selectMap function

Interactively Select Map Features

selectMap(x, ...)

## S3 method for class 'leaflet'
selectMap(
  x = NULL,
  styleFalse = list(fillOpacity = 0.2, weight = 1, opacity = 0.4),
  styleTrue = list(fillOpacity = 0.7, weight = 3, opacity = 0.7),
  ns = "mapedit-select",
  viewer = shiny::paneViewer(),
  title = "Select features",
  ...
)

Arguments

• x: leaflet or mapview map to use for selection

• ...: other arguments

• styleFalse, styleTrue: names list of CSS styles used for selected (styleTrue) and deselected (styleFalse)

• ns: string name for the Shiny namespace to use. The ns

  is unlikely to require a change.

• viewer: function for the viewer. See Shiny viewer. NOTE: when using browserViewer(browser = getOption("browser")) to open the app in the default browser, the browser window will automatically close when closing the app (by pressing "done" or "cancel") in most browsers. Firefox is an exception. See Details for instructions on how to enable this behaviour in Firefox.

• title: string to customize the title of the UI window. The default is "Select features".

Details

When setting viewer = browserViewer(browser = getOption("browser")) and the systems default browser is Firefox, the browser window will likely not automatically close when the app is closed (by pressing "done" or "cancel"). To enable automatic closing of tabs/windows in Firefox try the following:

• input "about:config " to your firefox address bar and hit enter
• make sure your "dom.allow_scripts_to_close_windows" is true

Examples

## Not run:

library(mapedit)
library(mapview)

lf <- mapview()

# draw some polygons that we will select later
drawing <- lf %>%
  editMap()

# little easier now with sf
mapview(drawing$finished)

# especially easy with selectFeatures
selectFeatures(drawing$finished)

# use @bhaskarvk USA Albers with leaflet code
#  https://bhaskarvk.github.io/leaflet/examples/proj4Leaflet.html
#devtools::install_github("hrbrmstr/albersusa")
library(albersusa)
library(sf)
library(leaflet)
library(mapedit)

spdf <- usa_sf()
pal <- colorNumeric(
  palette = "Blues",
  domain = spdf$pop_2014
)

bounds <- c(-125, 24 ,-75, 45)

(lf <- leaflet(
  options=
    leafletOptions(
      worldCopyJump = FALSE,
      crs=leafletCRS(
        crsClass="L.Proj.CRS",
        code='EPSG:2163',
        proj4def=paste0(
          '+proj=laea +lat_0=45 +lon_0=-100 +x_0=0 +y_0=0 +a=6370997 ',
          '+b=6370997 +units=m +no_defs'
        ),
        resolutions = c(65536, 32768, 16384, 8192, 4096, 2048,1024, 512, 256, 128)
      )
    )
  ) %>%
  fitBounds(bounds[1], bounds[2], bounds[3], bounds[4]) %>%
  setMaxBounds(bounds[1], bounds[2], bounds[3], bounds[4]) %>%
  mapview::addFeatures(
    data=spdf, weight = 1, color = "#000000",
    # adding group necessary for identification
    layerId = ~iso_3166_2,
    fillColor=~pal(pop_2014),
    fillOpacity=0.7,
    label=~stringr::str_c(name,' ', format(pop_2014, big.mark=",")),
    labelOptions= labelOptions(direction = 'auto')
  )
)

# test out selectMap with albers example
selectMap(
  lf,
  styleFalse = list(weight = 1),
  styleTrue = list(weight = 4)
)
## End(Not run)