Add keyboard shortcuts

Closes #13
Closes #64

Author: nathancday

R/shiny-server.R

@@ -30,6 +30,7 @@ vdiffrServer <- function(cases) {
     output$case_context <- renderCaseContext(input, cases)
 
     toggleValidateBtns(input, session)
+    listenToKeys(input, session, cases)
 
     quitApp(input)
   })
@@ -49,8 +50,9 @@ prettify_types <- function(x) {
 renderTypeInput <- function(input, reactive_cases) {
   shiny::renderUI({
     cases <- reactive_cases$all
-
+    
     types <- unique(map_chr(cases, function(case) class(case)[[1]]))
+    
     if (length(types) == 0) {
       return(NULL)
     }
@@ -152,34 +154,33 @@ withdraw_cases <- function(cases) {
 }
 
 validateSingleCase <- function(input, reactive_cases) {
-  shiny::observe({
-    if (input$case_validation_button > 0) {
-      cases <- shiny::isolate(reactive_cases$all)
-      case <- shiny::isolate(input$case)
+  shiny::observeEvent(c(input$case_validation_button, input[["validateCase"]]), {
+    
+    cases <- shiny::isolate(reactive_cases$all)
+    case <- shiny::isolate(input$case)
+    shiny::req(input$case)
 
-      withdraw_cases(cases[case])
-      cases[[case]] <- success_case(cases[[case]])
+    withdraw_cases(cases[case])
+    cases[[case]] <- success_case(cases[[case]])
 
-      shiny::isolate(reactive_cases$all <- cases)
-    }
-  })
+    shiny::isolate(reactive_cases$all <- cases)
+    })
 }
 
-validateGroupCases <- function(input, reactive_cases) {
-  shiny::observe({
-    if (input$group_validation_button > 0) {
-      active_cases <- shiny::isolate(reactive_cases$active())
-      cases <- shiny::isolate(reactive_cases$all)
-
-      if (length(cases) > 0) {
-        type <- shiny::isolate(input$type)
+validateGroupCases <- function(input, reactive_cases, session) {
+  shiny::observeEvent(c(input$group_validation_button, input[["validateGroup"]]), {
+    active_cases <- shiny::isolate(reactive_cases$active())
+    cases <- shiny::isolate(reactive_cases$all)
+    
+    if (length(cases) > 0) {
+      shiny::req(input$type)
+      type <- shiny::isolate(input$type)
 
-        withdraw_cases(active_cases)
-        idx <- sapply(cases, inherits, type)
-        cases[idx] <- lapply(cases[idx], success_case)
+      withdraw_cases(active_cases)
+      idx <- sapply(cases, inherits, type)
+      cases[idx] <- lapply(cases[idx], success_case)
 
-        shiny::isolate(reactive_cases$all <- cases)
-      }
+      shiny::isolate(reactive_cases$all <- cases)
     }
   })
 }
@@ -230,6 +231,29 @@ toggleValidateBtns <- function(input, session) {
   })
 }
 
+listenToKeys <- function(input, session, reactive_cases) {
+  shiny::observeEvent(input[["nextCase"]], {
+    names <- unique(names(reactive_cases$active()))
+    shiny::updateSelectInput(session, "case",
+                      selected = next_element(input$case, names))
+  })
+  shiny::observeEvent(input[["prevCase"]], {
+    names <- unique(names(reactive_cases$active()))
+    shiny::updateSelectInput(session, "case",
+                      selected = next_element(input$case, names, direction = -1))
+  })
+  shiny::observeEvent(input[["nextType"]], {
+    types <- unique(map_chr(reactive_cases$all, function(case) class(case)[[1]]))
+    shiny::updateSelectInput(session, "type",
+                      selected = next_element(input$type, types))
+  })
+  shiny::observeEvent(input[["prevType"]], {
+    types <- unique(map_chr(reactive_cases$all, function(case) class(case)[[1]]))
+    shiny::updateSelectInput(session, "type",
+                      selected = next_element(input$type, types, direction = -1))
+  })
+}
+
 quitApp <- function(input) {
   shiny::observe({
     if (input$quit_button > 0) {

R/utils.R

@@ -187,3 +187,17 @@ is_ci <- function() {
 is_bool <- function(x) {
   is_logical(x, n = 1) && !is.na(x)
 }
+
+next_element <- function(element, group, direction = 1) {
+  if (element == "") {
+    return(NULL) # if a type is empty
+  } else {
+    next_position <- match(element, group) + direction
+    if (next_position > length(group)) {
+      next_position <- next_position - length(group)
+    } else if (next_position < 1) {
+      next_position <- length(group)
+    }
+    return(group[next_position])
+  }
+}

inst/www/toggle.js

@@ -13,4 +13,27 @@ Shiny.addCustomMessageHandler('toggle-validate-btns-handler', toggleBtns);
 function toggleBtns(message) {
   document.getElementById('group_validation_button').disabled = message;
   document.getElementById('case_validation_button').disabled = message;
-}
+}
+
+//Keyboard shortcuts
+document.onkeydown = function(e) {
+  if (e.shiftKey) { // using e.shiftKey && e.which == 86 simultaneously doesn't work?
+    if (e.which == 39) { // down-arrow
+      Shiny.onInputChange("nextType", Math.random());
+    } else if (e.which == 37) { //up-arrow
+      Shiny.onInputChange("prevType", Math.random());
+    } else if (e.which == 86) { // v
+      Shiny.onInputChange("validateGroup", Math.random());
+    }
+  } else {
+     if (e.which == 39) { // right-arrow
+      Shiny.onInputChange("nextCase", Math.random());
+     } else if (e.which == 37) { // left-arrow
+      Shiny.onInputChange("prevCase", Math.random());
+     } else if (e.which == 86) { // v
+      Shiny.onInputChange("validateCase", Math.random());
+    } else if (e.which == 27) { //esc, q = 81
+      Shiny.onInputChange("quit_button", Math.random());
+    }
+  }
+};