绘制多个圈子Android

Question

我一直试图在Android中绘制多个圈子，但它不会工作，我看不出我做错了什么。当我运行它时，一个圆圈工作得很好。我试图找到类似的问题，但我发现的问题似乎比我想要的这个简单的应用程序更先进一些。

public class DrawCharsActivity extends Activity { 

    Paint[] paint; 
    double lon = 30; 
    double lat = 20; 
    int scrWidth; 
    int scrHeight; 
    int x; 
    int y; 
    //String latitudeString[] = new String[]{"30", "20"}; 
    //String longitudeString[]= new String[]{"30", "20"}; 
    String name[] = new String[]{"joseph", "jj"}; 
    Double longitude[] = new Double[]{30.2, 30.2}; 
    Double latitude[] =new Double[]{30.2, 45.2}; 
    @Override 
    public void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 

     requestWindowFeature(Window.FEATURE_NO_TITLE); 

     setContentView(new Panel(this)); 


     // x = (int) ((scrWidth/360.0) * (180 + lon)); 
     //y = (int) ((scrHeight/180.0) * (90 - lat)); 

     scrWidth = getWindowManager().getDefaultDisplay().getWidth(); 
     scrHeight = getWindowManager().getDefaultDisplay().getHeight(); 
    } 

    class Panel extends View { 

     public Panel(Context context) { 
      super(context); 
     } 

     @Override 
     public void onDraw(Canvas canvas) { 
      for (int i = 0; i < name.length; i++) { 
       paint = new Paint[i]; 
       paint[i].setColor(Color.BLACK); 
       paint[i].setStrokeWidth(1); 
       paint[i].setTextSize(20); 

       //longitude[i] = Double.parseDouble(latitudeString[i]); 
       //latitude[i] = Double.parseDouble(longitudeString[i]); 
       x = (int) ((scrWidth/360.0) * (180 + longitude[i])); 
       y = (int) ((scrHeight/180.0) * (90 - latitude[i])); 

       canvas.drawColor(Color.WHITE); 
       canvas.drawCircle(x, y, 3, paint[i]); 

       System.out.println(x + "x" + name[i]); 
       System.out.println(y + "y" + name[i]); 

      } 


      // canvas.drawLine(80, 80, 80, 200, paint); 
      // canvas.drawText(""+canvas.getWidth()+", "+canvas.getHeight(), 0, 
      // 200,paint); 
     } 
    } 

} 

Answer 1

我解决了这个问题，我设置类面板面板面板在我DrawCharsActivity。然后，而不是写：

setContentView(new Panel(this)); 

我写道：

panel = new Panel(this); 
panel.setBackgroundColor(Color.WHITE); 
setContentView(panel); 

Answer 2

这个怎么样：

// Create an array list 
     ArrayList name = new ArrayList(); 
     // add elements to the array list 
     name.add("Joseph"); 
     name.add("jj"); 
for (String s : name) { 
paint = new Paint[i]; 
paint[i].setColor(Color.BLACK); 
paint[i].setStrokeWidth(1); 
paint[i].setTextSize(20); 

     //longitude[i] = Double.parseDouble(latitudeString[i]); 
     //latitude[i] = Double.parseDouble(longitudeString[i]); 
     x = (int) ((scrWidth/360.0) * (180 + longitude[i])); 
     y = (int) ((scrHeight/180.0) * (90 - latitude[i])); 

     canvas.drawColor(Color.WHITE); 
     canvas.drawCircle(x, y, 3, paint[i]); 

    System.out.println(x + "x" + name[i]); 
    System.out.println(y + "y" + name[i]); 

}