当我动态创建文本和标签框时,它应该采用“文本框:标签框”的格式,然后当我再次单击添加按钮时,相同的模式应该在下一行重复,依此类推...我应该使用哪种布局使用以及如何使用?
这是我使用的代码
if(field_name.getText().equals("")){
error.setForeground(Color.red);
error.setText("Enter the Field name first");
} else {
JLabel l = new JLabel(field_name.getText(), JLabel.RIGHT);
JTextField textField = new JTextField();
Dimension dim = new Dimension(20,30);
textField.setPreferredSize(dim);
field_layer.add(l);
field_layer.add(textField);
SpringUtilities.makeCompactGrid(field_layer,
numPairs, 2, //rows, cols
6, 6, //initX, initY
6, 6); //xPad, yPad
numPairs++;
field_layer.invalidate();
this.pack();
}
最佳答案
一个选项是 GridBagLayout .为了正确使用此布局,您需要了解 GridBagConstraints .这是一个 tutorial帮助您入门。
这是一个简单的例子:
import java.awt.Dimension;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.ArrayList;
import java.util.List;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.border.LineBorder;
public class MyExample
{
// Field members
static JPanel panel = new JPanel();
static Integer indexer = 1;
static List<JLabel> listOfLabels = new ArrayList<JLabel>();
static List<JTextField> listOfTextFields = new ArrayList<JTextField>();
public static void main(String[] args)
{
// Construct frame
JFrame frame = new JFrame();
frame.setLayout(new GridBagLayout());
frame.setPreferredSize(new Dimension(300, 300));
frame.setTitle("My Example");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
// Frame constraints
GridBagConstraints frameConstraints = new GridBagConstraints();
// Construct button
JButton addButton = new JButton("Add");
addButton.addActionListener(new ButtonListener());
// Add button to frame
frameConstraints.gridx = 0;
frameConstraints.gridy = 0;
frame.add(addButton, frameConstraints);
// Construct panel
panel.setPreferredSize(new Dimension(200, 200));
panel.setLayout(new GridBagLayout());
panel.setBorder(LineBorder.createBlackLineBorder());
// Add panel to frame
frameConstraints.gridx = 0;
frameConstraints.gridy = 1;
frameConstraints.weighty = 1;
frame.add(panel, frameConstraints);
// Pack frame
frame.pack();
// Make frame visible
frame.setVisible(true);
}
static class ButtonListener implements ActionListener
{
@Override
public void actionPerformed(ActionEvent arg0)
{
// Clear panel
panel.removeAll();
// Create label and text field
listOfTextFields.add(new JTextField());
listOfLabels.add(new JLabel("Label " + indexer));
// Create constraints
GridBagConstraints textFieldConstraints = new GridBagConstraints();
GridBagConstraints labelConstraints = new GridBagConstraints();
// Add labels and text fields
for(int i = 0; i < indexer; i++)
{
// Text field constraints
textFieldConstraints.gridx = 0;
textFieldConstraints.gridy = i;
// Label constraints
labelConstraints.gridx = 1;
labelConstraints.gridy = i;
// Add them to panel
panel.add(listOfTextFields.get(i), textFieldConstraints);
panel.add(listOfLabels.get(i), labelConstraints);
}
// Align components top-to-bottom
GridBagConstraints c = new GridBagConstraints();
c.gridx = 0;
c.gridy = indexer;
c.weighty = 1;
panel.add(new JLabel(), c);
// Increment indexer
indexer++;
}
}
}
注意:不要将自己局限于这个特定的布局管理器。也就是说,您应该探索其他 Layout Managers也是。
关于java - 我想通过单击添加按钮动态添加 JLabel 和文本框,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/5098017/