CanvasRenderingContext2D.asyncDrawXULElement()

The non-standard and internal only CanvasRenderingContext2D.asyncDrawXULElement() method of the Canvas 2D API renders a region of a XUL element into the canvas.

This API cannot be used by Web content. It is chrome only.

Syntax

void ctx.asyncDrawXULElement(element, x, y, w, h, bgColor, flags = 0);

Parameters

window

The XULElement to render.

x

The X coordinate of the element.

y

The Y coordnate of the element.

w

The width of the element.

h

The height of the element.

bgColor

A DOMString that specifies the color the canvas is filled with before the element is rendered into it. This color may be transparent/translucent. It is given as a CSS color string (for example, rgb() or rgba()).

flags Optional

Used to better control the asyncDrawXULElement call. Flags can be ORed together.

Constant	Value	Description
DRAWWINDOW_DRAW_CARET	0x01	Show the caret if appropriate when drawing.
DRAWWINDOW_DO_NOT_FLUSH	0x02	Do not flush pending layout notifications that could otherwise be batched up.
DRAWWINDOW_DRAW_VIEW	0x04	Draw scrollbars and scroll the viewport if they are present.
DRAWWINDOW_USE_WIDGET_LAYERS	0x08	Use the widget layer manager if available. This means hardware acceleration may be used, but it might actually be slower or lower quality than normal. It will, however, more accurately reflect the pixels rendered to the screen.
DRAWWINDOW_ASYNC_DECODE_IMAGES	0x10	Do not synchronously decode images - draw what we have.

Specifications

Not part of any current specification or draft. This is a non-standard and internal only API.

Browser compatibility

See also

• The interface defining it, CanvasRenderingContext2D.