Class VFXGridSkin<T, C extends VFXCell<T>>

java.lang.Object

javafx.scene.control.SkinBase<VFXGrid<T,C>>

io.github.palexdev.mfxcore.controls.MFXSkinBase<VFXGrid<T,C>>

io.github.palexdev.virtualizedfx.grid.VFXGridSkin<T,C>

All Implemented Interfaces:

Skin<VFXGrid<T,C>>

public class VFXGridSkin<T, C extends VFXCell<T>>
extends io.github.palexdev.mfxcore.controls.MFXSkinBase<VFXGrid<T,C>>

Default skin implementation for VFXGrid, extends MFXSkinBase and expects behaviors of type VFXGridManager.

The layout is quite simple: there is just one node, called the 'viewport', that is the Pane resposnible for containing and laying out the cells. Needless to say, the layout strategy is custom, and it's defined in the layout() method.

Compared to other virtualized components' skin, this implements a rather unique feature. It allows you, by setting the VFXGrid.alignmentProperty(), to change the x and y coordinates of the viewport node. This is especially useful if you want the content to be centered and in combination with VFXGrid.autoArrange(int) (think about a gallery, for example).

As all skins typically do, this is also responsible for catching any change in the component's properties. The computation that leads to a new state is delegated to the controller/behavior, which is the VFXGridManager. Read this addListeners() to check which changes are handled.

Last but not least, by design, this skin makes the component always be at least 100px tall and wide. You can change this by overriding the DEFAULT_SIZE variable.

Field Summary

Fields

Modifier and Type	Field	Description
protected double	DEFAULT_SIZE
protected final Pane	viewport

Constructor Summary

Constructors

Constructor	Description
VFXGridSkin(VFXGrid<T,C> grid)

Method Summary

Modifier and Type	Method	Description
protected void	addListeners()	Adds listeners on the component's properties which need to produce a new VFXGridState upon changing.
protected double	computeMinHeight(double width, double topInset, double rightInset, double bottomInset, double leftInset)
protected double	computeMinWidth(double height, double topInset, double rightInset, double bottomInset, double leftInset)
void	dispose()
protected VFXGridManager<T,C>	getBehavior()
protected void	layout()	Core method responsible for resizing and positioning cells in the viewport.
protected void	layoutChildren(double x, double y, double w, double h)
protected void	onLayoutCompleted(boolean done)	This method is crucial because it resets the VFXGrid.needsViewportLayoutProperty() to false.

Methods inherited from class io.github.palexdev.mfxcore.controls.MFXSkinBase

events, getBehaviorAs, getControl, listeners, registerBehavior

Methods inherited from class javafx.scene.control.SkinBase

computeBaselineOffset, computeMaxHeight, computeMaxWidth, computePrefHeight, computePrefWidth, consumeMouseEvents, executeAccessibleAction, getChildren, getClassCssMetaData, getCssMetaData, getNode, getSkinnable, layoutInArea, layoutInArea, layoutInArea, positionInArea, positionInArea, pseudoClassStateChanged, queryAccessibleAttribute, registerChangeListener, registerInvalidationListener, registerListChangeListener, snappedBottomInset, snappedLeftInset, snappedRightInset, snappedTopInset, snapPosition, snapPositionX, snapPositionY, snapSize, snapSizeX, snapSizeY, snapSpace, snapSpaceX, snapSpaceY, unregisterChangeListeners, unregisterInvalidationListeners, unregisterListChangeListeners

Methods inherited from class java.lang.Object

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

Methods inherited from interface javafx.scene.control.Skin

install

Field Details

viewport

protected final Pane viewport

DEFAULT_SIZE

protected double DEFAULT_SIZE

Constructor Details

VFXGridSkin

public VFXGridSkin(VFXGrid<T,C> grid)

Method Details

addListeners

protected void addListeners()

Adds listeners on the component's properties which need to produce a new VFXGridState upon changing.

Here's the list:

- Listener on VFXGrid.stateProperty(), this is crucial to update the viewport's children and invoke VFXGrid.requestViewportLayout() if VFXGridState.haveCellsChanged() is true

- Listener on VFXGrid.needsViewportLayoutProperty(), this is crucial because invokes layout()

- Listener on VFXGrid.helperProperty(), this is crucial because it's responsible for binding the viewport's translate properties to the VFXContainerHelper.viewportPositionProperty() By translating the viewport, we give the illusion of scrolling (virtual scrolling)

- Listener on Region.widthProperty(), will invoke VFXGridManager.onGeometryChanged()

- Listener on VFXGrid.helperProperty(), will invoke VFXGridManager.onGeometryChanged()

- Listener on VFXGrid.bufferSizeProperty(), will invoke VFXGridManager.onGeometryChanged(). Yes, it is enough to threat this change as a geometry change to avoid code duplication

-Listener on VFXGrid.vPosProperty(), will invoke VFXGridManager.onPositionChanged(Orientation) with Orientation.VERTICAL as parameter

-Listener on VFXGrid.hPosProperty(), will invoke VFXGridManager.onPositionChanged(Orientation) with Orientation.HORIZONTAL as parameter

- Listener on VFXGrid.columnsNumProperty(), will invoke VFXGridManager.onColumnsNumChanged()

- Listener on VFXGrid.getCellFactory(), will invoke VFXGridManager.onCellFactoryChanged()

- Listener on VFXGrid.cellSizeProperty(), will invoke VFXGridManager.onCellSizeChanged()

- Listener on VFXGrid.vSpacingProperty(), will invoke VFXGridManager.onSpacingChanged()

- Listener on VFXGrid.hSpacingProperty(), will invoke VFXGridManager.onSpacingChanged()

- Listener on VFXGrid.itemsProperty(), will invoke VFXGridManager.onItemsChanged()

- Listener on VFXGrid.alignmentProperty(), will invoke Parent.requestLayout()

layout

protected void layout()

Core method responsible for resizing and positioning cells in the viewport. This method will not execute if the layout was not requested, VFXGrid.needsViewportLayoutProperty() is false, or if the VFXGrid.stateProperty() is VFXGridState.INVALID.

In any case, at the end of the method, onLayoutCompleted(boolean) will be called.

Cells are retrieved from the current grid's state, given by the VFXGrid.stateProperty(). The iteration over each row and column gives us all the indexes to retrieve the cells from VFXGridState.getCellsByIndex(). For the actual layout, however, we use two counters because the layout is 'absolute'. Meaning that the row and column indexes are irrelevant for the cell's position, we just care about which comes before/after, above/below. Make sure to also read VFXGridState to understand how indexes are managed for the VFXGrid. In other words, it doesn't matter whether our range is [1, 5] or [4, 6] or whatever, the layout index will always start from 0 and increment towards the end of the range.

The layout is performed by VFXGridHelper.layout(int, int, VFXCell), the two aforementioned counters are passed as arguments.

 
 Little example:
 For a rows range of [2, 7] and columns range of [2, 7]
 The first cell's coordinates are [2, 2], but its layout coordinates are [0, 0]
 The second cell's coordinates are [2, 3], but its layout coordinates are [0, 1]
 ...and so on
 
 

See Also:

• onLayoutCompleted(boolean)

onLayoutCompleted

protected void onLayoutCompleted(boolean done)

This method is crucial because it resets the VFXGrid.needsViewportLayoutProperty() to false. If you override this method or the layout(), remember to call this!

Parameters:

done - this parameter can be useful to overriders as it gives information on whether the layout() was executed correctly

computeMinWidth

protected double computeMinWidth(double height,
 double topInset,
 double rightInset,
 double bottomInset,
 double leftInset)

Overrides:

computeMinWidth in class SkinBase<VFXGrid<T, C extends VFXCell<T>>>

computeMinHeight

protected double computeMinHeight(double width,
 double topInset,
 double rightInset,
 double bottomInset,
 double leftInset)

Overrides:

computeMinHeight in class SkinBase<VFXGrid<T, C extends VFXCell<T>>>

layoutChildren

protected void layoutChildren(double x,
 double y,
 double w,
 double h)

Overrides:

layoutChildren in class SkinBase<VFXGrid<T, C extends VFXCell<T>>>

dispose

public void dispose()

Specified by:

dispose in interface Skin<T>

Overrides:

dispose in class io.github.palexdev.mfxcore.controls.MFXSkinBase<VFXGrid<T, C extends VFXCell<T>>>

getBehavior

protected VFXGridManager<T,C> getBehavior()

Overrides:

getBehavior in class io.github.palexdev.mfxcore.controls.MFXSkinBase<VFXGrid<T, C extends VFXCell<T>>>