JFrame和JPanel问题 [英] JFrame and JPanel problems
问题描述
我正在尝试为一家当地的百吉饼商店制作程序，该商店出售糕点，百吉饼和咖啡.我在实现我在JFrame中制作的面板时遇到了麻烦
I am attempting to make a program for a local bagel shop that sells pastries, bagels, and coffee. I am having trouble implementing the panels that I have made into the JFrame
了解如何使我的JFrame看起来像这样的任何帮助都会很有帮助 http://kepler.covenant.edu/COS150/Bagel_files/image002.jpg
any help understanding how to make my JFrame look like this would be helpful http://kepler.covenant.edu/COS150/Bagel_files/image002.jpg
一旦完成这项工作，我希望中间的面板组根据所选的产品而有所不同.我不完全确定如何使按钮和面板彼此对话.
Once I have this working I hope to have the middle set of panels change depending on which product is selected. I am not entirely sure how to make the buttons and panels talk to one another.
感谢帮助！
这是到目前为止我的JFrame代码.
here is my code for the JFrame so far.
import java.awt.BorderLayout;
import javax.swing.JFrame;
import javax.swing.JLabel;
public class BagelOrder extends JFrame
{
JLabel topLabel;
sizePanel sp = new sizePanel();
typePanel tp = new typePanel();
productsPanel pp = new productsPanel();
buttonPanel bp = new buttonPanel();
extrasPanel ep = new extrasPanel();
public BagelOrder()
{
setTitle("Order Entry Screen");
setSize(800, 800);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
topLabel = new JLabel("Order Entry Screen");
add(pp, BorderLayout.WEST);
add(topLabel, BorderLayout.NORTH);
add(bp, BorderLayout.SOUTH);
add(middleCoffeePanelSetBuild(), BorderLayout.CENTER);
add(east, BorderLayout.EAST);
setVisible(true);
}
private JPanel middleCoffeePanelSetBuild()
{
JPanel middlePanel = new JPanel(new GridLayout(3,1));
add(sp);
add(tp);
add(ep);
}
public static void main(String args[])
{
BagelOrder bo = new BagelOrder();
}
}
我没有任何错误，但是除了页面顶部的标签外，我看不到其他任何东西.
I have no errors but I cannot see anything other than the label at the top of the page.
这是我其他班级的代码
ButtonPanel
ButtonPanel
import java.awt.GridLayout;
import javax.swing.ButtonGroup;
import javax.swing.JButton;
import javax.swing.JPanel;
public class buttonPanel extends JPanel
{
JButton enterItemButton;
JPanel buttonPanel;
ButtonGroup bg;
JButton totalButton;
JButton newOrderButton;
public buttonPanel()
{
buttonPanel = new JPanel(new GridLayout(1,3));
bg = new ButtonGroup();
enterItemButton = new JButton("Enter Item");
totalButton = new JButton("Total");
newOrderButton = new JButton("New Order");
buttonPanel.setSize(150, 780);
buttonPanel.add(enterItemButton);
bg.add(enterItemButton);
buttonPanel.add(totalButton);
bg.add(totalButton);
buttonPanel.add(newOrderButton);
bg.add(newOrderButton);
setVisible(true);
}
}
ProductPanel
ProductPanel
import java.awt.GridLayout;
import javax.swing.BorderFactory;
import javax.swing.ButtonGroup;
import javax.swing.JPanel;
import javax.swing.JRadioButton;
import javax.swing.border.Border;
public class productsPanel extends JPanel
{
public productsPanel()
{
JPanel productPanel = new JPanel(new GridLayout(3,1));
ButtonGroup bg = new ButtonGroup();
JRadioButton coffeeButton = new JRadioButton("Coffee");
JRadioButton bagelButton = new JRadioButton("Bagel");
JRadioButton pastryButton = new JRadioButton("Pastry");
productPanel.setSize(150, 780);
productPanel.add(coffeeButton);
bg.add(coffeeButton);
productPanel.add(bagelButton);
bg.add(bagelButton);
productPanel.add(pastryButton);
bg.add(pastryButton);
Border etched = BorderFactory.createEtchedBorder();
Border titled = BorderFactory.createTitledBorder(etched, "Products");
productPanel.setBorder(titled);
setVisible(true);
}
}
尺寸面板
import java.awt.GridLayout;
import javax.swing.BorderFactory;
import javax.swing.ButtonGroup;
import javax.swing.JPanel;
import javax.swing.JRadioButton;
import javax.swing.border.Border;
public class sizePanel extends JPanel{
public sizePanel()
{
JPanel sp = new JPanel(new GridLayout(3,1));
ButtonGroup bg = new ButtonGroup();
JRadioButton smallButton = new JRadioButton("Small");
JRadioButton mediumButton = new JRadioButton("Medium");
JRadioButton largeButton = new JRadioButton("Large");
sp.setSize(200, 200);
sp.add(smallButton);
bg.add(smallButton);
sp.add(mediumButton);
bg.add(mediumButton);
sp.add(largeButton);
bg.add(largeButton);
Border etched = BorderFactory.createEtchedBorder();
Border titled = BorderFactory.createTitledBorder(etched, "Size");
sp.setBorder(titled);
setVisible(true);
}
}
TypePanel
TypePanel
import java.awt.GridLayout;
import javax.swing.BorderFactory;
import javax.swing.ButtonGroup;
import javax.swing.JPanel;
import javax.swing.JRadioButton;
import javax.swing.border.Border;
public class typePanel extends JPanel
{
public typePanel()
{
JPanel typePanel = new JPanel(new GridLayout(3,1));
ButtonGroup bg = new ButtonGroup();
JRadioButton regularButton = new JRadioButton("Regular");
JRadioButton decafButton = new JRadioButton("Decaf");
JRadioButton frenchRoastButton = new JRadioButton("French Roast");
typePanel.setSize(200, 200);
typePanel.add(regularButton);
bg.add(regularButton);
typePanel.add(decafButton);
bg.add(decafButton);
typePanel.add(frenchRoastButton);
bg.add(frenchRoastButton);
Border etched = BorderFactory.createEtchedBorder();
Border titled = BorderFactory.createTitledBorder(etched, "Type");
typePanel.setBorder(titled);
setVisible(true);
}
}
ExtrasPanel
ExtrasPanel
import java.awt.GridLayout;
import javax.swing.BorderFactory;
import javax.swing.JCheckBox;
import javax.swing.JPanel;
import javax.swing.border.Border;
public class extrasPanel extends JPanel
{
public extrasPanel()
{
JPanel extrasPanel = new JPanel(new GridLayout(2,1));
JCheckBox creamCheckBox = new JCheckBox("Cream");
JCheckBox sugarCheckBox = new JCheckBox("Sugar");
extrasPanel.setSize(200, 200);
extrasPanel.add(creamCheckBox);
extrasPanel.add(sugarCheckBox);
Border etched = BorderFactory.createEtchedBorder();
Border titled = BorderFactory.createTitledBorder(etched, "Extras");
extrasPanel.setBorder(titled);
setVisible(true);
}
}
推荐答案
编写Swing GUI时应注意的一些好的做法:
Some good practices to get into when writing Swing GUI's:
1)您的Panel类构建错误. 您需要重新编写buttonPanel以及所有其他代码，以便它们显示为:
1) Your Panel classes are built wrong. You need to re-write buttonPanel, and all of your others, so that they read like this:
public buttonPanel() {
super(new GridLayout(1,3));
bg = new ButtonGroup();
enterItemButton = new JButton("Enter Item");
totalButton = new JButton("Total");
newOrderButton = new JButton("New Order");
this.setSize(150, 780);
this.add(enterItemButton);
bg.add(enterItemButton);
this.add(totalButton);
bg.add(totalButton);
this.add(newOrderButton);
bg.add(newOrderButton);
this.setVisible(true);
}
}
您当前编写的方式是，您有一个ButtonPanel类(始终为大写类)，该类拥有一个带有按钮的JPanel，但它永远不会显示其拥有的JPanel.您需要ButtonPanel成为JPanel，而不仅仅是拥有一个. 多数民众赞成在主要问题.您可以改善的次要点:
The way yours is currently written, you have a ButtonPanel class (always capitalise classes) which posseses a JPanel with the buttons on it, but it never displays this JPanel that it owns. You need ButtonPanel to BE a JPanel, not just own one. Thats the major issue. Minor points you could improve on:
2)JFrame具有一个名为contentPane的JPanel.正如jzd所说，当使用JFrame.add时，您实际上是在调用JFrame.getContentPane.add(Component c).这是一种方便的方法，但是它隐藏了您的实际操作.尤其是在学习时，捷径是不好的.
2) The JFrame has a JPanel called the contentPane. As said by jzd, when using JFrame.add you are really calling JFrame.getContentPane.add(Component c). This is a convenience method, but it hides what you are really doing. Especially when you're just learning, shortcuts are bad.
我个人走得更远，开始我的JFrames
I personally go a step further, starting my JFrames off with
JPanel content = new JPanel(new BorderLayout());
content.add(...);
....
this.setContentPane(content);
3)扩展类(如JFrame)从对super()的调用开始时是一个好习惯.再次，您可以将它省略为速记，但在开始时花一点时间学习它是有益的.这将调用超类的构造函数(带有您需要的任何参数)，基本上是说让我们创建基本的JFrame，然后对其应用扩展".
3) It is good practice when extending a class (like JFrame) to begin with a call to super(). Again, you can leave it out as shorthand, but its good to be pedantic when beginning. This calls the superclass's constructor (with whatever arguments you need), which is basically saying "Lets create the basic JFrame, and then apply my extensions to it".
4)同样好的做法是大写您的类，并以小写动词开头所有功能.即ButtonPanel或build()
4) Its also good practice to capitalise your classes, and begin all functions with lowercase verbs. ie ButtonPanel or build()
5)似乎您只是刚刚开始使用GUI，但我可能会建议使用外部库"MigLayout"(使用Google).令人惊讶的是，它的强大功能和便捷性使您不必为所有Java内置的，可怕的布局类型而苦恼.
5) It seems like you're only just starting out with GUI, but might I recommend the external library "MigLayout" (google it). Its amazing in the extra power and ease that it gives you over struggling against all of Java's inbuilt, horrible, layout types.
这篇关于JFrame和JPanel问题的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
