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rkeyboardmouserjava

Can I control the mouse cursor from within R?

Is it possible, to control the mouse pointer from the R console?

I have something like this in mind:

move_mouse(x_pos=100,y_pos=200)   # move the mouse pointer to position (100,200)
mouse_left_button_down            # simulate a press of the left button
move_mouse(x_pos=120,y_pos=250)   # move mouse to select something
mouse_release_left_button          # release the pressed button

In MATLAB, something like this is possible with the following code

import java.awt.Robot;
mouse = Robot;
mouse.mouseMove(0, 0);
mouse.mouseMove(100, 200);

I tried a direct conversion of the above into R that looks like this:

install.packages("rJava")          # install package
library(rJava)                     # load package
.jinit()                           # this starts the JVM
jRobot <- .jnew("java/awt/Robot")  # Create object of the Robot class

Once I got jRobot in R, I tried to call its metho "MouseMove(100,200)" using the two command below which both resulted in an error.

jRobot$mouseMove(10,10)

Error in .jcall("RJavaTools", "Ljava/lang/Object;", "invokeMethod", cl,  : 
              java.lang.NoSuchMethodException: No suitable method for the given parameters

or 

.jcall(jRobot,, "mouseMove",10,10)
Error in .jcall(jRobot, , "mouseMove", 10, 10) : 
              method mouseMove with signature (DD)V not found
Solution

  • Finally I found the problem. You have to tell R that 100 is an integer, in order to pass it to java correctly.

    install.packages("rJava")          # install package
library(rJava)                     # load package
.jinit()                           # this starts the JVM
jRobot <- .jnew("java/awt/Robot")  # Create object of the Robot class

# Let java sleep 500 millis between the simulated mouse events
.jcall(jRobot,, "setAutoDelay",as.integer(500))

# move mouse to 100,200 and select the text up to (100,300)         
.jcall(jRobot,, "mouseMove",as.integer(100),as.integer(200))
.jcall(jRobot,, "mousePress",as.integer(16))
.jcall(jRobot,, "mouseMove",as.integer(100),as.integer(300))
.jcall(jRobot,, "mouseRelease",as.integer(16))