diff options
Diffstat (limited to 'doc/dw-interrupted-drawing.doc')
| -rw-r--r-- | doc/dw-interrupted-drawing.doc | 24 |
1 files changed, 18 insertions, 6 deletions
diff --git a/doc/dw-interrupted-drawing.doc b/doc/dw-interrupted-drawing.doc index b9a7692f..cb84ec8b 100644 --- a/doc/dw-interrupted-drawing.doc +++ b/doc/dw-interrupted-drawing.doc @@ -62,7 +62,7 @@ digraph G { The drawing order of the four elements (represented by widgets) is: - body, -- #sc-1 (background and text), +- #sc-1, - #fl-1, - #sc-2. @@ -73,12 +73,11 @@ Since 3. a widget can only draw its descendants (not neccessary children, but drawing siblings is not allowed), -#sc-2 cannot be drawn as a whole; instead drawing is **interrupted** +#sc-1 cannot be drawn as a whole; instead drawing is **interrupted** by #fl-1. This means: 1. the background and text of #sc-1 is drawn; -2. drawing of #sc-1 is **interrupted** by #fl-1, which means that its - parent, the body, draws #fl-1; +2. drawing of #sc-1 is **interrupted** by #fl-1 (see below for details), 3. drawing of #sc-1 is **continued**, by drawing #sc-2. The exact control flow is described in this sequence diagram: @@ -89,11 +88,24 @@ The exact control flow is described in this sequence diagram: When is drawing interrupted? ============================ -... +A widget holding references to widgets out of flow (which are not +necessary children) draws them as interruption if ... TODO. See +dw::oof::OOFAwareWidget::doesWidgetOOFInterruptDrawing. + How does interruption of drawing work? ====================================== -... +When a widget detects that an other widget should be drawn as +interruption (se above), it calls dw::core::Widget::drawInterruption, +which + +1. draws the widget within another "context" (area and reference + widget); for this the original drawing area + (dw::core::DrawingContext::getToplevelArea) is used. +2. Using dw::core::DrawingContext::addWidgetDrawnAsInterruption, and + checking later with + dw::core::DrawingContext::hasWidgetBeenDrawnAsInterruption prevents + these widgets from being drawn twice. */ |