MIDP Canvas Repainting
The low-level user-interface APIs canvas painting of the Mobile Information Device Profile (MIDP) allow you to control exactly what is drawn on the screen through the Canvas class. Sometimes, though, you also want to have control over when the drawing occurs, or to be notified when the drawing is complete. Before exploring either topic, nfl jerseys I should recap how canvas painting works in a general sense.
Generally, it is the device that controls when painting occurs. A painting event is triggered when any of a number of things occur — the canvas is shown for the first time, a menu that was hiding part of the swiss watch brand canvas is withdrawn, or an alert is dismissed. The device then invokes the canvas’’s paint method, passing it a Graphics object initialized to draw on the correct parts of the display. The method does the drawing and returns as quickly as possible. Note that no key or pointer events are communion dresses processed while the painting occurs — execution of events, including repaint notifications, is always serialized.
The system queues a paint bridal gowns request for the given area. (Another version of the repaint method takes no arguments and queues a paint request for the entire canvas.) If you mark two or more areas for repainting within a short span of time, the system may combine the paint requests into a single request rs money to paint the union of the two areas (the smallest rectangle containing both). At some point the system invokes the canvas’’s paint method, passing it a Graphics object whose clipping area is set to the area that needs repainting. You can call the repaint method from any thread, because the MIDP user-interface power leveling classes are all thread-safe, unlike the J2SE Swing classes you may already be familiar with.