Question

我一直试图在Android中绘制多个圈子，但它不起作用，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在这个简单的应用程序中的要求更高级。

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 &lt; 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

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]);

}

Answer 2

我解决了这个问题，我在DrawCharsActivity中将类Panel设置为Panel面板。然后而不是写：

setContentView(new Panel(this));

我写道：

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

绘制多个Android圈子

2 个答案: