Java -- AWT ， GUI图形界面

1. AWT 容器继承关系



示例1：

public class Main {
public static void main(String[] args) throws Exception {

Frame f = new Frame();
Panel p = new Panel();    //Panel容器不能单独存在，需要添加组件，放到frame或其他容器中
p.add(new TextField(20));
p.add(new Button("clicked me"));

ScrollPane sp = new ScrollPane(ScrollPane.SCROLLBARS_ALWAYS);//ScrollPanle也不能单独存在
sp.add(p);
f.add(sp);
f.setBounds(30, 30, 300, 300);
f.setVisible(true);
}
}

2. 布局管理器： 默认的布局管理器是 BorderLayout.

FlowLayout布局： 流水一样，向某一方向顺序排列，直到边界再返回 继续顺序排列。

public class Main {

public static void main(String[] args) throws Exception {

Frame f = new Frame();
f.setLayout(new FlowLayout(FlowLayout.LEFT, 20, 5));	//Layout不采用默认构造器，左对齐，垂直水平间距为20 5
for(int i=0; i<10; i++)
{
f.add(new Button("clicked me" + i));
}

f.setBounds(30, 30, 300, 300);
f.setVisible(true);
}
}

BorderLayout ： 分为东南西北中5个区域，每个区域只能添加一个组件， 但是容器也是一种组件，所以可以先添加到一个容器里。

public class Main {

public static void main(String[] args) throws Exception {

Frame f = new Frame();
f.setLayout(new BorderLayout(20,5)); //设置5部分之间的垂直水平间隔 20 5
f.add(new Button("South"), BorderLayout.SOUTH);
f.add(new Button("North"), BorderLayout.NORTH);
f.add(new Button("West"), BorderLayout.WEST);
f.add(new Button("East"), BorderLayout.EAST);
f.add(new Button("Center"), BorderLayout.CENTER);

f.setBounds(30, 30, 300, 300);
f.setVisible(true);
}
}

GridLayout : 网格布局

public class Main {

public static void main(String[] args) throws Exception {

Frame f = new Frame();
Panel p = new Panel();
p.setLayout(new GridLayout(3, 5, 4, 4));
String [] names = {"1", "2", "3", "4", "5", "6", "7", "8", "9", "0",
"+", "-", "*", "/"};
for(int i=0; i!=names.length; i++)
{
p.add(new Button(names[i]));
}
p.add(new Button("Clicked me"), null, 14); //插入指定位置

f.add(p);
f.setBounds(30, 30, 300, 300);
f.setVisible(true);
}
}

GridBagLayout: 和GridLayout相似，不同的是一个组件可以跨越多个网格，并且可以设置网格的大小互不相同。

参考文章： GridBagLayout网格包布局管理器：http://wenku.baidu.com/link?url=hVhmI-yAsMyblLShSPOCB89ffR3Nqsur8onMDVPzgdtTOuU-13U7qhtEhFygkkWSRvooneqSdBduX-Ctj6zjPxIUVrTmWGve26MDvcCNVF3

public class Main {

private Frame f = new Frame("test GridBag");
private GridBagLayout gb = new GridBagLayout();
private GridBagConstraints gbc = new GridBagConstraints();
private Button[] bs = new Button[10];

private void init()
{
f.setLayout(gb);
for(int i=0; i<bs.length; i++)
{
bs[i] = new Button("Button" + i);
}

gbc.fill = GridBagConstraints.BOTH;
gbc.weightx = 0;  //设置缩放时的比例
gbc.weighty = 0;
addButton(bs[0]);
addButton(bs[1]);
addButton(bs[2]);
gbc.gridwidth = GridBagConstraints.REMAINDER; //设置为边界
addButton(bs[3]);

gbc.weightx = 1;
gbc.weighty = 1;
gbc.gridwidth = 1;
addButton(bs[4]);
addButton(bs[5]);
gbc.gridwidth = GridBagConstraints.REMAINDER;
addButton(bs[6]);

gbc.gridwidth = 2;   //所占网格个数
gbc.gridheight = 2;
gbc.ipadx = 50;   //组件横纵 所占像素个数
gbc.ipady = 50;
addButton(bs[7]);

gbc.gridwidth = 1;
gbc.gridheight = 1;
gbc.weighty = 0;
gbc.ipadx = 0;
gbc.ipady = 0;
addButton(bs[8]);

gbc.gridx = 4;  //组件插入到网格的坐标
gbc.gridy = 4;
addButton(bs[9]);

f.pack();
f.setVisible(true);
}

private void addButton(Button button)
{
gb.setConstraints(button, gbc);
f.add(button);
}

public static void main(String[] args) throws Exception {
new Main().init();
}
}

CardLayout: 卡片一样堆列， 每次只能看到最上面的一张。

public class Main {

private Frame f = new Frame("test CardLayout");
String [] names = {"NO1", "NO2", "NO3", "NO4", "NO5"};
Panel p1 = new Panel();
CardLayout c = new CardLayout();

public void init()
{
p1.setLayout(c);
for(int i=0; i<names.length; i++)
{
p1.add(names[i], new Button(names[i]));
}

Panel p2 = new Panel();
Button previous = new Button("Previous");
previous.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
c.previous(p1);  //前一张
}
});

Button next = new Button("Next");
next.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
c.next(p1);  //下一张
}
});

Button first = new Button("First");
first.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
c.first(p1);   //第一张
}
});

Button last = new Button("Last");
last.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
c.last(p1);  //最后一张
}
});

Button third = new Button("NO3");
third.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
c.show(p1, "NO3");  //按名字“NO3”查找
}
});

p2.add(previous);
p2.add(next);
p2.add(first);
p2.add(last);
p2.add(third);
f.add(p2);
f.add(p1, BorderLayout.NORTH);
f.pack();
f.setVisible(true);
}

public static void main(String[] args) throws Exception {
new Main().init();
}
}

2. BOX 容器

public class Main {

private Frame f = new Frame("test CardLayout");
private Box horizontal = Box.createHorizontalBox();  //水平Box容器
private Box vertical = Box.createVerticalBox();	//竖直BOX容器
public void init()
{
horizontal.add(new Button("h_Button1"));
horizontal.add(Box.createHorizontalGlue());  //添加可拉伸的水平间距
horizontal.add(new Button("h_Button2"));
horizontal.add(Box.createHorizontalStrut(50));  //添加不可拉升的水平间距，固定宽度50

vertical.add(new Button("v_Button1"));
vertical.add(Box.createVerticalGlue());   //可拉伸
vertical.add(new Button("v_Button2"));
vertical.add(Box.createVerticalStrut(50));  //固定50，不可拉伸
vertical.add(new Button("v_Button3"));

f.add(horizontal, BorderLayout.NORTH);
f.add(vertical);
f.pack();
f.setVisible(true);

}
public static void main(String[] args) throws Exception {
new Main().init();
}
}

3. 基本组件

public class Main {
public static void main(String[] args) throws Exception {

Frame f = new Frame("test CommonComponent");
Button okButton = new Button("OK");
CheckboxGroup cbg = new CheckboxGroup();
Checkbox maleCheckbox = new Checkbox("man", cbg, false);
Checkbox femaleCheckbox = new Checkbox("woman", cbg, false);
Checkbox marCheckbox = new Checkbox("married ?", false);
Choice colorChooser = new Choice();
colorChooser.add("Red");
colorChooser.add("Green");
colorChooser.add("Blue");
List colorList = new List(6, true);
colorList.add("Red");
colorList.add("Green");
colorList.add("Blue");
TextArea ta = new TextArea(5, 20);
TextField name = new TextField(50);

Panel bottom = new Panel();
bottom.add(name);
bottom.add(okButton);
Panel checkPanel = new Panel();
checkPanel.add(colorChooser);
checkPanel.add(maleCheckbox);
checkPanel.add(femaleCheckbox);
checkPanel.add(marCheckbox);

Box topLeft = Box.createVerticalBox();
topLeft.add(ta);
topLeft.add(checkPanel);
Box top = Box.createHorizontalBox();
top.add(topLeft);
top.add(colorList);

f.add(bottom, BorderLayout.SOUTH);
f.add(top);
f.pack();
f.setVisible(true);
}
}

4. Dialog 和普通窗口用法基本一样，只是可以有父控件，有两种模式“mode” "non-mode"，在“mode”下子窗口在父窗口之上，并且父窗口不能再获得焦点，构造器如下：

Dialog d1 = new Dialog(f, "mode", true);

Dialog d2 = new Dialog(f, "non-mode", false);

Dialog有子类FileDialog 用打开和保存文件。。

public class Main {
public static void main(String[] args) throws Exception {

Frame f = new Frame("test Dialog");
final FileDialog d1 = new FileDialog(f, "open file", FileDialog.LOAD);
final FileDialog d2 = new FileDialog(f, "save file", FileDialog.SAVE);
Button bt1 = new Button("open file");
Button bt2 = new Button("save file");
bt1.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
d1.setVisible(true);
System.out.println(d1.getDirectory() + d1.getFile());
}
});
bt2.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
d2.setVisible(true);
System.out.println(d1.getDirectory() + d1.getFile());
}
});

f.add(bt1);
f.add(bt2, BorderLayout.SOUTH);
f.pack();
f.setVisible(true);

}
}

5. 事件处理分类



如上表 如果直接添加WindowListener 接口那将会有右边那么多方法需要实现，所以Java会有一个WindowAdapter适配器去实现WindowListener的各个方法，但是这些方法只是空方法，User只需要继承WindowAdapter实现自己需要的方法即可。 其他Listener也有其对应的Adapter.