无效视图未按预期响应

Question

我正在使用自定义imageview绘制一个矩形，并在onDraw中绘制recct。代码在这里

public class ExpandableImageView extends ImageView {
        int l = 100, t = 70, r = 150, b = 180;
        int count=0;
        int h, w;
        Rect rect;
        Paint paint;
        Canvas c;

        public ExpandableImageView(Context context, AttributeSet attrs) {
            super(context, attrs);

            // TODO Auto-generated constructor stub
        }

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

        public ExpandableImageView(Context context, AttributeSet attrs, int defStyle) {
            super(context, attrs, defStyle);
        }
    @Override
    protected void onDraw(Canvas canvas) {
        // TODO Auto-generated method stub
        super.onDraw(canvas);
        Log.i(VIEW_LOG_TAG, "Inside onDraw");
        c = canvas;
        paint = new Paint();
        paint.setColor(Color.RED);
        paint.setStrokeWidth(3);
        paint.setStyle(Style.STROKE);
        rect = new Rect(l, t, r, b);
        h = rect.height();
        w = rect.width();
        if (count == 0) {
            canvas.drawRect(rect, paint);
            count++;
        }
    }

    public int getl() {
        return l;
    }

    public int gett() {
        return t;
    }

    public int getR() {
        return r;
    }

    public int getB() {
        return b;
    }

    public void doTouchEvent(MotionEvent e) {

        l = (int) e.getX();
        t = (int) e.getY();
        Log.i(VIEW_LOG_TAG, "e.getX()" + e.getX());
        Log.i(VIEW_LOG_TAG, "e.getY()" + e.getY());
        Log.i(VIEW_LOG_TAG, "rect" + r);
    }

}

现在，当我尝试在触摸事件上再次重绘rectview时，它无法正常工作 这是我主要活动的代码

    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        this.requestWindowFeature(Window.FEATURE_NO_TITLE);
        this.getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
                WindowManager.LayoutParams.FLAG_FULLSCREEN);
        imageView = new ExpandableImageView(this);
        setContentView(R.layout.cropimage);
        paint = new Paint();
        bobj = new BaldBooth1();
        bm = BaldBooth1.bMap;
        d = new BitmapDrawable(bm);
        iv = ((ImageView) findViewById(R.id.image));
        iv.setImageDrawable(d);
        ((ImageButton) findViewById(R.id.next)).setOnClickListener(this);

    }
@Override
    public boolean onTouchEvent(MotionEvent event) {
        // TODO Auto-generated method stub
        final int action = event.getAction();
        switch (action & MotionEvent.ACTION_MASK) {

        case MotionEvent.ACTION_DOWN: {
            Log.i("", "Action Down");

            imageView.doTouchEvent(event);
            break;
        }
        case MotionEvent.ACTION_MOVE: {
            Log.i("", "Action move");
            Log.i("abc", "Top"+imageView.gett());
            Log.i("abc", "Left"+imageView.getl());
            iv.invalidate();

            break;
        }
        }
        return true;
    }

}