Struct ExternCanvas

pub struct ExternCanvas {
    pub handle: ControlHandle,
}

An ExternCanvas is a window/children control that is painted to by an external API (such as OpenGL, Vulkan or DirectX).

When building a ExternCanvas, leaving the parent field empty will create a window-like canvas. If a parent is set, the canvas will be a children control (like a button). When used as a child, ExternCanvas can be used as a way to add highly dynamic controls to a NWG application (ex: a video player).

Requires the extern-canvas feature.

As a top level window, the extern canvas has the same features as the window control. As a children control, resize and move events cannot be triggered and window parameters are not visible.

Builder parameters:

• flags: The window flags. See ExternCanvasFlags
• ex_flags: A combination of win32 window extended flags. Unlike flags, ex_flags must be used straight from winapi
• title: The text in the window title bar
• size: The default size of the window
• position: The default position of the window in the desktop
• icon: The window icon
• parent: Logical parent of the window, unlike children controls, this is NOT required.

Control events:

• OnInit: The window was created
• MousePress(_): Generic mouse press events on the button
• OnMouseMove: Generic mouse mouse event
• OnMouseWheel: Generic mouse wheel event
• OnPaint: Generic on paint event
• OnKeyPress: Generic key press
• OnKeyRelease: Generic ket release
• OnResize: When the window is resized
• OnResizeBegin: Just before the window begins being resized by the user
• OnResizeEnd: Just after the user stops resizing the window
• OnWindowMaximize: When the window is maximized
• OnWindowMinimize: When the window is minimized
• OnMove: When the window is moved by the user
• OnMinMaxInfo: When the size or position of the window is about to change and the size of the windows must be restricted

Fields

handle: ControlHandle

Implementations

impl ExternCanvas

pub fn builder<'a>() -> ExternCanvasBuilder<'a>

pub fn invalidate(&self)

Invalidate the whole drawing region. For canvas that are children control, this should be called in the paint event.

pub fn icon(&self) -> Option<Icon>

Return the icon of the window

pub fn set_icon(&self, icon: Option<&Icon>)

Set the icon in the window

• icon: The new icon. If None, the icon is removed

pub fn focus(&self) -> bool

Return true if the control currently has the keyboard focus

pub fn set_focus(&self)

Set the keyboard focus on the button

pub fn enabled(&self) -> bool

Return true if the control user can interact with the control, return false otherwise

pub fn set_enabled(&self, v: bool)

Enable or disable the control

pub fn visible(&self) -> bool

Return true if the control is visible to the user. Will return true even if the control is outside of the parent client view (ex: at the position (10000, 10000))

pub fn set_visible(&self, v: bool)

Show or hide the control to the user

pub fn size(&self) -> (u32, u32)

Return the size of the button in the parent window

pub fn physical_size(&self) -> (u32, u32)

Return the physical size of canvas in pixels considering the dpi scale

pub fn set_size(&self, x: u32, y: u32)

Set the size of the button in the parent window

pub fn position(&self) -> (i32, i32)

Return the position of the button in the parent window

pub fn set_position(&self, x: i32, y: i32)

Set the position of the button in the parent window

pub fn text(&self) -> String

Return window title

pub fn set_text<'a>(&self, v: &'a str)

Set the window title

pub fn class_name(&self) -> &'static str

Winapi class name used during control creation

pub fn flags(&self) -> u32

pub fn forced_flags(&self) -> u32

Winapi flags required by the control

Trait Implementations

impl Default for ExternCanvas

fn default() -> ExternCanvas

Returns the “default value” for a type.

impl Drop for ExternCanvas

fn drop(&mut self)

Executes the destructor for this type.

impl From<&ExternCanvas> for ControlHandle

fn from(control: &ExternCanvas) -> Self

Converts to this type from the input type.

impl From<&mut ExternCanvas> for ControlHandle

fn from(control: &mut ExternCanvas) -> Self

Converts to this type from the input type.

impl PartialEq<ControlHandle> for ExternCanvas

fn eq(&self, other: &ControlHandle) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialEq<ExternCanvas> for ControlHandle

fn eq(&self, other: &ExternCanvas) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.