ScrollViewPager Class - Fuse Documentation

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This entity is experimental and might be changed or removed in a future release.

Paging and loading manager for a list of items. Allows a large, or infinite list, to be displayed in a ScrollView.

This controls the Offset and Limit properties of an Each inside a ScrollView. It limits the number of items displayed to improve performance.

The setup that works now is with a StackPanel (Horizontal or Vertical)

<ScrollView LayoutMode="PreserveVisual">
    <StackPanel>
        <Each Items="{items}" Reuse="Frame" ux:Name="theEach">
            <Panel Color="#AAA">
                <Text Value="{title}"/>
            </Panel>
        </Each>
    </StackPanel>

    <ScrollViewPager Each="theEach" ReachedEnd="{loadMore}"/>
</ScrollView>

It's required to use LayoutMode="PreserveVisual", otherwise the scrolling will not function correctly. Reuse="Frame" is optional but recommended: it improves performance by reusing objects.

ReachedEnd is called when the true end of the list is reached and more data is required. It's actually called somewhat before the end is reached, thus allowing the loading process to start before the user reaches the end. There is also a RechedStart to allow loading when scrolling the opposite direction. Neither of these callbacks are mandatory; ScrollViewPager is also helpful for displaying large static lists.

Location

Namespace: Fuse.Controls
Package: Fuse.Controls.ScrollView 2.9.1

Show Uno properties and methods

Interface of ScrollViewPager

Check uno

Should be called whenever new data is added in response to ReachedEnd or ReachedStart. This will ensure the paging is updated even when nothing else would trigger the update.

Each : Each ux

The Each instance to control. This property is required.

EndRange : float ux

ReachedEnd : ScrollViewPagerHandler (object, ScrollViewPagerArgs) ux

Raised when the ScrollView comes near the end of the data.

ReachedStart : ScrollViewPagerHandler (object, ScrollViewPagerArgs) ux

Raised when the ScrollView comes near the start of the data.

Retain : int ux

An approximate number of pages to retain. The size of the visible part of the ScrollView is the page size. Enough items to fill multiple amounts of this size are kept around. The rest are discarded.

ScrollViewPager Constructor uno

Creates a new ScrollViewPager

Step : int ux

The step value for increasing or decreasing Offset/Limit property of the Each

Inherited from Node

Add(Binding) uno

Bindings : IList of Binding ux

The list of bindings belonging to this node.

ContextParent : Node uno

The context parent is the semantic parent of this node. It is where non-UI structure should be resolved, like looking for the DataContext, a Navigation, or other semantic item.

FindByType<T> : T uno

FindNodeByName(Selector, Predicate<Node> (Node)) : Node uno

Finds the first node with a given name that satisfies the given acceptor. The serach algorithm works as follows: Nodes in the subtree are matched first, then it matches the nodes in the subtrees ofthe ancestor nodes by turn all the way to the root. If no matching node is found, the function returns null.

GetNearestAncestorOfType<T> : T uno

Insert(int, Binding) uno

IsRootingCompleted : bool uno

Whether rooting for this node is completed. Returns false if unrooting has started.

IsRootingStarted : bool uno

Whether rooting of this node has started. Note that even if this property returns true, rooting may not yet be completed for the node. See also IsRootingCompleted.

Name : Selector ux

Run-time name of the node. This property is automatically set using the ux:Name attribute.

NextSibling<T> : T uno

Returns the next sibling node of the given type.

OnDataChanged(string, object) uno

OnRooted uno

If you override OnRooted you must call base.OnRooted() first in your derived class. No other processing should happen first, otherwise you might end up in an undefined state.