CollectionViewDataSource

Interface for providing data to a CollectionView.

The data source is responsible for:

• Reporting the total number of items
• Setting the size/position of each item frame
• Creating and configuring item views
• Managing view recycling

class MyDataSource implements CollectionViewDataSource {
    var items:Array<ItemData>;
    public function collectionViewSize(view:CollectionView):Int {
        return items.length;
    }
    public function collectionViewItemFrameAtIndex(view:CollectionView, index:Int, frame:CollectionViewItemFrame):Void {
        // Set item dimensions
        frame.width = 100;
        frame.height = 120;
    }
    public function collectionViewItemAtIndex(view:CollectionView, index:Int, reusableView:View):View {
        // Create or reuse a view
        var itemView = reusableView != null ? cast(reusableView, ItemView) : new ItemView();
        itemView.data = items[index];
        return itemView;
    }
    public function collectionViewReleaseItemAtIndex(view:CollectionView, index:Int, itemView:View):Bool {
        // Clean up and return true to allow reuse
        cast(itemView, ItemView).data = null;
        return true;
    }
}

Instance Members #

Returns the total number of items in the collection. This is called whenever the collection view needs to know how many items to display.

Sets the dimensions for an item at the specified index. The frame object should be modified with the desired width and height. Position (x, y) will be calculated by the layout.

Called when an item view is about to be recycled or removed. This allows cleanup of the view before it's reused for a different item.

Common cleanup tasks:

• Remove event listeners
• Cancel animations
• Clear references to prevent memory leaks

Creates or configures a view for the item at the specified index.

If reusableView is provided, it should be reconfigured for the new item to avoid creating new view instances. This improves performance.

The returned view will be automatically positioned and sized by the collection view based on the frame data.