I using silverlight in my siverlight page I want to disable all the controls.
I want to disable the entire page instead disabling the individual control.
Here goes the Answer..
<ContentControl x:Name="GroupOfControls" >
<Grid x:Name="LayoutRoot" Background="White">
'Design your own controls
</Grid>
</ContentControl>
Insert your Grid in the content control then
you can enable or disable all the controls on the silverlight page
GroupOfControls.IsEnabled = False
GroupOfControls.IsEnabled = True
Setting the IsEnabled property to false of the parent control should disable child controls.
http://msdn.microsoft.com/en-us/library/system.windows.controls.control.isenabled(v=vs.95).aspx
Related
In the Universal Windows Platform API, how do I use x:Bind inside of a User Control (intended to be the layout for a GridView's ItemTemplate) to bind to instance properties of a GridView's ItemSource?
Background
I'm trying to re-create the layout found in Windows 10 stock apps like Sports, News, Money, etc.
I'm using a two GridViews for the main area of the app; one for "featured articles" (2 large photos w/ headlines) and one for all the other articles (smaller photos w/ headlines).
I'm able to bind to a data source that I supply in the code behind (a List where NewsItem is a POCO with a Image and Headline property) Here's the pertinent parts of the MainPage.xaml:
<Page ...
xmlns:data="using:NewsApp.Models" />
....
<GridView Name="FeaturedItems" Grid.Row="0">
<GridView.ItemTemplate>
<DataTemplate x:DataType="data:NewsItem">
<Grid Name="mainPanel" HorizontalAlignment="Stretch" Width="500" >
<Image Source="{x:Bind Image}" HorizontalAlignment="Stretch" />
<TextBlock Text="{x:Bind Headline}" />
</Grid>
</DataTemplate>
</GridView.ItemTemplate>
</GridView>
....
The Image and Headline bind just fine (even though they've not been styled correctly). However, instead I think I need to bind to a User Control to get the styling options I want, control over resizing esp. when using Visual State Triggers and to simplify the XAML in general (at least, this was the technique suggested to me.)
So, I added a new User Control to the project (FeaturedItemControl.xaml), and copied in the DataTemplate's child Grid:
<UserControl ... >
<Grid Name="mainPanel" HorizontalAlignment="Stretch" Width="500" >
<Image Source="{x:Bind Image}" HorizontalAlignment="Stretch" />
<TextBlock Text="{x:Bind Headline}" />
</Grid>
</UserControl>
And then back in the MainPage.xaml, I change the DataTemplate to reference the new FeaturedItemControl:
<GridView Name="FeaturedItems" Grid.Row="0">
<GridView.ItemTemplate>
<DataTemplate x:DataType="data:NewsItem">
<local:FeaturedItemControl HorizontalAlignment="Stretch" VerticalAlignment="Stretch" />
</DataTemplate>
</GridView.ItemTemplate>
</GridView>
However, I get the error message for both Image and Headline properties: Invalid binding path 'Headline': Property 'Headline' can't be found on type 'FeaturedItemControl'.
I've tried a few things but am flailing just throwing code at the problem without understanding what I'm doing. Any help would be greatly appreciated.
Thank you for your kind attention.
Using Depechie's answer, I formulated this little cheat cheat for posterity:
Do note that you MUST use this technique to utilize the VisualStateManager with items inside your data bound controls' (GridView, ListView) data templates.
1) Create a User Control.
2) Cut the content of the DataTemplate in your page and paste it into the User Control replacing the template's Grid.
3) Reference the User Control from inside the Data Template:
4) Modify the contents of the User Control changing x:Bind statements to utilize object.property notation:
<UserControl>
<StackPanel>
<Image Source="{x:Bind NewsItem.LeadPhoto}" />
<TextBlock Text="{x:Bind NewsItem.Headline}" />
<TextBlock Text="{x:Bind NewsItem.Subhead}" />
</StackPanel>
</UserControl>
5) Add this in the User Control's Code Behind:
public Models.NewsItem NewsItem { get { return this.DataContext as Models.NewsItem; } }
public ContactTemplate()
{
this.InitializeComponent();
this.DataContextChanged += (s, e) => Bindings.Update();
}
Well it's possible to use x:Bind in user controls, but you'll need to add some extra code behind.
I encountered the same problem in my project, you can see the result here : https://github.com/AppCreativity/Kliva/tree/master/src/Kliva/Controls
So what you need to do is, create a property in the code behind of your user control that points to the correct DataContext.
If you do that, you can use properties of that DataContext in the xaml of your control: for example:
Do note that in the constructor of your control you do need to add: DataContextChanged += (sender, args) => this.Bindings.Update(); because the datacontext will change depending on the page where your control is used!
Then on the page where you are placing this control, you'll also need to do the same to enable the x:bind to work.
You'll see this in my example on the MainPage.DeviceFamily-Mobile.xaml and MainPage.xaml.cs files.
Hope this helps.
x:Bind isn't really hierarchical like Binding/DataContext is. Additionally when you're not directly inside a DataTemplate (such as inside your user control) the object that x:Bind tries to use is 'this' rather than 'this.DataContext'. My current line of thinking on how to solve this sort of issue is to try not to use UserControls anywhere. Instead preferring DataTemplates contained within a ResourceDictionary. There are some pretty strong caveats to this approach though, you will for example crash the xaml compiler if you use x:Bind inside a data template that was created from the ResourceDictionary item template (add new item). you can find a pretty complete example here https://github.com/Microsoft/Windows-universal-samples/tree/master/Samples/XamlBind its important to note in the sample where they show the ResourceDictionary being used that its not actually just a ResourceDictionary.xaml its also a ResourceDictionary.xaml.cs (this is where the generated code from x:Bind ends up)
Another option is to add Headline and Image as properties on your user control and x:Bind them from the template, then inside the user control x:Bind as you are currently doing, but now the x:Bind generated path 'this.Headline' will exist. Unfortunately the order things are actually bound means that the x:Bind's you have inside your user control will have to be OneWay rather than the default OneTime. this is because x:Bind OneTime does the bind inside the InitializeComponent call, and any set of properties/DataContext stuff doesn't get done until after that has already run.
So to sum this up, you have two options, use data templates everywhere, or bind to properties that are directly on the user control.
I am trying to design a simple tabbed app using universal windows platform (UWP) using Pivot control.
I have customized header that includes other controls than just a textblock. I am targeting to change color of those controls/graphics on selection of particular PivotItem using triggers in xaml. Default color updates on selection & hover only apply on textblock but not on other controls.
I can try binding color of other controls with forecolor of textblock because I cannot find template binding not control template in UWP xaml. binding with textblock will still give less space for customization as I am targeting AccentColor for header controls/graphics which are defined by MSFT in UAP sdk and we can access them as static resource from generic.xaml. e.g. SystemControlBackgroundAccentBrush. I looked in to xaml triggers as MSFT new xaml architecture allows us to define VisualStateGroups and work using AdaptiveTriggers & StateTrigger. I can't find any other type of triggers like datatriggers, eventtriggers nothing...
<PivotItem>
<PivotItem.Header>
<StackPanel Orientation="Horizontal">
<Path Stretch="Uniform"
Fill="{StaticResource PivotForegroundThemeBrush}"
Width="32pt"
Height="32pt"
Data="M0,33.893959L4.4794149,33.893959 4.4794149,44.677959 48.903614,44.677959 48.903614,33.893959 53.333035,33.893959 53.333035,49.104958 0,49.104958z M24.842734,0L28.513577,0 28.513577,24.615005 35.345016,17.78297 40.346104,17.78297 40.436089,17.883007 26.673088,31.644001 24.072548,29.047991 12.910089,17.883007 13.010208,17.78297 18.001283,17.78297 24.842734,24.615005z"/>
<TextBlock Text="Downloads"
VerticalAlignment="Center" Margin="5"
FontSize="{StaticResource PivotHeaderItemFontSize}"/>
</StackPanel>
</PivotItem.Header>
<Grid></Grid>
</PivotItem>
I'm new to Windows Phone apps development, and I've created a scrolling menu using the following xaml code :
<ScrollViewer HorizontalAlignment="Left" Margin="18,0,0,0" Name="scrollViewer1" VerticalAlignment="Top" Width="450" HorizontalScrollBarVisibility="Auto" Grid.Row="1">
<StackPanel Height="Auto" Name="stackPanel1" Width="Auto">
<Button Height="620" FontSize="120" Name="gotoGmail" Width="Auto">Gmail</Button>
<Button Height="620" FontSize="120" Name="gotoYahoo" Width="Auto">Yahoo</Button>
</StackPanel>
</ScrollViewer>
I'd like to know whether it's possible to start an event once the user scrolls the menu from one button to another. If it is possible, i'd be grateful if you could explain how. If it's not , i'd like to hear about how could I do it using different tools rather than ScrollViewer. Thanks in advance !
There's no "Scrolled" event on the ScrollViewer, but what you can do is two-way bind a property to VerticalOffset. That lets you trigger an event/command from your view/viewmodel when the scroll changes.
Something like this:
<ScrollViewer VerticalOffset="{Binding VerticalOffset,Mode=TwoWay}" ...
And then in the data context:
public double VerticalOffset
{
get { return _verticalOffset; }
set
{
_verticalOffset = value;
// call "on scroll changed" actions here
}
}
private double _verticalOffset = 0;
how could I do it using different tools rather than ScrollViewer
You can of course make a scrolling menu using other approaches. I'll bet there is some nifty approach you could figure, using the WinRT transitions/animations stuff, but I'm not familiar enough with those to say. Here are some others (not sure which would be best/easiest for your scenario):
Probably using Canvas would be a quick-and-dirty way to do it (just set up buttons that set off Canvas.Left and Canvas.Top animations).
Extending ItemsControl along with a custom ControlTemplate would be a good approach if you want to create a re-usable component.
I like extending Panel, but you have to do the animations manually using a DispatcherTimer, and you have to lay out the buttons yourself using Measure and Arrange.
Simpel question, I have a windows phone page that contains a scrollviewer with inside it an image, a textblock and a richtextbox.
Now when the user starts scrolling I want to keep the textblock in view on top when the image has scrolled outside the page.
So the effect is, user starts scrolling upwards, everything scrolls upwards, when the image is outside the page, the textblock stays at the top of the page but the richtextbox keeps scrolling upwards.
Any thoughts?
Here is a way to reach this result:
First, the layout. I've set a grid, with two rows. The first is empty, and will host the header when we need to freeze it. The second row contains the scrollviewer.
Inside the scrollviewer, I've put the controls in a grid, but you can use whatever container suits you.
<ScrollViewer Grid.Row="1"
Margin="0"
Padding="0"
x:Name="ParentScroll"
ManipulationMode="Control"
MouseMove="ParentScroll_MouseMove">
<Grid x:Name="ChildGrid">
<Grid.RowDefinitions>
<RowDefinition Height="Auto" />
<RowDefinition Height="Auto" />
<RowDefinition />
</Grid.RowDefinitions>
<Image Source="Picture.jpg" Grid.Row="0"/>
<TextBlock Text="Header" Grid.Row="1" x:Name="TextHeader" />
<RichTextBox Grid.Row="2" x:Name="RichText">
<Paragraph>
<Bold>RichTextBox</Bold>
<!-- More stuff -->
</Paragraph>
</RichTextBox>
</Grid>
</ScrollViewer>
I use the MouseMove event to be notified of the scrolling event. You can also dig into the template, extract the ScrollBar control, and subscribe to the ValueChanged event, as described here: http://social.msdn.microsoft.com/Forums/wpapps/en-US/81fcd34e-6ec9-48d0-891e-c53a53344553/scrollviewer-synchronization
Note that you need to set ManipulationMode to Control or the position of the controls won't be updated at a smooth rate. I guess it's due to some internal optimization.
In the code behind, I use the TransformToVisual method to compute the relative position of the controls to the ScrollViewer. This way, I can know when the header goes out of view. When it does, I remove it from the child grid, and put it outside of the ScrollViewer, in the parent grid. When the top of the RichTextBox goes out of view, I put the header back into the ScrollViewer:
private void ParentScroll_MouseMove(object sender, System.Windows.Input.MouseEventArgs e)
{
if (Grid.GetRow(this.TextHeader) == 1)
{
var generalTransform = TextHeader.TransformToVisual(ParentScroll);
var childToParentCoordinates = generalTransform.Transform(new Point(0, 0));
if (childToParentCoordinates.Y < 0)
{
this.ChildGrid.Children.Remove(this.TextHeader);
this.ParentGrid.Children.Add(this.TextHeader);
Grid.SetRow(this.TextHeader, 0);
}
}
else
{
var generalTransform = RichText.TransformToVisual(ParentScroll);
var childToParentCoordinates = generalTransform.Transform(new Point(0, 0));
if (childToParentCoordinates.Y > 0)
{
this.ParentGrid.Children.Remove(this.TextHeader);
this.ChildGrid.Children.Add(this.TextHeader);
Grid.SetRow(this.TextHeader, 1);
}
}
There may be less-hacky ways to reach the same results, but this solution seems to work smoothly in the emulator.
I've found a working solution myself... the complete detail is available on my blog here... it contains also the link to my demo project on GitHub.
The trick was to get hold of the VerticallScrollBar inside the ScrollViewer and to set the ManipulationMode to Control to get enough feedback on the UI thread.
With the scroll offset information of the scrollbar we than animate the specific ui element we want to keep in view.
I Have a ListBox and I am defining its ItemsTemplate using a custom control. I want the control to be displayed in different ways depending on the state of cetain properties of the object. How can I access the item that the ListBox.ItemTemplate is bound to?
<ListBox>
<ListBox.ItemTemplate>
<DataTemplate>
<custom:MyControl />
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
With in the code of the custom control how would I do something like:
if((this.DataContext as SomeObject).CollectionProperty.Count() > 0)
DoAction();
I was accessing dataContext in the constructor and it was null. I accessed it in the this.Loaded event and it worked fine.