compoundInput2 provides group inputs where each group
contains multiple shiny inputs. For examples
compoundInput2(
'compound', 'Group Label', label_color = 1:10,
components = div(
textInput('txt', 'Text'),
selectInput('sel', 'Select', choices = 1:10, multiple = TRUE),
sliderInput('sli', 'Slider', max=1, min=0, val=0.5)
), max_ncomp = 10, min_ncomp = 0, initial_ncomp = 1
)will create a list of input groups with minimum of 0 but maximum of
10. User can control the size of groups by pressing + and
- buttons. The value input$components looks
like this:
#> [[1]]
#> [[1]]$txt
#> [1] ""
#>
#> [[1]]$sel
#> [1] "1" "3"
#>
#> [[1]]$sli
#> [1] 0.5
#>
#> [[2]]
...
I found this input extremely useful in clinic trial when the experiment condition is grouped and developers don’t know ahead the number of condition groups.
The further details can be found with
demo('example-compountInput2', package='dipsaus'). The
source file can be found using
system.file('demo/example-compountInput2.R', package='dipsaus').
sync_shiny_inputs provides a way to update among
multiple inputs with no dead-locks. For example, input A
(textInput) shares the same information as input B
(sliderInput). Updating A would trigger B to update. What
if you want A to be updated when B is changed? The following code might
cause recursive updates:
# Bad example
observeEvent(input$A, {
updateSliderInput(session, 'B', value = input$A)
})
observeEvent(input$B, {
updateTextInput(session, 'A', value = input$B)
})In this case, you can use sync_shiny_inputs:
sync_shiny_inputs(input, session, inputIds = c('A', 'B'), uniform = list(
function(a){as.numeric(a)},
function(b){ b }
), updates = list(
function(a){updateTextInput(session, 'A', value = a)},
function(b){updateSliderInput(session, 'B', value = b)}
))inputIds refers to the input ID to be synchronized. When
one or more of the inputs are changed, the value will be passed to the
corresponding uniform functions and stored, then
updates will notify each inputs to update the UI values.
The input of updates is the stored value.
For example, if input A is changed from "0"
to "1", then the first function of uniform is
triggered, function(a){as.numeric(a)} will be evaluated
with a="1". The result, which is numeric 1
will be stored. Next, each functions in updates will be
called, with 1 (stored in the previous step) as input,
results in changing the slider input B to 1.
This whole process will not trigger A to re-update.