如果我有两个viewControllers：oldVC和newVC，当我执行'oldVC.navigationcontroller pushviewcontroller：newVC'
viewController转换系统中的iOS生命周期是：
ggplotly()
---
output: html_document
---
### Using ggplotly()
```{r, warning = F, message = F}
library(plotly)
library(dplyr)
gg <- mtcars %>%
ggplot(aes(wt, mpg, color = gear)) +
geom_point() +
facet_wrap(~hp)
ggplotly(gg)
```
### Using plotly_build()
```{r}
ggp_build <- plotly_build(gg)
ggp_build$layout$height = 800
ggp_build$layout$width = 600
ggp_build
```
newVC ViewWillAppear
oldVC ViewWillDisAppear
但是当我将ViewControllers添加到parentViewController的scrollView（sv）中时，生命周期错过了：
newVC ViewDidAppear
oldVC ViewDidDisappear
newVC ViewWillAppear
newVC ViewDidAppear
因为我oldVC ViewWillDisAppear
如何保持正确的生命周期