Change tklabel to file name opened by tkbutton function in R - r

I am working on creating a widget in R that can open a file and show the characteristics of that file within the same widget. I want this information to be updated automatically when loading the file. This means that I have the following function for the button that can open the file:
getfile <- function() {
name <- tclvalue(tkgetOpenFile(
filetypes = "{{raster files} {.tiff .tif .img .grd}} {{All files} *}"))
if (name == "") return;
Sys.sleep(10)
assign("Filename", name, envir = .GlobalEnv)
tclvalue(Filename) <- name
}
the function for the button that opens this file is:
button.widget <- tkbutton(tt, text = "Select File", command = getfile)
tkgrid(button.widget, pady=10, padx=10, columnspan=3)
The label is given by:
Filename <- tclVar("")
label.widget <- tklabel(tt, text=tclvalue(Filename))
tkgrid(label.widget, row=2, column=0)
However, when I create the widget everything works, Filename is changed and a file can be opened. But the text in the label is not changed. How can i fix this? Is there an event that can be run when I close the OpenFile dialog window?

Try:
tklabel (tt, textvariable=Filename)
There is this example where he configures the label as text first then reconfigures it with a textvariable. But you should be able to configure it as a textvariable initially. Caveat: I don't know R.
The alternative option is to put:
tkconfigure(label.widget,text=tclvalue(Filename))
At the end of the getfile() function.

Related

Write.csv using Action buttons

So basically I am trying to make a small setup of sorts and once a certain analysis is done, I would want to export a certain dataset generated to a predefined location and a predefined name (based on the inputs selected earlier). For this purpose, I used the action button which when clicked does this,
observeEvent(input$export_button, {
write.csv(input_dummy_data4ads,paste0("Dummy Files/",unique(input_dummy_data4ads$Dependent_Variable),"_", unique(input_dummy_data4ads$Model_Type),"_", unique(input_dummy_data4ads$AGM),".csv"),row.names = F,na="")
})
The issue here is that if I click the action button once, it generates the desired csv file and at the desired location too. But after pressing it once, it takes the value of 1 (input$export_button) so when I select a new set of inputs using the radio buttons and generate a new plot based on that (by clicking another action button), the app saves a new csv file with a new name (based on the new inputs) at the desired location. What I am trying to do is to reset the value of the action button so that the new csv file is created only when I click it every time.
I tried to understand this but could not incorporate it https://github.com/rstudio/shiny/issues/167
There are specific functions in shiny for this, use downloadButton in your ui and downloadHandler in server.
server.R:
output$export_data <- downloadHandler(
filename = function() {
paste0("Dummy Files/", unique(input_dummy_data4ads$Dependent_Variable), "_", unique(input_dummy_data4ads$Model_Type), "_", unique(input_dummy_data4ads$AGM), ".csv")
},
content = function(con) {
write.csv(input_dummy_data4ads, con, row.names = F, na = "")
}
)
ui.R:
downloadButton("export_data", "Export")

R Shiny downloadHelper multiple write.csv + file.copy

I am using Shiny to produce a data.frame which the users can download by clicking on a button:
server.R
output$downloadresults <- downloadHandler(
filename= function() {
paste(country, " - Provision report.csv", sep = "")
},
content=function(file) {
write.csv(sheet1_report,file)
}
)
When the user clicks the download button, I (simultaneously) want to copy a second file from my server to the same location to where they are downloading the data.frame.
Importantly, I am trying to avoid a secondary button.
So the idea is to add the line file.copy("C:/temp/asdf.csv", file):
output$downloadresults <- downloadHandler(
filename= function() {
paste("User_chosen_filename", sep = "")
},
content=function(file) {
write.csv(sheet1_report,file)
file.copy("C:/temp/asdf.csv", file) #NEW LINE
}
)
This is not working, R only executes the first write.csv line and ignores the file.copy.
I have tested the file.copy in isolation and it works.
What am I doing wrong?

TclTk object in R

I'm new to R (and programming in general), so apologies if this has been answered elsewhere. I was not able to find an answer via searching, but any help or direction would be great!
I'm trying to make a clickable interface in R, where I can have users click to find a file of choice that proceeds to get automatically analyzed in R.
Here's what I'm having trouble with:
require(tcltk)
getfile <- function() {name <- tclvalue(tkgetOpenFile(
filetypes = "{{CSV Files} {.csv}}"))
if (name == "") return;
datafile <- read.csv(name,header=T)
}
tt <- tktoplevel()
button.widget <- tkbutton(tt, text = "Select CSV File to be analyzed", command = getfile)
tkpack(button.widget)
# The content of the CSV file is placed in the variable 'datafile'
Yet when I try to execute it, and click on a CSV file of interest after the button pops up, nothing happens. By that I mean R gives me the error below when I type in datafile.
Error: object 'datafile' not found
Once again, any help is much appreciated. Thanks!
The top level object has an environment in which you can store things, keeping them local to the GUI. Give your callbacks that object as an argument:
# callback that reads a file and stores the DF in the env of the toplevel:
getfile <- function(tt) {name <- tclvalue(tkgetOpenFile(
filetypes = "{{CSV Files} {.csv}}"))
if (name == "") return;
tt$env$datafile <- read.csv(name,header=T)
}
# callback that does something to the data frame (should check for existence first!)
dosomething <- function(tt){
print(summary(tt$env$datafile))
}
# make a dialog with a load button and a do something button:
tt <- tktoplevel()
button.choose <- tkbutton(tt, text = "Select CSV File to be analyzed", command = function(){getfile(tt)})
tkpack(button.choose)
button.dosomething <- tkbutton(tt, text = "Do something", command = function(){dosomething(tt)})
tkpack(button.dosomething)
That should be fairly robust, although I'm not sure if there's anything already in the environment that you should beware stomping on, in which case create an environment in that environment and use that for your local storage.
If you want to quit the dialog and save things for the user, prompt for a name and use assign to store them in .GlobalEnv on exit.

How to save a data frame as CSV to a user selected location using tcltk

I have a data frame called, Fail.
I would like to save Fail as a CSV in a location that the user selects. Below is some example code that I found, but I don't know how to incorporate Fail into it.
require(tcltk)
fileName <- tclvalue(tkgetSaveFile())
if (!nchar(fileName)) {
tkmessageBox(message = "No file was selected!")
} else {
tkmessageBox(message = paste("The file selected was", fileName))
}
Take a look at the write.csv or the write.table functions. You just have to supply the file name the user selects to the file parameter, and the dataframe to the x parameter:
write.csv(x=df, file="myFileName")
You need not to use even the package "tcltk". You can simply do as shown below:
write.csv(x, file = "c:\\myname\\yourfile.csv", row.names = FALSE)
Give your path inspite of "c:\myname\yourfile.csv".
write.csv([enter name of dataframe here],file = file.choose(new = T))
After running above script this window will open :
Type the new file name with extension in the File name field and click Open, it'll ask you to create a new file to which you should select Yes and the file will be created and saved in the desired location.

Interactively ask user for filename before saving file

I want to save the my tab delim files manually. I mean that I want user to choose the directory and file name when he wants to save the data. (For an example I have merged individual files into single file and want to save it.)
Usually I use write.table but in write.table we define the directory path and file name within that function but I want a function in which user can save file with any name in his desired directory.
Just use the file.choose() function,like this:
write.table(yerdata, file = file.choose(new = TRUE))
On Windows, at least, that will bring up a dialog for save-as commands.
Annoyingly the tcltk package doesn't have a function for 'Save As', it only has a file selector for choosing an existing file.
Luckily you can take the DIY approach via some tcl calls:
require(tcltk)
write.table(yerdata,file = tclvalue(tcl("tk_getSaveFile")))
The tk_choose.files function source could be used as a template to write a nicer interface to tcl("tk_getSaveFile") if needed. Does seem to be a glaring omission in package:tcltk though...
Using gWidgets:
gfile("Save yerdata", type = "save", handler = function(h, ...)
{
write.table(yerdata, file = h$file)
})
One (perhaps less than ideal) option would be to use readline to prompt the user for the full path and file name (or just the file name if you want to programmatically choose the directory) and then simply pass that value on the write.table. Here's a sketch:
FILE_PATH <- readline(prompt = "Enter a full path and file name: ")
#Some checking to make sure you got a valid file path...
write.table(yerdata, file = FILE_PATH)
Note that as per ?readline this will really only work when running R interactively.
As it is 2017 now, the tcltk2 package is an improvement of tcltk:
library(tcltk2)
filename <- tclvalue(tkgetSaveFile())
if (!nchar(filename)) {
tkmessageBox(message = "No file was selected!")
} else {
tkmessageBox(message = paste("The file selected was", filename))
}
And the use of filters, let's say one should only save as JPG/JPEG:
jpeg_filename <- tclvalue(
tkgetSaveFile(initialfile = "foo.jpg",
filetypes = "{ {JPEG Files} {.jpg .jpeg} } { {All Files} * }")
)

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