SWT之ScrolledComposite

 importorg.eclipse.swt.SWT;
 importorg.eclipse.swt.custom.ScrolledComposite;
 importorg.eclipse.swt.graphics.Color;
 importorg.eclipse.swt.layout.FillLayout;
 importorg.eclipse.swt.layout.GridLayout;
 importorg.eclipse.swt.widgets.Button;
 importorg.eclipse.swt.widgets.Composite;
 importorg.eclipse.swt.widgets.Display;
 importorg.eclipse.swt.widgets.Event;
 importorg.eclipse.swt.widgets.Listener;
 importorg.eclipse.swt.widgets.Shell;
 publicclassss{
 publicstaticvoidmain(String[]args){
 Displaydisplay=newDisplay();
 Colorred=display.getSystemColor(SWT.COLOR_RED);
 Colorblue=display.getSystemColor(SWT.COLOR_BLUE);
 Shellshell=newShell(display);
 shell.setLayout(newFillLayout());
 //setthesizeofthescrolledcontent-method1
 finalScrolledCompositesc1=newScrolledComposite(shell,SWT.H_SCROLL
 |SWT.V_SCROLL|SWT.BORDER);
 finalCompositec1=newComposite(sc1,SWT.NONE);
 sc1.setContent(c1);
 c1.setBackground(red);
 GridLayoutlayout=newGridLayout();
 layout.numColumns=4;
 c1.setLayout(layout);
 Buttonb1=newButton(c1,SWT.PUSH);
 b1.setText("firstbutton");
 /*
 *这是两种用法中的一种，效果是：根据已经存在的组件，计算需要的composite的区域的大小
 *即运行结果中红色显示的部分。
 */
 c1.setSize(c1.computeSize(SWT.DEFAULT,SWT.DEFAULT));

 //settheminimumwidthandheightofthescrolledcontent-method2
 finalScrolledCompositesc2=newScrolledComposite(shell,SWT.H_SCROLL
 |SWT.V_SCROLL|SWT.BORDER);
 sc2.setExpandHorizontal(true);
 sc2.setExpandVertical(true);
 finalCompositec2=newComposite(sc2,SWT.NONE);
 sc2.setContent(c2);
 c2.setBackground(blue);
 layout=newGridLayout();
 layout.numColumns=4;
 c2.setLayout(layout);
 Buttonb2=newButton(c2,SWT.PUSH);
 b2.setText("firstbutton");
 /*
 *这是第二种用法，整个composite区域是用到的Composite区域
 */
 sc2.setMinSize(c2.computeSize(SWT.DEFAULT,SWT.DEFAULT));
 Buttonadd=newButton(shell,SWT.PUSH);
 add.setText("addchildren");
 finalint[]index=newint[]{0};
 add.addListener(SWT.Selection,newListener(){
 publicvoidhandleEvent(Evente){
 index[0]++;
 Buttonbutton=newButton(c1,SWT.PUSH);
 button.setText("button"+index[0]);
 //resetsizeofcontentsochildrencanbeseen-method1
 c1.setSize(c1.computeSize(SWT.DEFAULT,SWT.DEFAULT));
 c1.layout();
 button=newButton(c2,SWT.PUSH);
 button.setText("button"+index[0]);
 //resettheminimumwidthandheightsochildrencanbeseen-
 //method2
 sc2.setMinSize(c2.computeSize(SWT.DEFAULT,SWT.DEFAULT));
 c2.layout();
 }
 });
 shell.open();
 while(!shell.isDisposed()){
 if(!display.readAndDispatch())
 display.sleep();
 }
 display.dispose();
 }
 }