CApplication

constructor(canvas: HTMLCanvasElement, paintDevice?: CApplicationPaintDevice);

Creates the application for an HTML canvas element. @param canvas Canvas used for rendering and pointer input. @param paintDevice Optional paint device targeting the same canvas. Defaults to Canvas 2D. @throws Error if another CApplication instance already exists.

resizeCanvas(width: number, height: number, pixelRatio?: number): void;

Resizes the logical viewport and its high resolution bitmap. Only top-level widgets already filling the old viewport follow its size.

destroy(): void;

Destroys the application, removes browser event listeners and clears application-managed state.

static instance(): CApplication;

Returns the current application instance. @returns Current application instance. @throws Error if no CApplication has been created.

static exists(): boolean;

Checks whether an application instance exists. @returns `true` if a CApplication currently exists.

canvas(): HTMLCanvasElement;

Returns the HTML canvas used by the application. @returns Application canvas element.

paintDevice(): CPaintDevice;

Returns the paint device associated with the application canvas. @returns Application paint device.

topLevelWidgets(): readonly CWidget[];

Returns the registered top-level widgets. @returns Snapshot of the top-level widget list.

font(): CFont;

Returns the application default font. @returns Independent copy of the current font.

setFont(font: CFont): void;

Sets the application default font and schedules a repaint. @param font Font to use as the application default.

palette(): CPalette;

Returns the application palette. @returns Current application palette.

setPalette(palette: CPalette): void;

Sets the palette inherited by widgets without local overrides and repaints. Reapplying the same instance also repaints, for example after CCssPalette.reload(). @param palette Palette to use.

style(): CStyle;

Returns the application style. @returns Current application style.

setStyle(style: CStyle): void;

Sets the application style and schedules a repaint. @param style Style to use.

registerTopLevelWidget(widget: CWidget): void;

Registers a top-level widget. @param widget Parentless widget to register. @throws Error if the widget has a parent.

unregisterTopLevelWidget(widget: CWidget): void;

Unregisters a top-level widget. @param widget Widget to unregister.

updatesEnabled(): boolean;

Returns whether repaint updates are enabled. @returns `true` if updates are enabled.

focusWidget(): CWidget | null;

Returns the widget that currently owns keyboard focus. @returns Focus widget, or `null` if none.

setFocusWidget(widget: CWidget | null): void;

Changes the keyboard focus widget and dispatches focus-out/focus-in events. @param widget Widget to focus, or `null` to clear focus.

run(): void;

Enables repaint updates and requests a repaint.

stopUpdates(): void;

Disables repaint updates and cancels any pending animation frame.

requestRepaint(): void;

Schedules a repaint on the next animation frame when updates are enabled.

grabMouse(widget: CWidget): void;

Routes subsequent mouse events to a specific widget. @param widget Widget that should grab mouse input.

releaseMouse(): void;

Releases the current mouse grab.

mouseGrabber(): CWidget | null;

Returns the widget currently grabbing mouse input. @returns Mouse grabber, or `null`.

hoverWidget(): CWidget | null;

Returns the widget currently under the pointer. @returns Hovered widget, or `null`.

closeAllPopups(): void;

Closes all currently registered popup widgets.

popupWidgets(): readonly CPopupWidget[];

Returns the registered popup widgets in stacking order. @returns Snapshot of the popup widget list.

registerPopupWidget(widget: CPopupWidget): void;

Registers a popup widget and moves it to the top of the popup stack. @param widget Popup widget to register.

unregisterPopupWidget(widget: CPopupWidget): void;

Unregisters a popup widget. @param widget Popup widget to unregister.

registerWindowWidget(widget: CWidget): void;

Registers a window widget and moves it to the top of the window stack. @param widget Window widget to register.

unregisterWindowWidget(widget: CWidget): void;

Unregisters a window widget. @param widget Window widget to unregister.

isWindowWidget(widget: CWidget): boolean;

Checks whether a widget is registered as a window. @param widget Widget to test. @returns `true` if the widget is a registered window.

registerModalWidget(widget: CWidget): void;

Registers a modal widget after closing open popups. @param widget Modal widget to register.

rememberNonModalFocus(dialog: CWidget): void;

@internal Records focus before opening a non-modal dialog.

restoreNonModalFocus(dialog: CWidget, hadFocus: boolean): void;

@internal Discards the saved focus and optionally restores it after hiding the dialog.

unregisterModalWidget(widget: CWidget): void;

Unregisters a modal widget. @param widget Modal widget to unregister.

modalWidgets(): readonly CWidget[];

Returns the registered modal widgets. @returns Snapshot of the modal widget stack.

topModalWidget(): CWidget | null;

Returns the topmost modal widget. @returns Top modal widget, or `null` when no modal widget is registered.

toolTipVisible(): boolean;

Returns whether a tooltip is currently visible. @returns `true` if a tooltip is visible.

focusNextWidget(forward?: boolean): boolean;

Moves keyboard focus to the next or previous focusable widget. @param forward `true` to move forward; `false` to move backward. @returns `true` if focus was moved.

rememberFocusBeforeHide(subtree: CWidget): void;

@internal Keeps the current tab position when a focused subtree is about to be hidden.

focusLabelBuddy(label: CWidget, buddy: CWidget): boolean;

@internal Focus transfer shared by label clicks and Alt mnemonics.

setTabOrder(first: CWidget, second: CWidget): void;

@internal Called by CWidget.setTabOrder().

activeDrag(): CDrag | null;

Returns the active drag operation. @returns Active drag, or `null`.

dragTarget(): CWidget | null;

Returns the current drag target widget. @returns Drag target, or `null`.

startDrag(drag: CDrag): void;

Registers an already active drag operation with the application. @param drag Active drag operation to manage.

cancelDrag(): void;

Cancels the active drag operation and notifies the current drag target.

clipboard(): CClipboard;

Returns the application clipboard. @returns Application clipboard instance.