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在JAVA语言中,下面是main()方法的部分代码: JFrame f=new JFrame(“My Frame”); f.setSize(100,100); 为在屏幕显示f,应增加的代码是()。
A.f.appear();
B.f.setForeground();
C.f.setVisible(true);
D.f.enable();
参考答案和解析
BD
更多 “在JAVA语言中,下面是main()方法的部分代码: JFrame f=new JFrame(“My Frame”); f.setSize(100,100); 为在屏幕显示f,应增加的代码是()。A.f.appear();B.f.setForeground();C.f.setVisible(true);D.f.enable();” 相关考题
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在Java语言中,下面是main()方法的部分代码:Framef=newFrame(MyFrame);f.setSize(100,100);为在屏幕显示f,应增加的代码是()。
A.f.appear();B.f.setForeground();C.f.setVisible();D.f.enable();
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每个Java小应用程序必须定义为( )。 A.Applet类或JApplet类的子类B.JFrame类的子类S
每个Java小应用程序必须定义为( )。A.Applet类或JApplet类的子类B.JFrame类的子类C.Frame的子类D.Window的子类
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● 以下是某网页框架设置的部分代码,该代码将页面分成了 (61)个区域。frameset cols="30%,*,*"frame. src='f1.html" name=main……frameset rows="120,*"frame. src='f2.html" name=left……/frameset/frameset(61)A. 2B. 3C. 4D. 5
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以下是某网页框架设置的部分代码,该代码将页面分成了______个区域。<frameset cols="30%,*,*"><frame src='f1.html"name=main><frameset rows="120,*"><frame src='f2.html"name=left>…</frameset></frameset>A.2
B.3
C.4
D.5
考题
在Java语言中,下面是main()方法的部分代码: Frame f = new Frame("My Frame"); f.setSize(100,100); 为在屏幕显示f,应增加的代码是()。 A、f.appear();B、f.setForeground();C、f.setVisible();D、f.enable();
考题
单选题下列关于程序运行结果的描述中,错误的是( )。import javax.swing.*; import java.awt.*; public class Test{ public static void main(String[]args){ JFrame f = new JFrame(); JPanel P=new JPanel(); f.setLayout(new BorderLayout()); f.getContentPane().add(p,"Center"); P.setBackground(Color.blue); f.setVisible(true); f.setSize(200,200); } }A
程序不能运行B
显示一个窗口C
窗口大小是200×200D
窗口背景为蓝色
考题
单选题现有: package mypack; import javax.swing.JButton; import javax.swing.JFrame; public class Butt extends JFrame { public static v.id main(string[] args) { // TODO Auto-generated method stub Butt butt=new Butt(); } Butt(){ JButton jbl=new JButton("Hello"); JButton jb2=new JButton("World"); add(jbl); add(jb2); setSize(300,300); setVisible(true); } } 下列关于代码运行效果的叙述正确的是哪项? ()A
2个按钮紧靠着排列,Hello在World的左侧B
Hello占据Frame的整个区域C
World占据Frame的整个区域D
2个按钮都在Frame的顶部
考题
单选题在Java语言中,下面是main()方法的部分代码: Frame f = new Frame("My Frame"); f.setSize(100,100); 为在屏幕显示f,应增加的代码是()。A
f.appear();B
f.setForeground();C
f.setVisible();D
f.enable();
考题
单选题现有: package mypack; import java.awt.Color; import java.awt.FlowLayout; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JPanel; public class ButtList extends JFrame { public static void main(String[] args) { ButtList bl =new ButtList(); } ButtList(){ JPanel pl=new JPanel(); pl.setBackground (Color.pink); p1.add(new JButton("one")); p1.add(new JButton("Two")); p1.add(new JButton("Three")); add("South",p1); setLayout(new Fl.wLayout()); setSize(200,200); setVisible(true); } } 上述代码运行后的显示效果是哪项?()A
3个按钮从左到右排列在Frame的底部B
3个按钮从左到右排列在Frame的顶部C
按钮无法显示D
只有按钮Three显示出来并占据Frame整个区域
考题
单选题JFrame中的哪个方法用来将它显示在屏幕上()。A
setResizableB
setVisibleC
isVisibleD
setForeground
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