org.zkoss.zul.impl
Class GridDataLoader

java.lang.Object
  org.zkoss.zul.impl.GridDataLoader

All Implemented Interfaces:

Cropper, DataLoader

Direct Known Subclasses:

LiveGridDataLoader

public class GridDataLoader
extends java.lang.Object
implements DataLoader, Cropper

Generic Grid data loader.

Since:

5.0.0

Author:

henrichen

Constructor Summary

GridDataLoader()

Method Summary

void	doListDataChange(ListDataEvent event) Handle event when ListDataEvent is fired from owner component.
java.util.Set<? extends Component>	getAvailableAtClient() Returns a set of child components that are available at the client, or null if ALL available.
protected java.util.Set<? extends Component>	getAvailableAtClient(int offset, int limit)
Component	getCropOwner() Returns the owner of the cropping scope.
int	getLimit() Returns the required visible limit size of the current loaded data chunk to be shown on the screen.
int	getOffset() Returns the requested visible offset of the current loaded data chunk.
Component	getOwner() Returns the associated owner component of this DataLoader.
java.lang.Object	getRealRenderer() Return the renderer to do rendering.
int	getTotalSize() Returns the total size of the data.
void	init(Component owner, int offset, int limit) Callback from the owner component and give a chance to initialize things.
protected boolean	inPagingMold()
boolean	isCropper() Returns whether it is a cropper, i.e., cropping is applied.
protected Component	newUnloadedItem(java.lang.Object renderer, int index) Creates a new and unloaded row.
void	reset() Callback from the owner component and give a chance to reset things.
void	setLoadAll(boolean b) Sets whether to always load all items from ListModel.
void	syncModel(int offset, int limit) Synchronizes the owner component to be consistent with the specified model.
void	updateModelInfo() Used to update some extra control information to the client.

Methods inherited from class java.lang.Object

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

Constructor Detail

GridDataLoader

public GridDataLoader()

Method Detail

init

public void init(Component owner,
                 int offset,
                 int limit)

Description copied from interface: DataLoader

Callback from the owner component and give a chance to initialize things.

Specified by:

init in interface DataLoader

Parameters:

owner - the owner component of this DataLoader.

reset

public void reset()

Description copied from interface: DataLoader

Callback from the owner component and give a chance to reset things.

Specified by:

reset in interface DataLoader

getOwner

public final Component getOwner()

Description copied from interface: DataLoader

Returns the associated owner component of this DataLoader.

Specified by:

getOwner in interface DataLoader

getOffset

public int getOffset()

Description copied from interface: DataLoader

Returns the requested visible offset of the current loaded data chunk.

Specified by:

getOffset in interface DataLoader

Returns:

the requested visible offset of the current loaded data chunk.

getLimit

public int getLimit()

Description copied from interface: DataLoader

Returns the required visible limit size of the current loaded data chunk to be shown on the screen.

Specified by:

getLimit in interface DataLoader

Returns:

the required visible limit size of the current loaded data chunk to be shown on the screen.

getTotalSize

public int getTotalSize()

Description copied from interface: DataLoader

Returns the total size of the data.

Specified by:

getTotalSize in interface DataLoader

Returns:

the total size of the data.

doListDataChange

public void doListDataChange(ListDataEvent event)

Description copied from interface: DataLoader

Handle event when ListDataEvent is fired from owner component.

Specified by:

doListDataChange in interface DataLoader

newUnloadedItem

protected Component newUnloadedItem(java.lang.Object renderer,
                                    int index)

Creates a new and unloaded row.

getRealRenderer

public java.lang.Object getRealRenderer()

Description copied from interface: DataLoader

Return the renderer to do rendering.

Specified by:

getRealRenderer in interface DataLoader

syncModel

public void syncModel(int offset,
                      int limit)

Description copied from interface: DataLoader

Synchronizes the owner component to be consistent with the specified model.

Specified by:

syncModel in interface DataLoader

Parameters:

offset - the starting index of the range to do data synchronize.

limit - the size of the range to do data synchronize. -1 means the current range.

inPagingMold

protected boolean inPagingMold()

updateModelInfo

public void updateModelInfo()

Description copied from interface: DataLoader

Used to update some extra control information to the client.

Specified by:

updateModelInfo in interface DataLoader

setLoadAll

public void setLoadAll(boolean b)

Description copied from interface: DataLoader

Sets whether to always load all items from ListModel.

Specified by:

setLoadAll in interface DataLoader

isCropper

public boolean isCropper()

Description copied from interface: Cropper

Returns whether it is a cropper, i.e., cropping is applied.

Note: this method is called when an child is detached, so you have to count one more for the total number of children. Example <= must be used, not <:
getChildCount() <= getPageSize()

The result of returning false is the same as not declaring with Cropper.

Specified by:

isCropper in interface Cropper

getAvailableAtClient

public java.util.Set<? extends Component> getAvailableAtClient()

Description copied from interface: Cropper

Returns a set of child components that are available at the client, or null if ALL available. The child components in the returned set must be in the same order of Component.getChildren(). In order words, you must use LinkedHashSet or similar to ensure the order in the returned set.

Note: for better performance, it is better to return null if all children are available at the client.

Note: the components in the returned set can have different parents. It is useful if you want to implement multi-level cropping, such as tree. Refer to Cropper.getCropOwner().

Specified by:

getAvailableAtClient in interface Cropper

getAvailableAtClient

protected java.util.Set<? extends Component> getAvailableAtClient(int offset,
                                                                  int limit)

getCropOwner

public Component getCropOwner()

Description copied from interface: Cropper

Returns the owner of the cropping scope. In most cases, Cropper.getAvailableAtClient() returns only the available direct children of this component, and this method returns this component. It is so-called a single-level cropping, such as listbox and tree.

If you want to implement multi-level cropping, such as tree, you can consider the whole tree as a cropping scope. And, Cropper.getAvailableAtClient() returns all available items, not just the child of this component. In additions, this method returns the tree.

Specified by:

getCropOwner in interface Cropper