--- title: "slint::Window Class" --- ```cpp class Window; ``` ```cpp #include ``` This class represents a window towards the windowing system, that's used to render the scene of a component. It provides API to control windowing system specific aspects such as the position on the screen. ## Public Functions ### `Window` ```cpp slint::Window::Window(const Window &other)=delete ``` ### `operator=` ```cpp Window & slint::Window::operator=(const Window &other)=delete ``` ### `Window` ```cpp slint::Window::Window(Window &&other)=delete ``` ### `operator=` ```cpp Window & slint::Window::operator=(Window &&other)=delete ``` ### `~Window` ```cpp slint::Window::~Window()=default ``` Destroys this window. [Window](./) instances are explicitly shared and reference counted. If this window instance is the last one referencing the window towards the windowing system, then it will also become hidden and destroyed. ### `show` ```cpp void slint::Window::show() ``` Shows the window on the screen. An additional strong reference on the associated component is maintained while the window is visible. Call [hide()](./#hide) to make the window invisible again, and drop the additional strong reference. ### `hide` ```cpp void slint::Window::hide() ``` Hides the window, so that it is not visible anymore. The additional strong reference on the associated component, that was created when [show()](./#show) was called, is dropped. ### `is_visible` ```cpp bool slint::Window::is_visible() const ``` Returns the visibility state of the window. This function can return false even if you previously called [show()](./#show) on it, for example if the user minimized the window. ### `set_rendering_notifier` ```cpp std::optional slint::Window::set_rendering_notifier(F &&callback) const ``` This function allows registering a callback that's invoked during the different phases of rendering. This allows custom rendering on top or below of the scene. The provided callback must be callable with a [slint::RenderingState](../renderingstate/) and the [slint::GraphicsAPI](../graphicsapi/) argument. On success, the function returns a [std::optional](https://en.cppreference.com/w/cpp/utility/optional) without value. On error, the function returns the error code as value in the [std::optional](https://en.cppreference.com/w/cpp/utility/optional). ### `on_close_requested` ```cpp void slint::Window::on_close_requested(F &&callback) const ``` This function allows registering a callback that's invoked when the user tries to close a window. The callback has to return a CloseRequestResponse. ### `request_redraw` ```cpp void slint::Window::request_redraw() const ``` This function issues a request to the windowing system to redraw the contents of the window. ### `position` ```cpp slint::PhysicalPosition slint::Window::position() const ``` Returns the position of the window on the screen, in physical screen coordinates and including a window frame (if present). ### `set_position` ```cpp void slint::Window::set_position(const slint::LogicalPosition &pos) ``` Sets the position of the window on the screen, in physical screen coordinates and including a window frame (if present). Note that on some windowing systems, such as Wayland, this functionality is not available. ### `set_position` ```cpp void slint::Window::set_position(const slint::PhysicalPosition &pos) ``` Sets the position of the window on the screen, in physical screen coordinates and including a window frame (if present). Note that on some windowing systems, such as Wayland, this functionality is not available. ### `size` ```cpp slint::PhysicalSize slint::Window::size() const ``` Returns the size of the window on the screen, in physical screen coordinates and excluding a window frame (if present). ### `set_size` ```cpp void slint::Window::set_size(const slint::LogicalSize &size) ``` Resizes the window to the specified size on the screen, in logical pixels and excluding a window frame (if present). ### `set_size` ```cpp void slint::Window::set_size(const slint::PhysicalSize &size) ``` Resizes the window to the specified size on the screen, in physical pixels and excluding a window frame (if present). ### `scale_factor` ```cpp float slint::Window::scale_factor() const ``` This function returns the scale factor that allows converting between logical and physical pixels. ### `is_fullscreen` ```cpp bool slint::Window::is_fullscreen() const ``` Returns if the window is currently fullscreen. ### `set_fullscreen` ```cpp void slint::Window::set_fullscreen(bool fullscreen) ``` Set or unset the window to display fullscreen. ### `is_maximized` ```cpp bool slint::Window::is_maximized() const ``` Returns if the window is currently maximized. ### `set_maximized` ```cpp void slint::Window::set_maximized(bool maximized) ``` Maximize or unmaximize the window. ### `is_minimized` ```cpp bool slint::Window::is_minimized() const ``` Returns if the window is currently minimized. ### `set_minimized` ```cpp void slint::Window::set_minimized(bool minimized) ``` Minimize or unminimize the window. ### `dispatch_key_press_event` ```cpp void slint::Window::dispatch_key_press_event(const SharedString &text) ``` Dispatch a key press event to the scene. Use this when you're implementing your own backend and want to forward user input events. The *text* is the unicode representation of the key. ### `dispatch_key_press_repeat_event` ```cpp void slint::Window::dispatch_key_press_repeat_event(const SharedString &text) ``` Dispatch an auto-repeated key press event to the scene. Use this when you're implementing your own backend and want to forward user input events. The *text* is the unicode representation of the key. ### `dispatch_key_release_event` ```cpp void slint::Window::dispatch_key_release_event(const SharedString &text) ``` Dispatch a key release event to the scene. Use this when you're implementing your own backend and want to forward user input events. The *text* is the unicode representation of the key. ### `dispatch_pointer_press_event` ```cpp void slint::Window::dispatch_pointer_press_event(LogicalPosition pos, PointerEventButton button) ``` Dispatches a pointer or mouse press event to the scene. Use this function when you're implementing your own backend and want to forward user pointer/mouse events. *pos* represents the logical position of the pointer relative to the window. *button* is the button that was pressed. ### `dispatch_pointer_release_event` ```cpp void slint::Window::dispatch_pointer_release_event(LogicalPosition pos, PointerEventButton button) ``` Dispatches a pointer or mouse release event to the scene. Use this function when you're implementing your own backend and want to forward user pointer/mouse events. *pos* represents the logical position of the pointer relative to the window. *button* is the button that was released. ### `dispatch_pointer_exit_event` ```cpp void slint::Window::dispatch_pointer_exit_event() ``` Dispatches a pointer exit event to the scene. Use this function when you're implementing your own backend and want to forward user pointer/mouse events. This event is triggered when the pointer exits the window. ### `dispatch_pointer_move_event` ```cpp void slint::Window::dispatch_pointer_move_event(LogicalPosition pos) ``` Dispatches a pointer move event to the scene. Use this function when you're implementing your own backend and want to forward user pointer/mouse events. *pos* represents the logical position of the pointer relative to the window. ### `dispatch_pointer_scroll_event` ```cpp void slint::Window::dispatch_pointer_scroll_event(LogicalPosition pos, float delta_x, float delta_y, slint::cbindgen_private::types::TouchPhase scroll_phase=slint::cbindgen_private::types::TouchPhase::Moved) ``` Dispatches a scroll (or wheel) event to the scene. Use this function when you're implementing your own backend and want to forward user wheel events. *parameter* represents the logical position of the pointer relative to the window. *delta\_x* and *delta\_y* represent the scroll delta values in the X and Y directions in logical pixels. *scroll\_phase* represents the current phase of scrolling. If no phase is available like for mouse scroll wheels, use the default ### `dispatch_resize_event` ```cpp void slint::Window::dispatch_resize_event(slint::LogicalSize s) ``` Set the logical size of this window after a resize event The backend must send this event to ensure that the `width` and `height` property of the root [Window](./) element are properly set. ### `dispatch_scale_factor_change_event` ```cpp void slint::Window::dispatch_scale_factor_change_event(float factor) ``` The window's scale factor has changed. This can happen for example when the display's resolution changes, the user selects a new scale factor in the system settings, or the window is moved to a different screen. Platform implementations should dispatch this event also right after the initial window creation, to set the initial scale factor the windowing system provided for the window. ### `dispatch_window_active_changed_event` ```cpp void slint::Window::dispatch_window_active_changed_event(bool active) ``` The [Window](./) was activated or de-activated. The backend should dispatch this event with true when the window gains focus and false when the window loses focus. ### `dispatch_close_requested_event` ```cpp void slint::Window::dispatch_close_requested_event() ``` The user requested to close the window. The backend should send this event when the user tries to close the window,for example by pressing the close button. This will have the effect of invoking the callback set in [Window::on\_close\_requested()](./#on_close_requested) and then hiding the window depending on the return value of the callback. ### `has_active_animations` ```cpp bool slint::Window::has_active_animations() const ``` Returns true if there is an animation currently active on any property in the [Window](./). ### `take_snapshot` ```cpp std::optional> slint::Window::take_snapshot() const ``` Takes a snapshot of the window contents and returns it as RGBA8 encoded pixel buffer. Note that this function may be slow to call as it may need to re-render the scene. This function is not available in freestanding environments. ### `wayland_surface` ```cpp wl_surface * slint::Window::wayland_surface() const ``` Returns the wl\_surface for this window. If the underlying window handle hasn't been created yet or isn't applicable for the platform, this will return nullptr. ### `wayland_display` ```cpp wl_display * slint::Window::wayland_display() const ``` Returns the wl\_display for this window. If the underlying window handle hasn't been created yet or isn't applicable for the platform, this will return nullptr. ### `appkit_view` ```cpp NSView * slint::Window::appkit_view() const ``` Returns the NSView for this window. If the underlying window handle hasn't been created yet or isn't applicable for the platform, this will return nullptr. ### `win32_hwnd` ```cpp HWND slint::Window::win32_hwnd() const ``` Returns the HINSTANCE for this window. If the underlying window handle hasn't been created yet or isn't applicable for the platform, this will return nullptr. ### `win32_hinstance` ```cpp HINSTANCE slint::Window::win32_hinstance() const ``` Returns the HINSTANCE for this window. If the underlying window handle hasn't been created yet or isn't applicable for the platform, this will return nullptr.