我需要帮助的人。我有一个页面/框架显示第一个面板。第一个面板，它将按钮与数据库中的图像。单击按钮时，将删除第一个面板并显示第二个面板。第二个面板显示数据库中的图像及其描述。问题是我想在第二个面板上显示一个特定的图像及其描述。这是我的代码。我希望你能帮助我。这是我的代码，随时可以测试它。
头等舱：
package state_switcher;
/**
* @author Ron Brash (ron.brash@gmail.com)
*
* The concept of this enum is to contain the states
* to render the correct button/panels.
*/
public enum ViewState {
START_STATE, NEXT_STATE;
}
第二课：
package state_switcher;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.image.BufferedImage;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import state_switcher.ViewState;
/**
* @author Ron Brash (ron.brash@gmail.com)
*
* The concept of this class is to create a panel which
* contains a JButton which has an inline actionListener.
*
* The action listener will change the state using a static
* function from the class Main.
*/
@SuppressWarnings("serial")
public class Panel1 extends JPanel {
static int xy;
public Panel1() {
JPanel panel1 = new JPanel();
String url = "jdbc:mysql://localhost:3306/";
String user = "root";
String pass = "";
try
{
Class.forName("com.mysql.jdbc.Driver").newInstance();
Connection con = DriverManager.getConnection(url, user, pass);
Statement stt = con.createStatement();
//Get people with surname
ResultSet res = stt.executeQuery("SELECT * FROM products");
setLayout(null);
int i = 1, x = 10, y = 1, z = 10;
while(res.next())
{
String val = Integer.toString(i);
String fileName = "D:\\" + res.getString("image");
ImageIcon imageIcon = new ImageIcon(fileName);
JButton btn = new JButton(resize(imageIcon, 100, 200));
btn.setName(val);
btn.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
// display the second panel when pressed.
Main.changeState(ViewState.NEXT_STATE);
}
}); //add an actionListener right away
if(y <= 3)
{
add(btn).setBounds(x, z, 100, 200);
}
else
{
y = 1;
x = 10;
z += 220;
add(btn).setBounds(x, z, 100, 200);
}
x+=130;
y++;
i++;
}
//Free resources
res.close();
stt.close();
con.close();
}
catch(Exception e)
{
e.printStackTrace();
}
this.add(panel1);
}
public static ImageIcon resize(ImageIcon imageIcon, int width, int height)
{
BufferedImage bi = new BufferedImage(width, height, BufferedImage.TRANSLUCENT);
Graphics2D g2d = (Graphics2D) bi.createGraphics();
g2d.addRenderingHints(new RenderingHints(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY));
g2d.drawImage(imageIcon.getImage(), 0, 0, width, height, null);
g2d.dispose();
return new ImageIcon(bi);
}
}
第三类：
package state_switcher;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.image.BufferedImage;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
/**
* @author Ron Brash (ron.brash@gmail.com)
*
* The concept of this class is to create a panel which
* contains a JButton which has an inline actionListener.
*
* The action listener will change the state using a static
* function from the class Main.
*/
@SuppressWarnings("serial")
public class Panel2 extends JPanel {
public Panel2() {
JPanel panel2 = new JPanel();
JButton button = new JButton("sweet");
button.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
Main.changeState(ViewState.START_STATE);
}
});
String url = "jdbc:mysql://localhost:3306/";
String user = "root";
String pass = "";
try
{
Class.forName("com.mysql.jdbc.Driver").newInstance();
Connection con = DriverManager.getConnection(url, user, pass);
Statement stt = con.createStatement();
//Create and select database
stt.execute("CREATE DATABASE IF NOT EXISTS test");
stt.execute("USE gamingplace");
int ID = 0;
ResultSet res = stt.executeQuery("SELECT * FROM products WHERE id = " + ID);
setLayout(null);
while(res.next())
{
ImageIcon imageIcon = new ImageIcon("D:\\" + res.getString("image"));
JButton button1 = new JButton(imageIcon);
add(button1).setBounds(10, 10, 300, 400);
button1.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
// display back the first panel when pressed
Main.changeState(ViewState.START_STATE);
}
}); //add an actionListener right away
}
//Free resources
res.close();
stt.close();
con.close();
}
catch(Exception e)
{
e.printStackTrace();
}
this.add(panel2);
}
public static ImageIcon resize(ImageIcon imageIcon, int width, int height)
{
BufferedImage bi = new BufferedImage(width, height, BufferedImage.TRANSLUCENT);
Graphics2D g2d = (Graphics2D) bi.createGraphics();
g2d.addRenderingHints(new RenderingHints(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY));
g2d.drawImage(imageIcon.getImage(), 0, 0, width, height, null);
g2d.dispose();
return new ImageIcon(bi);
}
}
第四级和主要级别：
package state_switcher;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
/**
* @author Ron Brash (ron.brash@gmail.com)
*
* The concept of this class is to create a JFrame which contains three
* panels:
*
* > mpanel is the master panel in which all of the other panel related
* content will be added to it
*
* > panel1 is the first panel to be displayed
*
* > panel2 is the second panel to be displayed
*
* Both panel1 and panel2 contain JButtons which will alter the enum
* viewState and depending on the state (which is determined by button
* click), the correct panel will be rendered.
*
* If you do not use a master panel, removeAll() will cause logic errors
* for whatever reason.
*/
public class Main {
private static ViewState viewState;
private static JPanel mpanel;
private static JPanel panel1;
private static JPanel panel2;
private static JFrame frame;
static JButton button = new JButton("2");
public Main() {
frame = new JFrame();
mpanel = new JPanel();
panel1 = new Panel1();
panel2 = new Panel2();
button.setName("2");
// Sets default state
changeState(ViewState.START_STATE);
frame.setSize(1200, 1000);
frame.add(mpanel);
frame.setVisible(true);
}
/**
* changeState(ViewState state)
*
* Publicly available state changer function
*
* @param state
* @return void
*/
public static void changeState(ViewState state) {
viewState = state;
System.out.println("change state: " + viewState);
switch (state) {
case START_STATE:
mpanel.setLayout(null);
mpanel.removeAll();
mpanel.add(panel1).setBounds(10, 10, 1000, 850);;
mpanel.revalidate();
mpanel.repaint();
break;
case NEXT_STATE:
mpanel.setLayout(null);
mpanel.removeAll();
mpanel.add(panel2).setBounds(10, 10, 1000, 850);
mpanel.revalidate();
mpanel.repaint();
break;
default:
System.out.println("UNKNOWN STATE!");
break;
}
}
/**
* main(String[] args)
*
* Like an opinion, everyone has one.
*
* @param args
* @return void
*/
public static void main(String[] args) {
@SuppressWarnings("unused")
Main n = new Main();
}
}