android简单自定义view

将按钮绘制成圆形

class MyButton extends Button {

        // 这个是继承必须写的,带参构造器，所以要重写
        public MyButton(Context context) {
            super(context);
            // TODO Auto-generated constructor stub
        }

        // 在按钮中画图
        @Override
        protected void onDraw(Canvas canvas) {
            // TODO Auto-generated method stub
            super.onDraw(canvas);
            // 画笔
            Paint paint = new Paint();
            paint.setColor(Color.GREEN);
            canvas.drawCircle(30, 30, 30, paint);
        }

    }

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        MyButton my = new MyButton(this);
        LinearLayout lay = new LinearLayout(this);
        lay.addView(my);
        setContentView(lay);

    }

使用画图写游戏的建议继承View

class GameView extends View {

        private Paint paint = null;

        public GameView(Context context) {
            super(context);
            paint = new Paint();
        }

        @Override
        protected void onDraw(Canvas canvas) {
            // TODO Auto-generated method stub
            super.onDraw(canvas);
            paint.setColor(Color.RED);
            paint.setStrokeWidth(5);//画笔粗
            canvas.drawLine(0, 0, 100, 111, paint);

        }

    }

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        GameView my = new GameView(this);
        LinearLayout lay = new LinearLayout(this);
        lay.addView(my);
        setContentView(lay);

    }