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== Introduction ==
[[Category:Language]]
__NOTOC__


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 Swift specifically.
We provide support for the Swift language on macOS. We also provide instructions on how to get your project started in Xcode for use in '''macOS''' and '''iOS''' applications. Select your operating system below, and follow the instructions to get your project running with Phidgets.
Swift is capable of using the complete {{Phidget22API}}, including events.


Swift is capable of using the complete Phidget API, including events. When using it on iOS devices, however,  Phidgets can only be remotely controlled over a network using the [[Phidget Network Service]] because they don't support direct USB connection.
Once you have set up your development environment to run with Phidgets, we recommend you follow our guide on [[Phidget Programming Basics]]. The guide will showcase the fundamentals of programming with Phidgets.


Swift can be developed with Xcode on macOS.
==Setup Guide==


== Quick Downloads ==
<div class="phd-deck-sequence">
  __NOTOC__
{{PT3_SWIFT_CHOOSE}}{{PT3_SWIFT_MAC_XCODE}}{{PT3_SWIFT_MAC_XCODE_1}}{{PT3_SWIFT_MAC_XCODE_2}}{{PT3_SWIFT_IOS_XCODE}}{{PT3_SWIFT_IOS_XCODE_1}}{{PT3_SWIFT_IOS_XCODE_2}}
</div>


'''<span style="color:#FF0000">List of download links, to be added once files are available</span>'''


== Getting Started with Swift ==
== Quick Downloads ==
== iOS ==
===Xcode===
====Use our examples====
If Xcode is not already installed on your system, then you will need to install it. You can download it for free from the Mac app store.


Start by ensuring the [[Phidget Network Service]] is running on the computer that the Phidget is physically plugged in and connected to.  This computer needs to have a USB port and should be running macOS or one of our other supported [[Operating System Support|operating systems]]. For directions on how to set up and run the [[Phidget Network Service]] refer to the page for that operating system.
If you already know what you're doing and just need the files, you can find them all below.


Then, on the macOS system that will be used for developing the iOS application, download and unpack the '''<span style="color:#FF0000">Phidget Examples for Swift</span>'''. The easiest way to confirm that your environment is set up is to compile and the Phidgets app. Start by opening the Phidgets.xcodeproj in Xcode.
=== Documentation ===


Next, select the target you want the application to run on. In order to run the example on a physical device, you must be an '''<span style="color:#FF0000">Apple Developer</span>''', otherwise you can choose to run the example on a simulator.
*{{Phidget22API}}  (select Swift from the drop-down menu)


[[Image:ios_SelectTarget.png]]
=== Example Code ===


To run the example, click on the Run button.
*{{SampleCode|Swift|Swift Examples}}


[[Image:ios_RuniOS.png]]
===Libraries===


The program will detect any servers that are currently online and have Phidgets connected. Here is an example output:
{{AllQuickDownloads}}
 
[[Image:ios_PhidgetApp_MainScreen.png | 500px]]
 
After confirming that the Phidgets Example is working, you can proceed to run the example for your specific device. Do this by continuing to navigate through the hierarchy until you reach your device, after tapping your device the example will show automatically. Currently, we have example programs for the following software objects:
 
* DigitalInput
 
* DigitalOutput
 
* VoltageInput
 
* VoltageRatioInput
 
Here is an example of what the DigitalOutput example looks like:
 
[[Image:ios_PhidgetApp_DigitalOutput.png | 500px]]
 
Once you have the Swift example running, we have a [[#Editing the Code|teaching]] section below to help you follow them.
 
====Write your own code====
 
Whether you are  building a project from scratch, or adding Phidget functionality to an existing project, you will need to configure your development environment to properly link the Phidget library. To begin:
 
1. Create a new Xcode project
 
[[Image:Cocoa_CreateProject.png | 500px]]
 
2. Select an iOS application. For this tutorial's purposes, we will use a Single View Application.
 
[[Image:iOS_SingleView.png | 500px]]
 
3. Give the project a descriptive name such as PhidgetTest, select Objective-C as the language, and choose what kind of devices you want to use the app for. For this tutorial we will allow this app to be used universally.
 
[[Image:iOS_NameProject_Swift.png | 500px]]
 
A .xcodeproj file will be created in the destination folder.
 
4. Download the '''<span style="color:#FF0000">Phidget iOS Library</span>''' and extract it. Inside you will find iphoneos and iphonesimulator folders. Move the two folders as well as the phidget22.h file into the same directory as the newly created .xcodeproj
 
5. In Xcode, open Project Settings → Build Settings and navigate to the Linking section
 
6. In Linking → Other Linker Flags, following the following steps:
 
Select Any iOS Simulator SDK and enter: $(SRCROOT)/iphonesimulator/libPhidget22.a
 
Select Any iOS SDK and enter: $(SRCROOT)/iphoneos/libPhidget22.a
 
[[Image:iOS_LinkerFlags.png]]
 
7. In Search Paths→Header Search Paths enter $(SRCROOT)
 
[[Image:iOS_HeaderSearchPaths.png]]
 
8. In your header file, add a reference to phidget22.h
 
<syntaxhighlight lang="objc">
#import "phidget22.h"
</syntaxhighlight>
 
The project now has access to Phidgets and we are ready to begin coding.
 
== Edit the Examples ==
 
By following the instructions for your operating system and compiler 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 Objective-C code will be the {{Phidget22API}} Manual:
 
=== Code Snippets ===
 
The following code snippets describe how to do various general tasks with Phidgets. You should be able to find places in the examples where these snippets exist, and modify them to suit your requirements.
 
==== Step One: Initialize and Open ====
First, ensure you have given your program access to Phidgets as described in the [[#Write_your_own_code|Write Your Own Code]] section, Then, you will need to declare your Phidget variable in your code. For example, we can declare a Phidget Digital Output like this:
 
<syntaxhighlight lang="swift">
var ch:PhidgetDigitalInput? = nil
</syntaxhighlight>
 
The object name for any Phidget is listed in the {{Phidget22API}} manual. Every type of Phidget also inherits functionality from the Phidget base class.
 
Next, the Phidget object needs to be initialized and opened.
 
<syntaxhighlight lang="swift">
PhidgetDigitalInput_create(&ch)
Phidget_open(ch)
</syntaxhighlight>
 
==== Step Two: Wait for Attachment (plugging in) of the Phidget ====
Simply calling open does not guarantee you can use the Phidget immediately. To use a Phidget, it must be plugged in (attached). We can handle this by using event driven programming and tracking the attach events and detach events. Alternatively, we can call the following function:
 
<syntaxhighlight lang="swift">
Phidget_openWaitForAttachment(ch, 5000) //wait for attach for 5 seconds, if not time out
</syntaxhighlight>
 
Waiting for attachment will block indefinitely until a connection is made, or until the timeout value is exceeded.
 
To use events to handle attachments, we need to first declare the function that will be called when an attach event is fired - in this case we will call the function gotAttach.
 
<syntaxhighlight lang="swift">
let gotAttach: @convention(c)(PhidgetHandle?, UnsafeMutableRawPointer?) -> () = {phid,context in
    DispatchQueue.main.async(execute: {
        let myObject = Unmanaged<YourViewController>.fromOpaque(context!).takeUnretainedValue()
        myObject.onAttachHandler()
    })
}
</syntaxhighlight>
 
Next, we have to modify our create/open code to emulate the following:
 
<syntaxhighlight lang="swift">
PhidgetDigitalInput_create(&ch)
Phidget_setOnAttachHandler(ch,gotAttach,bridge(self))
Phidget_open(ch)
</syntaxhighlight>
 
The bridge function mentioned above is described here:
 
<syntaxhighlight lang="swift">
func bridge<T : AnyObject>(_ obj : T) -> UnsafeMutableRawPointer {
    return Unmanaged.passUnretained(obj).toOpaque()
}
</syntaxhighlight>
 
==== Step Three: Do Things with the Phidget ====
We recommend the use of event driven programming when working with Phidgets. In a similar way to handling an attach event as described above, we can add an event handler with the following code:
 
<syntaxhighlight lang="swift">
PhidgetDigitalInput_setOnStateChangeHandler(ch, gotStateChange, bridge(self))
</syntaxhighlight>
 
This code will connect a function and an event. In this case, the gotStateChange function will be called when there has been a change to the devices input. Next, we need to create the gotStateChange function.
 
<syntaxhighlight lang="swift">
let gotStateChange: @convention(c)(PhidgetDigitalInputHandle?, UnsafeMutableRawPointer?, CInt) -> () = {_,context,cState in
    var state:Int32 = cState
    DispatchQueue.main.async(execute: {
        let myObject = Unmanaged<YourViewController>.fromOpaque(context!).takeUnretainedValue()
        myObject.onStateChangeHandler(state)
    })
}
</syntaxhighlight>
 
Above, the onStateChangeHandler method is invoked on the main thread. Event data is stored as an Int32.
 
The method onStateChangeHandler is defined as follows:
 
<syntaxhighlight lang="swift">
func onStateChangeHandler(_ state:Int32){
    if  state == 0{
        stateLabel.text = "False"
    }
    else{
        stateLabel.text = "True"
    }
}
</syntaxhighlight>
 
The example shown above simply changes the text of a UITextField to display whether the input is true or false.
 
Some events such as the attach or detach events belong to the base Phidget object and are thus common to all Phidgets. Please refer to the {{Phidget22API}} manual and the Swift examples for a list of events and their usage.
 
If events do not suit your needs, you can also poll the device directly for data using code like this:
 
<syntaxhighlight lang="swift">
var state = 0
PhidgetDigitalOutput_getState(ch, &state)
stateLabel.text = state ? "True" : "False"
</syntaxhighlight>
 
Polling code can be used inside a polling loop as an alternative to event driven programming.
 
==== Step Four: Close and Delete ====
At the end of your program, don't forget to close your device.
 
<syntaxhighlight lang="swift">
Phidget_close(ch)
PhidgetDigitalInput_delete(&digin)
</syntaxhighlight>
 
== Further Reading ==
 
[[Phidget Programming Basics]] - Here you can find the basic concepts to help you get started with making your own programs that use Phidgets.
 
[[Data Interval/Change Trigger]] - Learn about these two properties that control how much data comes in from your sensors.
 
[[Using Multiple Phidgets]] - It can be difficult to figure out how to use more than one Phidget in your program. This page will guide you through the steps.
 
[[Polling vs. Events]] - Your program can gather data in either a polling-driven or event-driven manner. Learn the difference to determine which is best for your application.
 
[[Logging, Exceptions, and Errors]] - Learn about all the tools you can use to debug your program.
 
[[Phidget Network Service]] - Phidgets can be controlled and communicated with over your network- either wirelessly or over ethernet.
 
 
== Common Problems and Solutions / Workarounds ==
'''<span style="color:#FF0000">If you know of common problems using this lanaguage (for example, having to create sub-VIs when using multiple phidgets in labview) put them here. </span>'''

Latest revision as of 21:39, 10 August 2023


We provide support for the Swift language on macOS. We also provide instructions on how to get your project started in Xcode for use in macOS and iOS applications. Select your operating system below, and follow the instructions to get your project running with Phidgets.

Once you have set up your development environment to run with Phidgets, we recommend you follow our guide on Phidget Programming Basics. The guide will showcase the fundamentals of programming with Phidgets.

Setup Guide

Swift - Select Development Environment

Select your Development Environment:

macOS

iOS

Language - Swift

Windows with Xcode

Welcome to using Phidgets with Swift! By using Swift, you will have access to the complete Phidget22 API, including events.

Xcode is an integrated development environment for macOS. It is commonly used as a tool for developing software for macOS and iOS applications.

Requirements

First, make sure you have the following installed:

● Phidgets Drivers for MacOS (see Part 1 of this user guide)

Xcode from the Mac App Store


You will also need to install CocoaPods in order to access the Phidget libraries for Swift. You can do this by opening the terminal and entering the following command:

Using Phidgets in Your Programs

There are two ways you can use Phidgets in Xcode. You can either start from a sample project provided by our code sample generator, or you can start a new project from scratch.

Select your preferred method below for instructions:

«
»

Language - Swift

Use Our Examples

Now that you have Xcode and CocoaPods installed, download a Swift example that will work with your Phidget:

Swift Examples

After opening the example, you will notice that there is a file called Podfile

Use Our Examples

If you open the Podfile, you can see that there is a reference to the Phidget22Swift pod. Note that no version number is included, so the newest available version of the Phidget22Swift pod will be installed:

Use Our Examples

To install the Phidget libraries, open a terminal at the example location and enter the following command:

pod install

Use Our Examples

After the libraries are installed, open the generated .xcworkspace file:

Use Our Examples

Next, simply press run:

Use Our Examples

Here is an example output:

You should now have the example up and running for your device. This would be a good time to play around with the device and experiment with some of its functionality.

Write Code

You should now have working examples and a project that is configured. This next teaching section will help you understand how the examples were written so you can start writing your own code.

Remember: your main reference for writing Swift code will be:

● The Phidget22 API Manual

● Swift example code

Write Code

Step One: Create And Address

First, create a Phidget object. For example, we can create a digital input object like this:

let ch = DigitalInput()

Next, we can address which Phidget we want to connect to by setting parameters such as DeviceSerialNumber.

ch.setDeviceSerialNumber(496911);

This guide won't go in-depth on error handling, but here is an example of the previous code with error handling:

do{
  try ch.open
}catch let error as PhidgetError{
  //handle error
}

Write Code

Step Two: Open And Wait For Attachment

After we have specified which Phidget to connect to, we can open the Phidget object like this:

ch.open(timeout: 5000)

To use a Phidget, it must be plugged in (attached). We can handle this by calling open(timeout), which will block until a connection is made, or until the timeout expires. Simply calling open() does not guarantee you can use the Phidget immediately.

Instead, you can verify the device is attached by using an attach handler. To use events to handle attachments, we have to modify our code slightly:

PhidgetDigitalInputHandle ch;
PhidgetDigitalInput_create(&ch);
ch.attach.addHandler(attach_handler)
Phidget_open(ch)

Write Code

Step Two: Open And Wait For Attachment

Next, we have to declare the function that will be called when an attach event is fired - in this case the function onAttachHandler will be called:

func attach_handler(sender: Phidget){
  let attachedDevice = sender as! DigitalInput
  //configure device here
}

We recommend using this attach handler to set any initialization parameters for the channel such as DataInterval and ChangeTrigger from within the AttachHandler, so the parameters are set as soon as the device becomes available.

Write Code

Step Three: Do Things With The Phidget

We recommend the use of event driven programming when working with Phidgets. In a similar way to handling an attach event as described above, we can also add an event handler for a state change event:

ch.attach.addHandler(attach_handler)
ch.stateChange.addhandler(stateChange_handler)
ch.open()

This code will connect a function to an event. In this case, the onStateChangeHandler function will be called when there has been a change to the channel's input.

Write Code

Step Three: Do Things With The Phidget

Next, we need to create the onStateChangeHandler function:

func stateChange_handler(sender: DigitalInput, state: Bool){
  if(state){
    //state is true
  }
  else{
    //State is false
  }
}

If you are using multiple Phidgets in your program, check out our page on Using Multiple Phidgets for information on how to properly address them and use them in events.

Write Code

Step Three: Do Things With The Phidget

If events do not suit your needs, you can also poll the device directly for data using code like this:

var state = ch.getState()
stateLabel.text = state ? "True" : "False"

Important Note: There will be a period of time between the attachment of a Phidget sensor and the availability of the first data from the device. Any attempts to get this data before it is ready will result in an error code, and a specific nonsensical result. See more information on this on our page for Unknown Values.

Write Code

Step Three: Do Things With The Phidget

Some Phidget devices have functions that deal with specific predefined values called enumerations. Enumerations commonly provide readable names to a set of numbered options.

Enumerations with Phidgets in Swift will take the form of Phidget22Swift.EnumerationType.enumerationName.

For example, specifying a SensorType to use the 1142 for a voltage input would look like:

Phidget22Swift.VoltageSensorType.PN_1142

and specifying a K-Type thermocouple for a temperature sensor would be:

Phidget22Swift.ThermocoupleType.K

The Phidget error code for timing out could be specified as:

Phidget22Swift.ErrorCode.timeout

You can find the Enumeration Type under the Enumerations section of the Phidget22 API for your device, and the Enumeration Name in the drop-down list within.

Write Code

Step Four: Close

At the end of your program, be sure to close your device:

ch.close()

What's Next?

Now that you've set up Phidgets in your programming environment, you should read our guide on Phidget Programming Basics to learn the fundamentals of programming with Phidgets.

Continue reading below for advanced information and troubleshooting for your device.

«
»

Language - Swift

Setting up a New Project

Whether you are building a project from scratch, or adding Phidget functionality to an existing project, you will need to configure your development environment to properly link the Phidget libraries. To begin, create a new Xcode project:

Setting up a New Project

Next, select a macOS application:

Setting up a New Project

Name the project, select Swift as the language, and continue:

Setting up a New Project

Now that your project is created, you need to add the Phidget libraries (using CocoaPods). Open a terminal at the example location and enter the following command:

pod init

Setting up a New Project

This will create a new Podfile. Open the Podfile in your favorite text editor and add a reference to the Phidget22Swift pod:

Setting up a New Project

Save your edit to the Podfile, and then enter the following command in the terminal which was opened at the example location:

pod install

Setting up a New Project

After running the command, open the xcworkspace file and access the Phidget libraries by adding the following line to the top of your files:

import Phidget22Swift

Success! The project now has access to Phidgets and we are ready to begin coding.

Write Code

You should now have working examples and a project that is configured. This next teaching section will help you understand how the examples were written so you can start writing your own code.

Remember: your main reference for writing Swift code will be:

● The Phidget22 API Manual

● Swift example code

Write Code

Step One: Create And Address

First, create a Phidget object. For example, we can create a digital input object like this:

let ch = DigitalInput()

Next, we can address which Phidget we want to connect to by setting parameters such as DeviceSerialNumber.

ch.setDeviceSerialNumber(496911);

This guide won't go in-depth on error handling, but here is an example of the previous code with error handling:

do{
  try ch.open
}catch let error as PhidgetError{
  //handle error
}

Write Code

Step Two: Open And Wait For Attachment

After we have specified which Phidget to connect to, we can open the Phidget object like this:

ch.open(timeout: 5000)

To use a Phidget, it must be plugged in (attached). We can handle this by calling open(timeout), which will block until a connection is made, or until the timeout expires. Simply calling open() does not guarantee you can use the Phidget immediately.

Instead, you can verify the device is attached by using an attach handler. To use events to handle attachments, we have to modify our code slightly:

PhidgetDigitalInputHandle ch;
PhidgetDigitalInput_create(&ch);
ch.attach.addHandler(attach_handler)
Phidget_open(ch)

Write Code

Step Two: Open And Wait For Attachment

Next, we have to declare the function that will be called when an attach event is fired - in this case the function onAttachHandler will be called:

func attach_handler(sender: Phidget){
  let attachedDevice = sender as! DigitalInput
  //configure device here
}

We recommend using this attach handler to set any initialization parameters for the channel such as DataInterval and ChangeTrigger from within the AttachHandler, so the parameters are set as soon as the device becomes available.

Write Code

Step Three: Do Things With The Phidget

We recommend the use of event driven programming when working with Phidgets. In a similar way to handling an attach event as described above, we can also add an event handler for a state change event:

ch.attach.addHandler(attach_handler)
ch.stateChange.addhandler(stateChange_handler)
ch.open()

This code will connect a function to an event. In this case, the onStateChangeHandler function will be called when there has been a change to the channel's input.

Write Code

Step Three: Do Things With The Phidget

Next, we need to create the onStateChangeHandler function:

func stateChange_handler(sender: DigitalInput, state: Bool){
  if(state){
    //state is true
  }
  else{
    //State is false
  }
}

If you are using multiple Phidgets in your program, check out our page on Using Multiple Phidgets for information on how to properly address them and use them in events.

Write Code

Step Three: Do Things With The Phidget

If events do not suit your needs, you can also poll the device directly for data using code like this:

var state = ch.getState()
stateLabel.text = state ? "True" : "False"

Important Note: There will be a period of time between the attachment of a Phidget sensor and the availability of the first data from the device. Any attempts to get this data before it is ready will result in an error code, and a specific nonsensical result. See more information on this on our page for Unknown Values.

Write Code

Step Three: Do Things With The Phidget

Some Phidget devices have functions that deal with specific predefined values called enumerations. Enumerations commonly provide readable names to a set of numbered options.

Enumerations with Phidgets in Swift will take the form of Phidget22Swift.EnumerationType.enumerationName.

For example, specifying a SensorType to use the 1142 for a voltage input would look like:

Phidget22Swift.VoltageSensorType.PN_1142

and specifying a K-Type thermocouple for a temperature sensor would be:

Phidget22Swift.ThermocoupleType.K

The Phidget error code for timing out could be specified as:

Phidget22Swift.ErrorCode.timeout

You can find the Enumeration Type under the Enumerations section of the Phidget22 API for your device, and the Enumeration Name in the drop-down list within.

Write Code

Step Four: Close

At the end of your program, be sure to close your device:

ch.close()

What's Next?

Now that you've set up Phidgets in your programming environment, you should read our guide on Phidget Programming Basics to learn the fundamentals of programming with Phidgets.

Continue reading below for advanced information and troubleshooting for your device.

«
»

Language - Swift

iOS with Xcode

Welcome to using Phidgets with Swift! By using Swift, you will have access to the complete Phidget22 API, including events.

Xcode is an integrated development environment for macOS. It is commonly used as a tool for developing software for macOS and iOS applications.

Requirements

First, make sure you have the following installed:

● Phidgets Drivers for MacOS on your development machine (see Part 1 of this user guide)

Xcode from the Mac App Store


You will also need to install CocoaPods in order to access the Phidget libraries for Swift. You can do this by opening the terminal and entering the following command:

Using Phidgets in Your Programs

There are two ways you can use Phidgets in Xcode. You can either start from a sample project provided by our code sample generator, or you can start a new project from scratch.

Select your preferred method below for instructions:

«
»

Language - Swift

Use Our Examples

Now that you have Xcode and CocoaPods installed, download a Swift example that will work with your Phidget:

Swift Examples

After opening the example, you will notice that there is a file called Podfile

Use Our Examples

If you open the Podfile, you can see that there is a reference to the Phidget22Swift pod. Note that no version number is included, so the newest available version of the Phidget22Swift pod will be installed:

Use Our Examples

To install the Phidget libraries, open a terminal at the example location and enter the following command:

pod install

Use Our Examples

After the libraries are installed, open the generated .xcworkspace file:

Use Our Examples

Next, select the type of device you would like the application to run on, and press play:

Use Our Examples

Here is an example output:

You should now have the example up and running for your device. This would be a good time to play around with the device and experiment with some of its functionality.

Write Code

You should now have working examples and a project that is configured. This next teaching section will help you understand how the examples were written so you can start writing your own code.

Remember: your main reference for writing Swift code will be:

● The Phidget22 API Manual

● Swift example code

Write Code

Step One: Create And Address

First, create a Phidget object. For example, we can create a digital input object like this:

let ch = DigitalInput()

Next, we can address which Phidget we want to connect to by setting parameters such as DeviceSerialNumber.

ch.setDeviceSerialNumber(496911);

This guide won't go in-depth on error handling, but here is an example of the previous code with error handling:

do{
  try ch.open
}catch let error as PhidgetError{
  //handle error
}

Write Code

Step Two: Open And Wait For Attachment

After we have specified which Phidget to connect to, we can open the Phidget object like this:

ch.open(timeout: 5000)

To use a Phidget, it must be plugged in (attached). We can handle this by calling open(timeout), which will block until a connection is made, or until the timeout expires. Simply calling open() does not guarantee you can use the Phidget immediately.

Instead, you can verify the device is attached by using an attach handler. To use events to handle attachments, we have to modify our code slightly:

PhidgetDigitalInputHandle ch;
PhidgetDigitalInput_create(&ch);
ch.attach.addHandler(attach_handler)
Phidget_open(ch)

Write Code

Step Two: Open And Wait For Attachment

Next, we have to declare the function that will be called when an attach event is fired - in this case the function onAttachHandler will be called:

func attach_handler(sender: Phidget){
  let attachedDevice = sender as! DigitalInput
  //configure device here
}

We recommend using this attach handler to set any initialization parameters for the channel such as DataInterval and ChangeTrigger from within the AttachHandler, so the parameters are set as soon as the device becomes available.

Write Code

Step Three: Do Things With The Phidget

We recommend the use of event driven programming when working with Phidgets. In a similar way to handling an attach event as described above, we can also add an event handler for a state change event:

ch.attach.addHandler(attach_handler)
ch.stateChange.addhandler(stateChange_handler)
ch.open()

This code will connect a function to an event. In this case, the onStateChangeHandler function will be called when there has been a change to the channel's input.

Write Code

Step Three: Do Things With The Phidget

Next, we need to create the onStateChangeHandler function:

func stateChange_handler(sender: DigitalInput, state: Bool){
  if(state){
    //state is true
  }
  else{
    //State is false
  }
}

If you are using multiple Phidgets in your program, check out our page on Using Multiple Phidgets for information on how to properly address them and use them in events.

Write Code

Step Three: Do Things With The Phidget

If events do not suit your needs, you can also poll the device directly for data using code like this:

var state = ch.getState()
stateLabel.text = state ? "True" : "False"

Important Note: There will be a period of time between the attachment of a Phidget sensor and the availability of the first data from the device. Any attempts to get this data before it is ready will result in an error code, and a specific nonsensical result. See more information on this on our page for Unknown Values.

Write Code

Step Three: Do Things With The Phidget

Some Phidget devices have functions that deal with specific predefined values called enumerations. Enumerations commonly provide readable names to a set of numbered options.

Enumerations with Phidgets in Swift will take the form of Phidget22Swift.EnumerationType.enumerationName.

For example, specifying a SensorType to use the 1142 for a voltage input would look like:

Phidget22Swift.VoltageSensorType.PN_1142

and specifying a K-Type thermocouple for a temperature sensor would be:

Phidget22Swift.ThermocoupleType.K

The Phidget error code for timing out could be specified as:

Phidget22Swift.ErrorCode.timeout

You can find the Enumeration Type under the Enumerations section of the Phidget22 API for your device, and the Enumeration Name in the drop-down list within.

Write Code

Step Four: Close

At the end of your program, be sure to close your device:

ch.close()

What's Next?

Now that you've set up Phidgets in your programming environment, you should read our guide on Phidget Programming Basics to learn the fundamentals of programming with Phidgets.

Continue reading below for advanced information and troubleshooting for your device.

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Language - Swift

Setting up a New Project

Whether you are building a project from scratch, or adding Phidget functionality to an existing project, you will need to configure your development environment to properly link the Phidget libraries. To begin, create a new Xcode project:

Setting up a New Project

Next, select an iOS application. For this tutorial, we will use a Single View Application:

Setting up a New Project

Name the project, select Swift as the language, and choose which devices will be supported:

Setting up a New Project

Now that your project is created, you need to add the Phidget libraries (using CocoaPods). Open a terminal at the example location and enter the following command:

pod init

Setting up a New Project

This will create a new Podfile. Open the Podfile in your favorite text editor and add a reference to the Phidget22Swift pod:

Setting up a New Project

Save your edit to the Podfile, and then enter the following command in the terminal which was opened at the example location:

pod install

Setting up a New Project

After running the command, open the xcworkspace file and access the Phidget libraries by adding the following line to the top of your files:

import Phidget22Swift

Success! The project now has access to Phidgets and we are ready to begin coding.

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You should now have working examples and a project that is configured. This next teaching section will help you understand how the examples were written so you can start writing your own code.

Remember: your main reference for writing Swift code will be:

● The Phidget22 API Manual

● Swift example code

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Step One: Create And Address

First, create a Phidget object. For example, we can create a digital input object like this:

let ch = DigitalInput()

Next, we can address which Phidget we want to connect to by setting parameters such as DeviceSerialNumber.

ch.setDeviceSerialNumber(496911);

This guide won't go in-depth on error handling, but here is an example of the previous code with error handling:

do{
  try ch.open
}catch let error as PhidgetError{
  //handle error
}

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Step Two: Open And Wait For Attachment

After we have specified which Phidget to connect to, we can open the Phidget object like this:

ch.open(timeout: 5000)

To use a Phidget, it must be plugged in (attached). We can handle this by calling open(timeout), which will block until a connection is made, or until the timeout expires. Simply calling open() does not guarantee you can use the Phidget immediately.

Instead, you can verify the device is attached by using an attach handler. To use events to handle attachments, we have to modify our code slightly:

PhidgetDigitalInputHandle ch;
PhidgetDigitalInput_create(&ch);
ch.attach.addHandler(attach_handler)
Phidget_open(ch)

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Step Two: Open And Wait For Attachment

Next, we have to declare the function that will be called when an attach event is fired - in this case the function onAttachHandler will be called:

func attach_handler(sender: Phidget){
  let attachedDevice = sender as! DigitalInput
  //configure device here
}

We recommend using this attach handler to set any initialization parameters for the channel such as DataInterval and ChangeTrigger from within the AttachHandler, so the parameters are set as soon as the device becomes available.

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Step Three: Do Things With The Phidget

We recommend the use of event driven programming when working with Phidgets. In a similar way to handling an attach event as described above, we can also add an event handler for a state change event:

ch.attach.addHandler(attach_handler)
ch.stateChange.addhandler(stateChange_handler)
ch.open()

This code will connect a function to an event. In this case, the onStateChangeHandler function will be called when there has been a change to the channel's input.

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Step Three: Do Things With The Phidget

Next, we need to create the onStateChangeHandler function:

func stateChange_handler(sender: DigitalInput, state: Bool){
  if(state){
    //state is true
  }
  else{
    //State is false
  }
}

If you are using multiple Phidgets in your program, check out our page on Using Multiple Phidgets for information on how to properly address them and use them in events.

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Step Three: Do Things With The Phidget

If events do not suit your needs, you can also poll the device directly for data using code like this:

var state = ch.getState()
stateLabel.text = state ? "True" : "False"

Important Note: There will be a period of time between the attachment of a Phidget sensor and the availability of the first data from the device. Any attempts to get this data before it is ready will result in an error code, and a specific nonsensical result. See more information on this on our page for Unknown Values.

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Step Three: Do Things With The Phidget

Some Phidget devices have functions that deal with specific predefined values called enumerations. Enumerations commonly provide readable names to a set of numbered options.

Enumerations with Phidgets in Swift will take the form of Phidget22Swift.EnumerationType.enumerationName.

For example, specifying a SensorType to use the 1142 for a voltage input would look like:

Phidget22Swift.VoltageSensorType.PN_1142

and specifying a K-Type thermocouple for a temperature sensor would be:

Phidget22Swift.ThermocoupleType.K

The Phidget error code for timing out could be specified as:

Phidget22Swift.ErrorCode.timeout

You can find the Enumeration Type under the Enumerations section of the Phidget22 API for your device, and the Enumeration Name in the drop-down list within.

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Step Four: Close

At the end of your program, be sure to close your device:

ch.close()

What's Next?

Now that you've set up Phidgets in your programming environment, you should read our guide on Phidget Programming Basics to learn the fundamentals of programming with Phidgets.

Continue reading below for advanced information and troubleshooting for your device.

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