使用绘图代理在不改变标记大小的情况下以图形方式更改迹线标记的颜色

Question

我正在尝试使用plotlyproxy来改变color的trace，这有效，但问题是，它也改变了我的标记/ legendmarkers的大小。

很久以前我发现（据我目前的研究表明）仍无法单独设置图例标记的大小与图标记不同。

如果你想要在散点图中绘制5000点，如果你问我最终得到的是小传说或巨型情节标记，那就是一场灾难。

所以问题是A或B解决方案类型：A：找到一种方法来使用plotlyproxy而不更改我的legend marker size或B：找到一种方法来分别调整legend的大小，以一种不受影响的方式，当plotlyproxy开火

我欢迎那些了解这个图例大小问题的人的任何反馈。

注意：可能这可以用javascript完成，但如果在这种情况下，我可能需要提供更多关于我正在努力实现的实际应用程序的信息

这是显示它的虚拟应用程序：

library(plotly)
library(shiny)
library(htmlwidgets)
library(colourpicker)


ui <- fluidPage(
  fluidRow(
     column(8,
           plotlyOutput("plot1")
    ),
    column(2,
                   colourpicker::colourInput(inputId = 'markercolor', label = 'X',
           palette = "limited", 
           showColour = "background", returnName = TRUE),
           selectInput(inputId = 'traceNo', label = 'Trace', choices = c(1:3), selected = 1),
           br(),
           h5('Switch'),
           actionButton(inputId = 'Switch', label = icon('refresh'), style = "color: #f7ad6e;   background-color: white;  border-color: #f7ad6e;
                        height: 40px; width: 40px; border-radius: 6px;  border-width: 2px; text-align: center;  line-height: 50%; padding: 0px; display:block; margin: 2px")
    )
  )
)

server <- function(input, output, session) {
  # values <- reactiveValues()


  observeEvent(input$Switch, { 
    plotlyProxy("plot1", session) %>%
      plotlyProxyInvoke("restyle", list(marker = list(color = input$markercolor)), list(as.numeric(input$traceNo)-1))
    })

  output$plot1 <- renderPlotly({
    markersize <- 4
    markerlegendsize <- 20
   colors <- c('red', 'blue', 'black')
    p1 <- plot_ly()
    p1 <-  add_trace(p1, data = mtcars, x = ~disp, y = ~mpg, type = 'scatter', mode = 'markers', color = ~as.factor(cyl), colors = colors)
    p1 <- layout(p1, title = 'mtcars group by cyl with switching colors')
    p1 <- plotly_build(p1)

    ## this is a bit of a hack to change the size of the legend markers to not be equal to the plot marker size. 
    ## it makes a list of 1 size value for each marker in de trace in the plot, and another half of with sizes that are a lot bigger.
    ## the legend marker size is effectively the average size of all markers of a trace
    for(i in seq(1, length(sort(unique(mtcars$cyl) )))) {
      length.group <- nrow(mtcars[which(mtcars$cyl  == sort(unique(mtcars$cyl))[i]), ])
      p1$x$data[[i]]$marker$size <- c(rep(markersize,length.group), rep(c(-markersize+2*markerlegendsize), length.group))
    }
    p1
  })
}

shinyApp(ui, server)

Answer 1

您可以使用shinyJS注入custon javascript代码。在这里，我使用一些d3来选择图例项并更改它们的大小。这是非常hacky但不幸的是，据我所知，情节上没有提供内部解决方案。

library(plotly)
library(shiny)
library(htmlwidgets)
library(colourpicker)
library(shinyjs)

jsCode <- "shinyjs.changelegend = function(){
var paths = d3.select('#plot1').
select('.legend').
select('.scrollbox').
selectAll('.traces').
select('.scatterpts')
.attr('d','M8,0A8,8 0 1,1 0,-8A8,8 0 0,1 8,0Z');}"

ui <- fluidPage(
  tags$script(src = "https://d3js.org/d3.v4.min.js"),
  useShinyjs(),
  extendShinyjs(text = jsCode),
  fluidRow(
    column(8,
           plotlyOutput("plot1")
    ),
    column(2,
           colourpicker::colourInput(inputId = 'markercolor', label = 'X',
                                     palette = "limited", 
                                     showColour = "background", returnName = TRUE),
           selectInput(inputId = 'traceNo', label = 'Trace', choices = c(1:3), selected = 1),
           br(),
           h5('Switch'),
           actionButton(inputId = 'Switch', label = icon('refresh'), style = "color: #f7ad6e;   background-color: white;  border-color: #f7ad6e;
                        height: 40px; width: 40px; border-radius: 6px;  border-width: 2px; text-align: center;  line-height: 50%; padding: 0px; display:block; margin: 2px")
           )
    ),
  tags$div(id = "test")
  )

server <- function(input, output, session) {
  # values <- reactiveValues()


  observeEvent(input$Switch, { 
    plotlyProxy("plot1", session) %>%
      plotlyProxyInvoke("restyle", list(marker = list(color = input$markercolor)), list(as.numeric(input$traceNo)-1))
  })

  observeEvent(input$Switch,{
    js$changelegend()
  })

  output$plot1 <- renderPlotly({
    markersize <- 4
    markerlegendsize <- 20
    colors <- c('red', 'blue', 'black')
    p1 <- plot_ly()
    p1 <-  add_trace(p1, data = mtcars, x = ~disp, y = ~mpg, type = 'scatter', mode = 'markers', color = ~as.factor(cyl), colors = colors)
    p1 <- layout(p1, title = 'mtcars group by cyl with switching colors')
    p1 <- plotly_build(p1)

    # this is a bit of a hack to change the size of the legend markers to not be equal to the plot marker size.
    # it makes a list of 1 size value for each marker in de trace in the plot, and another half of with sizes that are a lot bigger.
    # the legend marker size is effectively the average size of all markers of a trace
    for(i in seq(1, length(sort(unique(mtcars$cyl) )))) {
      length.group <- nrow(mtcars[which(mtcars$cyl  == sort(unique(mtcars$cyl))[i]), ])
      p1$x$data[[i]]$marker$size <- c(rep(markersize,length.group), rep(c(-markersize+2*markerlegendsize), length.group))
    }
    return(p1)
  })

}

shinyApp(ui, server)

自定义javascript代码在jsCode中定义，extendShinyjs()在js$changelegend()中初始化。最后，只要单击按钮，就会在js$changelegend()中调用它。

如果你有多个图并且你想要相同的行为，你可以将plot id作为参数传递给jsCode并相应地改变qazxswpoi来处理这个问题。