R ggvis linked_brush is not reactive - r

Question

I have the following code on my Server. R
data_agg_plot1<- reactive({
brush1 <- linked_brush(keys = data_agg()$id, "navy" )
data_agg <- data_agg()
plot1<-data_agg%>%
ggvis(x = ~dates_all) %>%
group_by(factor(dates_all.1)) %>%
layer_points(y = ~ value, fill =~dates_all.1, shape =~dates_all.1) %>%
layer_paths(y = ~ value, stroke = ~dates_all.1 , strokeOpacity := 0.5) %>%
scale_ordinal("fill", range = c("green", "red", "blue"))%>%
scale_ordinal("shape", range = c("triangle-up","triangle-down","circle")) %>%
scale_ordinal("stroke",range=c("green","red","blue")) %>%
brush1$input() %>%
hide_legend(c('stroke','fill'))%>%
add_legend(c('shape','fill'),
title = "Symbol", orient = "left",
values = c("New hires", "Attrition" , "Net Growth"),
properties = legend_props(
title = list(fontSize = 16))) %>%
add_axis("x",properties= axis_props(labels = list(angle=60,align = "left")),
tick_padding =0,
title = "") %>%
add_axis("y", title = "Total Count") %>%
set_options(width = "auto",height = 400) %>%
scale_numeric('y',clamp = TRUE)
return(list(plot1,brush1))
})
so this is a reactive function that returns me a list of 2 functions, a plot and my brush object.
the purpose of doing so is so that I can make my keys reactive - this is so that I can make an additional plot based on my user's selection. think of it as the second plot depends on what the first user highlights in the first plot.
this is my following code:
plot1_data<-reactive({
data_agg_plot1()[[1]]
})
plot1_data%>%bind_shiny("plot1")
selected_plot1 <- reactive({
data_agg_plot1()[[2]]
})
output$test <- renderPrint({
temp <- selected_plot1()$selected()
print(temp)
})
however, when I print out the selection, it is all false,
please refer to the image below:
can anybody explain to me how to overcome this?
I highly suspect I have to re-write my linkedbrush function,
I have tried both solutions from:
linked_brush in ggvis cannot work in Shiny when data change
but it does not work.