Class SnapToGrid

All Implemented Interfaces:
PositionConstants

public class SnapToGrid extends SnapToHelper
A helper used to perform snapping to a grid, which is specified on the graphical viewer via the various properties defined in this class. This helper can be used in conjunction with the DragEditPartsTracker when dragging editparts within a graphical viewer. When snapping a rectangle, the edges of the rectangle will snap along gridlines.

This helper does not keep up with changes made to the graphical viewer's properties. Clients should instantiate a new helper each time one is requested and not hold on to instances of the helper, if the grid properties specified on the viewer are subject to change.

Since:
3.0
See Also:
  • Field Details

    • PROPERTY_GRID_ENABLED

      public static final String PROPERTY_GRID_ENABLED
      A viewer property indicating whether the snap function is enabled. The value must be a Boolean.
      See Also:
    • PROPERTY_GRID_VISIBLE

      public static final String PROPERTY_GRID_VISIBLE
      A viewer property indicating whether the grid should be displayed. The value must be a Boolean.
      See Also:
    • PROPERTY_GRID_SPACING

      public static final String PROPERTY_GRID_SPACING
      A viewer property indicating the grid spacing. The value must be a Dimension.
      See Also:
    • PROPERTY_GRID_ORIGIN

      public static final String PROPERTY_GRID_ORIGIN
      A viewer property indicating the grid's origin. The value must be a Point.
      See Also:
    • DEFAULT_GRID_SIZE

      public static final int DEFAULT_GRID_SIZE
      The default grid size if the viewer does not specify a size.
      See Also:
    • DEFAULT_GAP

      public static final int DEFAULT_GAP
      Deprecated.
      use DEFAULT_GRID_SIZE
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    • container

      protected GraphicalEditPart container
      The graphical part whose content's figure defines the grid.
    • gridX

      protected int gridX
      The horizontal interval for the grid
    • gridY

      protected int gridY
      The vertical interval for the grid
    • origin

      protected Point origin
      The origin of the grid.
  • Constructor Details

    • SnapToGrid

      public SnapToGrid(GraphicalEditPart container)
      Constructs a gridded snap helper on the given editpart. The editpart should be the graphical editpart whose contentspane figure is used as the reference for the grid.
      Parameters:
      container - the editpart which the grid is on
  • Method Details

    • snapRectangle

      public int snapRectangle(Request request, int snapLocations, PrecisionRectangle rect, PrecisionRectangle result)
      Description copied from class: SnapToHelper
      Applies a snap correction to a Rectangle based on a given Rectangle. The provided baseRect will be used as a reference for snapping. The types of snapping to be performed are indicated by the snapOrientation parameter. The correction is applied to the result field.

      The baseRect is not modified. The correction is applied to the result. The request's extended data may contain additional information about the snapping which was performed.

      All coordinate information received and returned by this method should be in absolute coordinates.

      Specified by:
      snapRectangle in class SnapToHelper
      Parameters:
      request - the request or null
      snapLocations - the input snap locations
      rect - the input rectangle
      result - the correction is applied to this rectangle
      Returns:
      the remaining snap locations
      See Also: