我正在研究这段代码,可以在以下位置找到
http://pastebin.com/7bCFtUHL
基本上,我想添加一个清除方法(按钮),以解决数独问题。
我尝试过遍历每个单元格并将其设置为null的循环,但是我不确定如何准确地连接它。我也不确定我必须在哪个类中创建它,以便可以将其连接到具有其他按钮的GUI。
编辑:
这是我目前得到的明确方法
public void clearCells(){
for (int y = 0; y < 9; y++) {
for (int x = 0; x < 9; x++) {
cells[y][x] = null;
cells[y][x].setText("");
}
}
}
现在,我需要将其附加到另一个类的JButton中,这怎么可能?
我的清除按钮看起来像这样
JButton clear = new JButton("Clear");
clear.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e)
{
//Code
}
}
);
我需要在actionPerformed方法中添加什么代码才能将其与我的clearCells方法连接?
最佳答案
同样,我将clear方法的“实质”放在模型本身中。解决方案的一般形式是:
clear.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
myModel.clearCells();
}
});
Model类将具有一个公共的
void clearCells()
方法,该方法遍历单元格并清除它们。编辑1
注意:是的,我确实查看了您的pastebin代码链接,我看到的一个大问题是您的SwingSudokuBoard类扩展了SudokuBoard类,这是对继承的滥用,您应该改用组合。 SwingSudokuBoard类应包含SudokuBoard对象的实例并在其上调用方法。
编辑2
你问:
我不确定我是否能完全理解你。您希望我在获得按钮的同一个类中拥有clear方法,但随后我无法调用单元格。我添加了x.clearCells();而x是什么?我的主类是SwingSudokuBoard.clearCells(); ?无论如何,如果我添加您所说的内容,该程序就会抱怨它希望clearCells方法和单元格是静态的。但是,如果将它们置于静态,则会得到NullPointerException。
我认为您需要使用“模型-视图-控件”(MVC)模式或它的缩写版本,也许是其中的一种,因为程序很小,因此您可以将视图与控件结合起来。我建议您有一个单独的模型类,这里可能是SudokuBoard类,然后是视图类,这里可能是SwingSudokuBoard类。您视图的控制方法(ActionListeners)将调用模型的
clearCells()
方法。并且不要在这里使用静态任何东西。编辑3
你问:
我认为有些话。型号:SudokuBoard;视图:SwingSudokuBoard;控制:SwingSudoKiller。那会如何?我将把ActionListener张贴在控件中。其他班级的情况如何?由于我假设清除方法位于要放在SudokuBoard中的模型中,但无法与那里的单元连接。
我不是专业人士,也没有接受过正式的编程培训,所以理论是我的弱点之一,但是我对MVC的解释是,视图会听取模型并在模型通知更改时进行更新,并且控件侦听视图,并通过通知模型来响应视图更改。这种精确的模式具有变化形式,不需要完全跟在字母后面,但是所有这些的关键是在您的代码中尽可能地分离出单独的关注点,以便“耦合”(之间的直接连接数类)为低或“松散”,而“内聚力”(处理相同问题的代码)为高或“紧”。
在您的程序中,就像您在做的一样,我再次使用匿名内部侦听器将视图和控件结合在一起。我要有一个视图/控件,它是SwingSudokuBoard类,将SudokuBoard类的一个实例保存为类字段,并在SudokuBoard字段上具有视图/控件的匿名侦听器调用方法。当我以前做过这种事情时,我通过给它提供一个SwingPropertyChangeSupport对象以及公共的
addPropertyChangeListener(...)
和removePropertyChangeListener(...)
方法来提供对模型观察的支持。这样,视图可以轻松响应模型中的更改。您声明:
由于我假设清除方法位于要放在SudokuBoard中的模型中,但无法与那里的单元连接。
我不确定您的意思。该模型保存单元格。也许您不是说模型所拥有的逻辑单元,而是视图所拥有的显示单元。该视图将向模型添加一个侦听器,并在收到有关模型更改的通知时,将向模型询问其数据,并使用该数据来更新可视化的单元格。
编辑4
例如:
import java.awt.event.ActionEvent;
import java.awt.event.KeyEvent;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import javax.swing.*;
import javax.swing.event.SwingPropertyChangeSupport;
public class OverlySimpleModelView {
private static void createAndShowGui() {
Model model = new Model();
ViewControl viewControl = new ViewControl(model);
JFrame frame = new JFrame("OverlySimpleModelView");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(viewControl.getMainComponent());
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}
class ViewControl {
private JPanel mainPanel = new JPanel();
private JTextField number1Field = new JTextField(5);
private JTextField number2Field = new JTextField(5);
private JTextField productField = new JTextField(5);
private Model model;
public ViewControl(Model model) {
this.model = model;
model.addPropertyChangeListener(new MyPropChngListener());
productField.setEditable(false);
productField.setFocusable(false);
mainPanel.add(number1Field);
mainPanel.add(new JLabel(" * "));
mainPanel.add(number2Field);
mainPanel.add(new JLabel(" = "));
mainPanel.add(productField);
CalculateAction calculateAction = new CalculateAction("Calculate", KeyEvent.VK_C);
mainPanel.add(new JButton(calculateAction));
number1Field.addActionListener(calculateAction);
number2Field.addActionListener(calculateAction);
mainPanel.add(new JButton(new ClearAction("Clear", KeyEvent.VK_L)));
}
public JComponent getMainComponent() {
return mainPanel;
}
private class MyPropChngListener implements PropertyChangeListener {
@Override
public void propertyChange(PropertyChangeEvent evt) {
number1Field.setText(String.valueOf(model.getNumber1()));
number2Field.setText(String.valueOf(model.getNumber2()));
productField.setText(String.valueOf(model.calculateProduct()));
}
}
private class CalculateAction extends AbstractAction {
public CalculateAction(String text, int keyCode) {
super(text);
putValue(MNEMONIC_KEY, keyCode);
}
@Override
public void actionPerformed(ActionEvent evt) {
try {
double number1 = Double.parseDouble(number1Field.getText());
double number2 = Double.parseDouble(number2Field.getText());
model.setNumber1(number1);
model.setNumber2(number2);
} catch (NumberFormatException e) {
e.printStackTrace();
}
}
}
private class ClearAction extends AbstractAction {
public ClearAction(String text, int keyCode) {
super(text);
putValue(MNEMONIC_KEY, keyCode); // to allow buttons a mnemonic letter
}
@Override
public void actionPerformed(ActionEvent evt) {
model.clear();
}
}
}
class Model {
public static final String NUMBERS_CHANGED = "numbers changed";
private double number1 = 0.0;
private double number2 = 0.0;
private SwingPropertyChangeSupport propChngSupport =
new SwingPropertyChangeSupport(this);
public double getNumber1() {
return number1;
}
public double getNumber2() {
return number2;
}
public void clear() {
setNumber1(0.0);
setNumber2(0.0);
}
// make number1 field a "bound" property, one that notifies listeners if it is changed.
public void setNumber1(double number1) {
Double oldValue = this.number1;
Double newValue = number1;
this.number1 = number1;
propChngSupport.firePropertyChange(NUMBERS_CHANGED, oldValue , newValue);
}
// ditto for the number2 field
public void setNumber2(double number2) {
Double oldValue = this.number2;
Double newValue = number2;
this.number2 = number2;
propChngSupport.firePropertyChange(NUMBERS_CHANGED, oldValue , newValue);
}
public double calculateProduct() {
return number1 * number2;
}
public void addPropertyChangeListener(PropertyChangeListener listener) {
propChngSupport.addPropertyChangeListener(listener);
}
public void removePropertyChangeListener(PropertyChangeListener listener) {
propChngSupport.removePropertyChangeListener(listener);
}
}
也许更好,因为它使用数字数组:
import java.awt.event.ActionEvent;
import java.awt.event.KeyEvent;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import javax.swing.*;
import javax.swing.event.SwingPropertyChangeSupport;
public class OverlySimpleModelView {
private static void createAndShowGui() {
Model model = new Model(5);
ViewControl viewControl = new ViewControl(model);
JFrame frame = new JFrame("OverlySimpleModelView");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(viewControl.getMainComponent());
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}
class ViewControl {
private JPanel mainPanel = new JPanel();
private JTextField[] numberFields;
private JTextField productField = new JTextField(5);
private Model model;
public ViewControl(Model model) {
this.model = model;
model.addPropertyChangeListener(new MyPropChngListener());
productField.setEditable(false);
productField.setFocusable(false);
CalculateAction calculateAction = new CalculateAction("Calculate", KeyEvent.VK_C);
numberFields = new JTextField[model.getNumberFieldsLength()];
for (int i = 0; i < numberFields.length; i++) {
numberFields[i] = new JTextField("0.0", 5);
mainPanel.add(numberFields[i]);
numberFields[i].addActionListener(calculateAction);
if (i < numberFields.length - 1) {
mainPanel.add(new JLabel(" + "));
} else {
mainPanel.add(new JLabel(" = "));
}
}
mainPanel.add(productField);
mainPanel.add(new JButton(calculateAction));
mainPanel.add(new JButton(new ClearAction("Clear", KeyEvent.VK_L)));
}
public JComponent getMainComponent() {
return mainPanel;
}
private class MyPropChngListener implements PropertyChangeListener {
@Override
public void propertyChange(PropertyChangeEvent evt) {
for (int i = 0; i < numberFields.length; i++) {
numberFields[i].setText(String.valueOf(model.getNumber(i)));
}
productField.setText(String.valueOf(model.calculateSum()));
}
}
private class CalculateAction extends AbstractAction {
public CalculateAction(String text, int keyCode) {
super(text);
putValue(MNEMONIC_KEY, keyCode);
}
@Override
public void actionPerformed(ActionEvent evt) {
try {
double[] numbers = new double[numberFields.length];
for (int i = 0; i < numbers.length; i++) {
numbers[i] = Double.parseDouble(numberFields[i].getText());
}
model.setNumbers(numbers);
} catch (NumberFormatException e) {
e.printStackTrace();
}
}
}
private class ClearAction extends AbstractAction {
public ClearAction(String text, int keyCode) {
super(text);
putValue(MNEMONIC_KEY, keyCode); // to allow buttons a mnemonic letter
}
@Override
public void actionPerformed(ActionEvent evt) {
model.clear();
}
}
}
class Model {
public static final String NUMBERS_CHANGED = "numbers changed";
private double[] numbers;
private SwingPropertyChangeSupport propChngSupport =
new SwingPropertyChangeSupport(this);
public Model(int length) {
numbers = new double[length];
}
public void setNumbers(double[] numbers) {
double[] oldValue = this.numbers;
double[] newValue = numbers;
this.numbers = numbers;
propChngSupport.firePropertyChange(NUMBERS_CHANGED, oldValue , newValue);
}
public double calculateSum() {
double sum = 0.0;
for (double number : numbers) {
sum += number;
}
return sum;
}
public double getNumber(int i) {
return numbers[i];
}
public int getNumberFieldsLength() {
return numbers.length;
}
public void clear() {
double[] newNumbers = new double[numbers.length];
setNumbers(newNumbers);
}
public void addPropertyChangeListener(PropertyChangeListener listener) {
propChngSupport.addPropertyChangeListener(listener);
}
public void removePropertyChangeListener(PropertyChangeListener listener) {
propChngSupport.removePropertyChangeListener(listener);
}
}