code showing that an observer that sets a reactive value, isn't invalidated by the reactive value being set elsewhere

settingReactiveValTrigger

# 
#

library(shiny)

# Define UI for application that draws a histogram
ui <- fluidPage(

    # Application title
    titlePanel("Reactive values updating"),
    actionButton("button1","button1"),
    verbatimTextOutput("button1")

)

# Define server logic required to draw a histogram
server <- function(input, output) {
    testRV <- reactiveValues()
    testRV$val1 <- 0
    output$button1 <- renderText({
        isolate({testRV$val1 <- testRV$val1 + 1})
        result_txt <- paste("button pushed ",input$button1,"val1:", isolate(testRV$val1))
        print(result_txt)   
        paste(result_txt )
    })
    observe({
        print("observer set RV fired")
        testRV$val1 <- 27 
    })
    observe({
        print(paste("observer using RV fired", testRV$val1))

    })

}

# Run the application 
shinyApp(ui = ui, server = server)