recover Map extent when re-mapping

[kongdd]

In this example,

shiny_rgee_template/app.R

Lines 32 to 46 in 1f43b67

	ui <- fluidPage(
	leafletOutput("mymap"),
	p(),
	actionButton("recalc", "Add SRTM Global Map")
	)
	server <- function(input, output, session) {
	dem_map <- eventReactive(input$recalc, {
	Map$addLayer(ee$Image('srtm90_v4'), list(min = 0, max = 1000))
	}, ignoreNULL = FALSE)
	output$mymap <- renderLeaflet({
	dem_map()
	})
	}
	shinyApp(ui = ui, server = server)

.

When clicking the recal button, Map extent will be automatically zoom to global scale. Any idea how to recover Map extent when re-mapping?

Thank you.