关于switchTab #53
Description
Is your feature request related to a problem? Please describe.
请求加一个 switchTab功能，比如我有一个 A1, B1, C1, D1 四个tab页面，当我进去到 A1 -> A2 -> A3 -> A4 的时候，想切换到B1或者C1，如果直接切换会导致KeepAlive还在路由栈中，求作者加一个类似小程序的switchTab
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