#眉標=AJAX
#副標=AJAX開發工具（12）
#大標=實作GWT排序換頁資料表
#作者=文圖／沈炳宏


==<box>===========
程式1
public class TableColumn implements 
IsSerializable {
	private String name;
	private String title;	
	public TableColumn() {
	}	
	public TableColumn(String name, String title) {
		this.name = name;
		this.title = title;
	}    
    getter()...
	setter()...
==<end>==============



==<box>===========
程式2
public class DataFilter implements IsSerializable {
	private String column;
	private String value;
	public DataFilter() {
	}
	public DataFilter(String column, String value) {
		this.column = column;
		this.value = value;
	}
    getter()...
    setter()...
==<end>==============



==<box>===========
程式3
import com.google.gwt.user.client.rpc.
RemoteService;
public interface TableModelService 
extends RemoteService {
	public TableColumn[] getColumns();
	public int getRowsCount(DataFilter[] filters);
	public String[][] getRows(
int startRow, int rowsCount,
DataFilter[] filters, String sortColumn, 
boolean sortOrder);
}
==<end>==============



==<box>===========
程式4
import com.google.gwt.user.client.rpc.
AsyncCallback;
public interface TableModelServiceAsync {
	public void getColumns(
AsyncCallback callback);
	public void getRowsCount(
DataFilter[] filters, AsyncCallback callback);
	public void getRows(
int startRow, int rowsCount,
DataFilter[] filters, String sortColumn, 
boolean sortOrder, 
AsyncCallback callback);
}
==<end>==============



==<box>===========
程式5
public class User {
	private int id;
	private String firstName;
	private String lastName;
	
	public User(int id, String firstName, 
String lastName) {
		this.id = id;
		this.firstName = firstName;
		this.lastName = lastName;
	}
getter()...
setter()...
==<end>==============



==<box>===========
程式6
import java.util.Comparator;
public class UserComparator 
implements Comparator<User> {	
	private String sortColumn;
	private boolean sortingOrder;	
	public UserComparator(
String sortColumn, boolean sortingOrder) {
		this.sortColumn = sortColumn;
		this.sortingOrder = sortingOrder;
	}
	public int compare(User user1, User user2) {
		Comparable column1 = (Comparable)
			ReflectionUtils.getPropertyValue(
			user1, this.sortColumn);
		Comparable column2 = (Comparable)
			ReflectionUtils.getPropertyValue(
			user2, this.sortColumn);
		int compareResult = -1;
		if (column1 != null) {
			if (column2 != null) {
compareResult = column1.compareTo(column2);
			} else {
				compareResult = 1;
			}
		}		 
		if (!this.sortingOrder) {
			compareResult = -1 * compareResult;
		}
		return compareResult;
	}	
}
==<end>==============




==<box>===========
程式7
public class UsersTableModelServiceImpl 
extends RemoteServiceServlet implements
		TableModelService {
private TableColumn[] columns = 
new TableColumn[] {
...
 };

private User[] allUsers = new User[] { 	... };
...
	public TableColumn[] getColumns() {
		return this.columns;
	}
	public int getRowsCount(DataFilter[] filters) {
		...
	}
public String[][] getRows(int startRow, int rowsCount,
DataFilter[] filters, String sortColumn, 
boolean sortingOrder) {	... }

private User[] getRowsData(int startRow, 
int rowsCount,DataFilter[] filters, String sortColumn,
boolean sortingOrder) {
		applyDataFilters(filters);
		applySorting(sortColumn, sortingOrder);
		...
	}
private void applyDataFilters(DataFilter[] filters) {...}
private void applySorting(String sortColumn, 
boolean sortingOrder) {	... }
==<end>==============



==<box>===========
程式8
public AdvancedTable() {		
		final FlowPanel contentFlowPanel = 
new FlowPanel();
		initWidget(contentFlowPanel);		
		grid = new Grid();
		…
		contentFlowPanel.add(grid);		
		final HorizontalPanel navigationPanel = 
new HorizontalPanel();
		contentFlowPanel.add(navigationPanel);
		…
		final Button buttonRefresh = new Button();
		navigationPanel.add(buttonRefresh);
		…		
		statusLabel = new Label();
		navigationPanel.add(statusLabel);
		…
		buttonFirstPage = new Button();
		navigationPanel.add(buttonFirstPage);
		…
		buttonPrevPage = new Button();
		navigationPanel.add(buttonPrevPage);
		…
		buttonNextPage = new Button();
		navigationPanel.add(buttonNextPage);
		…
		buttonLastPage = new Button();
		navigationPanel.add(buttonLastPage);
		…		
	}
==<end>==============




==<box>===========
程式9
private void buttonFirstPageClicked() {
		this.currentPageIndex = 0;
		this.updateRows();		
	}
private void buttonPrevPageClicked() {
		if (this.currentPageIndex > 0) {
			this.currentPageIndex--;
			this.updateRows();	
		}			
	}
private void buttonNextPageClicked() {
		int pagesCount = calcPagesCount();
		if (this.currentPageIndex < pagesCount-1) {
			this.currentPageIndex++;
			this.updateRows();	
		}
	}
private void buttonLastPageClicked() {
		int pagesCount = calcPagesCount();
		this.currentPageIndex = pagesCount;
		this.updateRows();
	}
==<end>==============




==<box>===========
程式10
private void updateRows() {		
		int pagesCount = calcPagesCount();
		if (this.currentPageIndex >= pagesCount) {
			this.currentPageIndex = pagesCount-1;
		} 
		this.currentPageStartRow = 
this.currentPageIndex * this.pageSize;
		this.currentPageRowsCount = 
this.pageSize;
		if (this.currentPageStartRow+
this.currentPageRowsCount > this.totalRowsCount) {
			this.currentPageRowsCount = 
this.totalRowsCount % this.pageSize;
		}
		this.tableModelService.getRows(
				this.currentPageStartRow, 
this.currentPageRowsCount,
				this.filters, this.sortColumnName, 
this.sortOrder, 
				new AsyncCallback() {
			public void onFailure(Throwable caught) {
…
			}
			public void onSuccess(Object result) {
AdvancedTable.this.pageRows = (String[][]) result;
AdvancedTable.this.redrawRows();
			}
		});
	}
==<end>==============




==<box>===========
程式11
	private void cellClicked(
int row, int column) {
if (row == 0) {
			String columnName = 
this.columns[column].getName();
			this.applySorting(columnName);
		} else {
if (row <= this.currentPageRowsCount) {
				selectRow(row);
			}
		}
		redrawSelectedRow();
	}
==<end>==============




==<box>===========
程式12
	private void applySorting(String column) {
		if (column.equals(this.sortColumnName)) {
			applySorting(this.sortColumnName, 
! this.sortOrder);
		} 
		else {
			applySorting(column, true);
		}
	}
	public void applySorting(String sortColumnName, 
boolean sortOrder) {
		this.sortColumnName = sortColumnName;
		this.sortOrder = sortOrder;
		redrawColumnTitles();
		updateRows();
	}
	private void redrawColumnTitles() {
		for (int col=0; col<this.columns.length; col++) {
			TableColumn column = this.columns[col];
			String title = column.getTitle();
if (column.getName().equals(this.sortColumnName)) {
				if (this.sortOrder) {
title = title + SORT_ASC_SYMBOL;
				}
				else {
title = title + SORT_DESC_SYMBOL;
				}
			}
			grid.setText(0, col, title);
		}
	}
==<end>==============




==<box>===========
程式13
public void onClick(Widget sender) {
String filterText = textBoxFilter.getText();
DataFilter filter = new DataFilter
("keyword", filterText); 
DataFilter[] filters = {filter};
table.applyFilters(filters);
labelMessages.setText
("套用過濾器: '" + filterText +"'.");
}
==<end>==============




==<box>===========
程式14
	public void updateTableData() {		
		this.currentPageIndex = 0;
		grid.resizeRows(1 + this.pageSize);		
		this.updateRowsCount(new AsyncCallback() {
			public void onFailure(Throwable caught) {
			}
			public void onSuccess(Object result) {
				AdvancedTable.this.updateRows();
			}
		});
	}
==<end>==============