Package org.eclipse.gef.layout

Class LayoutContext

java.lang.Object
org.eclipse.gef.layout.LayoutContext
public class LayoutContext extends Object
The LayoutContext provides the context in which to layout a Graph. It maintains an ILayoutAlgorithm that can be applied, supports the handling and execution of pre and post Runnables, and filtering of layout objects using ILayoutFilter.

  • Property Details

  • Field Details

    • LAYOUT_ALGORITHM_PROPERTY

      public static final String LAYOUT_ALGORITHM_PROPERTY
      An LayoutContext notifies registered listeners about changes to the layout algorithm using this property name.
      See Also:

  • Constructor Details

    • LayoutContext

      public LayoutContext()

  • Method Details

    • addLayoutFilter

      public void addLayoutFilter(ILayoutFilter layoutFilter)
      Adds the given ILayoutFilter to this LayoutContext.
      Parameters:
      layoutFilter - The ILayoutFilter to add to this context.

    • applyLayout

      public void applyLayout(boolean clear)
      Applies the layout algorithm of this LayoutContext. The clean flag is passed-in to the layout algorithm to indicate whether the context changed significantly since the last layout pass.
      Parameters:
      clear - true to indicate that the algorithm has to fully re-compute the layout, otherwise false.

    • postLayout

      public void postLayout()
      Initiated by the context or by an ILayoutAlgorithm to perform steps that are scheduled to be run after the layout pass. Should not be called by clients.

    • preLayout

      public void preLayout()
      Initiated by the context or by an ILayoutAlgorithm to perform steps that are scheduled to be run before the layout pass. Should not be called by clients.

    • getGraph

      public org.eclipse.gef.graph.Graph getGraph()
      Returns the graph that is to be layouted.
      Returns:
      The Graph that is to be layouted.

    • setGraph

      public void setGraph(org.eclipse.gef.graph.Graph graph)
      Sets the graph that is to be layouted by this context.
      Parameters:
      graph - The Graph to layout.

    • getNodes

      public org.eclipse.gef.graph.Node[] getNodes()
      Returns all the nodes that should be laid out. Replacing elements in the returned array does not affect this context.
      Returns:
      array of nodes to lay out

    • getEdges

      public org.eclipse.gef.graph.Edge[] getEdges()
      Returns all the connections between nodes that should be laid out. Replacing elements in the returned array does not affect this context.
      Returns:
      array of connections between nodes

    • getLayoutAlgorithm

      public ILayoutAlgorithm getLayoutAlgorithm()
      Returns the static layout algorithm used to layout a newly initialized graph or after heavy changes to it.
      Returns:
      The layout algorithm that is used by this LayoutContext.

    • isLayoutIrrelevant

      public boolean isLayoutIrrelevant(org.eclipse.gef.graph.Edge edge)
      Returns true when the given Edge is not relevant for layout according to the configured layout filters. Otherwise returns false.
      Parameters:
      edge - The Edge in question.
      Returns:
      true when the given Edge is not relevant for layout according to the configure layout filters, otherwise false.

    • isLayoutIrrelevant

      public boolean isLayoutIrrelevant(org.eclipse.gef.graph.Node nodeLayout)
      Returns true when the given Node is not relevant for layout according to the configured layout filters. Otherwise returns false.
      Parameters:
      nodeLayout - The Node in question.
      Returns:
      true when the given Node is not relevant for layout according to the configure layout filters, otherwise false.

    • layoutAlgorithmProperty

      public javafx.beans.property.ObjectProperty<ILayoutAlgorithm> layoutAlgorithmProperty()
      A property representing the layout algorithm used by this LayoutContext.
      See Also:

    • removeLayoutFilter

      public void removeLayoutFilter(ILayoutFilter layoutFilter)
      Removes the given ILayoutFilter from this LayoutContext.
      Parameters:
      layoutFilter - The ILayoutFilter to remove to this context.

    • schedulePostLayoutPass

      public void schedulePostLayoutPass(Runnable runnable)
      Adds the given Runnable to the list of runnables which are called when this LayoutContext is asked to apply all changes made to its elements to the display.
      Parameters:
      runnable - A Runnable called whenever this context is asked to apply all changes made to its elements to the display.

    • schedulePreLayoutPass

      public void schedulePreLayoutPass(Runnable runnable)
      Adds the given Runnable to the list of Runnables which are executed before applying a layout, i.e. before applyLayout(boolean).
      Parameters:
      runnable - The Runnable to add to the list of Runnables which are executed before applying a layout.

    • setLayoutAlgorithm

      public void setLayoutAlgorithm(ILayoutAlgorithm algorithm)
      Sets the layout algorithm for this context.
      Parameters:
      algorithm - The new ILayoutAlgorithm for this LayoutContext.

    • unschedulePostLayoutPass

      public void unschedulePostLayoutPass(Runnable runnable)
      Removes the given Runnable from the list of runnables which are called when this LayoutContext is asked to apply all changes made to its elements to the display.
      Parameters:
      runnable - The Runnable that should no longer get called when flushing changes.

    • unschedulePreLayoutPass

      public void unschedulePreLayoutPass(Runnable runnable)
      Removes the given Runnable from the list of Runnables which are executed before applying a layout, i.e. before applyLayout(boolean).
      Parameters:
      runnable - The Runnable to remove from the list of Runnables which are executed before applying a layout.