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();
}
}