Package org.eclipse.nebula.widgets.nattable.layer

Interface ILayer

All Superinterfaces:
ILayerListener, IPersistable
All Known Subinterfaces:
IUniqueIndexLayer
All Known Implementing Classes:
_001_Getting_Started.BodyLayerStack, _001_Getting_Started.ColumnHeaderLayerStack, _001_Getting_Started.RowHeaderLayerStack, _804_GlazedListsEditorExample.GlazedListsEditorColumnHeaderLayerStack, AbstractColumnHideShowLayer, AbstractIndexLayerTransform, AbstractLayer, AbstractLayerTransform, AbstractRowHideShowLayer, BaseColumnReorderLayerFixture, BaseDataLayerFixture, BaseDataLayerFixture, BaseRowReorderLayerFixture, BlinkLayer, BodyLayerStackFixture, ColumnGroupBodyLayerStack, ColumnGroupExpandCollapseLayer, ColumnGroupExpandCollapseLayer, ColumnGroupGroupHeaderLayer, ColumnGroupHeaderLayer, ColumnGroupHeaderLayer, ColumnGroupReorderLayer, ColumnHeaderLayer, ColumnHeaderLayerFixture, ColumnHideShowLayer, ColumnHideShowLayerFixture, ColumnReorderLayer, ColumnReorderLayerFixture, ColumnStructureUpdatesExampleGridLayer, ComboBoxFilterRowHeaderComposite, CompositeFreezeLayer, CompositeLayer, CompositeLayerFixture, CornerLayer, DataChangeLayer, DataLayer, DataLayerFixture, DataLayerFixture, DefaultBodyLayerStack, DefaultColumnHeaderDataLayer, DefaultGridLayer, DefaultRowHeaderDataLayer, DetailGlazedListsEventLayer, DimensionallyDependentIndexLayer, DimensionallyDependentLayer, DummyGridLayerStack, FilterRowDataLayer, FilterRowExampleGridLayer, FilterRowHeaderComposite, FixedSummaryRowHeaderLayer, FixedSummaryRowLayer, FreezeLayer, FullFeaturedBodyLayerStack, FullFeaturedColumnHeaderLayerStack, GenericLayerFixture, GlazedListsColumnHeaderLayerStack, GlazedListsEventLayer, GlazedListsGridLayer, GlazedListsGridLayer, GlazedListsRowHideShowLayer, GridLayer, GridLayerFixture, GroupByDataLayer, GroupByHeaderLayer, HierarchicalTreeLayer, HoverLayer, InvertedLayer, NatTable, NatTableFixture, NatTableFixture, ResizeColumnHideShowLayer, RowGroupExpandCollapseLayer, RowGroupExpandCollapseLayer, RowGroupHeaderLayer, RowGroupHeaderLayer, RowHeaderLayer, RowHideShowLayer, RowHideShowLayerFixture, RowIdHideShowLayer, RowReorderLayer, RowReorderLayerFixture, SelectionExampleBodyLayerStack, SelectionExampleGridLayer, SelectionLayer, SortHeaderLayer, SpanningDataLayer, StaticFilterExampleGridLayer, SummaryRowLayer, TestLayer, TreeLayer, ViewportLayer, ViewportLayerFixture, ViewportLayerFixture
public interface ILayer extends ILayerListener, IPersistable

A Layer is a rectangular region of grid cells. A layer has methods to access its columns, rows, width and height. A layer can be stacked on top of another layer in order to expose a transformed view of its underlying layer's grid cell structure.

Columns and rows in a layer are referenced either by position or index. The position of a column/row in a layer corresponds to the physical location of the column/row in the layer. The index of a column/row in a layer corresponds to the location of the column/row in the lowest level layer in the layer stack. These concepts are illustrated by the following example: 

 Hide Layer C
 0 1 2 3 4 <- column positions
 1 0 3 4 5 <- column indexes

 Reorder Layer B
 0 1 2 3 4 5 <- column positions
 2 1 0 3 4 5 <- column indexes

 Data Layer A
 0 1 2 3 4 5 <- column positions
 0 1 2 3 4 5 <- column indexes

In the above example, Hide Layer C is stacked on top of Reorder Layer B, which is in turn stacked on top of Data Layer A. The positions in Data Layer A are the same as its indexes, because it is the lowest level layer in the stack. Reorder Layer B reorders column 0 of its underlying layer (Data Layer A) after column 2 of its underlying layer. Hide Layer C hides the first column of its underlying layer (Reorder Layer B).

Layers can also be laterally composed into larger layers. For instance, the standard grid layer is composed of a body layer, column header layer, row header layer, and corner layer:

layer composition
corner column header
row header body
See Also:

  • Method Details

    • dispose

      void dispose()
      Dispose any resource allocated by this layer.

    • registerPersistable

      void registerPersistable(IPersistable persistable)
      Register an IPersistable that can write its state to the state Properties instance when the layer is persisted.
      Parameters:
      persistable - The persistable that should be registered.

    • unregisterPersistable

      void unregisterPersistable(IPersistable persistable)
      Unregister the given IPersistable.
      Parameters:
      persistable - The persistable to unregister.

    • configure

      void configure(IConfigRegistry configRegistry, UiBindingRegistry uiBindingRegistry)
      Configure this layer, e.g. add any key/mouse bindings and other general configuration.

      This method is triggered by NatTable.configure() and executed down the layer stack.

      Parameters:
      configRegistry - The IConfigRegistry instance owned by the NatTable this layer is attached to.
      uiBindingRegistry - The UiBindingRegistry instance owned by NatTable this layer is attached to.
      Since:
      2.0

    • getRegionLabelsByXY

      LabelStack getRegionLabelsByXY(int x, int y)
      Return the LabelStack containing the region labels for the cell at the given pixel position.
      Parameters:
      x - the x pixel coordinate
      y - the y pixel coordinate
      Returns:
      LabelStack containing the region labels for the cell at the given pixel position.

    • doCommand

      boolean doCommand(ILayerCommand command)
      Opportunity to respond to a command as it flows down the stack. If the layer is not interested in the command it should allow the command to keep traveling down the stack.

      Note: Before the layer can process a command it must convert the command to its local coordinates using ILayerCommand.convertToTargetLayer(ILayer)

      Parameters:
      command - The command to execute.
      Returns:
      true if the command has been handled and was therefore consumed, false otherwise.

    • registerCommandHandler

      void registerCommandHandler(ILayerCommandHandler<?> commandHandler)
      Register an ILayerCommandHandler to handle a command in this layer. Only one ILayerCommandHandler per ILayerCommand can be registered per layer.
      Parameters:
      commandHandler - The command handler to register with this layer.

    • unregisterCommandHandler

      void unregisterCommandHandler(Class<? extends ILayerCommand> commandClass)
      Unregister the ILayerCommandHandler that is registered for the given ILayerCommand class.
      Parameters:
      commandClass - The ILayerCommand class for which the ILayerCommandHandler should be unregistered.

    • fireLayerEvent

      void fireLayerEvent(ILayerEvent event)
      Events can be fired to notify other components of the grid. Events travel up the layer stack and may cause a repaint.

      Example: When the contents of the grid change IVisualChangeEvent can be fired to notify other layers to refresh their caches etc.

      Parameters:
      event - the event to fire

    • addLayerListener

      void addLayerListener(ILayerListener listener)
      Add a general ILayerListener to handle ILayerEvents on this layer.
      Parameters:
      listener - The ILayerListener to add.

    • removeLayerListener

      void removeLayerListener(ILayerListener listener)
      Remove the given ILayerListener from this layer.
      Parameters:
      listener - The ILayerListener to remove.

    • hasLayerListener

      boolean hasLayerListener(Class<? extends ILayerListener> layerListenerClass)
      Check if an ILayerListener of the given type is registered on this layer or not.
      Parameters:
      layerListenerClass - The type of ILayerListener to check for.
      Returns:
      true if this ILayer has a ILayerListener of the specified type registered, false if there is no such listener registered.

    • getLayerPainter

      ILayerPainter getLayerPainter()
      Returns:
      The ILayerPainter used to render this layer.

    • getClientAreaProvider

      IClientAreaProvider getClientAreaProvider()
      Returns:
      The IClientAreaProvider that specifies the rectangular area available on this layer.

    • setClientAreaProvider

      void setClientAreaProvider(IClientAreaProvider clientAreaProvider)
      Parameters:
      clientAreaProvider - The IClientAreaProvider that specifies the rectangular area available on this layer.

    • getColumnCount

      int getColumnCount()
      Returns:
      The number of columns in this layer.

    • getPreferredColumnCount

      int getPreferredColumnCount()

    • getColumnIndexByPosition

      int getColumnIndexByPosition(int columnPosition)
      Gets the underlying non-transformed column index for the given column position on this layer.
      Parameters:
      columnPosition - The column position relative to this layer.
      Returns:
      An underlying non-transformed column index, or -1 if the given column position does not exist within this coordinate system.

    • localToUnderlyingColumnPosition

      int localToUnderlyingColumnPosition(int localColumnPosition)
      Convert a column position to the coordinates of the underlying layer. This is possible since each layer is aware of its underlying layer.
      Parameters:
      localColumnPosition - column position in local (the layer's own) coordinates
      Returns:
      column position in the underlying layer's coordinates

    • underlyingToLocalColumnPosition

      int underlyingToLocalColumnPosition(ILayer sourceUnderlyingLayer, int underlyingColumnPosition)
      Transforms the column position relative to the given underlying layer to this layer coordinates.
      Parameters:
      sourceUnderlyingLayer - The underlying layer to which the given column position matches.
      underlyingColumnPosition - The column position in the given underlying layer that should be converted to a local column position.
      Returns:
      The given column position transformed to be local to this layer.

    • underlyingToLocalColumnPositions

      Collection<Range> underlyingToLocalColumnPositions(ILayer sourceUnderlyingLayer, Collection<Range> underlyingColumnPositionRanges)
      Transforms the column position ranges relative to the given underlying layer to this layer coordinates.
      Parameters:
      sourceUnderlyingLayer - The underlying layer to which the given column positions match.
      underlyingColumnPositionRanges - The column position ranges relative to the given underlying layer that should be converted to local column positions.
      Returns:
      The given column position ranges transformed to this layer.

    • getWidth

      int getWidth()
      Returns the total width in pixels of this layer.
      Returns:
      The total width in pixels of this layer.

    • getPreferredWidth

      int getPreferredWidth()

    • getColumnWidthByPosition

      int getColumnWidthByPosition(int columnPosition)
      Returns the width in pixels of the given column. The width of invisible and non-existing columns is 0.
      Parameters:
      columnPosition - The column position in this layer.
      Returns:
      The width of the column.

    • isColumnPositionResizable

      boolean isColumnPositionResizable(int columnPosition)
      Check if the column at the given position is resizable.
      Parameters:
      columnPosition - The column position to check.
      Returns:
      true if the column is resizable, false if not.

    • getColumnPositionByX

      int getColumnPositionByX(int x)
      Returns the column position that contains the given x coordinate.
      Parameters:
      x - A horizontal pixel location relative to the pixel boundary of this layer.
      Returns:
      A column position relative to the associated coordinate system, or -1 if there is no column that contains x.

    • getStartXOfColumnPosition

      int getStartXOfColumnPosition(int columnPosition)
      Returns the x offset in pixels of the given column.
      Parameters:
      columnPosition - The column position in this layer.
      Returns:
      The x offset of the column, or -1.

    • getUnderlyingLayersByColumnPosition

      Collection<ILayer> getUnderlyingLayersByColumnPosition(int columnPosition)
      Returns the layers that are directly below this layer for the given column position. For simple layers this collection will typically only have one entry. Layer compositions might return multiple values, e.g. in a default grid there will be 2 layers in the collection as there are two layers involved in a column.
      Parameters:
      columnPosition - The column position for which the underlying layers are requested.
      Returns:
      The layers that are directly below this layer for the given column position or null if this layer has no underlying layers.

    • getRowCount

      int getRowCount()
      Returns:
      The number of rows in this layer.

    • getPreferredRowCount

      int getPreferredRowCount()

    • getRowIndexByPosition

      int getRowIndexByPosition(int rowPosition)
      Gets the underlying non-transformed row index for the given row position on this layer.
      Parameters:
      rowPosition - The row position relative to this layer.
      Returns:
      An underlying non-transformed row index, or -1 if the given row position does not exist within this coordinate system.

    • localToUnderlyingRowPosition

      int localToUnderlyingRowPosition(int localRowPosition)
      Convert a row position to the coordinates of the underlying layer. This is possible since each layer is aware of its underlying layer.
      Parameters:
      localRowPosition - row position in local (the layer's own) coordinates
      Returns:
      row position in the underlying layer's coordinates

    • underlyingToLocalRowPosition

      int underlyingToLocalRowPosition(ILayer sourceUnderlyingLayer, int underlyingRowPosition)
      Transforms the row position relative to the given underlying layer to this layer coordinates.
      Parameters:
      sourceUnderlyingLayer - The underlying layer to which the given row position matches.
      underlyingRowPosition - The row position in the given underlying layer that should be converted to a local row position.
      Returns:
      The given row position transformed to be local to this layer.

    • underlyingToLocalRowPositions

      Collection<Range> underlyingToLocalRowPositions(ILayer sourceUnderlyingLayer, Collection<Range> underlyingRowPositionRanges)
      Transforms the row position ranges relative to the given underlying layer to this layer coordinates.
      Parameters:
      sourceUnderlyingLayer - The underlying layer to which the given row positions match.
      underlyingRowPositionRanges - The row position ranges relative to the given underlying layer that should be converted to local row positions.
      Returns:
      The given row position ranges transformed to this layer.

    • getHeight

      int getHeight()
      Returns the total height in pixels of this layer.
      Returns:
      The total height in pixels of this layer.

    • getPreferredHeight

      int getPreferredHeight()

    • getRowHeightByPosition

      int getRowHeightByPosition(int rowPosition)
      Returns the height in pixels of the given row. The height of invisible and non-existing rows is 0.
      Parameters:
      rowPosition - The row position in this layer.
      Returns:
      The height of the row.

    • isRowPositionResizable

      boolean isRowPositionResizable(int rowPosition)
      Check if the row at the given position is resizable.
      Parameters:
      rowPosition - The row position to check.
      Returns:
      true if the row is resizable, false if not.

    • getRowPositionByY

      int getRowPositionByY(int y)
      Returns the row position that contains the given y coordinate.
      Parameters:
      y - a vertical pixel location relative to the pixel boundary of this layer
      Returns:
      a row position relative to the associated coordinate system, or -1 if there is no row that contains y

    • getStartYOfRowPosition

      int getStartYOfRowPosition(int rowPosition)
      Returns the y offset in pixels of the given row.
      Parameters:
      rowPosition - the row position in this layer
      Returns:
      the y offset of the row, or -1

    • getUnderlyingLayersByRowPosition

      Collection<ILayer> getUnderlyingLayersByRowPosition(int rowPosition)
      Returns the layers that are directly below this layer for the given row position. For simple layers this collection will typically only have one entry. Layer compositions might return multiple values, e.g. in a default grid there will be 2 layers in the collection as there are two layers involved in a row.
      Parameters:
      rowPosition - The row position for which the underlying layers are requested.
      Returns:
      The layers that are directly below this layer for the given row position or null if this layer has no underlying layers.

    • getCellByPosition

      ILayerCell getCellByPosition(int columnPosition, int rowPosition)
      Returns the cell for the given coordinates on this layer.
      Parameters:
      columnPosition - The column position of the requested cell.
      rowPosition - The row position of the requested cell.
      Returns:
      The ILayerCell for the given coordinates in this layer or null if the coordinates are invalid on this layer.

    • getBoundsByPosition

      org.eclipse.swt.graphics.Rectangle getBoundsByPosition(int columnPosition, int rowPosition)
      Calculates the bounds in pixel for the given cell position.
      Parameters:
      columnPosition - the column position of the cell
      rowPosition - the row position of the cell
      Returns:
      the bounds, or null if there are no valid bounds

    • getDisplayModeByPosition

      DisplayMode getDisplayModeByPosition(int columnPosition, int rowPosition)
      Returns the active DisplayMode for the cell at the given coordinates. Needed to retrieve the corresponding configurations out of the IConfigRegistry. The default value is DisplayMode.NORMAL. The SelectionLayer for example overrides this to return DisplayMode.SELECT for cells that are currently selected.
      Parameters:
      columnPosition - The column position of the cell.
      rowPosition - The row position of the cell.
      Returns:
      DisplayMode for the cell at the given coordinates.
      Since:
      2.0

    • getConfigLabelsByPosition

      LabelStack getConfigLabelsByPosition(int columnPosition, int rowPosition)
      Returns the config labels for the cell at the given coordinates. Needed to retrieve the corresponding configurations out of the IConfigRegistry.
      Parameters:
      columnPosition - The column position of the cell.
      rowPosition - The row position of the cell.
      Returns:
      The LabelStack with the config labels for the cell at the given coordinates.

    • getDataValueByPosition

      Object getDataValueByPosition(int columnPosition, int rowPosition)
      Returns the data value for the cell at the given coordinates.
      Parameters:
      columnPosition - The column position of the cell.
      rowPosition - The row position of the cell.
      Returns:
      The data value for the cell at the given coordinates.

    • getUnderlyingLayerByPosition

      ILayer getUnderlyingLayerByPosition(int columnPosition, int rowPosition)
      Returns the layer that is directly below this layer for the given cell coordinate.
      Parameters:
      columnPosition - The column position for which the underlying layer is requested.
      rowPosition - The row position for which the underlying layer is requested.
      Returns:
      The layer that is directly below this layer for the given cell coordinates or null if this layer has no underlying layers.

    • getCellPainter

      ICellPainter getCellPainter(int columnPosition, int rowPosition, ILayerCell cell, IConfigRegistry configRegistry)
      Return the ICellPainter for the given ILayerCell at the given coordinates out of the given IConfigRegistry.
      Parameters:
      columnPosition - The column position of the cell.
      rowPosition - The row position of the cell.
      cell - The ILayerCell for which the ICellPainter is requested.
      configRegistry - The IConfigRegistry to retrieve the painter from.
      Returns:
      The ICellPainter for the given cell at the given coordinates or null if no painter is configured.

    • isDynamicSizeLayer

      default boolean isDynamicSizeLayer()
      Returns:
      true if the layer has a dynamic size (e.g. viewport) or a fixed size.
      Since:
      2.0

    • getProvidedLabels

      default Collection<String> getProvidedLabels()
      Returns:
      The collection of labels that are provided by this layer used e.g. for CSS styling.
      Since:
      2.0