Java 将背景图像添加到我的jpanel时遇到问题，找不到错误，我也不理解错误
问题代码是这个部分，它是从我试图将图像添加到面板时开始的Java 将背景图像添加到我的jpanel时遇到问题，找不到错误，我也不理解错误,java,swing,Java,Swing,问题代码是这个部分，它是从我试图将图像添加到面板时开始的 import java.awt.*; import java.awt.event.*; import javax.swing.*; public class Test { public static void panel1() { JFrame frame=new JFrame("@b's metric calculator"); //Color b=new Co
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class Test
{
public static void panel1()
{
JFrame frame=new JFrame("@b's metric calculator");
//Color b=new Color(0,150,255);
//JPanel Cr=new JPanel();
final JTextField textField = new JTextField(10);
//textField.setBackgound(0,255,220);
JButton button=new JButton("Enter Centimeter");
final JTextField textFiel= new JTextField("Your result will be here",20);
String[] list = {"cm-inch","cm-meter","cm-feet","inch-feet"};
/*The <string> added below is to avoid "unchecked or unsafe operations” warning in Java ,
if passing integer set it <Integer>*/
final JComboBox<String> list1 = new JComboBox<String>(list);
list1.setSelectedIndex(0);
JButton submit=new JButton("Submit");
submit.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
//textFiel.setText(textField.getText());
//following command converts textfild value to integer
int centi=Integer.parseInt(textField.getText());
//----------------------------------------------------
//double area = 3.14*radius*radius;
int cb = list1.getSelectedIndex();//to get the index of selected item(eg. 0,1,2..)
if(cb==0)
{
Double inch = centi/2.54;
//following command converts double to string
String out = Double.toString(inch);
//-----------------------------------------
textFiel.setText(out);
}
else if(cb==1)
{
Double meter = centi/100.00;
String out = Double.toString(meter);
textFiel.setText(out);
}
else if(cb==2)
{
Double feet = centi/30.48;
String out = Double.toString(feet);
textFiel.setText(out);
}
else
{
Double feet = centi/12.00;
String out = Double.toString(feet);
textFiel.setText(out);
}
}
});
//c.setBackground(b);
frame.add(new Cr());
Cr.add(button);
Cr.add(textField);
Cr.add(list1);
Cr.add(submit);
Cr.add(textFiel);
button.setPreferredSize(new Dimension(150,30));
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(400,300);
frame.setVisible(true);
JOptionPane.showMessageDialog(frame,"Welcome \n enter centimeter in blank box\n Select your choice\n then press submit");
}
class Cr extends JPanel{
ImageIcon image = new ImageIcon("C:/Users/Public/Pictures/Sample Pictures/Desert.jpg");
public void paint( Graphics g ) {
Dimension d = getSize();
for( int x = 0; x < d.width; x += image.getIconWidth() )
for( int y = 0; y < d.height; y += image.getIconHeight() )
g.drawImage( image.getImage(), x, y, null, null );
super.paint(g);
}
}
public static void main(String[] args)
{
javax.swing.SwingUtilities.invokeLater(new Runnable()
{
public void run() {
panel1();
}
});
}
}
我不想评论什么
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class Test extends JPanel{
public Test() {
setOpaque(false);
setLayout(new FlowLayout());
}
public static void main(String[] args) {
JFrame frame = new JFrame("@b's metric calculator");
final JTextField textField = new JTextField(10);
JButton button = new JButton("Enter Centimeter");
final JTextField textFiel = new JTextField("Your result will be here", 20);
String[] list = {"cm-inch", "cm-meter", "cm-feet", "inch-feet"};
/*The <string> added below is to avoid "unchecked or unsafe operations” warning in Java ,
if passing integer set it <Integer>*/
final JComboBox<String> list1 = new JComboBox<String>(list);
list1.setSelectedIndex(0);
JButton submit = new JButton("Submit");
Test Cr = new Test();
submit.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
//textFiel.setText(textField.getText());
//following command converts textfild value to integer
int centi = Integer.parseInt(textField.getText());
//----------------------------------------------------
//double area = 3.14*radius*radius;
int cb = list1.getSelectedIndex();//to get the index of selected item(eg. 0,1,2..)
if (cb == 0) {
Double inch = centi / 2.54;
//following command converts double to string
String out = Double.toString(inch);
//-----------------------------------------
textFiel.setText(out);
} else if (cb == 1) {
Double meter = centi / 100.00;
String out = Double.toString(meter);
textFiel.setText(out);
} else if (cb == 2) {
Double feet = centi / 30.48;
String out = Double.toString(feet);
textFiel.setText(out);
} else {
Double feet = centi / 12.00;
String out = Double.toString(feet);
textFiel.setText(out);
}
}
});
frame.add(Cr);
Cr.add(button);
Cr.add(textField);
Cr.add(list1);
Cr.add(submit);
Cr.add(textFiel);
button.setPreferredSize(new Dimension(150, 30));
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(400, 300);
frame.setVisible(true);
JOptionPane.showMessageDialog(frame, "Welcome \n enter centimeter in blank box\n Select your choice\n then press submit");
}
public void paint(Graphics g)
{
// Loads the background image and stores in img object.
Image img = Toolkit.getDefaultToolkit().getImage("C:\\Users\\Administrator\\Documents\\JAVA\\My java programs\\hd_wall_11493.jpg");
// Draws the img to the BackgroundPanel.
g.drawImage(img,0,0,getSize().width,getSize().height,this);
super.paint(g);
}
}
我不想评论什么
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class Test extends JPanel{
public Test() {
setOpaque(false);
setLayout(new FlowLayout());
}
public static void main(String[] args) {
JFrame frame = new JFrame("@b's metric calculator");
final JTextField textField = new JTextField(10);
JButton button = new JButton("Enter Centimeter");
final JTextField textFiel = new JTextField("Your result will be here", 20);
String[] list = {"cm-inch", "cm-meter", "cm-feet", "inch-feet"};
/*The <string> added below is to avoid "unchecked or unsafe operations” warning in Java ,
if passing integer set it <Integer>*/
final JComboBox<String> list1 = new JComboBox<String>(list);
list1.setSelectedIndex(0);
JButton submit = new JButton("Submit");
Test Cr = new Test();
submit.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
//textFiel.setText(textField.getText());
//following command converts textfild value to integer
int centi = Integer.parseInt(textField.getText());
//----------------------------------------------------
//double area = 3.14*radius*radius;
int cb = list1.getSelectedIndex();//to get the index of selected item(eg. 0,1,2..)
if (cb == 0) {
Double inch = centi / 2.54;
//following command converts double to string
String out = Double.toString(inch);
//-----------------------------------------
textFiel.setText(out);
} else if (cb == 1) {
Double meter = centi / 100.00;
String out = Double.toString(meter);
textFiel.setText(out);
} else if (cb == 2) {
Double feet = centi / 30.48;
String out = Double.toString(feet);
textFiel.setText(out);
} else {
Double feet = centi / 12.00;
String out = Double.toString(feet);
textFiel.setText(out);
}
}
});
frame.add(Cr);
Cr.add(button);
Cr.add(textField);
Cr.add(list1);
Cr.add(submit);
Cr.add(textFiel);
button.setPreferredSize(new Dimension(150, 30));
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(400, 300);
frame.setVisible(true);
JOptionPane.showMessageDialog(frame, "Welcome \n enter centimeter in blank box\n Select your choice\n then press submit");
}
public void paint(Graphics g)
{
// Loads the background image and stores in img object.
Image img = Toolkit.getDefaultToolkit().getImage("C:\\Users\\Administrator\\Documents\\JAVA\\My java programs\\hd_wall_11493.jpg");
// Draws the img to the BackgroundPanel.
g.drawImage(img,0,0,getSize().width,getSize().height,this);
super.paint(g);
}
}
我会向你解释你的错误： 您的测试方法是静态方法。它不能直接访问非静态方法/变量。这非常有意义，如果您想让我详细说明，请发表评论。静态方法和变量只能访问静态成员。您需要创建静态成员的对象，该对象可以访问其他非静态成员 至于代码中需要的更正，mKorbel的解决方案是完美的。但是，要将图像添加到JPanel，最好将其添加为JLabel，而不是绘制图像：
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class Test {
public Test() {
JFrame frame = new JFrame("@b's metric calculator");
//Color b=new Color(0,150,255);
//JPanel Cr=new JPanel();
final JTextField textField = new JTextField(10);
//textField.setBackgound(0,255,220);
JButton button = new JButton("Enter Centimeter");
final JTextField textFiel = new JTextField("Your result will be here", 20);
String[] list = {"cm-inch", "cm-meter", "cm-feet", "inch-feet"};
/*The <string> added below is to avoid "unchecked or unsafe operations” warning in Java ,
if passing integer set it <Integer>*/
final JComboBox<String> list1 = new JComboBox<String>(list);
list1.setSelectedIndex(0);
JButton submit = new JButton("Submit");
submit.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
//textFiel.setText(textField.getText());
//following command converts textfild value to integer
int centi = Integer.parseInt(textField.getText());
//----------------------------------------------------
//double area = 3.14*radius*radius;
int cb = list1.getSelectedIndex();//to get the index of selected item(eg. 0,1,2..)
if (cb == 0) {
Double inch = centi / 2.54;
//following command converts double to string
String out = Double.toString(inch);
//-----------------------------------------
textFiel.setText(out);
} else if (cb == 1) {
Double meter = centi / 100.00;
String out = Double.toString(meter);
textFiel.setText(out);
} else if (cb == 2) {
Double feet = centi / 30.48;
String out = Double.toString(feet);
textFiel.setText(out);
} else {
Double feet = centi / 12.00;
String out = Double.toString(feet);
textFiel.setText(out);
}
}
});
//c.setBackground(b);
Cr cr = new Cr();
cr.add(button);
cr.add(textField);
cr.add(list1);
cr.add(submit);
cr.add(textFiel);
button.setPreferredSize(new Dimension(150, 30));
frame.add(cr);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(400, 300);
frame.setVisible(true);
JOptionPane.showMessageDialog(frame, "Welcome \n enter centimeter in blank box\n Select your choice\n then press submit");
}
class Cr extends JPanel {
private static final long serialVersionUID = 1L;
private ImageIcon image = new ImageIcon("C:/Users/Public/Pictures/Sample Pictures/Desert.jpg");
@Override
public void paint(Graphics g) {
Dimension d = getSize();
for (int x = 0; x < d.width; x += image.getIconWidth()) {
for (int y = 0; y < d.height; y += image.getIconHeight()) {
g.drawImage(image.getImage(), x, y, null, null);
}
}
super.paint(g);
}
}
public static void main(String[] args) {
javax.swing.SwingUtilities.invokeLater(new Runnable() {
public void run() {
Test test = new Test();
}
});
}
}
BufferedImage myPicture = ImageIO.read(new File("path-to-file"));
JLabel picLabel = new JLabel(new ImageIcon( myPicture ));
frame.add( picLabel );//see javadocs for JLabel for more info
我会向你解释你的错误： 您的测试方法是静态方法。它不能直接访问非静态方法/变量。这非常有意义，如果您想让我详细说明，请发表评论。静态方法和变量只能访问静态成员。您需要创建静态成员的对象，该对象可以访问其他非静态成员 至于代码中需要的更正，mKorbel的解决方案是完美的。但是，要将图像添加到JPanel，最好将其添加为JLabel，而不是绘制图像：
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class Test {
public Test() {
JFrame frame = new JFrame("@b's metric calculator");
//Color b=new Color(0,150,255);
//JPanel Cr=new JPanel();
final JTextField textField = new JTextField(10);
//textField.setBackgound(0,255,220);
JButton button = new JButton("Enter Centimeter");
final JTextField textFiel = new JTextField("Your result will be here", 20);
String[] list = {"cm-inch", "cm-meter", "cm-feet", "inch-feet"};
/*The <string> added below is to avoid "unchecked or unsafe operations” warning in Java ,
if passing integer set it <Integer>*/
final JComboBox<String> list1 = new JComboBox<String>(list);
list1.setSelectedIndex(0);
JButton submit = new JButton("Submit");
submit.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
//textFiel.setText(textField.getText());
//following command converts textfild value to integer
int centi = Integer.parseInt(textField.getText());
//----------------------------------------------------
//double area = 3.14*radius*radius;
int cb = list1.getSelectedIndex();//to get the index of selected item(eg. 0,1,2..)
if (cb == 0) {
Double inch = centi / 2.54;
//following command converts double to string
String out = Double.toString(inch);
//-----------------------------------------
textFiel.setText(out);
} else if (cb == 1) {
Double meter = centi / 100.00;
String out = Double.toString(meter);
textFiel.setText(out);
} else if (cb == 2) {
Double feet = centi / 30.48;
String out = Double.toString(feet);
textFiel.setText(out);
} else {
Double feet = centi / 12.00;
String out = Double.toString(feet);
textFiel.setText(out);
}
}
});
//c.setBackground(b);
Cr cr = new Cr();
cr.add(button);
cr.add(textField);
cr.add(list1);
cr.add(submit);
cr.add(textFiel);
button.setPreferredSize(new Dimension(150, 30));
frame.add(cr);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(400, 300);
frame.setVisible(true);
JOptionPane.showMessageDialog(frame, "Welcome \n enter centimeter in blank box\n Select your choice\n then press submit");
}
class Cr extends JPanel {
private static final long serialVersionUID = 1L;
private ImageIcon image = new ImageIcon("C:/Users/Public/Pictures/Sample Pictures/Desert.jpg");
@Override
public void paint(Graphics g) {
Dimension d = getSize();
for (int x = 0; x < d.width; x += image.getIconWidth()) {
for (int y = 0; y < d.height; y += image.getIconHeight()) {
g.drawImage(image.getImage(), x, y, null, null);
}
}
super.paint(g);
}
}
public static void main(String[] args) {
javax.swing.SwingUtilities.invokeLater(new Runnable() {
public void run() {
Test test = new Test();
}
});
}
}
BufferedImage myPicture = ImageIO.read(new File("path-to-file"));
JLabel picLabel = new JLabel(new ImageIcon( myPicture ));
frame.add( picLabel );//see javadocs for JLabel for more info
我觉得这可能还是会出现错误。你编译了吗？我可能错了-对我是那个意思。我想我得读一读-thks用于回复程序工作时无错误，但我不理解私有静态final long serialVersionUID=1L，这意味着什么，而且图像不只是显示空白背景，请你再次帮助我。thks@TomC：参见Bloch，《有效的Java》，第74项：明智地实现可序列化。我感觉这可能仍然会弹出一个错误。你编译了吗？我可能错了-对我是那个意思。我想我得读一读-thks用于回复程序工作时无错误，但我不理解私有静态final long serialVersionUID=1L，这意味着什么，而且图像不只是显示空白背景，请你再次帮助我。thks@TomC：参见Bloch，《有效的Java》，第74项：明智地实现可序列化。thks，我对Java不熟悉，所以对静态内容知之甚少。另外，mKorbel的解决方案非常好，但我不了解私有静态final long serialVersionUID=1L，这意味着什么，而且图像不仅显示空白背景，请您帮助我，图像位于“C”驱动器中-我的图片。私有静态最终long serialVersionUID=1L；是存储程序串行版本的变量。在您的案例中，IDE添加的是冗余的。如果你想的话，你可以删除它。我这样问一定很愚蠢，但我是初学者，所以请原谅我这样问，我应该在cr类中使用它而不是ImageIcon吗？在你创建fame=new JFrame并添加其他组件的panel1方法中使用它。这就是您使用frame对象的地方，只有frame.addpicLabel；最后我找到了为什么我的图像没有加载，它应该在我的类文件夹中，thks为你们的hlp家伙。谢谢你的帮助。我是java新手，所以对静态知识知之甚少。另外，mKorbel的解决方案非常好，但我不了解私有静态final long serialVersionUID=1L，这意味着什么，而且图像不仅显示空白背景，请您帮助我，图像位于“C”驱动器中-我的图片。私有静态最终long serialVersionUID=1L；是存储程序串行版本的变量。在您的案例中，IDE添加的是冗余的。如果你想的话，你可以删除它。我这样问一定很愚蠢，但我是初学者，所以请原谅我这样问，我应该在cr类中使用它而不是ImageIcon吗？在你创建fame=new JFrame并添加其他组件的panel1方法中使用它。这就是您使用frame对象的地方，只有frame.addpicLabel；最后我找到了为什么我的图像没有加载，它应该在我的类文件夹中，thks为你们的hlp家伙。谢谢你的帮助。当你扩展一个JPanel时，千万不要覆盖它的油漆。。。方法，在内部始终选择paintComponent…`，这就是要走的路，只要是co
请看一下这个例子。此外，为了使框架位于屏幕中央，只需在frameObject.setVisibletrue；之前写入frameObject.setLocationRelativeTonull即可；，就是这样：-thks代表中央屏幕的代码。非常欢迎您并保持微笑：-当您扩展JPanel时，请不要覆盖它的绘画。。。方法，在内部始终选择paintComponent…`，这就是要走的路，就所关心的问题而言，请看一下这个示例。此外，为了使框架位于屏幕中央，只需在frameObject.setVisibletrue；之前写入frameObject.setLocationRelativeTonull即可；，就这样：-thks代表中央屏幕的代码。非常欢迎您并保持微笑：-