Struct ElementHandle

#[repr(C)]
pub struct ElementHandle { /* private fields */ }

ElementHandle wraps an existing element in a Slint UI. An ElementHandle does not keep the corresponding element in the UI alive. Use Self::is_valid() to verify that it is still alive.

Obtain instances of ElementHandle by querying your application through Self::find_by_accessible_label().

Implementations

impl ElementHandle

pub fn visit_descendants<R>( &self, visitor: impl FnMut(ElementHandle) -> ControlFlow<R>, ) -> Option<R>

Visit all descendants of this element and call the visitor to each of them, until the visitor returns ControlFlow::Break. When the visitor breaks, the function returns the value. If it doesn’t break, the function returns None.

pub fn query_descendants(&self) -> ElementQuery

Creates a new ElementQuery to match any descendants of this element.

pub fn find_by_accessible_label( component: &impl ElementRoot, label: &str, ) -> impl Iterator<Item = Self>

This function searches through the entire tree of elements of component, looks for elements that have a accessible-label property with the provided value label, and returns an iterator over the found elements.

pub fn find_by_element_id( component: &impl ElementRoot, id: &str, ) -> impl Iterator<Item = Self>

This function searches through the entire tree of elements of this window and looks for elements by their id. The id is a qualified string consisting of the name of the component and the assigned name within the component. In the following examples, the first Button has the id “MyView::submit-button” and the second button “App::close”:

component MyView {
   submit-button := Button {}
}
export component App {
    VerticalLayout {
        close := Button {}
    }
}

pub fn find_by_element_type_name( component: &impl ElementRoot, type_name: &str, ) -> impl Iterator<Item = Self>

This function searches through the entire tree of elements of component, looks for elements with given type name.

pub fn is_valid(&self) -> bool

Returns true if the element still exists in the in UI and is valid to access; false otherwise.

pub fn id(&self) -> Option<SharedString>

Returns the element’s qualified id. Returns None if the element is not valid anymore or the element does not have an id. A qualified id consists of the name of the surrounding component as well as the provided local name, separate by a double colon.

slint::slint!{

component PushButton {
    /* .. */
}

export component App {
   mybutton := PushButton { } // known as `App::mybutton`
   PushButton { } // no id
}

}

let app = App::new().unwrap();
let button = i_slint_backend_testing::ElementHandle::find_by_element_id(&app, "App::mybutton")
             .next().unwrap();
assert_eq!(button.id().unwrap(), "App::mybutton");

pub fn type_name(&self) -> Option<SharedString>

Returns the element’s type name; None if the element is not valid anymore.

slint::slint!{

component PushButton {
    /* .. */
}

export component App {
   mybutton := PushButton { }
}

}

let app = App::new().unwrap();
let button = i_slint_backend_testing::ElementHandle::find_by_element_id(&app, "App::mybutton")
             .next().unwrap();
assert_eq!(button.type_name().unwrap(), "PushButton");

pub fn bases(&self) -> Option<impl Iterator<Item = SharedString>>

Returns the element’s base types as an iterator; None if the element is not valid anymore.

slint::slint!{

component ButtonBase {
    /* .. */
}

component PushButton inherits ButtonBase {
    /* .. */
}

export component App {
   mybutton := PushButton { }
}

}

let app = App::new().unwrap();
let button = i_slint_backend_testing::ElementHandle::find_by_element_id(&app, "App::mybutton")
             .next().unwrap();
assert_eq!(button.type_name().unwrap(), "PushButton");
assert_eq!(button.bases().unwrap().collect::<Vec<_>>(),
          ["ButtonBase"]);

pub fn accessible_role(&self) -> Option<AccessibleRole>

Returns the value of the element’s accessible-role property, if present. Use this property to locate elements by their type/role, i.e. buttons, checkboxes, etc.

pub fn invoke_accessible_default_action(&self)

Invokes the default accessible action on the element. For example a MyButton element might declare an accessible default action that simulates a click, as in the following example:

component MyButton {
    // ...
    callback clicked();
    in property <string> text;

    TouchArea {
        clicked => { root.clicked() }
    }
    accessible-role: button;
    accessible-label: self.text;
    accessible-action-default => { self.clicked(); }
}

pub fn accessible_value(&self) -> Option<SharedString>

Returns the value of the element’s accessible-value property, if present.

pub fn accessible_placeholder_text(&self) -> Option<SharedString>

Returns the value of the element’s accessible-placeholder-text property, if present.

pub fn set_accessible_value(&self, value: impl Into<SharedString>)

Sets the value of the element’s accessible-value property. Note that you can only set this property if it is declared in your Slint code.

pub fn accessible_value_maximum(&self) -> Option<f32>

Returns the value of the element’s accessible-value-maximum property, if present.

pub fn accessible_value_minimum(&self) -> Option<f32>

Returns the value of the element’s accessible-value-minimum property, if present.

pub fn accessible_value_step(&self) -> Option<f32>

Returns the value of the element’s accessible-value-step property, if present.

pub fn accessible_label(&self) -> Option<SharedString>

Returns the value of the accessible-label property, if present.

pub fn accessible_enabled(&self) -> Option<bool>

Returns the value of the accessible-enabled property, if present

pub fn accessible_description(&self) -> Option<SharedString>

Returns the value of the accessible-description property, if present

pub fn accessible_checked(&self) -> Option<bool>

Returns the value of the accessible-checked property, if present

pub fn accessible_checkable(&self) -> Option<bool>

Returns the value of the accessible-checkable property, if present

pub fn accessible_item_selected(&self) -> Option<bool>

Returns the value of the accessible-item-selected property, if present

pub fn accessible_item_selectable(&self) -> Option<bool>

Returns the value of the accessible-item-selectable property, if present

pub fn accessible_item_index(&self) -> Option<usize>

Returns the value of the element’s accessible-item-index property, if present.

pub fn accessible_item_count(&self) -> Option<usize>

Returns the value of the element’s accessible-item-count property, if present.

pub fn size(&self) -> LogicalSize

Returns the size of the element in logical pixels. This corresponds to the value of the width and height properties in Slint code. Returns a zero size if the element is not valid.

pub fn absolute_position(&self) -> LogicalPosition

Returns the position of the element within the entire window. This corresponds to the value of the absolute-position property in Slint code. Returns a zero position if the element is not valid.

pub fn computed_opacity(&self) -> f32

Returns the opacity that is applied when rendering this element. This is the product of the opacity property multipled with any opacity specified by parent elements. Returns zero if the element is not valid.

pub fn invoke_accessible_increment_action(&self)

Invokes the element’s accessible-action-increment callback, if declared. On widgets such as spinboxes, this typically increments the value.

pub fn invoke_accessible_decrement_action(&self)

Invokes the element’s accessible-action-decrement callback, if declared. On widgets such as spinboxes, this typically decrements the value.

pub async fn single_click(&self, button: PointerEventButton)

Simulates a single click (or touch tap) on the element at its center point with the specified button.

pub async fn double_click(&self, button: PointerEventButton)

Simulates a double click (or touch tap) on the element at its center point.

Trait Implementations

impl Clone for ElementHandle

fn clone(&self) -> ElementHandle

Returns a copy of the value.

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

Performs copy-assignment from source.