点击计数按钮

我想统计使用GUI点击按钮的次数。点击计数按钮

我这样做代码：

private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) 
{           
    int clicked = 0; 
    clicked++; 
    System.out.println(clicked); 
}

但它显示输出“1”，每次我点击按钮。

我希望每次点击按钮向我显示计数。例如：如果我点击按钮两次，它应该给我输出“2”。

来源

2013-02-21 sofian

由于您已在动作方法内定义了变量，因此每次单击时都会重置计数器。尽量不要这样做。

int clicked = 0; // move this outside 
private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) 
{           
    // int clicked = 0; -- this resets it to 0 each time 
    clicked++; 
    System.out.println(clicked); 
}

来源

2013-02-21 10:05:01 Maccath

变化

int clicked = 0;

是你的类的成员。这样，每次按下按钮时都不会设置为零。

来源

2013-02-21 10:05:26 BobTheBuilder

您已经声明clicked作为一个局部变量，初始化为0，它永远是任何东西，但1

让clicked类级别的变量，而不是...

private int clicked = 0; 

//... 

private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) 
{           
    clicked++; 
    System.out.println(clicked); 
}

来源

2013-02-21 10:06:03 MadProgrammer

试试下面的代码

int clicked = 0; 
private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) 
{           

    clicked++; 
    System.out.println(clicked); 
}

来源

2013-02-21 10:06:07

您已在中声明count变量。在块外声明它。

int clicked = 0; //make it as your class member. 
private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) 
{           

    clicked++; 
    System.out.println(clicked); 
}

来源

2013-02-21 10:06:23 kaysush

取决于你如何实例化这个类，你需要在任现场级或类变量级别声明clicked变量。目前，clicked变量的范围是该方法的本地范围。

选项1

int clicked = 0; 

private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) 
{           
    clicked++; 
    System.out.println(clicked); 
}

选项2

static int clicked = 0; 

private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) 
{           
    clicked++; 
    System.out.println(clicked); 
}

使用将取决于实例的选项。如果可能的话，应该避免第二种选择。

每次 jButton1ActionPerformed火灾

来源

2013-02-21 10:06:33

，被点击的变量被实例化回0，这就是为什么它总是给你的值为1。你应该将这种方法

//Somewhere in your class 
private intClicked = 0; 
//More methods here. 

private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) 
{           
    clicked++; 
    System.out.println(clicked); 
}

来源

2013-02-21 10:38:58 KyelJmD

import java.awt.BorderLayout; 
import java.awt.EventQueue; 

import javax.swing.JFrame; 
import javax.swing.JPanel; 
import javax.swing.border.EmptyBorder; 
import javax.swing.JTextField; 
import javax.swing.JButton; 
import java.awt.event.ActionListener; 
import java.awt.event.ActionEvent; 


public class Threading extends JFrame { 

    private JPanel contentPane; 
    private JTextField DisplayOne; 
    private JTextField DisplayTwo; 

    int count; 
    int count1; 
    int count2; 


    /** 
    * Launch the application. 
    */ 

    public static void main(String[] args) { 
     EventQueue.invokeLater(new Runnable() { 
      public void run() 
      { 
        try { 
        Threading frame = new Threading(); 
        frame.setVisible(true); 
       } catch (Exception e) { 
        e.printStackTrace(); 
       } 
      } 
     }); 
    } 

    /** 
    * Create the frame. 
    */ 


    public Threading() 
    { 
     setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 
     setBounds(100, 100, 450, 300); 
     contentPane = new JPanel(); 
     contentPane.setBorder(new EmptyBorder(5, 5, 5, 5)); 
     contentPane.setLayout(new BorderLayout(0, 0)); 
     setContentPane(contentPane); 

     JPanel panel = new JPanel(); 
     contentPane.add(panel, BorderLayout.CENTER); 

     DisplayOne = new JTextField(); 
     panel.add(DisplayOne); 
     DisplayOne.setColumns(10); 

     DisplayTwo = new JTextField(); 
     panel.add(DisplayTwo); 
     DisplayTwo.setColumns(10); 

     JButton btnCountOne = new JButton("Count 1"); 
     count1=0; 
     btnCountOne.addActionListener(new ActionListener() {     
       public void actionPerformed(ActionEvent arg0) 
       { 
        DisplayOne.setText(Integer.toString(count1++)); 
       } 
     }); 
     panel.add(btnCountOne); 

     JButton btnCountTwo = new JButton("Count 2"); 
     count2=0; 
     btnCountTwo.addActionListener(new ActionListener() { 
      public void actionPerformed(ActionEvent arg0) 
      { 
       DisplayTwo.setText(Integer.toString(count2++)); 
      } 
     }); 
     panel.add(btnCountTwo); 

     JButton btnCountBoth = new JButton("Count Both"); 
     count=0; 
     btnCountBoth.addActionListener(new ActionListener() { 
      public void actionPerformed(ActionEvent arg0) 
      { 
       while (count < 10) 
       { 
       DisplayOne.setText(Integer.toString(++count)); 
       DisplayTwo.setText(Integer.toString(count)); 
       } 
      } 
     }); 
     panel.add(btnCountBoth); 
    } 

}

的 clicked变量外

来源

2013-03-16 07:33:41 user2176458

点击计数按钮

回答

相关问题