Predefined Variables

Predefined variables are a set of variables that are always accessible in your prototypes. The values they store update automatically.

For example, the value of $mouseX will always change automatically, depending on wherever the cursor finds itself.

Learn more about using variables.

$mouseX x-coordinate of the cursor.

$mouseY y-coordinate of the cursor.

$touchX x-coordinate of where a touch is registered.

$touchY y-coordinate of where a touch is registered.

$touchVelocity Velocity of a touch using a finger or mouse that is in movement.

$touchVelocityX x-component of the velocity of a touch using a finger or mouse that is in movement.

$touchVelocityY y-component of the velocity of a touch using a finger or mouse that is in movement.

$touchPointerCount Number of fingers touching the screen.

$keyboardHeight Height of a native keyboard on a smart device when it is visible. Learn more about the input layer.

$deviceOS Operating system of the device the prototype is running on.

$pi Pi (3.141592).

$time Time (seconds) passed since the prototype started. If you want to know the time passed since a certain event, assign the time when the event occurs to a variable and deduct it from $time.

$voiceTranscript Incoming speech whenever listening to voice commands is enabled. Learn more about voice prototyping.

$deviceHeight displays the height of the device.

$deviceWidth displays the width of the device.

The device width and device height of a device represent its screen size (resolution size), not the viewport size. For example, an iPhone 14 Pro has a resolution of 390x844 @3x, so its device width x device height is 1170x2532 (i.e., (390x3)x (844x3)).

Therefore, the preset size and the device size are not related. If you run a pie that is preset to iPhone 13 on an iPhone 14, the device size of the iPhone 14 will be displayed. Check out this example to learn more.

$qrValue returns the value stored in a QR code after it has been scanned using the QR & Barcode Scanner. Learn more about the QR Code Scanner.

$qrHeight returns the height stored in a QR code after it has been scanned using the QR & Barcode Scanner. Learn more about the QR Code Scanner.

$qrWidth returns the width stored in a QR code after it has been scanned using the QR & Barcode Scanner. Learn more about the QR Code Scanner.

$qrX returns the x-coordinate stored in a QR code after it has been scanned using the QR & Barcode Scanner. Learn more about the QR Code Scanner.

$qrY returns the y-coordinate stored in a QR code after it has been scanned using the QR & Barcode Scanner. Learn more about the QR Code Scanner.

$barcodeValue returns the value stored in a barcode after it has been scanned using the QR & Barcode Scanner.

$barcodeHeight returns the height stored in a barcode after it has been scanned using the QR & Barcode Scanner.

$barcodeWidth returns the width stored in a barcode after it has been scanned using the QR & Barcode Scanner.

$barcodeX returns the x-coordinate stored in a barcode after it has been scanned using the QR & Barcode Scanner.

$barcodeY returns the y-coordinate stored in a barcode after it has been scanned using the QR & Barcode Scanner.