com.vaadin.client.widget.escalator

Class FlyweightRow

java.lang.Object

com.vaadin.client.widget.escalator.FlyweightRow

All Implemented Interfaces:

Row

public class FlyweightRow
extends Object
implements Row

An internal implementation of the Row interface.

There is only one instance per Escalator. This is designed to be re-used when rendering rows.

Since:

7.4

Author:

Vaadin Ltd

See Also:

Escalator.AbstractRowContainer.refreshRow(TableRowElement, int)

Constructor Summary

Constructors

Constructor and Description
FlyweightRow()

Method Summary

Modifier and Type	Method and Description
void	addCells(int index, int numberOfColumns) Adds cell representations (i.e.
Iterable<FlyweightCell>	getCells() Returns flyweight cells for the client code to render.
Iterable<FlyweightCell>	getCells(int offset, int numberOfCells) Returns a subrange of flyweight cells for the client code to render.
com.google.gwt.dom.client.TableRowElement	getElement() Gets the root element for this row.
int	getRow() Gets the row index.
Iterable<FlyweightCell>	getUnattachedCells(int offset, int numberOfCells) Returns a subrange of unattached flyweight cells.
void	removeCells(int index, int numberOfColumns) Removes cell representations (i.e.
void	setup(com.google.gwt.dom.client.TableRowElement e, int row, double[] columnWidths) Configure this FlyweightRow for the current use.
boolean	teardown() Tear down the state of the Row.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

FlyweightRow

public FlyweightRow()

Method Detail

setup

public void setup(com.google.gwt.dom.client.TableRowElement e,
                  int row,
                  double[] columnWidths)

Configure this FlyweightRow for the current use. This method is expected to be called multiple times during the Grid's life-cycle.

Parameters:

e - the root element for this row

row - the row index

columnWidths - widths for each column on the row

See Also:

FlyweightRow

teardown

public boolean teardown()

Tear down the state of the Row.

This is an internal check method, to prevent retrieving uninitialized data by calling getRow(), getElement() or getCells() at an improper time.

This should only be used with asserts (" assert flyweightRow.teardown() ") so that the code is never run when asserts aren't enabled.

Returns:

always true

getRow

public int getRow()

Description copied from interface: Row

Gets the row index.

Specified by:

getRow in interface Row

Returns:

the row index

getElement

public com.google.gwt.dom.client.TableRowElement getElement()

Description copied from interface: Row

Gets the root element for this row.

The EscalatorUpdater may update the class names of the element and add inline styles, but may not modify the contained DOM structure.

If you wish to modify the cells within this row element, access them via the List<Cell> objects passed in to EscalatorUpdater.updateCells(Row, List)

Specified by:

getElement in interface Row

Returns:

the root element of the row

addCells

public void addCells(int index,
                     int numberOfColumns)

Adds cell representations (i.e. new columns) for the indicated cell range and updates the subsequent indexing.

Parameters:

index - start index of the range

numberOfColumns - length of the range

removeCells

public void removeCells(int index,
                        int numberOfColumns)

Removes cell representations (i.e. removed columns) from the indicated cell range and updates the subsequent indexing.

Parameters:

index - start index of the range

numberOfColumns - length of the range

getCells

public Iterable<FlyweightCell> getCells()

Returns flyweight cells for the client code to render. The cells get their associated elements from the row element.

Precondition: each cell has a corresponding element in the row

Returns:

an iterable of flyweight cells

See Also:

#setup(TableRowElement, int, int[]), teardown()

getCells

public Iterable<FlyweightCell> getCells(int offset,
                                        int numberOfCells)

Returns a subrange of flyweight cells for the client code to render. The cells get their associated elements from the row element.

Precondition: each cell has a corresponding element in the row

Parameters:

offset - the index of the first cell to return

numberOfCells - the number of cells to return

Returns:

an iterable of flyweight cells

getUnattachedCells

public Iterable<FlyweightCell> getUnattachedCells(int offset,
                                                  int numberOfCells)

Returns a subrange of unattached flyweight cells. Unattached cells do not have elements associated. Note that FlyweightRow does not keep track of whether cells in actuality have corresponding DOM elements or not; it is the caller's responsibility to invoke this method with correct parameters.

Precondition: the range [offset, offset + numberOfCells) must be valid

Parameters:

offset - the index of the first cell to return

numberOfCells - the number of cells to return

Returns:

an iterable of flyweight cells