/// <summary>
/// Initializes a new instance of the LinearLayoutManager class.
/// </summary>
/// <param name="isHorizontal">Layout orientation</param>
/// <param name="sizingStrategy">Item size measuring strategy</param>
/// <param name="itemSpacing">A space size between items</param>
#pragma warning disable CS8618
public LinearLayoutManager(bool isHorizontal, ItemSizingStrategy sizingStrategy, int itemSpacing)
#pragma warning restore CS8618
{
IsHorizontal = isHorizontal;
_hasUnevenRows = sizingStrategy == ItemSizingStrategy.MeasureAllItems;
ItemSpacing = itemSpacing;
}
public static T ItemSizingStrategy <T>(this T structuredElement, ItemSizingStrategy itemSizingStrategy)
where T : StructuredItemsView
{
structuredElement.ItemSizingStrategy = itemSizingStrategy;
return(structuredElement);
}
public GridLayoutManager(bool isHorizontal, int span, ItemSizingStrategy sizingStrategy, int verticalSpacing, int horizontalSpacing)
{
IsHorizontal = isHorizontal;
Span = span;
_hasUnevenRows = sizingStrategy == ItemSizingStrategy.MeasureAllItems;
VerticalItemSpacing = verticalSpacing;
HorizontalItemSpacing = horizontalSpacing;
}
public static TItemSizingStrategy ToPlatform(this ItemSizingStrategy itemSizingStrategy)
{
if (itemSizingStrategy == ItemSizingStrategy.MeasureAllItems)
{
return(TItemSizingStrategy.MeasureAllItems);
}
return(TItemSizingStrategy.MeasureFirstItem);
}
static void UpdateExplanation(Label explanation, ItemSizingStrategy strategy)
{
switch (strategy)
{
case ItemSizingStrategy.MeasureAllItems:
explanation.Text = "Each item is individually measured.";
break;
case ItemSizingStrategy.MeasureFirstItem:
explanation.Text = "The first item is measured, and that size is given to all subsequent cells.";
break;
}
}
protected ItemsViewLayout(ItemsLayout itemsLayout, ItemSizingStrategy itemSizingStrategy)
{
ItemSizingStrategy = itemSizingStrategy;
_itemsLayout = itemsLayout;
_itemsLayout.PropertyChanged += LayoutOnPropertyChanged;
var scrollDirection = itemsLayout.Orientation == ItemsLayoutOrientation.Horizontal
? UICollectionViewScrollDirection.Horizontal
: UICollectionViewScrollDirection.Vertical;
Initialize(scrollDirection);
if (Forms.IsiOS11OrNewer)
{
// `ContentInset` is actually the default value, but I'm leaving this here as a note to
// future maintainers; it's likely that someone will want a Platform Specific to change this behavior
// (Setting it to `SafeArea` lets you do the thing where the header/footer of your UICollectionView
// fills the screen width in landscape while your items are automatically shifted to avoid the notch)
SectionInsetReference = UICollectionViewFlowLayoutSectionInsetReference.ContentInset;
}
}
/// <summary>
/// Initializes a new instance of the LinearLayoutManager class.
/// </summary>
/// <param name="isHorizontal">Layout orientation</param>
/// <param name="sizingStrategy">Item size measuring strategy</param>
public LinearLayoutManager(bool isHorizontal, ItemSizingStrategy sizingStrategy) : this(isHorizontal, sizingStrategy, 0)
{
}
protected virtual ItemsViewLayout SelectLayout(IItemsLayout layoutSpecification, ItemSizingStrategy itemSizingStrategy)
{
if (layoutSpecification is GridItemsLayout gridItemsLayout)
{
return(new GridViewLayout(gridItemsLayout, itemSizingStrategy));
}
if (layoutSpecification is ListItemsLayout listItemsLayout)
{
return(new ListViewLayout(listItemsLayout, itemSizingStrategy));
}
// Fall back to vertical list
return(new ListViewLayout(new ListItemsLayout(ItemsLayoutOrientation.Vertical), itemSizingStrategy));
}
public static ICollectionViewLayoutManager ToLayoutManager(this IItemsLayout layout, ItemSizingStrategy sizing = ItemSizingStrategy.MeasureFirstItem)
{
switch (layout)
{
case LinearItemsLayout listItemsLayout:
return(new LinearLayoutManager(listItemsLayout.Orientation == ItemsLayoutOrientation.Horizontal, sizing, Forms.ConvertToScaledPixel(listItemsLayout.ItemSpacing)));
case GridItemsLayout gridItemsLayout:
return(new GridLayoutManager(gridItemsLayout.Orientation == ItemsLayoutOrientation.Horizontal,
gridItemsLayout.Span,
sizing,
Forms.ConvertToScaledPixel(gridItemsLayout.VerticalItemSpacing),
Forms.ConvertToScaledPixel(gridItemsLayout.HorizontalItemSpacing)));
default:
break;
}
return(new LinearLayoutManager(false));
}
public GridLayoutManager(bool isHorizontal, int span, ItemSizingStrategy sizingStrategy) : this(isHorizontal, span, sizingStrategy, 0, 0)
{
}
public GridLayoutManager(bool isHorizontal, int span, ItemSizingStrategy sizingStrategy)
{
IsHorizontal = isHorizontal;
Span = span;
_hasUnevenRows = sizingStrategy == ItemSizingStrategy.MeasureAllItems;
}
protected override ItemsViewLayout SelectLayout(IItemsLayout layoutSpecification, ItemSizingStrategy itemSizingStrategy)
{
if (layoutSpecification is ListItemsLayout listItemsLayout)
{
return(new CarouselViewLayout(listItemsLayout, itemSizingStrategy, CarouselView));
}
// Fall back to horizontal carousel
return(new CarouselViewLayout(new ListItemsLayout(ItemsLayoutOrientation.Horizontal), itemSizingStrategy, CarouselView));
}
public static T ItemSizingStrategy <T>(this T structureditemsview, ItemSizingStrategy itemSizingStrategy) where T : IRxStructuredItemsView
{
structureditemsview.ItemSizingStrategy = itemSizingStrategy;
return(structureditemsview);
}
public GridViewLayout(GridItemsLayout itemsLayout, ItemSizingStrategy itemSizingStrategy) : base(itemsLayout, itemSizingStrategy)
{
_itemsLayout = itemsLayout;
}
public CarouselViewLayout(ItemsLayout itemsLayout, ItemSizingStrategy itemSizingStrategy, CarouselView carouselView) : base(itemsLayout, itemSizingStrategy)
{
_carouselView = carouselView;
_itemsLayout = itemsLayout;
}
public static StructuredItemsView ItemSizingStrategy(this StructuredItemsView items, ItemSizingStrategy strategy)
{
items.ItemSizingStrategy = strategy;
return(items);
}
public ListViewLayout(LinearItemsLayout itemsLayout, ItemSizingStrategy itemSizingStrategy) : base(itemsLayout, itemSizingStrategy)
{
}
public LinearLayoutManager(bool isHorizontal, ItemSizingStrategy sizingStrategy)
{
IsHorizontal = isHorizontal;
_hasUnevenRows = sizingStrategy == ItemSizingStrategy.MeasureAllItems;
}
