558 lines
21 KiB
Java
558 lines
21 KiB
Java
/*
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* Copyright (c) 2003,2009 Declarative Engineering LLC.
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* All rights reserved. This program and the accompanying materials
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* are made available under the terms of the Declarative Engineering LLC
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* verson 1 which accompanies this distribution, and is available at
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* http://declarativeengineering.com/legal/DE_Developer_License_v1.txt
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*/
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package com.foundation.tcv.swt.client;
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import com.common.comparison.Comparator;
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import com.common.util.IIterator;
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import com.common.util.IList;
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import com.common.util.LiteList;
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import com.common.util.optimized.IIntIterator;
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import com.common.util.optimized.IntObjectHashMap;
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import com.foundation.tcv.model.LinkInfo;
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import com.foundation.tcv.swt.*;
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import com.foundation.tcv.swt.client.cell.CellComponent;
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import com.foundation.tcv.view.*;
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import com.foundation.view.LinkData;
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public abstract class CollectionComponent extends ScrollableComponent implements ICollectionComponent, ICellContainer {
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/** The only invalid value for an object identifier. */
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protected static final int INVALID_OBJECT_ID = -1;
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/** Used by the hidden data to identify when the previous value has not yet been assigned a value. */
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protected static final Object UNSET_VALUE = new Object();
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/** Whether the user can type a custom selection. If this is true and the selection attribute is not a String type then the user input must match a list item's text. */
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private boolean allowUserItems = false;
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/** Whether the user is allowed to make multiple selections. */
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private boolean allowMultiSelection = false;
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/** Whether the selection should be automatically sent to the model. */
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private boolean autoSynchronizeSelection = false;
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/** The number of milliseconds of delay before auto synchronizing the selection. */
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private long autoSynchronizeSelectionDelay = 500;
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/** The task that auto synchronizes the selection after a short delay. */
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protected Task autoSynchronizeSelectionTask = null;
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/** Whether to send the double click events to the server for processing. */
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private boolean sendDoubleClick = false;
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/** The collection of HiddenData instances, one for each hidden data holder. */
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private IList hiddenDataSets = new LiteList(10, 20);
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/** Maps the row objects by their unique object identifiers. */
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private IntObjectHashMap rowObjectByObjectIdMap = new IntObjectHashMap(100, 200);
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/** The linkage for the selection related value. */
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private Linkage selectionLinkage = new Linkage();
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/** The collection of cell components. */
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private LiteList cellComponents = null;
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/** The count of calls to preChangeCollection(). Incremented for each call to preChangeCollection(), decremented for each call to postChangeCollection(). This counter determines when to call internalPostChangeCollection(). */
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private int preChangeCollectionCounter = 0;
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/**
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* The base class for the different types of hidden data.
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* Hidden data is used by the collection to activate linkages without going through the controllers or models.
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* Each object in the collection will then be assigned a value for each hidden data and the selection determines the value assigned to the linkages.
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*/
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protected class HiddenData {
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/** The zero based index of the hidden data. This identifies the hidden data that generates events. */
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private int hiddenDataIndex;
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/** The previous selection related value for this hidden data. This allows linkages to be activated only when the value is altered. */
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private Object previousValue = UNSET_VALUE;
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/** The linkage for the selection related value. */
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private Linkage linkage = new Linkage();
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/** The multi-selection options for the hidden data. */
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private int multiSelectionOption = MULTI_SELECTION_OPTION_DEFAULT;
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/** The default value for the hidden data. */
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private Object defaultValue = null;
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/**
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* HiddenData constructor.
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* @param hiddenDataIndex The index in the hidden data set.
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*/
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protected HiddenData(int hiddenDataIndex) {
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this.hiddenDataIndex = hiddenDataIndex;
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}//HiddenData()//
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/**
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* Adds a link associated with the collection's selection's hidden data value.
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* @param link The local linkage for the selection related data.
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*/
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public void addLink(LinkData link) {
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linkage.add(link);
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}//addLink()//
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/**
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* Invokes the linkage with the given value.
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* @param value The last value for the selection and this hidden data.
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*/
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public void invokeLinkage(RowObject[] selections) {
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Object value = null;
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if((selections == null) || (selections.length == 0) || (multiSelectionOption == MULTI_SELECTION_OPTION_DEFAULT)) {
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value = defaultValue;
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}//if//
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else {
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value = selections[0].hiddenData[hiddenDataIndex];
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for(int index = 1; index < selections.length; index++) {
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Object next = selections[index].hiddenData[hiddenDataIndex];
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switch(multiSelectionOption) {
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case MULTI_SELECTION_OPTION_COMMON: {
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//If the values are not comparable then use the default value for the linkage and exit the loop.//
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if(!Comparator.equals(next, value)) {
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value = defaultValue;
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index = selections.length;
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}//if//
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break;
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}//case//
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case MULTI_SELECTION_OPTION_AND: {
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if((next instanceof Boolean) && (value instanceof Boolean)) {
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value = ((Boolean) next).booleanValue() && ((Boolean) value).booleanValue() ? Boolean.TRUE : Boolean.FALSE;
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}//if//
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//TODO: What should we do if they are not booleans? For now we will ignore this since a view building tool would prevent the possibility.
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break;
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}//case//
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case MULTI_SELECTION_OPTION_OR: {
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if((next instanceof Boolean) && (value instanceof Boolean)) {
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value = ((Boolean) next).booleanValue() || ((Boolean) value).booleanValue() ? Boolean.TRUE : Boolean.FALSE;
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}//if//
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//TODO: What should we do if they are not booleans? For now we will ignore this since a view building tool would prevent the possibility.
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break;
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}//case//
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}//switch//
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}//for//
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}//else//
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if(!Comparator.equals(value, previousValue)) {
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previousValue = value;
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linkage.invoke(value);
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}//if//
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}//invokeLinkage()//
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/**
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* Invokes the linkage with the given value.
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* @param value The last value for the selection and this hidden data.
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*/
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public void invokeLinkage(RowObject selection) {
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Object value = selection != null ? selection.hiddenData[hiddenDataIndex] : defaultValue;
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if(!Comparator.equals(value, previousValue)) {
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previousValue = value;
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linkage.invoke(value);
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}//if//
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}//invokeLinkage()//
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/**
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* Gets the index for the hidden data.
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* @return The zero based index identifying the hidden data.
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*/
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public int getHiddenDataIndex() {
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return hiddenDataIndex;
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}//getHiddenDataIndex()//
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}//HiddenData//
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/**
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* CollectionComponent constructor.
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*/
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public CollectionComponent() {
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super();
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}//CollectionComponent()//
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/* (non-Javadoc)
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* @see com.foundation.tcv.swt.client.ICellContainer#addCellComponent(com.foundation.tcv.swt.client.cell.CellComponent)
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*/
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public void addCellComponent(CellComponent component) {
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if(cellComponents == null) {
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cellComponents = new LiteList(10, 20);
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}//if//
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cellComponents.add(component);
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if(isInitialized()) {
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((AbstractComponent) component).internalViewInitializeAll();
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}//if//
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}//addCellComponent()//
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/**
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* Gets the collection of cell components for this container.
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* @return The cell components contained within this container.
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*/
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public IList getCellComponents() {
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return cellComponents == null ? LiteList.EMPTY_LIST : cellComponents;
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}//getCellComponents()//
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/**
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* Gets the SWT composite that represents this collection component.
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* @return The SWT composite providing visualization for this collection component.
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*/
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public org.eclipse.swt.widgets.Composite getSwtComposite() {
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return (org.eclipse.swt.widgets.Composite) getSwtWidget();
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}//getSwtComposite()//
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/* (non-Javadoc)
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* @see com.foundation.tcv.swt.client.ICellContainer#getSwtComposite(com.foundation.tcv.swt.client.RowObject)
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*/
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public org.eclipse.swt.widgets.Composite getSwtComposite(RowObject rowObject) {
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return getSwtComposite();
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}//getSwtComposite()//
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/* (non-Javadoc)
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* @see com.foundation.tcv.swt.client.Component#internalViewInitializeAll()
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*/
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protected void internalViewInitializeAll() {
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super.internalViewInitializeAll();
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if(cellComponents != null) {
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for(int index = 0; index < cellComponents.getSize(); index++) {
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((AbstractComponent) cellComponents.get(index)).internalViewInitializeAll();
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}//for//
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}//if//
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}//internalViewInitializeAll()//
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/* (non-Javadoc)
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* @see com.foundation.tcv.swt.client.Component#internalViewReleaseAll()
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*/
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protected void internalViewReleaseAll() {
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super.internalViewReleaseAll();
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if(cellComponents != null) {
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for(int index = 0; index < cellComponents.getSize(); index++) {
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((AbstractComponent) cellComponents.get(index)).internalViewReleaseAll();
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}//for//
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}//if//
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}//internalViewReleaseAll()//
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/* (non-Javadoc)
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* @see com.foundation.tcv.swt.client.Component#internalViewSynchronizeAll()
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*/
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protected void internalViewSynchronizeAll() {
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super.internalViewSynchronizeAll();
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if(cellComponents != null) {
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for(int index = 0; index < cellComponents.getSize(); index++) {
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((AbstractComponent) cellComponents.get(index)).internalViewSynchronizeAll();
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}//for//
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}//if//
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}//internalViewSynchronizeAll()//
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/* (non-Javadoc)
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* @see com.foundation.tcv.swt.client.AbstractComponent#internalViewSynchronize()
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*/
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protected void internalViewSynchronize() {
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super.internalViewSynchronize();
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internalViewSynchronizeSelection();
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}//internalViewSynchronize()//
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/**
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* Synchronizes the selection when requested by the view controller.
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*/
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protected void internalViewSynchronizeSelection() {
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if(!getAutoSynchronizeSelection()) {
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synchronizeSelection();
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}//if//
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else {
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synchronized(this) {
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if(autoSynchronizeSelectionTask != null) {
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removeTask(autoSynchronizeSelectionTask);
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autoSynchronizeSelectionTask.execute();
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}//if//
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}//synchronized//
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}//else//
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}//internalViewSynchronizeSelection()//
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/**
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* Synchronizes the selection when the user interacts with the collection.
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*/
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protected abstract void synchronizeSelection();
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/* (non-Javadoc)
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* @see com.foundation.tcv.swt.client.Component#internalViewInitialize()
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*/
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protected void internalViewInitialize() {
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super.internalViewInitialize();
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}//internalViewInitialize()//
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/* (non-Javadoc)
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* @see com.foundation.tcv.swt.client.AbstractComponent#internalViewRelease()
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*/
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protected void internalViewRelease() {
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synchronized(this) {
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if(autoSynchronizeSelectionTask != null) {
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removeTask(autoSynchronizeSelectionTask);
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autoSynchronizeSelectionTask = null;
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}//if//
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}//synchronized//
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super.internalViewRelease();
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}//internalViewRelease()//
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/* (non-Javadoc)
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* @see com.foundation.tcv.swt.client.AbstractComponent#internalProcessMessage(com.foundation.tcv.model.ViewMessage)
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*/
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public Object internalProcessMessage(ViewMessage viewMessage) {
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Object result = null;
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switch(viewMessage.getMessageNumber()) {
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case MESSAGE_SET_AUTO_SYNCHRONIZE_SELECTION: {
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autoSynchronizeSelection = ((Boolean) viewMessage.getMessageData()).booleanValue();
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break;
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}//case//
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case MESSAGE_SET_AUTO_SYNCHRONIZE_SELECTION_DELAY: {
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autoSynchronizeSelectionDelay = ((Long) viewMessage.getMessageData()).longValue();
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break;
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}//case//
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case MESSAGE_SEND_DOUBLE_CLICK: {
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sendDoubleClick = ((Boolean) viewMessage.getMessageData()).booleanValue();
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break;
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}//case//
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case MESSAGE_ADD_HIDDEN_DATA: {
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hiddenDataSets.add(createHiddenData(hiddenDataSets.getSize()));
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break;
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}//case//
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case MESSAGE_ADD_HIDDEN_DATA_LINK: {
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HiddenData hiddenData = (HiddenData) hiddenDataSets.get(viewMessage.getMessageInteger());
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LinkInfo info = (LinkInfo) viewMessage.getMessageData();
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hiddenData.linkage.add(new LinkData(getComponent(info.getComponent()), info.getTarget(), info.getData(), info.isBoolean(), info.invertLogic(), info.nullValue()));
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break;
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}//case//
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case MESSAGE_UPDATE_HIDDEN_DATA_DEFAULT_VALUE: {
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HiddenData hiddenData = (HiddenData) hiddenDataSets.get(viewMessage.getMessageInteger());
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Object defaultValue = viewMessage.getMessageData();
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hiddenData.defaultValue = defaultValue;
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if(isInitialized()) {
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updateSelectionLinks();
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}//if//
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break;
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}//case//
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case MESSAGE_UPDATE_HIDDEN_DATA: {
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Object[] data = (Object[]) viewMessage.getMessageData();
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int objectId = ((Integer) data[0]).intValue();
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int hiddenDataIndex = ((Integer) data[1]).intValue();
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Object hiddenData = data[2];
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updateHiddenData(getRowObject(objectId), hiddenDataIndex, hiddenData);
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break;
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}//case//
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case MESSAGE_ADD_SELECTION_LINK: {
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LinkInfo info = (LinkInfo) viewMessage.getMessageData();
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selectionLinkage.add(new LinkData(getComponent(info.getComponent()), info.getTarget(), info.getData(), info.invertLogic()));
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break;
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}//case//
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case MESSAGE_PRE_CHANGE_COLLECTION: {
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preChangeCollection();
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break;
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}//case//
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case MESSAGE_POST_CHANGE_COLLECTION: {
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postChangeCollection();
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break;
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}//case//
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default: {
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result = super.internalProcessMessage(viewMessage);
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}//default//
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}//switch//
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return result;
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}//internalProcessMessage()//
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/**
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* Determines whether the control allows the user to type in custom items (combobox).
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* @return Whether users will be allowed to type in a custom value.
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*/
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protected boolean getAllowUserItems() {
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return allowUserItems;
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}//getAllowUserItems()//
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/**
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* Determines whether the control allows the user to type in custom items (combobox).
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* @param allowUserItems Whether users will be allowed to type in a custom value.
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*/
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protected void setAllowUserItems(boolean allowUserItems) {
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this.allowUserItems = allowUserItems;
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}//setAllowUserItems()//
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/**
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* Determines whether the control should automatically synchronize all selections.
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* @return Whether selections should automatically get sent to the server.
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*/
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protected boolean getAutoSynchronizeSelection() {
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return autoSynchronizeSelection;
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}//getAutoSynchronizeSelection()//
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/**
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* Gets the delay in milliseconds between the selection event and updating the model.
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* @return The number of milliseconds to wait before updating the model.
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*/
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protected long getAutoSynchronizeSelectionDelay() {
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return autoSynchronizeSelectionDelay;
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}//getAutoSynchronizeSelectionDelay()//
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/**
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* Sets the delay in milliseconds between the selection event and updating the model.
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* @param autoSynchronizeSelectionDelay The number of milliseconds to wait before updating the model.
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*/
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protected void setAutoSynchronizeSelectionDelay(long autoSynchronizeSelectionDelay) {
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this.autoSynchronizeSelectionDelay = autoSynchronizeSelectionDelay;
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}//setAutoSynchronizeSelectionDelay()//
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/**
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* Gets the linkage for the selection state.
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* @return The linkage used to notify listeners when there is or is not a selection.
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*/
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protected Linkage getSelectionLinkage() {
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return selectionLinkage;
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}//getSelectionLinkage()//
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/**
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* Determines whether the control allows the user to make multiple selections at one time.
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* @return Whether more than one value can be selected at a time.
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*/
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protected boolean getAllowMultiSelection() {
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return allowMultiSelection;
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}//getAllowMultiSelection()//
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/**
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* Determines whether the control allows the user to make multiple selections at one time.
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* @param allowMultiSelection Whether more than one value can be selected at a time.
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*/
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protected void setAllowMultiSelection(boolean allowMultiSelection) {
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this.allowMultiSelection = allowMultiSelection;
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}//setAllowMultiSelection()//
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/**
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* Determines whether the control should send double click events to the server.
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* @return Whether double click events need to be forwarded to the server for processing.
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*/
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protected boolean getSendDoubleClick() {
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return sendDoubleClick;
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}//getSendDoubleClick()//
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/* (non-Javadoc)
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* @see com.foundation.tcv.swt.client.ICellContainer#getSwtComposites()
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*/
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public IIterator getSwtComposites() {
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return LiteList.EMPTY_LIST.iterator();
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}//getSwtComposites()//
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/* (non-Javadoc)
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* @see com.foundation.tcv.swt.client.ICellContainer#setLayout(com.foundation.tcv.swt.client.Layout)
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*/
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public void setLayout(Layout layout) {
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//Not supported.//
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}//setLayout()//
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/**
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* Determines whether the two texts require swapping.
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* This is used by the sorting code to determine whether rows should be swapped.
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* @param text1 The first text.
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* @param text2 The second text (following the first text).
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* @param reverse Whether the logic should be reversed.
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* @return Whether text1 and text2 require swapping.
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*/
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protected boolean requiresSwap(String text1, String text2, boolean reverse) {
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int compare = Comparator.getNumericStringComparator().compare(text1, text2);
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return reverse ? compare < 0 : compare > 0;
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}//requiresSwap()//
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/**
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* Creates a new hidden data object at the given index in the collection.
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* This can be overloaded to use subclasses which can hold the data associated with the hidden data and the rows of data in the component.
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* @param hiddenDataIndex The index at for the hidden data which will serve to identify it on the server and client.
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*/
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protected HiddenData createHiddenData(int hiddenDataIndex) {
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return new HiddenData(hiddenDataIndex);
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}//createHiddenData()//
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/**
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* Gets the hidden data set for the given index.
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* @param hiddenDataIndex The zero based index for the desired hidden data metadata.
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* @return The metadata describing the hidden data and providing access to the current value for any collection item.
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*/
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protected HiddenData getHiddenData(int hiddenDataIndex) {
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return (HiddenData) hiddenDataSets.get(hiddenDataIndex);
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}//getHiddenData()//
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/**
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* Creates a new row object.
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* @param objectId The identifier for the object that is represented by the row.
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* @return An empty row object.
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*/
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protected RowObject createRowObject(int objectId) {
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return new RowObject(objectId, getHiddenDataCount());
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}//createRowObject()//
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/**
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* Gets the row object containing the data for the object with the given identifier.
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* @param objectId Identifies the object that the row object represents.
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* @return The row object that is the avatar for the object identified by the object id.
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*/
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public RowObject getRowObject(int objectId) {
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return (RowObject) rowObjectByObjectIdMap.get(objectId);
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}//getRowObject()//
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/**
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* Adds a new row object to the collection.
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* @param rowObject The row object to be added.
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*/
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protected void addRowObject(RowObject rowObject) {
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rowObjectByObjectIdMap.put(rowObject.getObjectId(), rowObject);
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}//addRowObject()//
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|
/**
|
|
* Removes a row object from the collection.
|
|
* @param rowObject The row object to be removed.
|
|
*/
|
|
protected void removeRowObject(int rowObjectId) {
|
|
((RowObject) rowObjectByObjectIdMap.remove(rowObjectId)).dispose();
|
|
}//removeRowObject()//
|
|
/**
|
|
* Removes all row objects from the collection.
|
|
*/
|
|
protected void removeRowObjects() {
|
|
IIterator iterator = rowObjectByObjectIdMap.valueIterator();
|
|
|
|
while(iterator.hasNext()) {
|
|
((RowObject) iterator.next()).dispose();
|
|
}//while//
|
|
|
|
rowObjectByObjectIdMap.removeAll();
|
|
}//removeRowObjects()//
|
|
/**
|
|
* Gets an iterator over all the row objects.
|
|
* @return The RowObject iterator.
|
|
*/
|
|
public IIterator getRowObjects() {
|
|
return rowObjectByObjectIdMap.valueIterator();
|
|
}//getRowObjects()//
|
|
/**
|
|
* Gets an iterator over all the row object identifiers.
|
|
* @return The row object identifier iterator.
|
|
*/
|
|
protected IIntIterator getRowObjectIds() {
|
|
return rowObjectByObjectIdMap.keyIterator();
|
|
}//getRowObjectIds()//
|
|
/**
|
|
* Gets the number of hidden data sets used by the collection component.
|
|
* @return The count of hidden data 'columns'.
|
|
*/
|
|
protected int getHiddenDataCount() {
|
|
return hiddenDataSets.getSize();
|
|
}//getHiddenDataCount()//
|
|
/**
|
|
* Gets the number of selections in the component.
|
|
* @return The count of selections.
|
|
*/
|
|
protected abstract int controlGetSelectionCount();
|
|
/**
|
|
* Updates selection linkages associated with the hidden data 'columns' based on the current selection settings.
|
|
*/
|
|
protected void updateSelectionLinks() {
|
|
selectionLinkage.invoke(controlGetSelectionCount() > 0 ? Boolean.TRUE : Boolean.FALSE);
|
|
}//updateSelectionLinks()//
|
|
/**
|
|
* Sets the hidden data for an object displayed in the collection and the hidden data column.
|
|
* @param object The row object representing the object whose hidden data is being set.
|
|
* @param hiddenDataIndex The zero based index of the hidden data column.
|
|
* @param value The new value for the hidden data for the object.
|
|
*/
|
|
protected abstract void updateHiddenData(RowObject object, int hiddenDataIndex, Object value);
|
|
/**
|
|
* Called before the collection of displayed values is modified.
|
|
* This method, in combination with postChangeCollection(), allows the control to be more efficient about its adding of items.
|
|
*/
|
|
protected final void preChangeCollection() {
|
|
if(preChangeCollectionCounter++ == 0) {
|
|
internalPreChangeCollection();
|
|
}//if//
|
|
}//preChangeCollection()//
|
|
/**
|
|
* Called after the collection of displayed values is modified.
|
|
*/
|
|
protected final void postChangeCollection() {
|
|
if(--preChangeCollectionCounter == 0) {
|
|
internalPostChangeCollection();
|
|
}//if//
|
|
}//postChangeCollection()//
|
|
/**
|
|
* Called before the collection of displayed values is modified.
|
|
* This method, in combination with postChangeCollection(), allows the control to be more efficient about its adding of items.
|
|
*/
|
|
protected void internalPreChangeCollection() {
|
|
//Subclasses should override as required.//
|
|
}//preChangeCollection()//
|
|
/**
|
|
* Called after the collection of displayed values is modified.
|
|
*/
|
|
protected void internalPostChangeCollection() {
|
|
//Subclasses should override as required.//
|
|
}//postChangeCollection()//
|
|
}//CollectionComponent// |