Uniform">
<i:Interaction.Triggers>
<i:EventTrigger EventName="ImageFailed">
<ei:ChangePropertyAction PropertyName="Visibility"
TargetName="imageRoot">
<ei:ChangePropertyAction.Value>
<Visibility>Collapsed</Visibility>
</ei:ChangePropertyAction.Value>
</ei:ChangePropertyAction>
</i:EventTrigger>
</i:Interaction.Triggers>
</ImageBrush>
</Rectangle.OpacityMask>
</Rectangle>
This seems to just fail silently: there are no compile-time errors, nor runtime nor binding errors but the element does not collapse.

For some reason, "TargetName=imageRoot" is failing to bind the action to the element. Using TargetObject="{Binding ElementName=imageRoot}" does work, however.

Related

ToggleButton EventTriggerBehavior- binding image to background of togglebutton

i have the following code in my xaml :
<ToggleButton x:Name="play" Command="{Binding OnPlayButton}" CommandParameter="{Binding ElementName=media , Mode=TwoWay}" HorizontalAlignment="Left" Margin="573,638,0,0" VerticalAlignment="Top" Height="50" Width="50">
<Image Name="MyImage" Source="Images/Control/Play.png"/>
<interactivity:Interaction.Behaviors>
<core:EventTriggerBehavior EventName="Checked">
<core:ChangePropertyAction PropertyName="MyImage" Value="{Binding Source=Images/Control/Pause.png}" />
</core:EventTriggerBehavior>
<core:EventTriggerBehavior EventName="Unchecked">
<core:ChangePropertyAction PropertyName="MyImage" Value="{Binding Source=Images/Control/Play.png}" />
</core:EventTriggerBehavior>
</interactivity:Interaction.Behaviors>
</ToggleButton>
What i'm trying to achieve is change the background of the togglebutton to pause.png when its clicked and change it to play.png when clicked again. I'm getting exception in the xaml , is this the correct way ?
You are almost there with Behaviors. But PropertyName is Not Image It is Source. And TargetObject is MyImage
Your code should be something like below.
<ToggleButton HorizontalAlignment="Center" VerticalAlignment="Center" IsChecked="True">
<Interactivity:Interaction.Behaviors>
<Core:EventTriggerBehavior EventName="Checked">
<Core:ChangePropertyAction TargetObject="{Binding ElementName=MyImage}" PropertyName="Source" Value="Images/Control/Pause.png" />
</Core:EventTriggerBehavior>
<Core:EventTriggerBehavior EventName="Unchecked">
<Core:ChangePropertyAction TargetObject="{Binding ElementName=MyImage}" PropertyName="Source" Value="Images/Control/Play.png"/>
</Core:EventTriggerBehavior>
</Interactivity:Interaction.Behaviors>
<Image x:Name="MyImage" Source="Images/Control/Play.png" Width="100" Height="100"/>
</ToggleButton>
Good Luck.
You can't use PropertyName="MyImage" as "MyImage" is the name of a control, not a property of ToggleButton!
The easiest way to do what you want is to add the two images one after the other and change visibility according to the control state:
<ToggleButton x:Name="play">
<Image Source="Images/Control/Play.png" Visibility="{Binding IsChecked, ElementName=play, Converter={StaticResource BooleanToVisibilityConverter}" />
<Image Source="Images/Control/Stop.png" Visibility="{Binding IsChecked, ElementName=play, Converter={StaticResource InverterBooleanToVisibilityConverter}" />
</ToggleButton>
On the example above I'm using two converter instances for something that converts a bool value to a Visibility value. You can write your own or just use a 3rd party one like the BooleanToVisibilityConverter from Cimbalino Toolkit.

How to make a Stack Panel Visible based on the Tapped Event of a ListView in Windows Phone 8.1?

In my application, I am having a ListView. ListView lists a set of images.
So when the application is running, and when that page is loaded, a list of images are shown.
<ListView ItemsSource="{Binding imageLists}" Background="Red" Tapped="ListView_Tapped">
<ListView.ItemTemplate>
<DataTemplate>
<Grid Background="Green">
<Image Source="{Binding imagePath}" CacheMode="BitmapCache" Stretch="UniformToFill"/>
<StackPanel Name="imageTitle" Visibility="Collapsed" Background="Blue"
HorizontalAlignment="Center" VerticalAlignment="Center">
<TextBlock Foreground="White" Text="Dumy Image Title" FontSize="10"/>
</StackPanel>
</Grid>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
As you can see from the code, I have one image & stackpanel inside the listview. And the stackpanel's visibility has been set to collapsed for convenience.
The StackPanel imageTitle resides inside the ListView. Stackpanel contains a TextBlock housing the images name. For now it's dumy text.
On Tapping any image in the list, I am trying to make the stackPanel visible.
The Code Behind:
private void ListView_Tapped(object sender, TappedRoutedEventArgs e)
{
imageTitle.Visibility = Windows.UI.Xaml.Visibility.Visible;
}
Since the stackpanel is inside the listview & I am trying to make it visible on the tap event of the listview, I am not able to acheive the needed result. I know my code is wrong.
If I specify the stackpanel outside the listview, I can make it visible using the code I gave inside the ListView_Tapped function. But even in that case, I need to show the stackpanel (name of the image I clicked) inside the listview item (image I clicked).
Any help??
Can this be achieved using only XAML?
Here's a pure xaml way.
Rather than changing the Visibility of the imageTitle (not a great UX), let's change its Opacity to make its appearing more interesting.
First we need to create a storyboard inside this data template. This storyboard will fade in the imageTitle in 400ms.
And then we drag a ControlStoryboard behavior from Expression Blend's Asset panel onto the top level Grid. Basically we want the storyboard to fire off when this Grid is tapped.
Please see below code for reference.
<DataTemplate x:Key="GroupTemplate">
<Grid Background="Green">
<Grid.Resources>
<Storyboard x:Name="ShowImageTitleStoryboard">
<DoubleAnimation Duration="0:0:0.4" To="1" Storyboard.TargetProperty="(UIElement.Opacity)" Storyboard.TargetName="imageTitle"/>
</Storyboard>
</Grid.Resources>
<Interactivity:Interaction.Behaviors>
<Core:EventTriggerBehavior EventName="Tapped">
<Media:ControlStoryboardAction Storyboard="{StaticResource ShowImageTitleStoryboard}"/>
</Core:EventTriggerBehavior>
</Interactivity:Interaction.Behaviors>
<Image Source="{Binding Image}" CacheMode="BitmapCache" Stretch="UniformToFill"/>
<StackPanel x:Name="imageTitle" Background="Blue"
HorizontalAlignment="Center" VerticalAlignment="Center" Opacity="0">
<TextBlock Foreground="White" Text="Dumy Image Title" FontSize="10"/>
</StackPanel>
</Grid>
</DataTemplate>
Apart from JustinXL's answer it can also be done by using ChangePropertyAction. Also pure XAML:
<DataTemplate>
<Grid Background="Green">
<Image Source="{Binding imagePath}" CacheMode="BitmapCache" Stretch="UniformToFill">
<i:Interaction.Behaviors>
<ic:EventTriggerBehavior EventName="Tapped">
<ic:ChangePropertyAction TargetObject="{Binding ElementName=imageTitle}" PropertyName="Visibility" Value="Visible"/>
</ic:EventTriggerBehavior>
</i:Interaction.Behaviors>
</Image>
<StackPanel Name="imageTitle" Visibility="Collapsed" Background="Blue"
HorizontalAlignment="Center" VerticalAlignment="Center">
<TextBlock Foreground="White" Text="Dumy Image Title" FontSize="10"/>
</StackPanel>
</Grid>
</DataTemplate>
It's just another way to change a property - JustinXL's answer will provide nice animation with opacity, which will look much better.
I dunno why you specifically want to handle the scenario using XAML. For the Microsoft's recommended MVVM model you should bind a property to your element field and then you can write a converter for the same to return back "Visible" or "Collapse".

Windows Phone 8 Nokia Maps: How to change the design of a Microsoft.Phone.Maps.Toolkit Pushpin?

Default, they look like this: http://wp.qmatteoq.com/wp-content/uploads/2013/01/map.png. I would like to have them look like on Nokia Maps, like this: http://www.themobileindian.com/images/nnews/2012/11/9225/Nokia-Maps.jpg, so they take less space. And everytime I tap on them, they will toggle between icon and description.
Lets say I have two templates for pushpin in resources:
<ControlTemplate x:Key="1" TargetType="maptk:Pushpin">
<Grid x:Name="ContentGrid" Background="Transparent" Margin="-4,0,0,0">
<StackPanel >
<Grid Background="Black">
<StackPanel Margin="5,5,0,0">
<i:Interaction.Triggers>
<i:EventTrigger EventName="Tap">
<cmd:EventToCommand PassEventArgsToCommand="False"
CommandParameter="{Binding}"
Command="{Binding ElementName=NearbyMap, Path=DataContext.Pushpin_OnTapCommand}"/>
</i:EventTrigger>
</i:Interaction.Triggers>
<TextBlock Text="{Binding Location}" Foreground="White" />
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding LocationName}" Foreground="White" />
<TextBlock Text="-" Foreground="White" Padding="3,0"/>
<TextBlock Text="{Binding LocationName}" Foreground="White" />
</StackPanel>
<TextBlock Text="{Binding LocationName}" Foreground="White" />
<TextBlock Text="{Binding LocationName}" Foreground="White" />
</StackPanel>
</Grid>
<Polygon Fill="Black" Points="0,0 29,0 0,29" Width="29" Height="29" HorizontalAlignment="Left" />
<Grid Height="26" Width="26" Margin="-13,-13,0,0" RenderTransformOrigin="0.5,0.5" HorizontalAlignment="Left">
<Grid.RenderTransform>
<CompositeTransform Rotation="-45"/>
</Grid.RenderTransform>
<Rectangle Fill="Black" HorizontalAlignment="Center" Margin="0" Stroke="White" VerticalAlignment="Center" Height="26" Width="26" />
<Ellipse HorizontalAlignment="Center" Height="16" Margin="0" VerticalAlignment="Center" Fill="Green" Width="16" />
</Grid>
</StackPanel>
</Grid>
</ControlTemplate>
<ControlTemplate TargetType="maptk:Pushpin" x:Key="2">
<Grid Height="26" Width="26" Margin="-13,-13,0,0" RenderTransformOrigin="0.5,0.5" >
<Grid.RenderTransform>
<CompositeTransform Rotation="-45"/>
</Grid.RenderTransform>
<Rectangle Fill="Black" HorizontalAlignment="Center" Margin="0" Stroke="White" VerticalAlignment="Center" Height="26" Width="26"/>
<Ellipse HorizontalAlignment="Center" Height="16" Margin="0" VerticalAlignment="Center" Fill="Red" Width="16"/>
</Grid>
</ControlTemplate>
and the pushpin control:
<maptk:Pushpin x:Name="PushPins" GeoCoordinate="{Binding Location}" Visibility="Visible" Content="{Binding LocationName}" Template="{StaticResource 2}"/>
How can I switch between them with some triggers or something?
#Rares found another solution, that works great in my case...
So the general issue here is just, how to switch/change the design when tapping the pushpin.
Well it seems that when you add the pushpins to the map they get their design from the toolkit, but you still are able to change that by setting the Style propery in code!
So if you hook up each pushpin to a pushpin tap event you can just do the following in your code behind of the XAML page:
private void Pushpin_Tap(object sender, System.Windows.Input.GestureEventArgs e)
{
((Pushpin)sender).Style = Application.Current.Resources["PushpinStyle"] as Style;
}
Provided you created a PushpinStyle inside a resourcedictionary that has a Pushpin as TargetType.
To be able to reset the design when pushing on another pushpin, I just keep a reference to the pushpin pressed and reset it's style before changing the style of the newly pressed one!
Works great for me...
You can use a general trick to modify the look of TK components. This can be used for nearly all TK components.
All TK components have styles (defined in XAML), these are not settable via code. But you can override the style in your applicatoin (keep in mind, you override the style in general, so if you modify e.g. pushpin styles, all pushpins inside your app will look like that)
A bit more in detail:
a) Get the TK source from https://phone.codeplex.com/sourcecontrol/latest
b) Have a look into Themes/Generic.xaml
c) Next to the last element, you see the style definition for the pushpin.
Starts with:
<!-- Default Style used for Pushpin -->
<Style TargetType="maptk:Pushpin">
...
d) Copy this style (or you can write it from scratch of course) and modify the style to whatever you like
e) Add this modified code snippet to your Application.Resources (e..g. the Application.Resources section in your App.xaml)
Keep in mind, you also need to reference the right TK namespace.
For pushpin, you need to include:
xmlns:maptk="clr-namespace:Microsoft.Phone.Maps.Toolkit"
Now your app uses the locally overriden style for your pushpin.
Btw: Since TK is Ms-PL licensed, keep in mind that there are probably license restrictions if you take the original source code from MSFT.
I personally found it easier to not use the toolkit for pushpins. Instead I wrote a user control "PushPinUC" that I designed how I wanted it. The UserControl subscribes to the Tap event - so I can expand/retract when it's pressed.
You can add user controls to your Map control using the following code.
private void BindPushpins(IEnumerable<PushpinIVM> pushpins)
{
foreach (var pushpin in pushpins)
{
var pushPinUC = new PushpinUC { Pushpin = pushpin };
var mapOverlay = new MapOverlay { GeoCoordinate = pushpin.Location, Content = pushPinUC };
var mapLayer = new MapLayer { mapOverlay };
Map.Layers.Add(mapLayer);
}
}
I found a solution: add only one control template to the pushpins. The stackpanel is the pushpin with the textbox and the grid before the stackpanel is the pushpin without the textbox. The stackpanel is with visibility collapsed. As you can see there are 2 triggers for the tap event, where i just set the visibility of the pushpin with the textbox to visible or collapsed. You can use any image for the pushpins.
<ctrls:BaseUserControl.Resources>
<ControlTemplate x:Key="PushPinTemplate" TargetType="maptk:Pushpin">
<Grid x:Name="ContentGrid" Background="Transparent" Margin="-4,0,0,0">
<Grid Height="40" Width="30" Margin="-13,-13,0,0" RenderTransformOrigin="0.5,0.5" >
<Image Source="/Assets/Images/push1.png" Width="40" Height="40">
<i:Interaction.Triggers>
<i:EventTrigger EventName="Tap">
<cmd:EventToCommand PassEventArgsToCommand="True"
Command="{Binding ElementName=NearbyMap, Path=DataContext.Rectangle_OnTapCommand}"/>
</i:EventTrigger>
</i:Interaction.Triggers>
</Image>
</Grid>
<StackPanel x:Name="DetailsPanel" Visibility="{Binding Path=Visibility}">
<Grid x:Name="TestGrid" Background="Black">
<StackPanel Margin="5,5,0,0">
<!--TextBlock tap-->
<i:Interaction.Triggers>
<i:EventTrigger EventName="Tap">
<cmd:EventToCommand PassEventArgsToCommand="True"
Command="{Binding ElementName=NearbyMap, Path=DataContext.Pushpin_OnTapCommand}"/>
</i:EventTrigger>
</i:Interaction.Triggers>
<TextBlock Text="{Binding LocationName}" Foreground="White" FontSize="25"/>
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding StreetName}" Foreground="White" />
<TextBlock Text="{Binding StreetNumber}" Foreground="White" />
</StackPanel>
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding DistanceToDisplay}" Foreground="White" />
</StackPanel>
</StackPanel>
</Grid>
<Polygon Fill="Black" Points="0,0 29,0 0,29" Width="29" Height="29" HorizontalAlignment="Left" Visibility="Visible"/>
<Grid Height="40" Width="30" Margin="-13,-13,0,0" RenderTransformOrigin="0.5,0.5" HorizontalAlignment="Left">
<Image Source="/Assets/Images/push2.png" Width="40" Height="40">
<i:Interaction.Triggers>
<i:EventTrigger EventName="Tap">
<cmd:EventToCommand PassEventArgsToCommand="True"
Command="{Binding ElementName=NearbyMap, Path=DataContext.Rectangle_OnTapCommand}"/>
</i:EventTrigger>
</i:Interaction.Triggers>
</Image>
</Grid>
</StackPanel>
</Grid>
</ControlTemplate>
</ctrls:BaseUserControl.Resources>
<Grid x:Name="ContentPanel" Grid.Row="1" Margin="12,0,12,0">
<maps:Map x:Name="NearbyMap"
Center="{Binding MapCenter, Mode=TwoWay}"
ZoomLevel="15"
dp:MapPushPinDependency.ItemsSource="{Binding Path=Locations, Mode=OneWay}"
>
<i:Interaction.Triggers>
<i:EventTrigger EventName="Tap">
<cmd:EventToCommand PassEventArgsToCommand="True"
Command="{Binding ElementName=NearbyMap, Path=DataContext.Map_OnTapCommand}"/>
</i:EventTrigger>
</i:Interaction.Triggers>
<maptk:MapExtensions.Children>
<maptk:MapItemsControl Name="StoresMapItemsControl">
<maptk:MapItemsControl.ItemTemplate>
<DataTemplate>
<maptk:Pushpin x:Name="PushPins" GeoCoordinate="{Binding Location}" Visibility="Visible" Content="{Binding LocationName}" Template="{StaticResource PushPinTemplate}"/>
</DataTemplate>
</maptk:MapItemsControl.ItemTemplate>
</maptk:MapItemsControl>
<maptk:UserLocationMarker x:Name="UserLocationMarker" Visibility="Visible" GeoCoordinate="{Binding MyLocation}"/>
</maptk:MapExtensions.Children>
</maps:Map>
</Grid>
#Depechie
private void RectangleTapAction(GestureEventArgs e)
{
var pushpinControl = TryFindParent<Pushpin>(e.OriginalSource as UIElement);
var pushpin = (pushpinControl as FrameworkElement).DataContext as PushPinModel;
Locations.Where(t => t.Id != pushpin.Id).ToList().ForEach(t => t.Visibility = Visibility.Collapsed);
pushpin.Visibility = pushpin.Visibility == Visibility.Visible ? Visibility.Collapsed : Visibility.Visible;
e.Handled = true;
}
Locations is an ObservableCollection and there is a Linq where I hide the textbox for other pushpins. PushPinModel has an attribute representing the visibility.

How to implement smooth transitions between containers in WinRT?

I have a Silverlight 4 game that I'm attempting to port to WinRT. It makes heavy use of Blend's FluidMoveBehavior to animate item transitions between containers (items float from one container to another). It appears that this functionality is missing from WinRT, and I have been unable to find a substitute.
In Silverlight, this XAML does it all:
<ItemsPanelTemplate x:Key="TransitioningPanelTemplate">
<StackPanel Orientation="Horizontal" Margin="0" Background="Transparent">
<i:Interaction.Behaviors>
<il:FluidMoveBehavior AppliesTo="Children" Duration="0:0:0.400" Tag="DataContext">
<il:FluidMoveBehavior.EaseY>
<BackEase EasingMode="EaseInOut" Amplitude="0.35" />
</il:FluidMoveBehavior.EaseY>
<il:FluidMoveBehavior.EaseX>
<BackEase EasingMode="EaseInOut" Amplitude="0.35" />
</il:FluidMoveBehavior.EaseX>
</il:FluidMoveBehavior>
</i:Interaction.Behaviors>
</StackPanel>
</ItemsPanelTemplate>
I looked into Transitions as suggested in this post, but this appears to only work within a single container.
Is there some use of Transitions that will allow this behavior? If not, is anyone aware of possible alternatives?
Try this
<ItemsPanelTemplate x:Key="TransitioningPanelTemplate">
<StackPanel Orientation="Horizontal" Margin="0" Background="Transparent">
<StackPanel.ChildrenTransitions>
<TransitionCollection>
<Your Transitions />
</TransitionCollection>
</StackPanel.ChildrenTransitions>
<i:Interaction.Behaviors>
<il:FluidMoveBehavior AppliesTo="Children" Duration="0:0:0.400" Tag="DataContext">
<il:FluidMoveBehavior.EaseY>
<BackEase EasingMode="EaseInOut" Amplitude="0.35" />
</il:FluidMoveBehavior.EaseY>
<il:FluidMoveBehavior.EaseX>
<BackEase EasingMode="EaseInOut" Amplitude="0.35" />
</il:FluidMoveBehavior.EaseX>
</il:FluidMoveBehavior>
</i:Interaction.Behaviors>
</StackPanel>

Custom pushpins and templating images

This is probably something simple but I am tearing my hair out at the moment.
I want to display pushpins on a map from a model. So I have created a template for the pushpins
<ControlTemplate x:Key="PushpinTemplate" TargetType="m:Pushpin">
<Grid x:Name="ContentGrid" Width="32" Height="32" Margin="0">
<Image Source="Resources/Pushpins/img.png" Stretch="Fill"/>
</Grid>
</ControlTemplate>
Then use it to a binded collection as follows:
<m:MapLayer x:Name="myPushpinLayer">
<m:MapItemsControl x:Name="myPushpins" ItemsSource="{Binding PushpinCollection}">
<m:MapItemsControl.ItemTemplate>
<DataTemplate>
<m:Pushpin Location="{Binding Location}" Template="{StaticResource PushpinTemplate}" />
</DataTemplate>
</m:MapItemsControl.ItemTemplate>
</m:MapItemsControl>
</m:MapLayer>
But what I want to be able to do is change the image source via a binding but am not sure how I go about doing this. What I was intending to do was to use a converter to change the image depending on an id within the collection if that alters the best way to do this.
Edit:
I got a little further:
<m:MapLayer x:Name="myPushpinLayer">
<m:MapItemsControl x:Name="myPushpins" ItemsSource="{Binding PushpinCollection}">
<m:MapItemsControl.ItemTemplate>
<DataTemplate>
<m:Pushpin Location="{Binding Location}"/>
<m:Pushpin.Template>
<ControlTemplate>
<Grid x:Name="ContentGrid" Width="32" Height="32" Margin="0">
<Image Source="{Binding Type,Converter={StaticResource ImageConverter}}" Stretch="Fill"/>
</Grid>
</ControlTemplate>
</m:Pushpin.Template>
</m:Pushpin>
</DataTemplate>
</m:MapItemsControl.ItemTemplate>
</m:MapItemsControl>
</m:MapLayer>
If I move the pushpin template into the </phone:PhoneApplicationPage.Resources> section then it fails. I am not sure why. I guess now I am trying to get to grips with my uinderstanding of how this all works
Just add the binding to the ControlTemplate
<ControlTemplate x:Key="PushpinTemplate" TargetType="m:Pushpin">
<Grid x:Name="ContentGrid" Width="32" Height="32" Margin="0">
<Image Source="{Binding ImageUri}" Stretch="Fill"/>
</Grid>
</ControlTemplate>
I would recommend a ImageUri (of type Uri) property that reflects what image to display, rather than using a converter. But a converter might also work, the bindings are done in the same way.