debounce static method

void Function()? debounce(
  1. Function? fn, [
  2. int delay = 1000,
  3. dynamic immediate = true
])

函数防抖

Implementation

static void Function()? debounce(Function? fn, [int delay = 1000, immediate = true]) {
  Timer? timer;
  return () {
    // 还在时间之内，抛弃上一次
    if (timer?.isActive ?? false) timer?.cancel();
    if (immediate) {
      bool callNow = (timer == null);
      timer = Timer(Duration(milliseconds: delay), () {
        timer?.cancel();
        timer = null;
      });
      if (callNow) fn!();
    } else {
      timer = Timer(Duration(milliseconds: delay), () {
        fn!();
      });
    }
  };
}