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Notice: This page contains information for the legacy Phidget21 Library.

Phidget21 is out of support. Bugfixes may be considered on a case by case basis.

Phidget21 does not support VINT Phidgets, or new USB Phidgets released after 2020. We maintain a selection of legacy devices for sale that are supported in Phidget21.

We recommend that new projects be developed against the Phidget22 Library.


Click on the 2phidget22.jpg button in the menu bar to go to the Phidget22 version of this page.

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Language - Applescript: Difference between revisions

From Phidgets Legacy Support
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By following the instructions above, you probably now have a working example and want to understand it better so you can change it to do what you want.  This teaching section has resources for you to learn from the examples and write your own.
By following the instructions above, you probably now have a working example and want to understand it better so you can change it to do what you want.  This teaching section has resources for you to learn from the examples and write your own.


Your main reference for writing AppleScript code will be our AppleScript API information, with syntax for all of our functions:
Your main reference for writing AppleScript code will be our API information, with syntax for all of our functions:


{{UsingAPhidgetInCodeGeneral|both of which are available in AppleScript|Find the API under AppleScript Editor → File → Open Dictionary → PhidgetOSA}}
{{UsingAPhidgetInCodeGeneral|both of which are available in AppleScript|'''AppleScript API''' - Find the API under AppleScript Editor → File → Open Dictionary → PhidgetOSA}}


===Code Snippets===
===Code Snippets===

Revision as of 14:25, 22 May 2012

Icon-Applescript.png Applescript is a scripting language for OS X designed primarily for interfacing between applications.


Introduction

If this is your first time working with a Phidget, we suggest starting with the Getting Started page for your specific device. This can be found in the user guide for your device. That page will walk you through installing drivers and libraries for your operating system, and will then bring you back here to use AppleScript specifically.

AppleScript is capable of using the complete Phidget API, including events. We also provide example code in AppleScript for all Phidget devices.

AppleScript can be developed with AppleScript Editor on OS X..

You can compare AppleScript with our other supported languages.

Quick Downloads

Just need the AppleScript documentation, drivers, libraries, and examples? Here they are:

Documentation

Find the API under AppleScript Editor → File → Open Dictionary → PhidgetOSA

Example Code

Libraries and Drivers

Getting started with AppleScript

If you are new to writing code for Phidgets, we recommend starting by running, then modifying existing examples. This will allow you to:

  • Make sure your libraries are properly linked
  • Go from source code to a test application as quickly as possible
  • Ensure your Phidget is hooked up properly

We offer support for developing AppleScript on OS X.

OS X

Description of Files

Preference Pane integration, etc

AppleScript Editor

The Phidget examples were written using AppleScript 2.1.2 under AppleScript Editor 2.3, and this tutorial assumes their use. Other versions and development environments (e.g. XCode, Smile) should work as well and would be set up in a similar manner.

Use Our Examples

Insert many screenshots

Write Your Own Code

To start writing your own code from scratch:

  • First, open the AppleScript editor to create a new script.
  • Coding with Phidgets is made possible by the interaction of Apple Events between AppleScript and the PhidgetsOSA application. Type the following to interact with PhidgetsOSA:
  tell application "PhidgetsOSA"
  end tell

The project now has access to Phidgets and we are ready to begin coding. All code is then typed inside this tell block.

Follow The Examples

By following the instructions above, you probably now have a working example and want to understand it better so you can change it to do what you want. This teaching section has resources for you to learn from the examples and write your own.

Your main reference for writing AppleScript code will be our API information, with syntax for all of our functions:

  • AppleScript API - Find the API under AppleScript Editor → File → Open Dictionary → PhidgetOSA (This is the complete set of functions you have available for all Phidgets)
  • Device Specific APIs - The one for your Phidget can be found in its user guide.

To learn the details behind opening, configuring, using, and closing your Phidget, try the General Phidget Programming page. That page also describes using the Phidget in an event-driven manner and in a traditional manner, both of which are available in AppleScript.

Code Snippets

Specific calls in AppleScript will differ in syntax from those on the General Phidget Programming page, but the concepts stay the same.

It may help to have the General Phidget Programming page and this section open at the same time, because they parallel each other and you can refer to the C# syntax. However, many additional concepts are covered on the General Phidget Programming page on a high level, such as using multiple Phidgets, handling errors, and different styles of programming.

Coding For Your Phidget

A Phidget object will need to be declared. For example, we can declare a PhidgetInterfaceKit:

  set ifkit to make new phidget interfacekit

The object name for any type of Phidget is listed in the PhidgetsOSA dictionary. Every type of Phidget also inherits functionality from the Phidget base class.

Connecting to the Phidget

Next, the Phidget object needs to be initialized and the program needs to try and connect to the Phidget through a call to open. Open will tell the program to continuously try to connect to a Phidget, based on the parameters given, even trying to reconnect if it gets disconnected. This means that simply calling open does not guarantee you can use the Phidget immediately. We can handle this by using event driven programming and tracking the Attach Events and Detach Events, or by specifying the wait parameter. The wait parameter will block for a certain amount of time until a connection is made to the Phidget. For example, we can connect to a PhidgetInterfaceKit with:

  tell ifkit to open

The different types of open can be used with parameters to try and get the first device it can find, open based on its serial number, or even open across the network. For more information on connecting across a network, please see the "Working with Phidget WebService" guide on the programming section at www.phidgets.com. The PhidgetsOSA dictionary lists all of the available modes that open provides. Examples of the usage of different types of open are listed below:

We can tell the ifkit to block for 5000ms until a connection has been made to the PhidgetInterfaceKit with:

  tell ifkit to open wait 1000 --wait for 5000ms

We can also connect to a PhidgetInterfaceKit over the WebService with a serial number of 99999 on a server with an IP Address of 192.168.3.180 and a port that is opened on 5001 with:

  tell ifkit to open serial number 99999 server address "192.168.3.180" server port 5001

It is also possible to connect using the server id. For example, we can connect to a PhidgetInterfaceKit on a password protected server with:

  tell ifkit to open server id "TestMac" password "pw"

At the end of your script, don’t forget to call close to free any locks on the Phidget.

  tell ifkit to close
  delete ifkit

Phidgets can also be freed from the PhidgetsOSA Menu Bar.

Event Driven Programming

We recommend the use of event driven programming when working with Phidgets. We can hook an event handler at loading with the following code:

  tell ifkit to make new interfacekit sensor change handler with properties {script file:thisScript}

And after the tell block at end of the script, the callback method is defined as follows:

  using terms from application "PhidgetsOSA"
    on interfacekit sensor changed ind to val on ifkit
      log "Sensor Index: " & ind & ", Sensor Value: " & val
    end interfacekit sensor changed
  end using terms from

With this function, the code inside the interfacekit sensor changed handler will get executed every time the PhidgetInterfaceKit reports a change on one of its analog inputs. Some events such as Attach and Detach belong to the base Phidget object and thus are common to all types of Phidgets. Please refer to the PhidgetsOSA dictionary and the AppleScript examples for a list of events and their usage.

Please keep in mind that events are triggered from the PhidgetsOSA application and not from AppleScript. Thus, the AppleScript editor won't be able to receive replies when the script runs. In addition, any changes you make to the event code must be saved in order for the changes to take effect.

Working directly with the Phidget

Some values can be read and sent directly to the Phidget. For example, sensor values from the PhidgetInterfaceKit can be read with:

  log "The first sensor has a value of: " & first interfacekit sensor's value

These functions can be used inside a polling loop as an alternative to event driven programming.

Using the same Phidget in more than one Application

One important thing to remember is that when working with Phidgets, a call to open will reserve the device until closed. This prevents any other instances from retrieving data from the Phidget, including other programs. If your goal is to use the same Phidget among multiple AppleScripts and/or other applications, there are two approaches.

1. Implement logic in the script that will use the same Phidget object if the script detects that a Phidget of the same type has already been initialized.

For example,

  if first phidget interfacekit exists then
    set ifkit to the first phidget interfacekit
  else
    set ifkit to make the phidget interfacekit
    open ifkit
  end if


2. The one connection per device limit does not apply when exclusively using the open Phidget Webservice. For more information, please see the "Connecting to the Phidgets" section of this document.

Working with multiple Phidgets

Multiple Phidgets of the same type can easily be run inside the same program. In our case, it requires another InterfaceKit instance to be defined and initialized. The new instance can then be set up, opened and used in the same process as the previous one. If the application needs to distinguish between the devices, open can be called with the serial number of a specific Phidget.

Other Phidgets

The design given in this document can also be followed for almost all Phidgets. For example, if you were using a PhidgetRFID instead of an PhidgetInterfacekit, you would declare an RFID object instead of an InterfaceKit. The methods and events available would change but they can be accessed in a similar manner.

PhidgetsOSA Menu Bar

Applescript bar.jpg

The PhidgetsOSA menu bar appears whenever AppleScript accesses the PhidgetsOSA application. The menu bar is used to monitor the status of any accessed Phidgets.

Additionally, it can be used to free the lock on a Phidget or quit the PhidgetsOSA application.

Common Problems and Solutions/Workarounds

None at this time.