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这是我正在编写的代码：---

public class board extends Activity 
 {  
     Canvas canvas;Bitmap bitmap;

public void onCreate(Bundle savedInstanceState) 
{
    super.onCreate(savedInstanceState);


    DisplayMetrics metrics = getResources().getDisplayMetrics();
    int width = metrics.widthPixels;
    int height = metrics.heightPixels;
    Log.d("board", "height is" + height + "width"+ width ); 


     bitmap = Bitmap.createBitmap(width, height, Config.RGB_565);

    Paint blue = new Paint();
    Paint red = new Paint();
    Paint green = new Paint();
    Paint yellow = new Paint();

    blue.setColor(Color.BLUE);
    blue.setStrokeWidth(5);

    red.setColor(Color.RED);
    red.setStrokeWidth(5);
    green.setColor(Color.GREEN);
    green.setStrokeWidth(5);
    yellow.setColor(Color.YELLOW);
    yellow.setStrokeWidth(5);



     canvas = new Canvas(bitmap);

      canvas.drawColor(Color.BLACK);

      red.setStyle(Paint.Style.FILL);

        Path path = new Path();
        path.setFillType(FillType.EVEN_ODD);
        path.moveTo(width/5, height/3);
        path.lineTo((4*width)/5, (height)/3);
        path.moveTo((4*width)/5, (height)/3);
        path.lineTo(width/2, (17*height)/30);
        path.moveTo(width/2, (17*height)/30);
        path.lineTo(width/5, height/3);
        path.moveTo(width/5, height/3);
        path.close();
        canvas.drawPath(path, red);

    ImageView imageView = new ImageView(this);

    imageView.setImageBitmap(bitmap);

    RelativeLayout layout = new RelativeLayout(this);
    RelativeLayout.LayoutParams params = new 
        RelativeLayout.LayoutParams(LayoutParams.WRAP_CONTENT,
       LayoutParams.WRAP_CONTENT);
    params.addRule(RelativeLayout.CENTER_IN_PARENT);
    layout.addView(imageView, params);
    layout.setBackgroundColor(Color.BLACK);

    setContentView(layout);



}

必需的输出：-黑色背景上的红色实心三角形。

我得到的输出是：-仅黑色背景。

那么导致错误的多数民众赞成在代码出什么问题了。