Chapter 02 section 08 updated.

Author: liuyubobobo

02-Java-Swing-Basics/08-MVC-in-Algorithm-Visualization/src/AlgoFrame.java

@@ -1,16 +1,11 @@
-import java.awt.Graphics2D;
-import java.awt.Graphics;
-import java.awt.Dimension;
-import java.awt.Color;
-import java.awt.RenderingHints;
-
 import javax.swing.*;
+import java.awt.*;
+
 
 public class AlgoFrame extends JFrame{
 
     private int canvasWidth;
     private int canvasHeight;
-    private JPanel canvas;
 
     public AlgoFrame(String title, int canvasWidth, int canvasHeight){
 
@@ -30,7 +25,6 @@ public AlgoFrame(String title, int canvasWidth, int canvasHeight){
     }
 
     public AlgoFrame(String title){
-
         this(title, 1024, 768);
     }
 
@@ -39,7 +33,7 @@ public AlgoFrame(String title){
 
     // data
     private Circle[] circles;
-    public void setCircles(Circle[] circles){
+    public void render(Circle[] circles){
         this.circles = circles;
         repaint();
     }
@@ -68,7 +62,7 @@ public void paintComponent(Graphics g) {
             AlgoVisHelper.setStrokeWidth(g2d,1);
             AlgoVisHelper.setColor(g2d, Color.RED);
             for(Circle circle: circles)
-                AlgoVisHelper.strokeCircle(g2d, circle.x, circle.y, circle.r);
+                AlgoVisHelper.strokeCircle(g2d, circle.x, circle.y, circle.getR());
         }
 
         @Override
@@ -77,5 +71,3 @@ public Dimension getPreferredSize(){
         }
     }
 }
-
-

02-Java-Swing-Basics/08-MVC-in-Algorithm-Visualization/src/AlgoVisHelper.java

@@ -7,23 +7,23 @@ public class AlgoVisHelper {
 
     private AlgoVisHelper(){}
 
-    static public void strokeCircle(Graphics2D g, int x, int y, int r){
+    public static void strokeCircle(Graphics2D g, int x, int y, int r){
 
         Ellipse2D circle = new Ellipse2D.Double(x-r, y-r, 2*r, 2*r);
         g.draw(circle);
     }
 
-    static public void fillCircle(Graphics2D g, int x, int y, int r){
+    public static void fillCircle(Graphics2D g, int x, int y, int r){
 
         Ellipse2D circle = new Ellipse2D.Double(x-r, y-r, 2*r, 2*r);
         g.fill(circle);
     }
 
-    static public void setColor(Graphics2D g, Color color){
+    public static void setColor(Graphics2D g, Color color){
         g.setColor(color);
     }
 
-    static public void setStrokeWidth(Graphics2D g, int w){
+    public static void setStrokeWidth(Graphics2D g, int w){
         int strokeWidth = w;
         g.setStroke(new BasicStroke(strokeWidth, BasicStroke.CAP_ROUND, BasicStroke.JOIN_ROUND));
     }

02-Java-Swing-Basics/08-MVC-in-Algorithm-Visualization/src/AlgoVisualizer.java

@@ -3,32 +3,37 @@
 
 public class AlgoVisualizer {
 
-    private int N;
-    private Circle[] circles;
-    static private int R = 50;
-    private AlgoFrame frame;
+    private Circle[] circles;   // 数据
+    private AlgoFrame frame;    // 视图
 
     public AlgoVisualizer(int sceneWidth, int sceneHeight, int N){
 
-        this.frame = new AlgoFrame("Welcome", sceneWidth, sceneHeight);
-
-        this.N = N;
+        // 初始化数据
         circles = new Circle[N];
-
+        int R = 50;
         for(int i = 0 ; i < N ; i ++ ) {
-            int x = (int)(Math.random()*(frame.getCanvasWidth()-2*R)) + R;
-            int y = (int)(Math.random()*(frame.getCanvasHeight()-2*R)) + R;
+            int x = (int)(Math.random()*(sceneWidth-2*R)) + R;
+            int y = (int)(Math.random()*(sceneHeight-2*R)) + R;
             int vx = (int)(Math.random()*11) - 5;
             int vy = (int)(Math.random()*11) - 5;
             circles[i] = new Circle(x, y, R, vx, vy);
         }
+
+        // 初始化视图
+        EventQueue.invokeLater(() -> {
+            frame = new AlgoFrame("Welcome", sceneWidth, sceneHeight);
+            new Thread(() -> {
+                run();
+            }).start();
+        });
     }
 
-    public void run(){
+    // 动画逻辑
+    private void run(){
 
         while(true){
             // 绘制数据
-            frame.setCircles(circles);
+            frame.render(circles);
             AlgoVisHelper.pause(20);
 
             // 更新数据
@@ -43,11 +48,6 @@ public static void main(String[] args) {
         int sceneHeight = 800;
         int N = 10;
 
-        EventQueue.invokeLater(() -> {
-            AlgoVisualizer vis = new AlgoVisualizer(sceneWidth, sceneHeight, N);
-            new Thread(() -> {
-                vis.run();
-            }).start();
-        });
+        AlgoVisualizer vis = new AlgoVisualizer(sceneWidth, sceneHeight, N);
     }
 }

02-Java-Swing-Basics/08-MVC-in-Algorithm-Visualization/src/Circle.java

@@ -1,11 +1,8 @@
-
 public class Circle {
 
-    public int x;
-    public int y;
-    public int r;
-    public int vx;
-    public int vy;
+    public int x, y;
+    private int r;
+    public int vx, vy;
 
     public Circle(int x, int y, int r, int vx, int vy){
         this.x = x;
@@ -15,6 +12,8 @@ public Circle(int x, int y, int r, int vx, int vy){
         this.vy = vy;
     }
 
+    public int getR() { return r; }
+
     public void move(int minx, int miny, int maxx, int maxy){
         x += vx;
         y += vy;