Eclipse Rcp系列三 进一步了解Viewer

好在二的基础上，继续，这个时候我们须要增加一个Viewer.在这里我须要说一下，在eclipse的开发中用到的很多
的是Viewer(视图)这个概念，而不像Vb等开发中经常用到的window(窗口)，并不是说Rcp中没有窗口，而是使用
频率较低，所以分别说一下如何添加窗口和Viewer

一，添加一个对话框窗口：添加一个类如下，然後在须要显视的地方调用一下open()方法
不一定非要继承自Dialog,这里为了渐少一些代码,而且我使用中也多继承自Dialog
package hellorcp;

import org.eclipse.swt.SWT;
import org.eclipse.swt.widgets.Dialog;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Shell;

public class HelloDialog extends Dialog {

 protected Object result;

 protected Shell shell;

 public HelloDialog(Shell parent, int style) {
  super(parent, style);
 }

 public HelloDialog(Shell parent) {
  this(parent, SWT.NONE);
 }
 public Object open() {
  createContents();
  shell.open();
  shell.layout();
  Display display = getParent().getDisplay();
  while (!shell.isDisposed()) {
   if (!display.readAndDispatch())
    display.sleep();
  }
  return result;
 }

 protected void createContents() {
  shell = new Shell(getParent(), SWT.DIALOG_TRIM | SWT.APPLICATION_MODAL);
  shell.setSize(500, 375);
  shell.setText("SWT Dialog");
  //
 }

}

二，添加一个viewer，首先建立一个viewer,下边是Designer（一个很好用的插件）自动生成的一个viewer，
也就是一个Viewer的大概结构
package hellorcp;

import org.eclipse.jface.action.IMenuManager;
import org.eclipse.jface.action.IToolBarManager;
import org.eclipse.swt.SWT;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.ui.part.ViewPart;

public class HelloView extends ViewPart {

 public static final String ID = "hellorcp.HelloView"; //$NON-NLS-1$

 public void createPartControl(Composite parent) {
  Composite container = new Composite(parent, SWT.NONE);
  //
  createActions();
  initializeToolBar();
  initializeMenu();
 }

 private void createActions() {
  // Create the actions
 }
 private void initializeToolBar() {
  IToolBarManager toolbarManager = getViewSite().getActionBars()
    .getToolBarManager();
 }

 private void initializeMenu() {
  IMenuManager menuManager = getViewSite().getActionBars()
    .getMenuManager();
 }

 public void setFocus() {
  // Set the focus
 }

}
显视这个viewer,每个viewer须要加载到perspective上才能显视，所以在Perspective.java中加入如下代码
public void createInitialLayout(IPageLayout layout) {
 layout.setEditorAreaVisible(false);//不显视edit窗口
 String editorArea = layout.getEditorArea();
 //下边两句的不同是，一个显视的是单页窗口，一个显视的是多页窗口
 layout.addStandaloneView(HelloViewer.ID,false, IPageLayout.LEFT, 0.25f, editorArea);
 layout.addView(HelloViewer.ID, IPageLayout.RIGHT, 0.75f, editorArea);
｝

三，在viewer或者dialog上添加控件，如果装有Designer可以直接拖放，如果没有编程实现也可以
大部份添加到下边这样的函数中
viewer:
public void createPartControl(Composite parent) {
  Composite container = new Composite(parent, SWT.NONE);
  //添加一个button
  final Button delBtn = new Button(container, SWT.NONE);
  delBtn.setText("删除");
  delBtn.setBounds(10, 83, 44, 22);
  addListener2DelBtn(delBtn);
  
  createActions();
  initializeToolBar();
  initializeMenu();
}
dialog:
protected void createContents() {
  shell = new Shell(getParent(), SWT.DIALOG_TRIM | SWT.APPLICATION_MODAL);
  shell.setSize(500, 375);
  shell.setText("SWT Dialog");
} 

四，响应事件,SWT的事件响应和Swing是一样的，添加listener
delBtn.addSelectionListener(new SelectionAdapter() {
   public void widgetSelected(SelectionEvent e) {
    //加入你响应事件要做的事情
   }
});

五，布局
布局方面swt没有什么新的地方，发个简单使用布局的例子，参考吧.另外布局还有很多搭配，但不是本文的
重点，暂时带过
import org.eclipse.swt.SWT;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.events.SelectionListener;
import org.eclipse.swt.graphics.Font;
import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.graphics.Rectangle;
import org.eclipse.swt.layout.FormAttachment;
import org.eclipse.swt.layout.FormData;
import org.eclipse.swt.layout.FormLayout;
import org.eclipse.swt.widgets.Button;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.swt.widgets.Table;
import org.eclipse.swt.widgets.TableColumn;
import org.eclipse.swt.widgets.TableItem;

public class TableDemo {

  /**
  * @param args
  */
  public static void main(String[] args) {
    Display   dispMain = new Display ();
   
    final Shell shellMain = new Shell (dispMain, SWT.TITLE | SWT.MIN | SWT.BORDER);
       
    shellMain.setText("Table Demo");
   
    FormLayout formLayout = new FormLayout();
    formLayout.marginLeft = 10;
    formLayout.marginRight = 10;
    formLayout.marginTop = 10;
    formLayout.marginBottom = 10;
    formLayout.spacing = 10;
    shellMain.setLayout(formLayout);

    shellMain.setSize(800, 600);
    Point size = shellMain.getSize();
    Rectangle rect = dispMain.getBounds();
    shellMain.setLocation(rect.x + (rect.width-size.x)/2, rect.y + (rect.height-size.y)/2);

    Table demoTable = (Table)createContents(shellMain);    
    FormData formData = new FormData();
    formData.left = new FormAttachment(0, 0);
    formData.top = new FormAttachment(0, 0);
    formData.right = new FormAttachment(100, 0);
    formData.bottom = new FormAttachment(100, -34);
    demoTable.setLayoutData(formData);

    Button btnClose = new Button(shellMain, SWT.PUSH | SWT.FLAT);
    btnClose.setText("close");
   
    formData = new FormData();
    formData.right = new FormAttachment(100, 0);
    formData.top = new FormAttachment(demoTable, 0);
    formData.width = 100;
    formData.bottom = new FormAttachment(100, 0);
    btnClose.setLayoutData(formData);
   
    btnClose.addSelectionListener(
        new SelectionListener() {
          public void widgetDefaultSelected(SelectionEvent e) {
            this.widgetSelected(e);
          }
         
          public void widgetSelected(SelectionEvent e) {
            shellMain.close();
          }
        }
    );
    shellMain.open ();
   
    while (!shellMain.isDisposed ()) {
        if (!dispMain.readAndDispatch ()) {
          dispMain.sleep ();
        }
    }
    dispMain.dispose ();
    dispMain = null;
  }

  /**
  *
  * @param shellMain
  * @return
  */
  private static Table createContents(Shell shellMain) {
    Table table = new Table(shellMain, SWT.H_SCROLL | SWT.V_SCROLL | SWT.BORDER);
    table.setHeaderVisible(true);
    table.setLinesVisible(true);
    table.setFont(new Font(shellMain.getDisplay(), "Arial", 11, SWT.BOLD));
   
    TableColumn colNumber = new TableColumn(table, SWT.NONE);
    TableColumn colMedName = new TableColumn(table, SWT.CENTER);
    TableColumn colPrice = new TableColumn(table, SWT.CENTER);
    TableColumn colUnit = new TableColumn(table, SWT.CENTER);
    TableColumn colCount = new TableColumn(table, SWT.CENTER);
   
    colNumber.setWidth(25);
   
    colMedName.setWidth(150);
    colMedName.setText("Medicine Name");
   
    colPrice.setWidth(150);
    colPrice.setText("Medicine Price");
   
    colUnit.setWidth(150);
    colUnit.setText("Medicine Unit");
   
    colCount.setWidth(150);
    colCount.setText("Medicine Count");
   
    for(int i=0; i<10; i++) {
        TableItem item = new TableItem(table, SWT.NONE);
        item.setText(new String[]{i+1+"","4/2","4/3","4/4","4/5","4/6","4/7","4/8","4/9"});
    }
    return table;
  }
}
五，加入 右键 ，双击
加入两个listener
//右键
private void hookContextMenu() {
  MenuManager menuMgr = new MenuManager("#PopupMenu"); //$NON-NLS-1$
  menuMgr.setRemoveAllWhenShown(true);
  menuMgr.addMenuListener(new IMenuListener() {
   public void menuAboutToShow(IMenuManager manager) {
    HelloView.this.fillContextMenu(manager);
   }
  });
  Menu menu = menuMgr.createContextMenu(viewer.getControl());
  viewer.getControl().setMenu(menu);
  getSite().registerContextMenu(menuMgr, viewer);
}
private void fillContextMenu(IMenuManager manager) {
  manager.add(addAction);
  manager.add(modifyAction);
  manager.add(deleteAction);
  manager.add(new Separator(IWorkbenchActionConstants.MB_ADDITIONS));
}
//双击
private void hookDoubleClickAction() {
  viewer.addDoubleClickListener(new IDoubleClickListener() {
   public void doubleClick(DoubleClickEvent event) {
    //doubleClickAction.run();
   }
  });
}

六，使用TableViewer
Jface中封装了talbeViewer TreeViewer等控件，能简单的实现很多功能，首先说说TableView
//SWT.FULL_SELECTION 可以选中一整行
//SWT.MULTI 可以选中多行
viewer = new TableViewer(wareListGroup, SWT.BORDER | SWT.FULL_SELECTION
    | SWT.MULTI);
  final Table table = viewer.getTable();
  table.setHeaderVisible(true);//显视表头
  table.setLinesVisible(true);//显视表格
  
  //实现点击表头自动重新排序
  final TableColumn num = new TableColumn(table, SWT.NONE);
  num.addSelectionListener(new SelectionAdapter() {
   public void widgetSelected(SelectionEvent e) {
    resetSort(WareViewerSort.NUM);
    //resetSort是自己实现的重新排序的函数，只须要把不通的ViewerSort重新设置给
    TableViewer，并刷新
   }
  });
  num.setAlignment(SWT.CENTER);
  num.setWidth(50);
  //这个地方使用了message，只要做过国际话的大概都能明白
  num.setText(Messages.getString("HelloView.warenum")); //$NON-NLS-1$

  final TableColumn name = new TableColumn(table, SWT.NONE);
  name.addSelectionListener(new SelectionAdapter() {
   public void widgetSelected(SelectionEvent e) {
    resetSort(WareViewerSort.NAME);//同上
   }
  });
  name.setWidth(80);
  name.setText(Messages.getString("WareView.warename")); //$NON-NLS-1$
  name.setAlignment(SWT.CENTER);
  
  final TableColumn desc = new TableColumn(table, SWT.NONE);
  desc.addSelectionListener(new SelectionAdapter() {
   public void widgetSelected(SelectionEvent e) {
    resetSort(WareViewerSort.DESC);
   }
  });
  desc.setWidth(110);
  desc.setText(Messages.getString("WareView.waredesc")); //$NON-NLS-1$

  final TableColumn price = new TableColumn(table, SWT.NONE);
  price.addSelectionListener(new SelectionAdapter() {
   public void widgetSelected(SelectionEvent e) {
    resetSort(WareViewerSort.PRICE);
   }
  });
  price.setWidth(70);
  price.setText(Messages.getString("WareView.wareprice")); //$NON-NLS-1$
  price.setAlignment(SWT.RIGHT);

  final TableColumn updDate = new TableColumn(table, SWT.NONE);
  updDate.addSelectionListener(new SelectionAdapter() {
   public void widgetSelected(SelectionEvent e) {
    resetSort(WareViewerSort.UPDDATE);
   }
  });
  updDate.setWidth(150);
  updDate.setText(Messages.getString("WareView.wareupddate")); //$NON-NLS-1$
  updDate.setAlignment(SWT.CENTER);
  //一个TableViewer里边的数据变动主要取决于下边四句
  viewer.setContentProvider(new WareContentProvider()); //表的显视
  viewer.setLabelProvider(new WareLabelProvider());    //表的数据提供者

  viewer.setInput(//真实的数据来源); //数据来源例如ArrayList等
  viewer.setSorter(new WareViewerSort()); //排序
  
两个provider的实现类似下边的情况  
class WareContentProvider implements IStructuredContentProvider {

  public Object[] getElements(Object inputElement) {
   if (inputElement instanceof Node) {
    ArrayList list = new ArrayList();
    makeWareList(((Node) inputElement), list);
    return list.toArray();
   }
   if (inputElement instanceof List) {
    return ((List) inputElement).toArray();
   }
   return null;
  }

  public void dispose() {
   // TODO Auto-generated method stub

  }

  public void inputChanged(Viewer viewer, Object oldInput, Object newInput) {
   // TODO Auto-generated method stub

  }

 }

class WareLabelProvider extends LabelProvider implements
   ITableLabelProvider {

  public Image getColumnImage(Object element, int columnIndex) {
   // TODO Auto-generated method stub
   return null;
  }

  public String getColumnText(Object element, int columnIndex) {
   if (element instanceof Ware) {
    switch (columnIndex) {
    case 0:
     return ((Ware) element).getDisplayNum();
    case 1:
     return ((Ware) element).getDisplayName();
    case 2:
     return ((Ware) element).getDisplayDesc();
    case 3:
     return ((Ware) element).getDisplayPrice();
    case 4:
     return ((Ware) element).getDisplayUpdDate();
    default:
     break;
    }
   }
   return null;
  }

 }