PullToReload Class

Helps you create a "pull to reload" interaction with a ScrollView.

It is implemented as a ScrollingAnimation, with a set of properties that let you bind different states that should be triggered during different stages of interaction:

  • Pulling - Active when the user is actively pulling down beond the top of the content

  • PulledPastThreshold - Active when the user has pulled down enough to activate loading

  • Loading - Active when the "loading" has started. Loading starts when the user has pulled past the threshold, and then leaves the threshold area.

  • Rest - Active when the user has pulled down the content, but their last movement was upwards. In addition, you have a callback, ReloadHandler, which is called when the Loading state activates.

  • Note that PullToReload inherits from ScrollingAnimation and therefore can be tweaked further using its properties. Here is an example of how we can tweak it to be pulled from the bottom instead using the Range property from ScrollingAnimation:

<PullToReload Range="SnapMax">
    ...
</PullToReload>

See the Pull to reload, for a complete example on how to use it.

Example

The following example flashes the app background in different colors as the different states of the PullToReload happen:

<ScrollView>
    <PullToReload>
        <Timeline ux:Name="redFlash">
            <Change color.Color="#F00" Duration="1"/>
        </Timeline>
        <Timeline ux:Name="pinkFlash">
            <Change color.Color="#FFC0DB" Duration="1"/>
        </Timeline>
        <Timeline ux:Name="greenFlash">
            <Change color.Color="#0F0" Duration="1"/>
        </Timeline>
        <Timeline ux:Name="blueFlash">
            <Change color.Color="#00F" Duration="1"/>
        </Timeline>
        <State ux:Binding="Pulling">
            <Cycle Target="redFlash.Progress" Low="0" High="1" Frequency="1" />
        </State>
        <State ux:Binding="PulledPastThreshold">
            <Cycle Target="pinkFlash.Progress" Low="0" High="1" Frequency="1" />
        </State>
        <State ux:Binding="Loading">
            <Cycle Target="greenFlash.Progress" Low="0" High="1" Frequency="1" />
        </State>
        <State ux:Binding="Rest">
            <Cycle Target="blueFlash.Progress" Low="0" High="1" Frequency="1" />
        </State>
    </PullToReload>
    <StackPanel>
        <Text Margin="20">The quick brown fox</Text>
        <Text Margin="20">Jumps over the lazy dog</Text>
    </StackPanel>
    <SolidColor ux:Name="color" Color="#FFF"/>
</ScrollView>

Location

Namespace
Fuse.Triggers
Package
Fuse.Controls.ScrollView 2.9.1
Show Uno properties and methods

Interface of PullToReload

Inherited from ScrollingAnimation

Inherited from Trigger

BackwardAnimation : TriggerAnimation ux

Specifies an explicit backward animation instead of using the implied backward animation of the animators involved. Be aware that actions are not part of the animation.

CrossFadeDuration : double ux

If there is a transition between forward/backward playback and two timeilnes are being used (implicit or explicit) this specifies the cross-fade time.

Deactivate uno

Deactivates the trigger (target progress of 0).

Pulse uno

Plays the trigger to progress 1 then back to 0.

RequireLayout(Visual) uno

Indicates the trigger is bound to the layout of a visual. This will keep the trigger in Bypass mode until after the first layout of the element is obtained. This is required since layout does not happen in the same root grouping/update phase as the creation of the element, yet not having a layout should qualify as part of the rooting period.

Inherited from NodeGroupBase

Nodes : IList of Node ux

Nodes to add to the Parent when this trigger is any non-deactivated state (Progress > 0)

Inherited from 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.

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.

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.

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.

Inherited from PropertyObject

Inherited from object

Attached UX Attributes

GlobalKey (attached by Resource) : string ux

The ux:Global attribute creates a global resource that is accessible everywhere in UX markup.

Implemented Interfaces

IScriptObject uno

Interface for objects that can have a script engine representation