// Property invalidation callback invoked when TemplateProperty is invalidated
private static void OnTemplateChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
ContentPresenter cp = (ContentPresenter)d;
UpdateTemplateCache(cp, (FrameworkTemplate)e.OldValue, (FrameworkTemplate)e.NewValue, TemplateProperty);
if (cp.IsConnectedToLiveTree)
{
cp.InvalidateMeasureInternal();
}
}
// Property invalidation callback invoked when TemplateProperty is invalidated
private static void OnTemplateChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
ContentPresenter cp = (ContentPresenter)d;
UpdateTemplateCache(cp, (FrameworkTemplate)e.OldValue, (FrameworkTemplate)e.NewValue, TemplateProperty);
if (VisualTreeHelper.GetParent(cp) != null)
{
cp.InvalidateMeasureInternal();
}
}
private static void OnContentChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
ContentPresenter ctrl = (ContentPresenter)d;
// if we're already marked to reselect the template, there's nothing more to do
if (!ctrl._templateIsCurrent)
{
return;
}
bool mismatch;
if (ctrl.ContentTemplate != null)
{
mismatch = false; // explicit template - do not re-apply
}
else if (ctrl.Template == UIElementContentTemplate)
{
mismatch = true; // direct template - always re-apply
ctrl.Template = null; // and release the old content so it can be re-used elsewhere
}
else if (ctrl.Template == DefaultContentTemplate)
{
mismatch = true; // default template - always re-apply
}
else
{
// implicit template - re-apply if content type changed
Type oldDataType = e.OldValue?.GetType();
Type newDataType = e.NewValue?.GetType();
mismatch = (oldDataType != newDataType);
}
// if the content and (old) template don't match, reselect the template
if (mismatch)
{
ctrl._templateIsCurrent = false;
}
// keep the DataContext in sync with Content
if (ctrl._templateIsCurrent && ctrl.Template != UIElementContentTemplate)
{
ctrl.DataContext = e.NewValue;
}
if (ctrl.IsConnectedToLiveTree)
{
ctrl.InvalidateMeasureInternal();
}
}
private static void OnContentTemplateChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
ContentPresenter ctrl = (ContentPresenter)d;
ctrl._templateIsCurrent = false;
// if ContentTemplate is really changing, remove the old template
ctrl.Template = null;
if (ctrl.IsConnectedToLiveTree)
{
ctrl.InvalidateMeasureInternal();
}
}
