Java 编写简单的计算器（可视化）

骑猪看日落 2023-06-23 15:21 75阅读 0赞

## 编写一个简单的计算器能够计算加减乘除法 ##

运行结果：

![20191219231240803.png][]

package javafxTest;
    
    import javafx.application.Application;
    import javafx.event.ActionEvent;
    import javafx.event.EventHandler;
    import javafx.scene.Scene;
    import javafx.scene.control.*;
    import javafx.scene.image.Image;
    import javafx.scene.layout.*;
    import javafx.scene.text.Font;
    import javafx.stage.Stage;
    //import javafx.event.ActionEvent;
    //import javafx.event.EventHandler;
    
    public class Calculator extends Application {
      
      double left;
      double right;
      char op;
    
      @Override // Override the start method in the Application class
      public void start(Stage primaryStage) {
        // Create a border pane 
    	primaryStage.getIcons().add(new Image("file:F:\\预科\\timg.jpg"));//左上角的图标
        BorderPane pane = new BorderPane();
    
        // Place nodes in the pane
    
        TextField input =  new TextField();
        input.setPrefHeight(40);
        input.setFont(Font.font("",25));
        pane.setTop(input); 
    
        AnchorPane gridPane = new AnchorPane();
        
        // Place nodes in the pane
    
        Button[] buttonGroup = { 
           new Button("1") ,new Button("2"),new Button("3"),new Button("4"),
           new Button("5") ,new Button("6"),new Button("7"),new Button("8"),
           new Button("9") ,new Button("0"),new Button("."),new Button("/"),
           new Button("+") ,new Button("-"),new Button("*"),new Button("="),
           new Button("Ac"),new Button("Close")};
        
        gridPane.getChildren().addAll(buttonGroup);
        
        for(int i=0; i<buttonGroup.length; i++) //按钮大小
        {
        	buttonGroup[i].setPrefHeight(40);
        	buttonGroup[i].setPrefWidth(50);
        	buttonGroup[i].setFont(Font.font("",20)); //按钮上的文本
        	}
    
        //按钮位置
        
        buttonGroup[16].setLayoutX(20);
    	buttonGroup[16].setLayoutY(190);
    	buttonGroup[16].setPrefWidth(95);
    	
    	buttonGroup[17].setLayoutX(140);
    	buttonGroup[17].setLayoutY(190);
    	buttonGroup[17].setPrefWidth(95);
    	
    	for(int i=0;i<4;i++)
    	{
    		buttonGroup[i].setLayoutX(20+55*i+1);
    		buttonGroup[i].setLayoutY(10);
    	}
    	int j=0;
    	for(int i=4;i<8;i++)
    	{
    		
    		buttonGroup[i].setLayoutX(20+55*j+1);
    		buttonGroup[i].setLayoutY(55);
    		j++;
    	}
    	j=0;
    	for(int i=8;i<12;i++)
    	{
    		
    		buttonGroup[i].setLayoutX(20+55*j+1);
    		buttonGroup[i].setLayoutY(100);
    		j++;
    	}
    	j=0;
    	for(int i=12;i<16;i++)
    	{
    		
    		buttonGroup[i].setLayoutX(20+55*j+1);
    		buttonGroup[i].setLayoutY(145);
    		j++;
    	}
        
        
        //按钮添加单击事件 
    	for(int i=0; i<16; i++) {
               buttonGroup[i].setOnAction(e -> { 
                 Button btn = (Button) e.getSource();         
                 switch (btn.getText()) {
                     case "1":   case "2":   case "3":   case "4":   case "5":      case "6": 
                     case "7":   case "8":   case "9":   case "0":   case ".":
                         input.setText( input.getText()+ btn.getText()) ; break;
                     case "+" :   case "-" :   case "*" :  case "/" :  
                         left = Double.parseDouble(input.getText()) ;
                         op =   btn.getText().charAt(0);
                         input.setText("") ;
                         break;
                     case "=": 
                         right = Double.parseDouble(input.getText()) ;
                          switch(op) {
                              case '+' :    input.setText(Double.toString(left+right)); break;
                              case '-' :  input.setText(Double.toString(left-right)); break;
                              case '*' :   input.setText(Double.toString(left*right)); break;
                              case  '/' :  input.setText(Double.toString(left/right)); break;
                           }
                      }
                 }
                );
          }
        
    	
    	
        pane.setCenter( gridPane); 
    
        // Create a scene and place it in the stage
        Scene scene = new Scene(pane);
        primaryStage.setTitle("计算器"); // Set the stage title
        primaryStage.setScene(scene); // Place the scene in the stage
        primaryStage.setHeight(325);
        primaryStage.setWidth(265);
        primaryStage.setResizable(false);//固定窗口大小不能改变
        primaryStage.show(); // Display the stage
        
        //Ac 按键 添加清空输入框
        buttonGroup[16].setOnAction(new EventHandler<ActionEvent>() {  
    		
    		@Override
    		public void handle(ActionEvent arg0) {
    			input.setText("");
    		}
    	});
        
        //close 按钮添加关闭事件
    	buttonGroup[17].setOnAction(new EventHandler<ActionEvent>() {
    			
    			@Override
    			public void handle(ActionEvent arg0) {
    				primaryStage.close();
    			}
    		});
        
        
      }
      
      public static void main(String[] args)
      {
    	  launch(args);
      }
    }

备注：代码里有很多可以优化的地方

[20191219231240803.png]: https://img-blog.csdnimg.cn/20191219231240803.png