Trait i_slint_core::renderer::Renderer

pub trait Renderer {
    fn text_size(
        &self,
        font_request: FontRequest,
        text: &str,
        max_width: Option<Coord>,
        scale_factor: f32
    ) -> Size;
    fn text_input_byte_offset_for_position(
        &self,
        text_input: Pin<&TextInput>,
        pos: Point
    ) -> usize;
    fn text_input_cursor_rect_for_byte_offset(
        &self,
        text_input: Pin<&TextInput>,
        byte_offset: usize
    ) -> Rect;

    fn free_graphics_resources(
        &self,
        _items: &mut dyn Iterator<Item = Pin<ItemRef<'_>>>
    ) { ... }
    fn mark_dirty_region(&self, _region: DirtyRegion) { ... }
    fn register_font_from_memory(
        &self,
        _data: &'static [u8]
    ) -> Result<(), Box<dyn Error>> { ... }
    fn register_font_from_path(&self, _path: &Path) -> Result<(), Box<dyn Error>> { ... }
    fn register_bitmap_font(&self, _font_data: &'static BitmapFont) { ... }
    fn set_rendering_notifier(
        &self,
        _callback: Box<dyn RenderingNotifier>
    ) -> Result<(), SetRenderingNotifierError> { ... }
}

Required Methods

fn text_size(
    &self,
    font_request: FontRequest,
    text: &str,
    max_width: Option<Coord>,
    scale_factor: f32
) -> Size

Returns the size of the given text in logical pixels. When set, max_width means that one need to wrap the text so it does not go further than that

fn text_input_byte_offset_for_position(
    &self,
    text_input: Pin<&TextInput>,
    pos: Point
) -> usize

Returns the (UTF-8) byte offset in the text property that refers to the character that contributed to the glyph cluster that’s visually nearest to the given coordinate. This is used for hit-testing, for example when receiving a mouse click into a text field. Then this function returns the “cursor” position.

fn text_input_cursor_rect_for_byte_offset(
    &self,
    text_input: Pin<&TextInput>,
    byte_offset: usize
) -> Rect

That’s the opposite of Self::text_input_byte_offset_for_position It takes a (UTF-8) byte offset in the text property, and returns a Rectangle left to the char. It is one logical pixel wide and ends at the baseline.

Provided Methods

fn free_graphics_resources(
    &self,
    _items: &mut dyn Iterator<Item = Pin<ItemRef<'_>>>
)

Clear the caches for the items that are being removed

fn mark_dirty_region(&self, _region: DirtyRegion)

Mark a given region as dirty regardless whether the items actually are dirty.

Example: when a PopupWindow disapear, the region under the popup needs to be redrawn

fn register_font_from_memory(
    &self,
    _data: &'static [u8]
) -> Result<(), Box<dyn Error>>

This function can be used to register a custom TrueType font with Slint, for use with the font-family property. The provided slice must be a valid TrueType font.

fn register_font_from_path(&self, _path: &Path) -> Result<(), Box<dyn Error>>

This function can be used to register a custom TrueType font with Slint, for use with the font-family property. The provided path must refer to a valid TrueType font.

fn register_bitmap_font(&self, _font_data: &'static BitmapFont)

fn set_rendering_notifier(
    &self,
    _callback: Box<dyn RenderingNotifier>
) -> Result<(), SetRenderingNotifierError>

This function is called through the public API to register a callback that the backend needs to invoke during different phases of rendering.

Implementors