Abstract parent for any class that wants to be notified when the canvas is about to start drawing. More...
#include <PlotCanvas.h>
Public Member Functions | |
| PlotDrawWatcher () | |
| Constructor. | |
| virtual | ~PlotDrawWatcher () |
| Destructor. | |
| virtual bool | canvasDrawBeginning (PlotOperationPtr drawOperation, bool drawingIsThreaded, int drawnLayersFlag)=0 |
| This method should be called by the canvas whenever drawing is about to begin. | |
Abstract parent for any class that wants to be notified when the canvas is about to start drawing.
This class is needed because a canvas could start redrawing for a number of reasons (user-requested, items changing the scale, resizing, ...) and instead of forcing applications to catch all cases this class can be used to notify when a drawing has begun for any reason.
Definition at line 53 of file PlotCanvas.h.
| casa::PlotDrawWatcher::PlotDrawWatcher | ( | ) | [inline] |
Constructor.
Definition at line 56 of file PlotCanvas.h.
| virtual casa::PlotDrawWatcher::~PlotDrawWatcher | ( | ) | [inline, virtual] |
Destructor.
Definition at line 59 of file PlotCanvas.h.
| virtual bool casa::PlotDrawWatcher::canvasDrawBeginning | ( | PlotOperationPtr | drawOperation, | |
| bool | drawingIsThreaded, | |||
| int | drawnLayersFlag | |||
| ) | [pure virtual] |
This method should be called by the canvas whenever drawing is about to begin.
The watcher is given: A pointer to the PlotOperation object which is updated with progress information, A flag indicating whether the drawing will happen in its own thread or not, A flag indicating which layers are going to be drawn (bitwise-or of PlotCanvasLayer values). The method should return true UNLESS the watcher wants to stop the canvas from drawing. For example, if a canvas does not have threaded drawing, the watcher may want to stop drawing initially in order to spawn a new thread and then redraw.
Implemented in casa::PlotMSPlotter.
1.6.1
