Visually Located

XAML and GIS

Disable screen capture for your Universal Windows apps

If you are concerned about security within your apps, you will want to disable the ability to taker screenshots of your app. This was a feature introduced in Windows Phone 8 as well as Windows Store 8.1 apps. With universal apps, you can now disable screenshots with the same one line of code Windows.UI.ViewManagement.ApplicationView.GetForCurrentView().IsScreenCaptureEnabled = false; This allows the application itself to not allow screenshots. So if you are running on desktop and you take a screen shot, the application will show black. Here is what it looks like on desktop with screen capture enabled Here is what it looks like on desktop with screen capture disabled I’m not able to get the phone emulator to take a physical screenshot (just the emulator screenshot) so I cannot show this. And until a new phone build comes out I cannot show it.

Persist ListView scroll position without setting NavigationCacheMode

Use the ListViewPersistenceHelper to persist the scroll position of a ListView in Windows apps. [More]

Animating list items within Windows apps

In a previous post I’ve talked about some page transitions and animations within Windows apps. There are many other locations where adding animations is very easy. One of these is animating items within any ItemsControl class. This includes controls like the ListView/GridView controls. The ItemsControl exposes the ItemContainerTransitions property. This property exposes a TransitionCollection, the same collection I talked about in the previous post. One of the key transitions you’ll want to look at is the EntranceThemeTransition. The EntranceThemeTransition defines how items will enter the region when they are rendered. It contains three properties. FromVerticalOffset and FromHorizontalOffset define the where the item should start rendering, with respect to where the final location will be. So if you have a FromVerticalOffset of 100, the item will begin an entrance animation 100 pixels below where it will end. The last property IsStaggeringEnabled, defines if all items should animate ... [More]

In depth look at the Windows RelativePanel

Windows 10 released a lot of new functionality and controls. One of the new controls is the RelativePanel. This panel takes the great Grid panel and cranks it up to 11. The Grid panel gives a lot of control with how you layout controls. You specify rows and columns of various heights and widths and then place controls within the grid and define the row and/or column through attached properties. Instead of rows/columns, the RelativePanel places controls relative to itself or other controls within it. Just like the Grid, the RelativePanel uses 16 different attached properties to define where elements should be placed. In fact, the RelativePanel has no additional properties or methods from a regular Panel. It only contains attached properties. Aligning relative to the RelativePanel The relative panel does not respect controls with traditional alignment via HorizontalAlignment and VerticalAlignment. Instead there are six new properties to define how an element should align relative to th... [More]

Creating different page views for Windows Apps based on the device

Windows 10 has released the new Universal App Platform that brings new “Windows Apps”. These apps offer the ability to use one Visual Studio project to create apps for any platform/device. This offers the ability to have one XAML file for all of your views. This works much like the web does with responsive design. If you want your page to look different on a smaller device you can change the layout based on the width of the device. You can do this with StateTriggers. <VisualStateManager.VisualStateGroups> <VisualStateGroup> <VisualState x:Name="wideState"> <VisualState.StateTriggers> <AdaptiveTrigger MinWindowWidth="600"/> </VisualState.StateTriggers> <VisualState.Setters> <Setter Target="MyTextBlock.Text" Value="BIGGER!" /> </VisualState.Setters> </VisualState> <VisualState x:Name="narrowState"> <VisualState... [More]

Registering to any DependencyProperty changing in Windows 10 Apps

Many have argued that there are pieces still missing from Windows Runtime XAML that were in WPF. One item that was in WPF was the ability to be notified when a DependencyProperty changed. This functionality is now available in Windows Apps thanks to the new RegisterProperrtyChangedCallback method on DependencyObject. This opens up a world of opportunities for us. This functionality is extremely useful when creating custom controls or wrapping existing controls. Rather than getting into anything complex, I’ll show a quick sample. A TextBlock control has Text, but no way to be notified when the text changes. We do have the ability to bind to the Text, but we’ll ignore that for now. We’ll create two TextBlocks and one Button. <StackPanel> <TextBlock x:Name="CounterText"/> <Button Content="Click me" Click="OnButtonClicked"/> <TextBlock x:Name="DuplicateTextBlock"/></StackPanel> When the button is clicked we’ll set the text for the first TextBlock... [More]

Enabling and tracking location in Windows Apps

Track geo location within Windows 10 Apps (preview) [More]