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<metadesc>Communicate over USB with sensors, controllers and relays with Phidgets! Our Swift library supports iOS using Xcode.</metadesc>
[[Category:Language]]
== Quick Downloads ==
__NOTOC__


Already know what you're doing? Here you go:
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.


=== Documentation ===
General information of how to use Phidgets with Swift can be found in the '''Write Code''' section of each development environment page. This information is consistent across all pages.


*{{Phidget22API}} (select Swift from the drop-down menu)
==Choose Your Development Environment:==


=== Example Code ===
{{Language_-_Swift_Dev_Environment_Table}}


*{{SampleCode|Swift|Swift Examples}}
== Quick Downloads ==


=== Libraries ===
If you already know what you're doing and just need the files, you can find them all below.


{{MacQuickDownloads}}
=== Documentation ===
{{iOSQuickDownloads}}


== Getting Started with Swift ==
*{{Phidget22API}} (select Swift from the drop-down menu)
Welcome to using Phidgets with Swift! By using Swift, you will have access to the complete {{Phidget22API}}, including events. We also provide example code in Swift for multiple Phidget classes.


== iOS ==
=== Example Code ===
{{IOS_Languages}}
===Xcode===
====Use Our Examples====
One of the best ways to start programming with Phidgets is to use our example code as a guide. In order to run the examples for iOS you will need to download [https://developer.apple.com/xcode/ Xcode] from the Mac App Store.
 
 
You will also need to install [https://cocoapods.org/ CocoaPods] in order to access the Phidget libraries for Swift. You can do this by opening the terminal and entering the following command:
<syntaxhighlight lang='bash'>
sudo gem install cocoapods
</syntaxhighlight>
[[Image:Swift_cocoapods_install.png ‎|link=|center]]


Now that you have Xcode and CocoaPods installed, download a Swift example that will work with your Phidget:
*{{SampleCode|Swift|Swift Examples}}
*{{SampleCode|Swift|Swift Examples}}


===Libraries===


After opening the example, you will notice that there is a file called ''Podfile''
{{AllQuickDownloads}}
[[Image:Swift_example_folder.png|link=|center]]
 
 
If you open this file, 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:
[[Image:Swift_podfile.png|link=|center]]
 
 
To install the Phidget libraries, open a terminal at the example location and enter the following command:
<syntaxhighlight lang='bash'>
pod install
</syntaxhighlight>
[[Image:Swift_pod_install.png|link=|center]]
 
 
After the libraries are installed, open the generated ''.xcworkspace'' file:
[[Image:Swift_open_workspace.png|link=|center]]
 
 
Next simply select the type of device you would like the application to run on and press play:
[[Image:Swift_select_target.png|link=|center]]
 
 
Here is an example output:
[[Image:Swift_phone_example.png|link=|center]]
 
====Configure Your 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:
[[Image:Cocoa_CreateProject.png |link=|center]]
 
 
Next, select an iOS application. For this tutorial's purposes, we will use a Single View Application:
[[Image:iOS_SingleView.png |link=|center]]
 
 
Name the project, select Swift as the language, and choose which devices will be supported:
[[Image:iOS_NameProject_Swift.png|link=|center]]
 
 
Now that your project is created, you need to add the Phidget libraries. In order to do this, you must have CocoaPods installed on your computer (this is covered in detail above in the [[#Use our examples |use our examples]] section). Open a terminal at the example location and enter the following command:
<syntaxhighlight lang='bash'>
pod init
</syntaxhighlight>
[[Image:Swift_pod_init.png|link=|center]]
 
 
This will create a new Podfile. Open the Podfile in your favorite text editor and add a reference to the ''Phidget22Swift'' pod:
[[Image:Swift_folder_podfile.png|link=|center]]
 
 
[[Image:Swift_podfile_edit.png|link=|center]]
 
 
Save your edit to the Podfile, and then enter the following command in the terminal which was opened at the example location:
<syntaxhighlight lang='bash'>
pod install
</syntaxhighlight>
[[Image:Swift_pod_install_example.png|link=|center]]
 
 
After running the command, open the ''xcworkspace'' file and access the Phidget libraries by adding the following line to the top of your files:
<syntaxhighlight lang="swift">
import Phidget22Swift
</syntaxhighlight>
 
 
Success! The project now has access to Phidgets and we are ready to begin coding.
 
==Write Code==
{{WriteCode_Intro|Swift}}
 
=== Step One: Initialize and Open ===
You will need to declare your Phidget object in your code. For example, we can declare a digital input object like this:
<syntaxhighlight lang="swift">
let ch = DigitalInput()
</syntaxhighlight>
 
 
Next, the Phidget object needs to be opened:
<syntaxhighlight lang="swift">
ch.open()
</syntaxhighlight>
 
 
Although we are not including it on this page, you need to include error handling for all Phidget functions. Here is an example of the previous code with error handling:
<syntaxhighlight lang="swift">
do{
  try ch.open
}catch let error as PhidgetError{
  //handle error
}
</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. Alternatively, we can modify our code so we wait for an attachment:
<syntaxhighlight lang="swift">
ch.open(timeout: 5000)
</syntaxhighlight>
Waiting for attachment will block indefinitely until a connection is made, or until the timeout value is exceeded.
 
 
To use events, we have to modify our code slightly:
<syntaxhighlight lang="swift">
ch.attach.addHandler(attach_handler)
Phidget_open(ch)
</syntaxhighlight>
 
Next, we have to declare the function that will be called when an attach event is fired - in this case the function ''attach_handler'' will be called.
 
<syntaxhighlight lang="swift">
func attach_handler(sender: Phidget){
  let attachedDevice = sender as! DigitalInput
  //configure device here
}
</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 also add an event handler for a state change event:
 
<syntaxhighlight lang="swift">
ch.attach.addHandler(attach_handler)
ch.stateChange.addhandler(stateChange_handler)
ch.open()
</syntaxhighlight>
 
This code will connect a function and an event. In this case, the ''stateChange_handler'' function will be called when there has been a change to the devices input. Next, we need to create the ''stateChange_handler'' function:
<syntaxhighlight lang="swift">
func stateChange_handler(sender: DigitalInput, state: Bool){
  if(state){
    //state is true
  }
  else{
    //State is false
  }
}
</syntaxhighlight>
 
 
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 = ch.getState()
stateLabel.text = state ? "True" : "False"
</syntaxhighlight>
 
=== Step Four: Close ===
At the end of your program, be sure to close your device.
<syntaxhighlight lang="swift">
ch.close()
</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 Server]] - Phidgets can be controlled and communicated with over your network- either wirelessly or over ethernet.

Revision as of 19:21, 13 December 2018


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.

General information of how to use Phidgets with Swift can be found in the Write Code section of each development environment page. This information is consistent across all pages.

Choose Your Development Environment:

Swift Development Environments
OS - macOS macOS

SW XCODE MAC.png SW XCODE MAC on.png

OS - iOS iOS

SW XCODE IOS.png SW XCODE IOS on.png

Quick Downloads

If you already know what you're doing and just need the files, you can find them all below.

Documentation

Example Code

Libraries