Enum masonry::LifeCycle

#[non_exhaustive]
pub enum LifeCycle {
    WidgetAdded,
    AnimFrame(u64),
    DisabledChanged(bool),
    BuildFocusChain,
    RequestPanToChild(Rect),
    Internal(InternalLifeCycle),
}

Application life cycle events.

Unlike [Event]s, LifeCycle events are generated by Masonry, and may occur at different times during a given pass of the event loop. The LifeCycle::WidgetAdded event, for instance, may occur when the app first launches (during the handling of [Event::WindowConnected]) or it may occur during an on_event pass, if some widget has been added then.

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

WidgetAdded

Sent to a Widget when it is added to the widget tree. This should be the first message that each widget receives.

Widgets should handle this event in order to do any initial setup.

In addition to setup, this event is also used by the framework to track certain types of important widget state.

Registering children

Container widgets (widgets which use WidgetPod to manage children) must ensure that this event is forwarded to those children. The WidgetPod itself will handle registering those children with the system; this is required for things like correct routing of events.

AnimFrame(u64)

Called at the beginning of a new animation frame.

On the first frame when transitioning from idle to animating, interval will be 0. (This logic is presently per-window but might change to per-widget to make it more consistent). Otherwise it is in nanoseconds.

The paint method will be called shortly after this event is finished. As a result, you should try to avoid doing anything computationally intensive in response to an AnimFrame event: it might make the app miss the monitor’s refresh, causing lag or jerky animations.

DisabledChanged(bool)

Called when the Disabled state of the widgets is changed.

To check if a widget is disabled, see is_disabled.

To change a widget’s disabled state, see set_disabled.

BuildFocusChain

Called when the widget tree changes and Masonry wants to rebuild the Focus-chain.

It is the only place from which register_for_focus should be called. By doing so the widget can get focused by other widgets using focus_next or focus_prev.

RequestPanToChild(Rect)

Called when a child widgets uses EventCtx::request_pan_to_this.

Internal(InternalLifeCycle)

Internal Masonry lifecycle event.

This should always be passed down to descendant WidgetPods.

Implementations

impl LifeCycle

pub fn should_propagate_to_hidden(&self) -> bool

Whether this event should be sent to widgets which are currently not visible and not accessible.

If a widget changes which children are hidden it must call children_changed. For a more detailed explanation of the hidden state, see Event::should_propagate_to_hidden.

pub fn short_name(&self) -> &str

Short name, for debug logging.

Essentially returns the enum variant name.

Trait Implementations

impl Clone for LifeCycle

fn clone(&self) -> LifeCycle

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for LifeCycle

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.