在Java中使用MVC设置KeyListener [英] Setting up KeyListeners using the MVC in java
本文介绍了在Java中使用MVC设置KeyListener的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
我正在尝试使自己成为Java的计算器.我认为最好为我的代码实现MVC(模型视图控制器)设计.我有一些基础知识可以工作，计算器确实可以工作，但问题是我无法弄清楚我在听键的实现方面出了什么问题.目前，我可以使用动作侦听器单击按钮，并使用数字值更新该字段，并可以使用按钮进行加，减，乘，除以及清除.因此，我目前唯一真正想到的就是尝试允许用户(我自己)使用键盘上的数字键盘将值附加到字段上的选项，无论如何这是我的代码.
I am trying to make myself a calculator in Java. I figured it would be best to implement the MVC (model view controller) design for my code. I have some of the basics working, the calculator does actually work, the issue is i cannot figure out where i am going wrong with the implementation of listening to keys. At the moment i have the ability to click on the buttons using the action listener and updating the field with a numeric value and the buttons to add, subtract, multiply, divide and also to clear. So really the only thing on my mind at the moment is trying to allow the user (myself) the option to use the number pad on the keyboard to append values to the field, anyways here is my code.
此视图
package Calculator;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.event.ActionListener;
import java.awt.event.KeyListener;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTextArea;
public class CalcFrame extends JFrame{
private Dimension d = new Dimension(300,300);
JPanel panel1 = new JPanel();
JPanel panel2 = new JPanel();
JButton equals = new JButton("=");
JButton addBtn = new JButton("+");
JButton subtractBtn = new JButton("-");
JButton multiplyBtn = new JButton("*");
JButton divideBtn = new JButton("/");
JTextArea field = new JTextArea(1,20);
JButton numBtn[] = new JButton[11];
String numTxt[] = {"0","1","2","3","4","5","6","7","8","9","C"};
Color newColor = new Color(10,70,40);
int x = 50, y = 0;
public CalcFrame(){
this.setSize(d);
this.setResizable(false);
// frame.setVisible(true);
this.setTitle("Marks Calculator");
this.setIconImage(new ImageIcon(this.getClass().getResource("emblem.png")).getImage());
for(int i = 0; i < numBtn.length; i++){
numBtn[i] = new JButton(numTxt[i]);
numBtn[i].setSize(50, 30);
}
for(int i = 0; i <numBtn.length; i++){
numBtn[0].setLocation(10,180);
numBtn[1].setLocation(10,140);
numBtn[2].setLocation(65,140);
numBtn[3].setLocation(120,140);
numBtn[4].setLocation(175,140);
numBtn[5].setLocation(10,100);
numBtn[6].setLocation(65,100);
numBtn[7].setLocation(120,100);
numBtn[8].setLocation(175,100);
numBtn[9].setLocation(10,60);
numBtn[10].setLocation(175,20);
panel2.add(numBtn[i]);
}
field.setLocation(10, 10);
field.setSize(280,30);
field.setEditable(false);
field.setFocusable(true);
panel1.setSize(300, 50);
panel1.setLayout(null);
this.add(panel1);
panel2.setSize(300, 250);
panel2.setBackground(newColor);
panel2.setLocation(0, 51);
panel2.setLayout(null);
this.add(panel2);
equals.setLocation(230,180);
equals.setSize(50, 30);
panel2.add(equals);
addBtn.setLocation(230, 140);
addBtn.setSize(50,30);
panel2.add(addBtn);
subtractBtn.setLocation(230, 100);
subtractBtn.setSize(50,30);
panel2.add(subtractBtn);
multiplyBtn.setLocation(230, 60);
multiplyBtn.setSize(50,30);
panel2.add(multiplyBtn);
divideBtn.setLocation(230, 20);
divideBtn.setSize(50,30);
panel2.add(divideBtn);
panel1.add(field);
this.setLocationRelativeTo(rootPane);
this.setLayout(null);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
public void addKeyL(KeyListener keyp){
addKeyListener(keyp);
}
public void addListener(ActionListener listener){
addBtn.addActionListener(listener);
subtractBtn.addActionListener(listener);
equals.addActionListener(listener);
multiplyBtn.addActionListener(listener);
divideBtn.addActionListener(listener);
for(int i = 0; i < numBtn.length; i++){
numBtn[i].addActionListener(listener);
}
}
public int getFieldText(){
return Integer.parseInt(field.getText());
}
public void setFieldText(){
field.setText("");
}
public void setAnswer(int solution){
field.setText(Integer.toString(solution));
}
}
这是模型
package Calculator;
public class Calculations {
private int total;
public void addNumbers(int a, int b){
total = a + b;
}
public void subtractNumbers(int a, int b){
total = a - b;
}
public void multiplyNumbers(int a, int b){
total = a * b;
}
public void divideNumbers(int a, int b){
total = a / b;
}
public int getTotal(){
return total;
}
}
这是控制器
package Calculator;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
public class KeyEvents{
private boolean isAdd = false;
private boolean isSubtract = false;
private boolean isDivide = false;
private boolean isMultiply = false;
private CalcFrame view = new CalcFrame();
private Calculations model = new Calculations();
int a = 0, b = 0, answer;
int counter = 0;
public KeyEvents(CalcFrame view, Calculations model){
this.view = view;
this.model = model;
this.view.addListener(new CalcListener());
this.view.addKeyL(new CalcListener());
}
class CalcListener implements ActionListener, KeyListener{
@Override
public void actionPerformed(ActionEvent e) {
if(e.getSource().equals(view.addBtn)){
a = view.getFieldText();
view.field.setText("");
isAdd = true;
isSubtract = false;
isDivide = false;
isMultiply = false;
}
if(e.getSource().equals(view.numBtn[0])){
view.field.append("0");
}
if(e.getSource().equals(view.numBtn[1])){
view.field.append("1");
}
if(e.getSource().equals(view.numBtn[2])){
view.field.append("2");
}
if(e.getSource().equals(view.numBtn[3])){
view.field.append("3");
}
if(e.getSource().equals(view.numBtn[4])){
view.field.append("4");
}
if(e.getSource().equals(view.numBtn[5])){
view.field.append("5");
}
if(e.getSource().equals(view.numBtn[6])){
view.field.append("6");;
}
if(e.getSource().equals(view.numBtn[7])){
view.field.append("7");
}
if(e.getSource().equals(view.numBtn[8])){
view.field.append("8");
}
if(e.getSource().equals(view.numBtn[9])){
view.field.append("9");
}
if(e.getSource().equals(view.numBtn[10])){
view.field.setText("");
}
if(e.getSource().equals(view.subtractBtn)){
a = view.getFieldText();
view.field.setText("");
isAdd = false;
isSubtract = true;
isDivide = false;
isMultiply = false;
}
if(e.getSource().equals(view.multiplyBtn)){
a = view.getFieldText();
view.field.setText("");
isAdd = false;
isSubtract = false;
isDivide = false;
isMultiply = true;
}
if(e.getSource().equals(view.divideBtn)){
a = view.getFieldText();
view.field.setText("");
isAdd = false;
isSubtract = false;
isDivide = true;
isMultiply = false;
}
if(e.getSource().equals(view.equals)){
b = view.getFieldText();
if(isAdd == true){
view.setFieldText();
model.addNumbers(a, b);
view.setAnswer(model.getTotal());
}
if(isSubtract == true){
view.setFieldText();
model.subtractNumbers(a, b);
view.setAnswer(model.getTotal());
}
if(isMultiply == true){
view.setFieldText();
model.multiplyNumbers(a, b);
view.setAnswer(model.getTotal());
}
if(isDivide == true){
view.setFieldText();
model.divideNumbers(a, b);
view.setAnswer(model.getTotal());
}
}
}
@Override
public void keyTyped(KeyEvent e) {
if(e.getSource().equals(KeyEvent.VK_0)){
System.out.println("sjkdhlkj");
}
if(e.getSource().equals(KeyEvent.VK_1)){
view.field.append("1");
}
if(e.getSource().equals(KeyEvent.VK_2)){
view.field.append("2");
}
if(e.getSource().equals(KeyEvent.VK_3)){
view.field.append("3");
}
if(e.getSource().equals(KeyEvent.VK_4)){
view.field.append("4");
}
if(e.getSource().equals(KeyEvent.VK_5)){
view.field.append("5");
}
if(e.getSource().equals(KeyEvent.VK_6)){
view.field.append("6");
}
if(e.getSource().equals(KeyEvent.VK_7)){
view.field.append("7");
}
if(e.getSource().equals(KeyEvent.VK_8)){
view.field.append("8");
}
if(e.getSource().equals(KeyEvent.VK_9)){
view.field.append("9");
}
}
@Override
public void keyPressed(KeyEvent e) {
if(e.getSource().equals(KeyEvent.VK_0)){
System.out.println("sjkdhlkj");
}
if(e.getSource().equals(KeyEvent.VK_1)){
view.field.append("1");
}
if(e.getSource().equals(KeyEvent.VK_2)){
view.field.append("2");
}
if(e.getSource().equals(KeyEvent.VK_3)){
view.field.append("3");
}
if(e.getSource().equals(KeyEvent.VK_4)){
view.field.append("4");
}
if(e.getSource().equals(KeyEvent.VK_5)){
view.field.append("5");
}
if(e.getSource().equals(KeyEvent.VK_6)){
view.field.append("6");
}
if(e.getSource().equals(KeyEvent.VK_7)){
view.field.append("7");
}
if(e.getSource().equals(KeyEvent.VK_8)){
view.field.append("8");
}
if(e.getSource().equals(KeyEvent.VK_9)){
view.field.append("9");
}
}
@Override
public void keyReleased(KeyEvent e) {
if(e.getSource().equals(KeyEvent.VK_0)){
System.out.println("sjkdhlkj");
}
if(e.getSource().equals(KeyEvent.VK_1)){
view.field.append("1");
}
if(e.getSource().equals(KeyEvent.VK_2)){
view.field.append("2");
}
if(e.getSource().equals(KeyEvent.VK_3)){
view.field.append("3");
}
if(e.getSource().equals(KeyEvent.VK_4)){
view.field.append("4");
}
if(e.getSource().equals(KeyEvent.VK_5)){
view.field.append("5");
}
if(e.getSource().equals(KeyEvent.VK_6)){
view.field.append("6");
}
if(e.getSource().equals(KeyEvent.VK_7)){
view.field.append("7");
}
if(e.getSource().equals(KeyEvent.VK_8)){
view.field.append("8");
}
if(e.getSource().equals(KeyEvent.VK_9)){
view.field.append("9");
}
}
}
}
它的tl; dr是，我无法使keyListener正常工作，我尝试将keyListener分配给字段panel1，panel2和this.分开.我们一如既往地为您提供帮助.
the tl;dr of this is, i am unable to get keyListener to work correctly, i have tried assigning the keyListener to the field, panel1, panel2 and this. seperately. Assistance is appreciated as always.
〜更新〜 我决定尝试一下GitHub，并在上面添加了我的代码.我希望它可以使我的代码更易于理解，甚至可以理解，以便人们可以随意使用. https://github.com/niroshido/TestCalculator/tree/master/Calculator
~UPDATE~ I decided to give GitHub a try and have just put my code up on to it. I hope it would make my code easier to understand or even forkable so a person can mess around with it. https://github.com/niroshido/TestCalculator/tree/master/Calculator
推荐答案
使用键绑定.一个简单的例子:
Use Key Bindings. A simple example:
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.border.*;
public class CalculatorPanel extends JPanel
{
private JTextField display;
public CalculatorPanel()
{
Action numberAction = new AbstractAction()
{
@Override
public void actionPerformed(ActionEvent e)
{
display.setCaretPosition( display.getDocument().getLength() );
display.replaceSelection(e.getActionCommand());
}
};
setLayout( new BorderLayout() );
display = new JTextField();
display.setEditable( false );
display.setHorizontalAlignment(JTextField.RIGHT);
add(display, BorderLayout.NORTH);
JPanel buttonPanel = new JPanel();
buttonPanel.setLayout( new GridLayout(0, 5) );
add(buttonPanel, BorderLayout.CENTER);
for (int i = 0; i < 10; i++)
{
String text = String.valueOf(i);
JButton button = new JButton( text );
button.addActionListener( numberAction );
button.setBorder( new LineBorder(Color.BLACK) );
button.setPreferredSize( new Dimension(50, 50) );
buttonPanel.add( button );
KeyStroke pressed = KeyStroke.getKeyStroke(text);
InputMap inputMap = button.getInputMap(JComponent.WHEN_IN_FOCUSED_WINDOW);
inputMap.put(pressed, text);
button.getActionMap().put(text, numberAction);
}
}
private static void createAndShowUI()
{
// UIManager.put("Button.margin", new Insets(10, 10, 10, 10) );
JFrame frame = new JFrame("Calculator Panel");
frame.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
frame.add( new CalculatorPanel() );
frame.pack();
frame.setLocationRelativeTo( null );
frame.setVisible(true);
}
public static void main(String[] args)
{
EventQueue.invokeLater(new Runnable()
{
public void run()
{
createAndShowUI();
}
});
}
}
这篇关于在Java中使用MVC设置KeyListener的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
查看全文
