matchingTarget 属性
继承自
指向触发事件的元素,该事件的CSS选择器被匹配。如果这个事件未与任何事件委托相关联,访问这个值将会抛出 UnsupportedError。
实现
Element get matchingTarget {
if (_selector == null) {
throw new UnsupportedError('Cannot call matchingTarget if this Event did'
' not arise as a result of event delegation.');
}
Element? currentTarget = this.currentTarget as Element?;
Element? target = this.target as Element?;
do {
if (target!.matches(_selector!)) return target;
target = target.parent;
} while (target != null && target != currentTarget!.parent);
throw new StateError('No selector matched for populating matchedTarget.');
}