Interface IPainter

All Known Implementing Classes:
AnnotationPainter, CursorLinePainter, MarginPainter, MatchingCharacterPainter, WhitespaceCharacterPainter

public interface IPainter
A painter is responsible for creating, managing, updating, and removing visual decorations on an ITextViewer's text widget. Examples are the highlighting of the caret line, the print margin, or the highlighting of matching peer characters such as pairs of brackets.

Clients may implement this interface.

Painters should be registered with a PaintManager. The paint manager tracks several classes of events issued by an ITextViewer and reacts by appropriately invoking the registered painters.

Painters are either active or inactive. Usually, painters are initially inactive and are activated by the first call to their paint method. Painters can be deactivated by calling deactivate. Inactive painter can be reactivated by calling paint.

Painters usually have to manage state information. E.g., a painter painting a caret line highlight must redraw the previous and the actual caret line in the advent of a change of the caret position. This state information must be adapted to changes of the viewer's content. In order to support this common scenario, the PaintManager gives a painter access to a IPaintPositionManager. The painter can use this updater to manage its state information.

Since:
2.1
See Also:
  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    static final int
    Constant describing the reason of a repaint request: paint manager or painter configuration changed.
    static final int
    Constant describing the reason of a repaint request: paint manager internal change.
    static final int
    Constant describing the reason of a repaint request: key pressed.
    static final int
    Constant describing the reason of a repaint request: mouse button pressed.
    static final int
    Constant describing the reason of a repaint request: selection changed.
    static final int
    Constant describing the reason of a repaint request: text changed.
  • Method Summary

    Modifier and Type
    Method
    Description
    void
    deactivate(boolean redraw)
    Deactivates this painter.
    void
    Disposes this painter.
    void
    paint(int reason)
    Requests this painter to repaint because of the given reason.
    void
    Sets the paint position manager that can be used by this painter or removes any previously set paint position manager.
  • Field Details

    • SELECTION

      static final int SELECTION
      Constant describing the reason of a repaint request: selection changed.
      See Also:
    • TEXT_CHANGE

      static final int TEXT_CHANGE
      Constant describing the reason of a repaint request: text changed.
      See Also:
    • KEY_STROKE

      static final int KEY_STROKE
      Constant describing the reason of a repaint request: key pressed.
      See Also:
    • MOUSE_BUTTON

      static final int MOUSE_BUTTON
      Constant describing the reason of a repaint request: mouse button pressed.
      See Also:
    • INTERNAL

      static final int INTERNAL
      Constant describing the reason of a repaint request: paint manager internal change.
      See Also:
    • CONFIGURATION

      static final int CONFIGURATION
      Constant describing the reason of a repaint request: paint manager or painter configuration changed.
      See Also:
  • Method Details

    • dispose

      void dispose()
      Disposes this painter. Prior to disposing, a painter should be deactivated. A disposed painter can not be reactivated.
      See Also:
    • paint

      void paint(int reason)
      Requests this painter to repaint because of the given reason. Based on the given reason the painter can decide whether it will repaint or not. If it repaints and is inactive, it will activate itself.
      Parameters:
      reason - the repaint reason, value is one of the constants defined in this interface
    • deactivate

      void deactivate(boolean redraw)
      Deactivates this painter. If the painter is inactive, this call does not have any effect. redraw indicates whether the painter should remove any decoration it previously applied. A deactivated painter can be reactivated by calling paint.
      Parameters:
      redraw - true if any previously applied decoration should be removed
      See Also:
    • setPositionManager

      void setPositionManager(IPaintPositionManager manager)
      Sets the paint position manager that can be used by this painter or removes any previously set paint position manager.
      Parameters:
      manager - the paint position manager or null