Ceefax Architecture Overview

1
Ceefax Architecture Overview

• Phase 1

2
The Grid

• Grid builder used to construct the grid
• Grid consists of grid items
• x,y, height etc (not used by Ceefax yet)

3
The Layout

• Layout Manager used to manage the layout items
• Flow arguments, story count and format styles can
  be set

4
CeefaxRenderProvider

• Passed an OutputJob for an OutputJob typeStory,
  Index, Puffbox
• Creates CeefaxPage. populate(cfx_page) method
  pushes the template down the line
• x CeefaxPage.render() x0.toBytes will
  return the payload for transport processor or for
  preview Previewer.toHTML(x0).

5
Layout Rendering

• CeefaxRenderprovider class gets a Layout,
  CeefaxPage and CeefaxSinglePageTemplate and calls
  the LayoutRenderer.populate(page)
• LayoutBlockRenderer
• Loop layoutContent
• if (row)
• new CeefaxTable(x,y)
• loop
• content.populate(page)
• if (column)
• loop
• content.populate(page)..

6
CeefaxStoryList
7
Format Components Styles

• FormatComponents implement the populate(page).
  HeadlineFormatComponent knows how to get a
  headline from the RenderContext and populates the
  parent CeefaxTempate with a TextCell with
  attributes depending on the FormatStyle.
• Format Components have inherited styles plus
  properties associated with the component.
• Story lists built up from multiple calls to
  CeefaxFormatStory

8
Class Dependencies
9
Populating a CeefaxTemplate

• populate (CeefaxWindowTemplate aCeefaxWindowTempla
  te)
• if (row)
• new CeefaxTable(x,y)
• new CeefaxTableRow
• loop layoutContentItemsArray
• new CeefaxTableData(x,y) // x,y Taken from
  grid
• layoutContentItem.populate(CeefaxTableData)
• CeefaxTableRow.addTableData(CeefaxTableData)
• end loop
• aCeefaxWindowTemplate.addChild(CeefaxTable)
• end if
• else if (column)
• loop layoutContentItemsArray
• layoutContentItem.populate(aCeefaxWindowTempla
  te)
• end if