android屏幕上绘图问题，亟待高手解决！！
我现在遇到一个问题，就是当执行OnTouchEvent（）时间的move时，发现传递的点并不能全部画出来，只能画出来一个点，代码如下，亟待解决！！谢谢！！public class MyLayout extends RelativeLayout {
private Paint paint;
private float screenW,screenH;
private float cx;
private float cy;
private int radius = 32;
private float a;
private Bitmap bitmap;
public MyLayout(Context context, AttributeSet attrs) {
super(context, attrs);
// TODO Auto-generated constructor stub
setWillNotDraw(false);
bitmap = BitmapFactory.decodeResource(getResources(), R.drawable.circel);
paint = new Paint();
paint.setAntiAlias(true);
paint.setStyle(Paint.Style.STROKE);
paint.setStrokeWidth(2);
paint.setColor(Color.WHITE);
}
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
revise(); // 修正
canvas.drawBitmap(bitmap, cx, cy, paint);
Log.v("rc", "onDraw "+bitmap);
}
@Override
protected void onLayout(boolean changed, int l, int t, int r, int b) {
// TODO Auto-generated method stub
super.onLayout(changed, l, t, r, b);
screenW = r-l;
screenH = (b-t);
cx = screenW/2;
cy = screenH/2;
// Log.v("rc", "onLayout:"+cx+";"+cy);
}
private void revise() {
Log.i("rc", "cx:"+cx);
if (cx <= radius) {
cx = radius;
} else if (cx >= (screenW - 2*radius)) {
cx = screenW - 2*radius;
}
if (cy <= radius) {
cy = radius;
} else if (cy >= (screenH - 2*radius)) {
cy = screenH - 2*radius;
}
}
@Override
public boolean onTouchEvent(MotionEvent event) {
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
cy = (int) event.getX();
cy = (int) event.getY();
Log.v("rc", "cx down:"+event.getX());
postInvalidate();
break;
case MotionEvent.ACTION_MOVE:
cx = (int) event.getX();
cy = (int) event.getY();
Log.v("rc", "cx: move"+event.getX());
postInvalidate();
break;
case MotionEvent.ACTION_UP:
cx = (int) event.getX();
cy = (int) event.getY();
Log.v("rc", "cx up:"+event.getX());
postInvalidate();
break;
}
return true;
} --------------------编程问答-------------------- 在dispatchDraw（）中画 --------------------编程问答-------------------- 你这个postInvalidate();是做啥？画点？画点你要传cx，cy过去，cx,cy随时都会变，你如果没传过去，那么画的只是最新的cx,cy座标。
发完整代码上来帮你调整。 --------------------编程问答-------------------- 从onDraw来看，只画了最新的cx,cy的点，没有对以前的点进行记录 --------------------编程问答-------------------- 等于说 就花了一个点。。。
补充：移动开发 , Android
