java JTextField 只显示为一个狭缝 使用 GridBagLayout，需要帮助
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JTextField only shows as a slit Using GridBagLayout, need help
提问by Bill.Caffery
Hi thank you in advance for any help, I'm trying to build a simple program to learn GUI's but when I run the code below my JTextFields all show as a slit thats not large enough for even one character.
嗨，提前感谢您的任何帮助，我正在尝试构建一个简单的程序来学习 GUI，但是当我运行 JTextFields 下面的代码时，所有代码都显示为一个狭缝，甚至一个字符都不够大。
cant post an image but it would look similar to: Label [|
无法发布图像，但它看起来类似于：标签 [|
where [| is what the text field actually looks like
其中 [| 是文本字段的实际外观
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.*;
public class lab6start implements ActionListener
{
JTextField custNameTxt;
JTextField acctNumTxt;
JTextField dateCreatedTxt;
JButton checkingBtn;
JButton savingsBtn;
JTextField witAmountTxt;
JButton withDrawBtn;
JTextField depAmountTxt;
JButton depositBtn;
lab6start()
{
JFrame bankTeller = new JFrame("Welcome to Suchnsuch Bank");
bankTeller.setSize(500, 280);
bankTeller.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
bankTeller.setResizable(false);
bankTeller.setLayout(new GridBagLayout());
bankTeller.setBackground(Color.gray);
//bankTeller.getContentPane().add(everything, BorderLayout.CENTER);
GridBagConstraints c = new GridBagConstraints();
JPanel acctInfo = new JPanel(new GridBagLayout());
c.gridx = 0;
c.gridy = 0;
c.gridwidth = 2;
c.gridheight = 1;
c.insets = new Insets(5,5,5,5);
bankTeller.add(acctInfo, c);
c.gridwidth = 1;
//labels
//name acct# balance interestRate dateCreated
JLabel custNameLbl = new JLabel("Name");
c.gridx = 0;
c.gridy = 0;
c.insets = new Insets(0,0,0,0);
acctInfo.add(custNameLbl, c);
custNameTxt = new JTextField("customer name",50);
c.gridx = 1;
c.gridy = 0;
c.insets = new Insets(5,5,5,5);
acctInfo.add(custNameTxt,c);
custNameTxt.requestFocusInWindow();
JLabel acctNumLbl = new JLabel("Account Number");
c.gridx = 0;
c.gridy = 1;
c.insets = new Insets(5,5,5,5);
acctInfo.add(acctNumLbl,c);
acctNumTxt = new JTextField("account number");
c.gridx = 1;
c.gridy = 1;
c.insets = new Insets(5,5,5,5);
acctInfo.add(acctNumTxt,c);
JLabel dateCreatedLbl = new JLabel("Date Created");
c.gridx = 0;
c.gridy = 2;
c.insets = new Insets(5,5,5,5);
acctInfo.add(dateCreatedLbl,c);
dateCreatedTxt = new JTextField("date created");
c.gridx = 1;
c.gridy = 2;
c.insets = new Insets(5,5,5,5);
acctInfo.add(dateCreatedTxt,c);
//buttons
checkingBtn = new JButton("Checking");
c.gridx = 0;
c.gridy = 3;
c.insets = new Insets(5,5,5,5);
acctInfo.add(checkingBtn,c);
savingsBtn = new JButton("Savings");
c.gridx = 1;
c.gridy = 3;
c.insets = new Insets(5,5,5,5);
acctInfo.add(savingsBtn,c);
//end of info panel
JPanel withDraw = new JPanel(new GridBagLayout());
c.gridx = 0;
c.gridy = 1;
c.insets = new Insets(5,5,5,5);
bankTeller.add(withDraw, c);
witAmountTxt = new JTextField("Amount to Withdraw:");
c.gridx = 0;
c.gridy = 0;
c.insets = new Insets(5,5,5,5);
withDraw.add(witAmountTxt,c);
withDrawBtn = new JButton("Withdraw");
c.gridx = 1;
c.gridy = 0;
c.insets = new Insets(5,5,5,5);
withDraw.add(withDrawBtn,c);
//add check balance
//end of withdraw panel
JPanel deposit = new JPanel(new GridBagLayout());
c.gridx = 1;
c.gridy = 1;
c.insets = new Insets(5,5,5,5);
bankTeller.add(deposit, c);
depAmountTxt = new JTextField("Amount to Deposit");
c.gridx = 0;
c.gridy = 0;
c.insets = new Insets(5,5,5,5);
deposit.add(depAmountTxt,c);
depositBtn = new JButton("Deposit");
c.gridx = 1;
c.gridy = 0;
c.insets = new Insets(5,5,5,5);
deposit.add(depositBtn,c);
bankTeller.setVisible(true);
// action/event
checkingBtn.addActionListener(this);
savingsBtn.addActionListener(this);
withDrawBtn.addActionListener(this);
depositBtn.addActionListener(this);
}
public void actionPerformed(ActionEvent e)
{
if (e.getSource()== checkingBtn)
{
witAmountTxt.requestFocusInWindow();
//checking newcheck = new checking();
}
}
}
/*
String accountType = null;
accountType = JOptionPane.showInputDialog(null, "Checking or Savings?");
if (accountType.equalsIgnoreCase("checking"))
{
checking c_Account = new checking();
}
else if (accountType.equalsIgnoreCase("savings"))
{
// savings s_Account = new savings();
}
else
{
JOptionPane.showMessageDialog(null, "Invalid Selection");
}
*/
采纳答案by Hovercraft Full Of Eels
Try calling pack() on your JFrame after adding everything and before setVisible(true)
在添加所有内容之后和 setVisible(true) 之前尝试在 JFrame 上调用 pack()
Also, you'll not want to forget to set the GridBagConstraints weightx and weighty fields. At least give them a non-0 value such as 1.0 for most fields and 0 for fields whose size you don't want changed if the GUI changes size.
此外，您不会忘记设置 GridBagConstraints weightx 和 weighty 字段。至少给它们一个非 0 值，例如大多数字段的 1.0 和 0 字段的大小，如果 GUI 更改大小，则不希望更改其大小。
回答by Stepan Yakovenko
Adding those works for me:
为我添加这些作品：
c.weightx=1.;
c.fill=GridBagConstraints.HORIZONTAL;
回答by Spike Williams
There is also a bug in Swing that could result in a JTextArea showing up as a slit, although Sun/Oracle says "its not a bug, its a feature":
Swing 中还有一个错误，它可能导致 JTextArea 显示为一个狭缝，尽管 Sun/Oracle 说“这不是错误，而是一个特性”：
http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4247013
http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4247013
One potential solution that someone suggested on that thread is to set the minimum size of the JTextField... something like this:
有人在该线程上建议的一种可能的解决方案是设置 JTextField 的最小大小......像这样：
textField.setMinimumSize(textField.getPreferredSize());
回答by peter.murray.rust
I'm guessing from the name lab6 that you may not have used GridBagLayout before. It is one of the most difficult and feared of the Swing Layout tools. If you haven't used it I'd suggest working through tutorials such as: http://download.oracle.com/javase/tutorial/uiswing/layout/gridbag.htmland building up to your example
我从名称 lab6 猜测您之前可能没有使用过 GridBagLayout。它是 Swing Layout 工具中最困难和最令人恐惧的工具之一。如果您还没有使用过它，我建议您学习以下教程：http: //download.oracle.com/javase/tutorial/uiswing/layout/gridbag.html并构建您的示例
