Java 如何将数据插入JTable?
我编写此代码用于在表中显示字符串 但它没有显示出来,也没有效果 什么是问题Java 如何将数据插入JTable?,java,swing,jtable,Java,Swing,Jtable,我编写此代码用于在表中显示字符串 但它没有显示出来,也没有效果 什么是问题 public pamnel() { initComponents(); String[] columnNames = {"First Name", "Last Name", "Sport", "# of
public pamnel() {
initComponents();
String[] columnNames = {"First Name",
"Last Name",
"Sport",
"# of Years",
"Vegetarian"};
Object[][] data = {
{"Kathy", "Smith",
"Snowboarding", new Integer(5), new Boolean(false)},
{"John", "Doe",
"Rowing", new Integer(3), new Boolean(true)},
{"Sue", "Black",
"Knitting", new Integer(2), new Boolean(false)},
{"Jane", "White",
"Speed reading", new Integer(20), new Boolean(true)},
{"Joe", "Brown",
"Pool", new Integer(10), new Boolean(false)}
};
jTable1 = new JTable(data, columnNames);
}
编辑:
我在面板上添加Jtable
在主面板中,将添加到jframe
JFrame frame = new JFrame();
frame.add(new pamnel());
frame.setVisible(true);
frame.setSize(600, 600);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
该表已显示,但未显示数据。
表的行和列为空 您必须将JTable添加到其父组件和setVisible()。您必须将JTable添加到其父组件和setVisible()。您真的是自己编写代码的吗?我记得这是一个oracle swing教程。无论如何,您还没有将
JTable
添加到组件中。观察下面
封装组件;
/*
*SimpleTableDemo.java不需要其他文件。
*/
导入javax.swing.JFrame;
导入javax.swing.JPanel;
导入javax.swing.JScrollPane;
导入javax.swing.JTable;
导入java.awt.Dimension;
导入java.awt.GridLayout;
导入java.awt.event.MouseAdapter;
导入java.awt.event.MouseEvent;
公共类SimpleTableDemo扩展了JPanel{
私有布尔调试=false;
公共SimpleTableDemo(){
超级(新网格布局(1,0));
String[]columnNames={“名字”,
“姓氏”,
“运动”,
“#年”,
“素食者”};
对象[][]数据={
{“凯西”,“史密斯”,
“滑雪板”,新整数(5),新布尔值(假)},
{“约翰”,“多伊”,
“划船”,新整数(3),新布尔值(真)},
{“苏”,“黑”,
“编织”,新整数(2),新布尔值(假)},
{“简”、“白”,
“快速读取”,新整数(20),新布尔值(真)},
{“乔”,“布朗”,
“Pool”、新整数(10)、新布尔值(false)}
};
最终JTable表=新JTable(数据、列名称);
表.setPreferredScrollableViewportSize(新维度(500,70));
表.setFillsViewPerthweight(真);
如果(调试){
表.addMouseListener(新的MouseAdapter(){
公共无效mouseClicked(MouseEvent e){
打印数据(表格);
}
});
}
//创建滚动窗格并将表添加到其中。
JScrollPane scrollPane=新的JScrollPane(表);
//将滚动窗格添加到此面板。
添加(滚动窗格);
}
私有无效printDebugData(JTable表){
int numRows=table.getRowCount();
int numCols=table.getColumnCount();
javax.swing.table.TableModel=table.getModel();
System.out.println(“数据值:”);
对于(int i=0;i
JTable被添加到
SimpleTableDemo
构造函数中的JPanel中。然后将JPanel设置为主JFrame的中的内容窗格,其设置为frame.setVisible(true)。这在createAndShowGUI
方法中发生。代码不显示JTable的原因是JTable是一个抽象的小部件。您需要将抽象小部件添加到组件中,例如JFrame(在上述情况下)才能显示它。您真的是自己编写代码的吗?我记得这是一个oracle swing教程。无论如何,您还没有将JTable
添加到组件中。观察下面
封装组件;
/*
*SimpleTableDemo.java不需要其他文件。
*/
导入javax.swing.JFrame;
导入javax.swing.JPanel;
导入javax.swing.JScrollPane;
导入javax.swing.JTable;
导入java.awt.Dimension;
导入java.awt.GridLayout;
导入java.awt.event.MouseAdapter;
导入java.awt.event.MouseEvent;
公共类SimpleTableDemo扩展了JPanel{
私有布尔调试=false;
公共SimpleTableDemo(){
超级(新网格布局(1,0));
String[]columnNames={“名字”,
“姓氏”,
“运动”,
“#年”,
“素食者”};
对象[][]数据={
{“凯西”,“史密斯”,
“滑雪板”,新整数(5),新布尔值(假)},
{“约翰”,“多伊”,
“划船”,新整数(3),新布尔值(真)},
{“苏”,“黑”,
“编织”,新整数(2),新布尔值(假)},
{“简”、“白”,
“快速读取”,新整数(20),新布尔值(真)},
{“乔”,“布朗”,
“Pool”、新整数(10)、新布尔值(false)}
};
最终JTable表=新JTable(数据、列名称);
表.setPreferredScrollableViewportSize(新维度(500,70));
表.setFillsViewPerthweight(真);
如果(调试){
表.addMouseListener(新Mou)
package components;
/*
* SimpleTableDemo.java requires no other files.
*/
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import java.awt.Dimension;
import java.awt.GridLayout;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
public class SimpleTableDemo extends JPanel {
private boolean DEBUG = false;
public SimpleTableDemo() {
super(new GridLayout(1,0));
String[] columnNames = {"First Name",
"Last Name",
"Sport",
"# of Years",
"Vegetarian"};
Object[][] data = {
{"Kathy", "Smith",
"Snowboarding", new Integer(5), new Boolean(false)},
{"John", "Doe",
"Rowing", new Integer(3), new Boolean(true)},
{"Sue", "Black",
"Knitting", new Integer(2), new Boolean(false)},
{"Jane", "White",
"Speed reading", new Integer(20), new Boolean(true)},
{"Joe", "Brown",
"Pool", new Integer(10), new Boolean(false)}
};
final JTable table = new JTable(data, columnNames);
table.setPreferredScrollableViewportSize(new Dimension(500, 70));
table.setFillsViewportHeight(true);
if (DEBUG) {
table.addMouseListener(new MouseAdapter() {
public void mouseClicked(MouseEvent e) {
printDebugData(table);
}
});
}
//Create the scroll pane and add the table to it.
JScrollPane scrollPane = new JScrollPane(table);
//Add the scroll pane to this panel.
add(scrollPane);
}
private void printDebugData(JTable table) {
int numRows = table.getRowCount();
int numCols = table.getColumnCount();
javax.swing.table.TableModel model = table.getModel();
System.out.println("Value of data: ");
for (int i=0; i < numRows; i++) {
System.out.print(" row " + i + ":");
for (int j=0; j < numCols; j++) {
System.out.print(" " + model.getValueAt(i, j));
}
System.out.println();
}
System.out.println("--------------------------");
}
/**
* Create the GUI and show it. For thread safety,
* this method should be invoked from the
* event-dispatching thread.
*/
private static void createAndShowGUI() {
//Create and set up the window.
JFrame frame = new JFrame("SimpleTableDemo");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//Create and set up the content pane.
SimpleTableDemo newContentPane = new SimpleTableDemo();
newContentPane.setOpaque(true); //content panes must be opaque
frame.setContentPane(newContentPane);
//Display the window.
frame.pack();
frame.setVisible(true);
}
public static void main(String[] args) {
//Schedule a job for the event-dispatching thread:
//creating and showing this application's GUI.
javax.swing.SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGUI();
}
});
}
}
import javax.swing.*;
class TableDemo {
JTable jTable1;
public static void main( String ... args ) {
TableDemo tableDemo = new TableDemo();
tableDemo.pamnel();
JFrame frame = new JFrame();
frame.add( new JScrollPane(tableDemo.jTable1) );
frame.pack();
frame.setVisible( true );
}
public void initComponents(){
}
public void pamnel() {
initComponents();
String[] columnNames = {"First Name",
"Last Name",
"Sport",
"# of Years",
"Vegetarian"};
Object[][] data = {
{"Kathy", "Smith",
"Snowboarding", new Integer(5), new Boolean(false)},
{"John", "Doe",
"Rowing", new Integer(3), new Boolean(true)},
{"Sue", "Black",
"Knitting", new Integer(2), new Boolean(false)},
{"Jane", "White",
"Speed reading", new Integer(20), new Boolean(true)},
{"Joe", "Brown",
"Pool", new Integer(10), new Boolean(false)}
};
jTable1 = new JTable(data, columnNames);
}
}
private JTable jTable1 = new JTable(); // empty table
public pamnel() {
initComponents();
String[] columnNames = ...
Object[][] data = ...
jTable1 = new JTable(data, columnNames); // new instance created here
// nothing happens with that new instance
}
private void initComponents() {
...
add(jTable1); // added empty table, not the one created above (constructor)
...
}
private JTable jTable1;
public pamnel() {
initComponents();
}
private void initComponents() {
...
createTable();
add(jTable1);
...
}
private void createTable() {
String[] columnNames = ...
Object[][] data = ...
jTable1 = new JTable(data, columnNames);
}