private int VerifyRealizedRange(ItemsRepeater repeater, CustomItemsSource dataSource)
{
int numRealized = 0;
// trace
Log.Comment("index:ItemsSourceView:Item");
for (int i = 0; i < dataSource.Inner.Count; i++)
{
var element = repeater.TryGetElement(i);
if (element != null)
{
var data = ((TextBlock)element).Text;
Log.Comment("{0} {1}:[{2}]", i, dataSource.GetAt(i), data);
numRealized++;
}
else
{
Log.Comment(i + ":[null]");
}
}
// verify
for (int i = 0; i < dataSource.Inner.Count; i++)
{
var element = repeater.TryGetElement(i);
if (element != null)
{
var data = ((TextBlock)element).Text;
Verify.AreEqual(dataSource.GetAt(i).ToString(), data);
}
}
return(numRealized);
}
public void ValidateMappingAndAutoRecycling()
{
ItemsRepeater repeater = null;
ScrollViewer scrollViewer = null;
RunOnUIThread.Execute(() =>
{
var layout = new MockVirtualizingLayout()
{
MeasureLayoutFunc = (availableSize, context) =>
{
var element0 = context.GetOrCreateElementAt(index: 0);
// lookup - repeater will give back the same element and note that this element will not
// be pinned - i.e it will be auto recycled after a measure pass where GetElementAt(0) is not called.
var element0lookup = context.GetOrCreateElementAt(index: 0, options: ElementRealizationOptions.None);
var element1 = context.GetOrCreateElementAt(index: 1, options: ElementRealizationOptions.ForceCreate | ElementRealizationOptions.SuppressAutoRecycle);
// forcing a new element for index 1 that will be pinned (not auto recycled). This will be
// a completely new element. Repeater does not do the mapping/lookup when forceCreate is true.
var element1Clone = context.GetOrCreateElementAt(index: 1, options: ElementRealizationOptions.ForceCreate | ElementRealizationOptions.SuppressAutoRecycle);
Verify.AreSame(element0, element0lookup);
Verify.AreNotSame(element1, element1Clone);
element0.Measure(availableSize);
element1.Measure(availableSize);
element1Clone.Measure(availableSize);
return(new Size(100, 100));
},
};
Content = CreateAndInitializeRepeater(
itemsSource: Enumerable.Range(0, 5),
layout: layout,
elementFactory: GetDataTemplate("<Button>Hello</Button>"),
repeater: ref repeater,
scrollViewer: ref scrollViewer);
Content.UpdateLayout();
Verify.IsNotNull(repeater.TryGetElement(0));
Verify.IsNotNull(repeater.TryGetElement(1));
layout.MeasureLayoutFunc = null;
repeater.InvalidateMeasure();
Content.UpdateLayout();
Verify.IsNull(repeater.TryGetElement(0)); // not pinned, should be auto recycled.
Verify.IsNotNull(repeater.TryGetElement(1)); // pinned, should stay alive
});
}
public void ValidateDataContextGetsPropagated()
{
const string c_element1DataContext = "Element1_DataContext";
RunOnUIThread.Execute(() =>
{
var data = new List <Button>()
{
new Button()
{
Content = "Element1_Content",
DataContext = c_element1DataContext
}
};
var elementFactory = new ElementFromElementElementFactory();
var repeater = new ItemsRepeater()
{
ItemsSource = data,
ItemTemplate = elementFactory
};
Content = repeater;
Content.UpdateLayout();
// Verify that DataContext of data has propagated to the container
var firstElement = repeater.TryGetElement(0) as Button;
var retrievedDataContextItem1 = firstElement.DataContext as string;
Verify.IsTrue(data[0] == firstElement.Content);
Verify.IsTrue(retrievedDataContextItem1 == c_element1DataContext);
});
}
public void ValidateDataContextDoesNotGetOverwritten()
{
const string c_element1DataContext = "Element1_DataContext";
RunOnUIThread.Execute(() =>
{
var data = new List <Button>()
{
new Button()
{
Content = "Element1_Content",
DataContext = c_element1DataContext
}
};
var elementFactory = new DataAsElementElementFactory();
var repeater = new ItemsRepeater()
{
ItemsSource = data,
ItemTemplate = elementFactory
};
Content = repeater;
Content.UpdateLayout();
// Verify that DataContext is still the same
var firstElement = repeater.TryGetElement(0) as Button;
var retrievedDataContextItem1 = firstElement.DataContext as string;
Verify.IsTrue(retrievedDataContextItem1 == c_element1DataContext);
});
}
public void ValidateStackLayoutDisabledVirtualizationWithItemsRepeater()
{
RunOnUIThread.Execute(() =>
{
var repeater = new ItemsRepeater();
var stackLayout = new StackLayout();
stackLayout.DisableVirtualization = true;
repeater.Layout = stackLayout;
repeater.ItemsSource = Enumerable.Range(0, 10);
repeater.ItemTemplate = (DataTemplate)XamlReader.Parse(
@"<DataTemplate xmlns='http://schemas.microsoft.com/winfx/2006/xaml/presentation'>
<Button Content='{Binding}' Height='100' />
</DataTemplate>");
var scrollViewer = new ScrollViewer()
{
Content = repeater
};
scrollViewer.Height = 100;
Content = scrollViewer;
Content.UpdateLayout();
for (int i = 0; i < repeater.ItemsSourceView.Count; i++)
{
var child = repeater.TryGetElement(i) as Button;
Verify.IsNotNull(child);
}
});
}
public void ValidateNonVirtualLayoutWithItemsRepeater()
{
RunOnUIThread.Execute(() =>
{
var repeater = new ItemsRepeater();
repeater.Layout = new NonVirtualStackLayout();
repeater.ItemsSource = Enumerable.Range(0, 10);
repeater.ItemTemplate = (DataTemplate)XamlReader.Parse(
@"<DataTemplate xmlns='http://schemas.microsoft.com/winfx/2006/xaml/presentation'>
<Button Content='{Binding}' Height='100' />
</DataTemplate>");
Content = repeater;
Content.UpdateLayout();
double expectedYOffset = 0;
for (int i = 0; i < repeater.ItemsSourceView.Count; i++)
{
var child = repeater.TryGetElement(i) as Button;
Verify.IsNotNull(child);
var layoutBounds = LayoutInformation.GetLayoutSlot(child);
Verify.AreEqual(expectedYOffset, layoutBounds.Y);
Verify.AreEqual(i, child.Content);
expectedYOffset += 100;
}
});
}
public void CanResetLayoutAfterUniqueIdReset()
{
var data = new WinRTCollection(Enumerable.Range(0, 2).Select(i => string.Format("Item #{0}", i)));
object dataSource = null;
RunOnUIThread.Execute(() => dataSource = MockItemsSource.CreateDataSource(data, supportsUniqueIds: true));
ItemsRepeater repeater = SetupRepeater(dataSource);
RunOnUIThread.Execute(() =>
{
var range = new UIElement[] { repeater.TryGetElement(0), repeater.TryGetElement(1) };
var clearedElements = new List <UIElement>();
repeater.ElementClearing += (s, e) =>
{
clearedElements.Add(e.Element);
};
// The realized elements will be sent to the unique id reset pool.
// They haven't been cleared yet.
data.Reset();
Verify.AreEqual(0, clearedElements.Count);
// This also cause elements to be sent to the unique id reset pool.
// We are validating here that we are smart enough not send them there twice.
// Doing so will cause an exception to be thrown.
repeater.Layout = null;
Verify.AreEqual(0, clearedElements.Count);
repeater.UpdateLayout();
// Layout runs. The elements in the reset pool are not used.
// They should be cleared back to the view generator at this point.
Verify.AreEqual(2, clearedElements.Count);
Verify.AreEqual(range[0], clearedElements[0]);
Verify.AreEqual(range[1], clearedElements[1]);
Verify.IsNull(repeater.TryGetElement(0));
Verify.IsNull(repeater.TryGetElement(1));
});
}
public void CanChangeFocusAfterUniqueIdReset()
{
var data = new WinRTCollection(Enumerable.Range(0, 2).Select(i => string.Format("Item #{0}", i)));
object dataSource = null;
RunOnUIThread.Execute(() => dataSource = MockItemsSource.CreateDataSource(data, supportsUniqueIds: true));
ItemsRepeater repeater = SetupRepeater(dataSource);
Control focusedElement = null;
RunOnUIThread.Execute(() =>
{
focusedElement = (Control)repeater.TryGetElement(0);
focusedElement.Focus();
});
IdleSynchronizer.Wait();
RunOnUIThread.Execute(() =>
{
data.Reset();
});
IdleSynchronizer.Wait();
RunOnUIThread.Execute(() =>
{
// Still focused.
Verify.AreEqual(focusedElement, Keyboard.FocusedElement);
// Change focused element.
focusedElement = (Control)repeater.TryGetElement(1);
focusedElement.Focus();
});
IdleSynchronizer.Wait();
RunOnUIThread.Execute(() =>
{
// Focus is on the new element.
Verify.AreEqual(focusedElement, Keyboard.FocusedElement);
});
}
private VirtualizingLayout CreateLayout(ItemsRepeater repeater)
{
var layout = new MockVirtualizingLayout();
var children = new List <UIElement>();
layout.MeasureLayoutFunc = (availableSize, context) =>
{
repeater.Tag = repeater.Tag ?? context;
children.Clear();
var itemCount = context.ItemCount;
for (int i = 0; i < itemCount; ++i)
{
var element = repeater.TryGetElement(i) ?? context.GetOrCreateElementAt(i);
element.Measure(availableSize);
children.Add(element);
}
return(new Size(10, 10));
};
return(layout);
}
private void MoveFocusToIndex(ItemsRepeater repeater, int index)
{
var element = repeater.TryGetElement(index) as Control;
element.Focus();
}
// [TestMethod] Issue 1018
public void CanReuseElementsDuringUniqueIdReset()
{
var data = new WinRTCollection(Enumerable.Range(0, 2).Select(i => string.Format("Item #{0}", i)));
List <UIElement> mapping = null;
ItemsRepeater repeater = null;
MockElementFactory elementFactory = null;
ContentControl focusedElement = null;
RunOnUIThread.Execute(() =>
{
mapping = new List <UIElement> {
new ContentControl(), new ContentControl()
};
repeater = CreateRepeater(
MockItemsSource.CreateDataSource(data, supportsUniqueIds: true),
MockElementFactory.CreateElementFactory(mapping));
elementFactory = (MockElementFactory)repeater.ItemTemplate;
Content = repeater;
repeater.UpdateLayout();
focusedElement = (ContentControl)repeater.TryGetElement(1);
focusedElement.Focus();
});
IdleSynchronizer.Wait();
RunOnUIThread.Execute(() =>
{
elementFactory.ValidateGetElementCalls(
new MockElementFactory.GetElementCallInfo(0, repeater),
new MockElementFactory.GetElementCallInfo(1, repeater));
elementFactory.ValidateRecycleElementCalls();
data.ResetWith(new[] { data[0], "New item" });
Verify.AreEqual(0, repeater.GetElementIndex(mapping[0]));
Verify.AreEqual(1, repeater.GetElementIndex(mapping[1]));
Verify.IsNull(repeater.TryGetElement(0));
Verify.IsNull(repeater.TryGetElement(1));
elementFactory.ValidateGetElementCalls(/* GetElement should not be called */);
elementFactory.ValidateRecycleElementCalls(/* RecycleElement should not be called */);
mapping[1] = new ContentControl(); // For "New Item"
repeater.UpdateLayout();
Verify.AreEqual(0, repeater.GetElementIndex(mapping[0]));
Verify.AreEqual(1, repeater.GetElementIndex(mapping[1]));
Verify.AreEqual(mapping[0], repeater.TryGetElement(0));
Verify.AreEqual(mapping[1], repeater.TryGetElement(1));
elementFactory.ValidateGetElementCalls(
new MockElementFactory.GetElementCallInfo(1, repeater));
elementFactory.ValidateRecycleElementCalls(
new MockElementFactory.RecycleElementCallInfo(focusedElement, repeater));
// If the focused element survived the reset, we will keep focus on it. If not, we
// try to find one based on the index. In this case, the focused element (index 1)
// got recycled, and we still have index 1 after the stable reset, so the new index 1
// will get focused. Note that recycling the elements to view generator in the case of
// stable reset happens during the arrange, so by that time we will have pulled elements
// from the stable reset pool and maybe created some new elements as well.
int index = repeater.GetElementIndex(focusedElement);
Log.Comment("focused index " + index);
Verify.AreEqual(mapping[1], Keyboard.FocusedElement);
});
}
private void ValidateRealizedRange(
ItemsRepeater repeater,
int expectedFirstGroupIndex,
int expectedLastGroupIndex,
int expectedFirstItemGroupIndex,
int expectedFirstItemIndex,
int expectedLastItemGroupIndex,
int expectedLastItemIndex)
{
int actualFirstGroupIndex = -1;
int actualLastGroupIndex = -1;
int actualFirstItemGroupIndex = -1;
int actualFirstItemIndex = -1;
int actualLastItemGroupIndex = -1;
int actualLastItemIndex = -1;
RunOnUIThread.Execute(() =>
{
int groupIndex = 0;
int itemIndex = 0;
var groups = (IEnumerable <NamedGroup <string> >)repeater.ItemsSource;
foreach (var group in groups)
{
var groupElement = repeater.TryGetElement(groupIndex);
if (groupElement != null)
{
actualFirstGroupIndex =
actualFirstGroupIndex == -1 ?
groupIndex :
actualFirstGroupIndex;
actualLastGroupIndex = groupIndex;
var innerRepeater = (ItemsRepeater)((FrameworkElement)groupElement).FindName("InnerRepeater");
foreach (var item in group)
{
var itemElement = innerRepeater.TryGetElement(itemIndex);
if (itemElement != null)
{
actualFirstItemGroupIndex =
actualFirstItemGroupIndex == -1 ?
groupIndex :
actualFirstItemGroupIndex;
actualFirstItemIndex =
actualFirstItemIndex == -1 ?
itemIndex :
actualFirstItemIndex;
actualLastItemGroupIndex = groupIndex;
actualLastItemIndex = itemIndex;
}
++itemIndex;
}
}
itemIndex = 0;
++groupIndex;
}
});
Verify.AreEqual(expectedFirstGroupIndex, actualFirstGroupIndex);
Verify.AreEqual(expectedLastGroupIndex, actualLastGroupIndex);
Verify.AreEqual(expectedFirstItemGroupIndex, actualFirstItemGroupIndex);
Verify.AreEqual(expectedFirstItemIndex, actualFirstItemIndex);
Verify.AreEqual(expectedLastItemGroupIndex, actualLastItemGroupIndex);
Verify.AreEqual(expectedLastItemIndex, actualLastItemIndex);
}