Docs Help

Terms, Icons, and Labels

Many classes have shortcut names used when creating (instantiating) a class with a configuration object. The shortcut name is referred to as an alias (or xtype if the class extends Ext.Component). The alias/xtype is listed next to the class name of applicable classes for quick reference.

Access Levels

Framework classes or their members may be specified as private or protected. Else, the class / member is public. Public, protected, and private are access descriptors used to convey how and when the class or class member should be used.

Member Types

Member Syntax

Below is an example class member that we can disect to show the syntax of a class member (the lookupComponent method as viewed from the Ext.button.Button class in this case).

lookupComponent ( item ) : Ext.Component
protected

Called when a raw config object is added to this container either during initialization of the items config, or when new items are added), or {@link #insert inserted.

This method converts the passed object into an instanced child component.

This may be overridden in subclasses when special processing needs to be applied to child creation.

Parameters

item :  Object

The config object being added.

Returns
Ext.Component

The component to be added.

Let's look at each part of the member row:

Member Flags

The API documentation uses a number of flags to further commnicate the class member's function and intent. The label may be represented by a text label, an abbreviation, or an icon.

Class Icons

- Indicates a framework class

- A singleton framework class. *See the singleton flag for more information

- A component-type framework class (any class within the Ext JS framework that extends Ext.Component)

- Indicates that the class, member, or guide is new in the currently viewed version

Member Icons

- Indicates a class member of type config

- Indicates a class member of type property

- Indicates a class member of type method

- Indicates a class member of type event

- Indicates a class member of type theme variable

- Indicates a class member of type theme mixin

- Indicates that the class, member, or guide is new in the currently viewed version

Class Member Quick-Nav Menu

Just below the class name on an API doc page is a row of buttons corresponding to the types of members owned by the current class. Each button shows a count of members by type (this count is updated as filters are applied). Clicking the button will navigate you to that member section. Hovering over the member-type button will reveal a popup menu of all members of that type for quick navigation.

Getter and Setter Methods

Getting and setter methods that correlate to a class config option will show up in the methods section as well as in the configs section of both the API doc and the member-type menus just beneath the config they work with. The getter and setter method documentation will be found in the config row for easy reference.

History Bar

Your page history is kept in localstorage and displayed (using the available real estate) just below the top title bar. By default, the only search results shown are the pages matching the product / version you're currently viewing. You can expand what is displayed by clicking on the button on the right-hand side of the history bar and choosing the "All" radio option. This will show all recent pages in the history bar for all products / versions.

Within the history config menu you will also see a listing of your recent page visits. The results are filtered by the "Current Product / Version" and "All" radio options. Clicking on the button will clear the history bar as well as the history kept in local storage.

If "All" is selected in the history config menu the checkbox option for "Show product details in the history bar" will be enabled. When checked, the product/version for each historic page will show alongside the page name in the history bar. Hovering the cursor over the page names in the history bar will also show the product/version as a tooltip.

Search and Filters

Both API docs and guides can be searched for using the search field at the top of the page.

On API doc pages there is also a filter input field that filters the member rows using the filter string. In addition to filtering by string you can filter the class members by access level, inheritance, and read only. This is done using the checkboxes at the top of the page.

The checkbox at the bottom of the API class navigation tree filters the class list to include or exclude private classes.

Clicking on an empty search field will show your last 10 searches for quick navigation.

API Doc Class Metadata

Each API doc page (with the exception of Javascript primitives pages) has a menu view of metadata relating to that class. This metadata view will have one or more of the following:

Expanding and Collapsing Examples and Class Members

Runnable examples (Fiddles) are expanded on a page by default. You can collapse and expand example code blocks individually using the arrow on the top-left of the code block. You can also toggle the collapse state of all examples using the toggle button on the top-right of the page. The toggle-all state will be remembered between page loads.

Class members are collapsed on a page by default. You can expand and collapse members using the arrow icon on the left of the member row or globally using the expand / collapse all toggle button top-right.

Desktop -vs- Mobile View

Viewing the docs on narrower screens or browsers will result in a view optimized for a smaller form factor. The primary differences between the desktop and "mobile" view are:

Viewing the Class Source

The class source can be viewed by clicking on the class name at the top of an API doc page. The source for class members can be viewed by clicking on the "view source" link on the right-hand side of the member row.

Ext JS 6.0.1 - Classic Toolkit


top

Hierarchy

CanvasRenderingContext2D
No members found using the current filters

properties

methods

Instance Methods

arc ( x, y, radius, startAngle, endAngle, anticlockwise )

Adds points to the subpath such that the arc described by the circumference of the circle described by the arguments, starting at the given start angle and ending at the given end angle, going in the given direction (defaulting to clockwise), is added to the path, connected to the previous point by a straight line.

Parameters

x :  Object

y :  Object

radius :  Object

startAngle :  Object

endAngle :  Object

anticlockwise :  Object

arcTo ( x1, y1, x2, y2, radius )

Adds an arc with the given control points and radius to the current subpath, connected to the previous point by a straight line. If two radii are provided, the first controls the width of the arc's ellipse, and the second controls the height. If only one is provided, or if they are the same, the arc is from a circle.

In the case of an ellipse, the rotation argument controls the clockwise inclination of the ellipse relative to the x-axis.

Parameters

x1 :  Object

y1 :  Object

x2 :  Object

y2 :  Object

radius :  Object

bezierCurveTo ( c1x, c1y, c2x, c2y, x, y ) : *

Adds the given point to the current subpath, connected to the previous one by a cubic Bézier curve with the given control points.

Parameters

c1x :  Object

c1y :  Object

c2x :  Object

c2y :  Object

x :  Object

y :  Object

Returns

:*

clearRect ( x, y, w, h )

Clears all pixels on the canvas in the given rectangle to transparent black.

Parameters

x :  Object

y :  Object

w :  Object

h :  Object

createLinearGradient ( x0, y0, x1, y1 ) : *

Returns an object that represents a linear gradient that paints along the line given by the coordinates represented by the arguments.

Parameters

x0 :  Object

y0 :  Object

x1 :  Object

y1 :  Object

Returns

:*

createRadialGradient ( x0, y0, r0, x1, y1, r1 ) : *

Returns a CanvasGradient object that represents a radial gradient that paints along the cone given by the circles represented by the arguments. If either of the radii are negative, throws an IndexSizeError exception.

Parameters

x0 :  Object

y0 :  Object

r0 :  Object

x1 :  Object

y1 :  Object

r1 :  Object

Returns

:*

destroy

Destroys the Canvas element and prepares it for Garbage Collection.

drawImage ( img_elem, arg1, arg2, arg3, arg4, dst_x, dst_y, dw, dh ) : *

Draws the given image onto the canvas. If the first argument isn't an img, canvas, or video element, throws a TypeMismatchError exception. If the image has no image data, throws an InvalidStateError exception. If the one of the source rectangle dimensions is zero, throws an IndexSizeError exception. If the image isn't yet fully decoded, then nothing is drawn.

Parameters

img_elem :  Object

arg1 :  Object

arg2 :  Object

arg3 :  Object

arg4 :  Object

dst_x :  Object

dst_y :  Object

dw :  Object

dh :  Object

Returns

:*

fill

Fills the subpaths of the current default path or the given path with the current fill style.

fillRect ( x, y, w, h )

Paints the given rectangle onto the canvas, using the current fill style.

Parameters

x :  Object

y :  Object

w :  Object

h :  Object

fillText ( text, x, y, maxWidth )

Fills the given text at the given position. If a maximum width is provided, the text will be scaled to fit that width if necessary.

Parameters

text :  Object

x :  Object

y :  Object

maxWidth :  Object

lineTo ( x, y )

Adds the given point to the current subpath, connected to the previous one by a straight line.

Parameters

x :  Object

y :  Object

moveTo ( x, y )

Creates a new subpath with the given point.

Parameters

x :  Object

y :  Object

quadraticCurveTo ( cx, cy, x, y ) : *

Adds the given point to the current subpath, connected to the previous one by a quadratic Bézier curve with the given control point.

Parameters

cx :  Object

cy :  Object

x :  Object

y :  Object

Returns

:*

rect ( x, y, w, h ) : *

Adds a new closed subpath to the path, representing the given rectangle.

Parameters

x :  Object

y :  Object

w :  Object

h :  Object

Returns

:*

renderSprite ( sprite ) : Boolean
private pri

Parameters

sprite :  Object

Returns

:Boolean

restore

Pops the state stack and restores the state.

rotate ( radians ) : *

Rotates the transformation matrix.

Parameters

radians :  Object

Returns

:*

save

Pushes the context state to the state stack.

scale ( sx, sy ) : *

Scales the transformation matrix.

Parameters

sx :  Object

sy :  Object

Returns

:*

setTransform ( x2x, x2y, y2x, y2y, newDx, newDy )

Changes the transformation matrix to the matrix given by the arguments as described below.

Parameters

x2x :  Object

x2y :  Object

y2x :  Object

y2y :  Object

newDx :  Object

newDy :  Object

stroke

Strokes the subpaths of the current default path or the given path with the current stroke style.

strokeRect ( x, y, w, h )

Paints the box that outlines the given rectangle onto the canvas, using the current stroke style.

Parameters

x :  Object

y :  Object

w :  Object

h :  Object

strokeText ( text, x, y, maxWidth )

Strokes the given text at the given position. If a maximum width is provided, the text will be scaled to fit that width if necessary.

Parameters

text :  Object

x :  Object

y :  Object

maxWidth :  Object

transform ( x2x, x2y, y2x, y2y, newDx, newDy )

Changes the transformation matrix to apply the matrix given by the arguments as described below.

Parameters

x2x :  Object

x2y :  Object

y2x :  Object

y2y :  Object

newDx :  Object

newDy :  Object

translate ( dx, dy ) : *

Translates the transformation matrix.

Parameters

dx :  Object

dy :  Object

Returns

:*

updateRect ( rect )

Normally, a surface will have a single canvas. However, on certain platforms/browsers there's a limit to how big a canvas can be. 'splitThreshold' is used to determine maximum width/height of a single canvas element. When a surface is wider/taller than the splitThreshold, extra canvas element(s) will be created and tiled inside the surface.

Parameters

rect :  Object

Ext JS 6.0.1 - Classic Toolkit