Class: Renderer

Blockly.blockRendering.Renderer

class   package   static

The base class for a block renderer.

Constructor

Renderer

new Renderer(name)

Parameter
name	The renderer name.

Implements

Blockly.IRegistrable

Properties

constants_

non-null Blockly.blockRendering.ConstantProvider

constants_

non-null Blockly.blockRendering.ConstantProvider

name

package

string

The renderer name.

overrides

package

nullable Object

Rendering constant overrides, passed in through options.

Methods

createDom

package

createDom(svg, theme)

Create any DOM elements that this renderer needs.

Parameter
svg	SVGElement The root of the workspace's SVG. Value must not be null.
theme	Blockly.Theme The workspace theme object. Value must not be null.

dispose

package

dispose()

Dispose of this renderer. Delete all DOM elements that this renderer and its constants created.

getClassName

package

getClassName() returns string

Gets the class name that identifies this renderer.

Returns

string The CSS class name.

getConnectionPreviewMethod

package

getConnectionPreviewMethod(closest, local, topBlock) returns Blockly.InsertionMarkerManager.PREVIEW_TYPE

Chooses a connection preview method based on the available connection, the current dragged connection, and the block being dragged.

Parameter
closest	Blockly.RenderedConnection The available connection. Value must not be null.
local	Blockly.RenderedConnection The connection currently being dragged. Value must not be null.
topBlock	Blockly.BlockSvg The block currently being dragged. Value must not be null.

Returns

non-null Blockly.InsertionMarkerManager.PREVIEW_TYPE The preview type to display.

getConstants

package

getConstants() returns Blockly.blockRendering.ConstantProvider

Get the current renderer's constant provider. We assume that when this is called, the renderer has already been initialized.

Returns

non-null Blockly.blockRendering.ConstantProvider The constant provider.

init

package

init(theme, opt_rendererOverrides)

Initialize the renderer.

Parameter
theme	Blockly.Theme The workspace theme object. Value must not be null.
opt_rendererOverrides	Optional Object Rendering constant overrides.

makeConstants_

protected

makeConstants_() returns Blockly.blockRendering.ConstantProvider

Create a new instance of the renderer's constant provider.

Returns

non-null Blockly.blockRendering.ConstantProvider The constant provider.

makeDebugger_

protected

makeDebugger_() returns Blockly.blockRendering.Debug

Create a new instance of the renderer's debugger.

Returns

non-null Blockly.blockRendering.Debug The renderer debugger.

makeDrawer_

protected

makeDrawer_(block, info) returns Blockly.blockRendering.Drawer

Create a new instance of the renderer's drawer.

Parameter
block	Blockly.BlockSvg The block to render. Value must not be null.
info	Blockly.blockRendering.RenderInfo An object containing all information needed to render this block. Value must not be null.

Returns

non-null Blockly.blockRendering.Drawer The drawer.

makeMarkerDrawer

package

makeMarkerDrawer(workspace, marker) returns Blockly.blockRendering.MarkerSvg

Create a new instance of the renderer's marker drawer.

Parameter
workspace	Blockly.WorkspaceSvg The workspace the marker belongs to. Value must not be null.
marker	Blockly.Marker The marker. Value must not be null.

Returns

non-null Blockly.blockRendering.MarkerSvg The object in charge of drawing the marker.

makePathObject

package

makePathObject(root, style) returns Blockly.blockRendering.IPathObject

Create a new instance of a renderer path object.

Parameter
root	SVGElement The root SVG element. Value must not be null.
style	Blockly.Theme.BlockStyle The style object to use for colouring. Value must not be null.

Returns

non-null Blockly.blockRendering.IPathObject The renderer path object.

makeRenderInfo_

protected

makeRenderInfo_(block) returns Blockly.blockRendering.RenderInfo

Create a new instance of the renderer's render info object.

Parameter
block	Blockly.BlockSvg The block to measure. Value must not be null.

Returns

non-null Blockly.blockRendering.RenderInfo The render info object.

orphanCanConnectAtEnd

package

orphanCanConnectAtEnd(topBlock, orphanBlock, localType) returns boolean

Checks if an orphaned block can connect to the "end" of the topBlock's block-clump. If the clump is a row the end is the last input. If the clump is a stack, the end is the last next connection. If the clump is neither, then this returns false.

Parameter
topBlock	Blockly.BlockSvg The top block of the block clump we want to try and connect to. Value must not be null.
orphanBlock	Blockly.BlockSvg The orphan block that wants to find a home. Value must not be null.
localType	number The type of the connection being dragged.

Returns

boolean Whether there is a home for the orphan or not.

refreshDom

package

refreshDom(svg, theme)

Refresh the renderer after a theme change.

Parameter
svg	SVGElement The root of the workspace's SVG. Value must not be null.
theme	Blockly.Theme The workspace theme object. Value must not be null.

render

package

render(block)

Render the block.

Parameter
block	Blockly.BlockSvg The block to render. Value must not be null.

shouldHighlightConnection

package

shouldHighlightConnection(_conn) returns boolean

Determine whether or not to highlight a connection.

Parameter
_conn	Blockly.Connection The connection to determine whether or not to highlight.

Returns

boolean True if we should highlight the connection.