Struct ViewAssistantContext

pub struct ViewAssistantContext {
    pub key: ViewKey,
    pub size: Size,
    pub metrics: Size,
    pub presentation_time: MonotonicInstant,
    pub buffer_count: Option<usize>,
    pub image_id: ImageId,
    pub image_index: u32,
    pub mouse_cursor_position: Option<IntPoint>,
    pub display_info: Option<DisplayInfo>,
    /* private fields */
}

parameter struct passed to setup and update trait methods.

Fields

key: ViewKey

A unique key representing this view.

size: Size

The actual number of pixels in the view.

metrics: Size

A factor representing pixel density. Use to calculate sizes for things like fonts.

presentation_time: MonotonicInstant

For render, the time the rendering will be presented. Currently not implemented correctly.

buffer_count: Option<usize>

When running in frame buffer mode, the number of buffers in the buffer collection

image_id: ImageId

The ID of the Image being rendered in a buffer in preparation for being displayed. Used to keep track of what content needs to be rendered for a particular image in double or triple buffering configurations.

image_index: u32

The index of the buffer in a buffer collection that is being used as the contents of the image specified in image_id.

mouse_cursor_position: Option<IntPoint>

Position of the mouse cursor when running directly on the display coordinator.

display_info: Option<DisplayInfo>

information about the hosting display when running directly on the display coordinator.

Implementations

impl ViewAssistantContext

pub fn new_for_testing() -> Self

Returns an empty ViewAssistantContext to enable testing with mocks

pub fn queue_message(&mut self, message: Message)

Queue up a message for delivery

pub fn request_render(&self)

Request that a render occur for this view at the next appropriate time to render.