public void When_ObservableVectorStringChanged()
{
var count = 0;
var containerCount = 0;
var panel = new StackPanel();
panel.ForceLoaded();
var source = new ObservableVector <string>()
{
"1", "2", "3"
};
Style BuildContainerStyle() =>
new Style(typeof(Windows.UI.Xaml.Controls.ListViewItem))
{
Setters =
{
new Setter <ContentControl>("Template", t =>
t.Template = Funcs.Create(() => {
containerCount++;
return(new Grid
{
Children =
{
new ContentPresenter()
.Apply(p => {
p.SetBinding(ContentPresenter.ContentTemplateProperty, new Binding()
{
Path = "ContentTemplate", RelativeSource = RelativeSource.TemplatedParent
});
p.SetBinding(ContentPresenter.ContentProperty, new Binding()
{
Path = "Content", RelativeSource = RelativeSource.TemplatedParent
});
})
}
});
})
)
}
};
var SUT = new ListView()
{
ItemsPanelRoot = panel,
InternalItemsPanelRoot = panel,
ItemContainerStyle = BuildContainerStyle(),
ItemTemplate = new DataTemplate(() =>
{
count++;
return(new Border());
})
};
Assert.AreEqual(0, count);
Assert.AreEqual(0, containerCount);
Assert.AreEqual(0, containerCount);
SUT.ItemsSource = source;
Assert.AreEqual(3, count);
Assert.AreEqual(3, containerCount);
Assert.AreEqual(3, containerCount);
source.Add("4");
Assert.AreEqual(4, count);
Assert.AreEqual(4, containerCount);
Assert.AreEqual(4, containerCount);
source.Remove("1");
Assert.AreEqual(4, count);
Assert.AreEqual(4, containerCount);
Assert.AreEqual(4, containerCount);
source[0] = "5";
// Data template is not recreated because of pooling
Assert.AreEqual(4, count);
// The item container style is reapplied (not cached)
Assert.AreEqual(5, containerCount);
}
