touch property

Member of

<computer>

Syntax

computer.name.touch

Read Only

Type

boolean

Remarks

It returns 1 (=touchscreen detected) or 0 (= no touchscreen detected).

This property is useful in case instructions should be adapted for touchscreen use or to terminate scripts on non-touch screens that require touch input.

Examples

The following displays if the script is run on a touch device':

<text myText>
/ items= ("touch = <% computer.touch %>")
</text>

The following displays if the script is run on a touch device in an instruction page:

<page myPage>
touch = <% computer.touch %>
</page>

The following expression adapts some instruction text based on whether the script is run on a touchscreen.

<expressions>
/ instructText = {
  if (computer.touch){
    return "touch the button with your finger";
  } else {
    return "click the button with your mouse";
  }
}
</expressions>

The following trial terminates a script if no touchscreen is detected at the end of the trial. Note that the termination trial is skipped for touchscreens.

<trial touchScreenCheck>
/ skip = {
  return (computer.touch); //script only terminates if 'computer.touch' returns 0 (false)
}
/ stimulusFrames = [1 = goodbye]
/ timeout = 1000
/ onTrialEnd = {
  script.abort();
}
</trial>