java - 从子类到父类(super class)获取浮点属性

Question

我正在创建一个类似于学校应用程序的绘画项目，在我当前的代码中，我有几个子类和一个 super 类。 super 应该保存要绘制的形状的数组，每个形状对象应该是它自己的子类，我稍后必须将其放入数组中并从应用程序调用。我必须使用 JDesktopPane 和 JInternalFrame，我不能使用 Arraylists，而且我目前一直在尝试将 RectDraw 子类的 Float 转换为我的 super 。所有这一切，最后将这些工具嵌套在一个名为 MyShapes 的 super 文件夹中。欢迎任何帮助。我不太使用 jdesktopPane 并且我不擅长转换。

        public class myShapes {

            public void paint(Graphics g) {

                graphSettings = (Graphics2D)g;
                graphSettings.setRenderingHint(RenderingHints.KEY_ANTIALIASING,RenderingHints.VALUE_ANTIALIAS_ON);
                graphSettings.setStroke(new BasicStroke(4));

                Iterator<Color> strokeCounter = shapeStroke.iterator();
                Iterator<Color> fillCounter = shapeFill.iterator();
                Iterator<Float> transCounter = transPercent.iterator();

                for (Shape s : shapes){
                    graphSettings.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_OVER, transCounter.next()));
                    graphSettings.setPaint(strokeCounter.next());
                    graphSettings.draw(s);
                    graphSettings.setPaint(fillCounter.next());
                    graphSettings.fill(s);
                    }


                if (drawStart != null && drawEnd != null){

                    graphSettings.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_OVER, 0.40f));
                    graphSettings.setPaint(Color.LIGHT_GRAY);

                    Shape aShape = null;                            

                    if (currentAction == 2){                            
                        RectDraw drawRectangle = new RectDraw();
                        aShape = drawRectangle(x1, y1, x2, y2);                     
                    } 
                    else if (currentAction == 3){                           
                        CircleDraw drawEllipse = new CircleDraw();
                        aShape = drawEllipse(x1, y1, x2, y2);
                    } 
                    else if (currentAction == 4) {
                        LineDraw drawLine = new LineDraw();
                        aShape = drawLine(x1, y1, x2, y2);
                    }

                    graphSettings.draw(aShape);
                    }
                }
            }

这些是我的子类

package mainPackage;

import java.awt.geom.Rectangle2D;

public class RectDraw extends myShapes {

public Rectangle2D.Float drawRectangle(int x1, int y1, int x2, int y2) {

    int RDx, RDy, RDwidth, RDheight;

    RDx = Math.min(x1, x2);
    RDy = Math.min(y1, y2);
    RDwidth = Math.abs(x1 - x2);
    RDheight = Math.abs(y1 - y2);

    return new Rectangle2D.Float(RDx, RDy, RDwidth, RDheight);
}
}

除了名称之外，其他完全相同

public class CircleDraw extends myShapes {

public Ellipse2D.Float drawEllipse(int x1, int y1, int x2, int y2){

     int x = Math.min(x1, x2);
     int y = Math.min(y1, y2);
     int width = Math.abs(x1 - x2);
     int height = Math.abs(y1 - y2);

     return new Ellipse2D.Float(x, y, width, height);
 }
}


public class LineDraw extends myShapes {

    public Line2D.Float drawLine(int x1, int y1, int x2, int y2) {

        return new Line2D.Float(x1, y1, x2, y2);
    }
}

我一直收到无法解析为变量

Answer 1

  RectDraw drawRectangle = new RectDraw();
  aShape = drawRectangle(x1, y1, x2, y2);

基于第一行的drawRectangle是RectDraw的一个实例；

在第二行中，您将引用名称“drawRectangle”与 RectDraw 类中的同名方法混淆了

您必须使用 RectDraw 类的实例调用该方法，如下所示。为了清楚起见，更改实例名称

  RectDraw rectDraw = new RectDraw();
  aShape = rectDraw.drawRectangle(x1, y1, x2, y2); 

所有形状都有同样的问题..

此外，您还在循环中创建大量实例，这不是一个好的做法。

您的问题太困惑，请在提问时尽可能清楚地说明:- https://stackoverflow.com/help/how-to-ask :)