/// <summary>
/// Sets the content of the test app to a simple <see cref="FrameworkElement"/> to load into the visual tree.
/// Waits for that element to be loaded and rendered before returning.
/// </summary>
/// <param name="content">Content to set in test app.</param>
/// <returns>When UI is loaded.</returns>
protected Task SetTestContentAsync(FrameworkElement content)
{
return(App.DispatcherQueue.EnqueueAsync(() =>
{
var taskCompletionSource = new TaskCompletionSource <bool>();
async void Callback(object sender, RoutedEventArgs args)
{
content.Loaded -= Callback;
// Wait for first Render pass
await CompositionTargetHelper.ExecuteAfterCompositionRenderingAsync(() => { });
taskCompletionSource.SetResult(true);
}
// Going to wait for our original content to unload
content.Loaded += Callback;
// Trigger that now
try
{
App.ContentRoot = content;
}
catch (Exception e)
{
taskCompletionSource.SetException(e);
}
return taskCompletionSource.Task;
}));
}
private void GuardAgainstPlaceholderTextLayoutIssue()
{
// If the *PlaceholderText is visible* on the last AutoSuggestBox, it can incorrectly layout itself
// when the *ASB has focus*. We think this is an optimization in the platform, but haven't been able to
// isolate a straight-reproduction of this issue outside of this control (though we have eliminated
// most Toolkit influences like ASB/TextBox Style, the InterspersedObservableCollection, etc...).
// The only Toolkit component involved here should be WrapPanel (which is a straight-forward Panel).
// We also know the ASB itself is adjusting it's size correctly, it's the inner component.
//
// To combat this issue:
// We toggle the visibility of the Placeholder ContentControl in order to force it's layout to update properly
var placeholder = ContainerFromItem(_lastTextEdit)?.FindDescendant("PlaceholderTextContentPresenter");
if (placeholder?.Visibility == Visibility.Visible)
{
placeholder.Visibility = Visibility.Collapsed;
// After we ensure we've hid the control, make it visible again (this is imperceptible to the user).
_ = CompositionTargetHelper.ExecuteAfterCompositionRenderingAsync(() =>
{
placeholder.Visibility = Visibility.Visible;
});
}
}
public async Task Test_ConstrainedBox_Combined_All()
{
await App.DispatcherQueue.EnqueueAsync(async() =>
{
// We turn LayoutRounding off as we're doing between pixel calculation here to test.
var treeRoot = XamlReader.Load(@"<Page
xmlns=""http://schemas.microsoft.com/winfx/2006/xaml/presentation""
xmlns:x=""http://schemas.microsoft.com/winfx/2006/xaml""
xmlns:controls=""using:Microsoft.Toolkit.Uwp.UI.Controls"">
<Grid x:Name=""ParentGrid"" Width=""100"" Height=""100"">
<controls:ConstrainedBox x:Name=""ConstrainedBox"" ScaleX=""0.9"" ScaleY=""0.9""
MultipleX=""32"" MultipleY=""32""
AspectRatio=""3:1""
UseLayoutRounding=""False""
HorizontalAlignment=""Stretch"" VerticalAlignment=""Stretch"">
<Border HorizontalAlignment=""Stretch"" VerticalAlignment=""Stretch"" Background=""Red""/>
</controls:ConstrainedBox>
</Grid>
</Page>") as FrameworkElement;
Assert.IsNotNull(treeRoot, "Could not load XAML tree.");
// Initialize Visual Tree
await SetTestContentAsync(treeRoot);
var grid = treeRoot.FindChild("ParentGrid") as Grid;
var panel = treeRoot.FindChild("ConstrainedBox") as ConstrainedBox;
Assert.IsNotNull(panel, "Could not find ConstrainedBox in tree.");
// Force Layout calculations
panel.UpdateLayout();
var child = panel.Content as Border;
Assert.IsNotNull(child, "Could not find inner Border");
// Check Size
Assert.AreEqual(64, child.ActualWidth, 0.01, "Actual width does not meet expected value of 64");
Assert.AreEqual(21.333, child.ActualHeight, 0.01, "Actual height does not meet expected value of 21.33");
// Check inner Positioning, we do this from the Grid as the ConstainedBox also modifies its own size
// and is hugging the child.
var position = grid.CoordinatesTo(child);
Assert.AreEqual(18, position.X, 0.01, "X position does not meet expected value of 18");
Assert.AreEqual(39.333, position.Y, 0.01, "Y position does not meet expected value of 39.33");
// Update Aspect Ratio and Re-check
panel.AspectRatio = new AspectRatio(1, 3);
// Wait to ensure we've redone layout
await CompositionTargetHelper.ExecuteAfterCompositionRenderingAsync(() =>
{
// Check Size
Assert.AreEqual(21.333, child.ActualWidth, 0.01, "Actual width does not meet expected value of 21.33");
Assert.AreEqual(64, child.ActualHeight, 0.01, "Actual height does not meet expected value of 64");
// Check inner Positioning, we do this from the Grid as the ConstainedBox also modifies its own size
// and is hugging the child.
position = grid.CoordinatesTo(child);
Assert.AreEqual(39.333, position.X, 0.01, "X position does not meet expected value of 39.33");
Assert.AreEqual(18, position.Y, 0.01, "Y position does not meet expected value of 18");
});
});
}
