Cara Terbaik: Membangun Aplikasi Swift Bluetooth Dengan Perkakasan dalam 20 Minit

Dalam tutorial sebelumnya, anda belajar bagaimana menambahkan Bluetooth ke aplikasi Partikel Xenon. Dengan cara itu anda dapat mengawal LED RGB onboard dari aplikasi ujian seperti nRF Connect atau Light Blue Explorer.

Dalam catatan ini, kita akan mengambilnya selangkah lagi. Kami akan mengembangkan aplikasi Swift untuk mengawal led Particle Mesh RGB. Sekiranya semuanya berjalan lancar, anda mesti mempunyai aplikasi yang berfungsi dalam masa 20 minit!

Mari kita mulakan.

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Muat turun versi PDF di sini.

Bersiap sedia

  • Pasang Xcode. Anda boleh memuat turunnya dari App store di sini.
  • Anda juga memerlukan log masuk Apple. Saya menggunakan e-mel iCloud saya. Anda boleh membuat akaun baru dalam Xcode jika anda belum memilikinya.
  • Pasang kod contoh RGB pada papan Particle Mesh.

Buat projek

Setelah semuanya dipasang, mari masuk ke perkara yang menyeronokkan!

Buka Xcode dan pergi ke Fail → Projek Baru.

Projek Baru Xcode

Pilih Aplikasi Paparan Tunggal.

Maklumat Projek Baru

Kemudian kemas kini Nama Projek sesuai dengan keinginan anda. Saya juga telah menukar pengenalan organisasi saya menjadi com.jaredwolff. Ubah suai mengikut kesesuaian anda!

Pilih lokasi untuk menyimpannya.

Seterusnya cari Info.plist anda .

Info.plist di Xcocde

Kemas kini info.plistdengan menambahkanPrivacy - Bluetooth Peripheral Usage Description

Huraian yang akhirnya saya gunakan adalah App uses Bluetooth to connect to the Particle Xenon RGB Example

Ini membolehkan anda menggunakan Bluetooth dalam aplikasi anda jika anda ingin melepaskannya.

Sekarang, mari buat semuanya berfungsi dengan minimum!

Minimum berfungsi

Gambar bahagian baru

Seterusnya, kami akan mendapat aplikasi yang berfungsi minimum untuk menyambung dan melakukan penemuan perkhidmatan. Sebilangan besar tindakan akan berlaku di ViewController.swift.

Mari import pertama CoreBluetooth

 import CoreBluetooth 

Ini membolehkan kita mengawal fungsi Tenaga Rendah Bluetooth di iOS. Kemudian mari tambah kedua CBPeripheralDelegatedan CBCentralManagerDelegateke ViewControllerkelas.

 class ViewController: UIViewController, CBPeripheralDelegate, CBCentralManagerDelegate { 

Sekarang mari kita buat pemboleh ubah peribadi tempatan untuk menyimpan pengurus pusat dan periferal sebenar. Kami akan menyiapkannya sebentar lagi.

 // Properties private var centralManager: CBCentralManager! private var peripheral: CBPeripheral! 

Dalam viewDidLoadfungsi anda , mari masukcentralManager

 centralManager = CBCentralManager(delegate: self, queue: nil) 

Penetapan delegate: selfitu penting. Jika tidak, negeri pusat tidak pernah berubah semasa permulaan.

Sebelum kita melangkah lebih jauh, mari buat fail yang berasingan dan namakannya ParticlePeripheral.swift. Ia boleh diletakkan di mana sahaja tetapi saya meletakkannya dalam 'kumpulan' berasingan yang disebut Model untuk kemudian.

Di dalamnya kita akan membuat beberapa pemboleh ubah awam yang mengandungi UUID untuk Particle Board kita. Mereka mesti kelihatan biasa!

 import UIKit import CoreBluetooth class ParticlePeripheral: NSObject { /// MARK: - Particle LED services and charcteristics Identifiers public static let particleLEDServiceUUID = CBUUID.init(string: "b4250400-fb4b-4746-b2b0-93f0e61122c6") public static let redLEDCharacteristicUUID = CBUUID.init(string: "b4250401-fb4b-4746-b2b0-93f0e61122c6") public static let greenLEDCharacteristicUUID = CBUUID.init(string: "b4250402-fb4b-4746-b2b0-93f0e61122c6") public static let blueLEDCharacteristicUUID = CBUUID.init(string: "b4250403-fb4b-4746-b2b0-93f0e61122c6") } 

Kembali ViewController.swiftmari kita satukan bit Bluetooth.

Bit Bluetooth

Gambarajah aliran untuk Bluetooth Swift di iOS

Semua kaitan dengan Bluetooth adalah berdasarkan acara. Kami akan menentukan beberapa fungsi yang mengendalikan acara ini. Inilah yang penting:

centralManagerDidUpdateStatekemas kini apabila Periferal Bluetooth dihidupkan atau dimatikan. Ini akan menyala ketika aplikasi pertama kali dimulakan sehingga anda mengetahui keadaan Bluetooth. Kami juga mula mengimbas di sini.

Kejadian centralManagerdidDiscoverberlaku semasa anda menerima hasil imbasan. Kami akan menggunakannya untuk memulakan sambungan.

The centralManagerdidConnectevent kebakaran apabila peranti disambungkan. Kami akan memulakan penemuan peranti di sini. Catatan: Penemuan peranti adalah cara kami menentukan perkhidmatan dan ciri apa yang tersedia. Ini adalah kaedah yang baik untuk mengesahkan jenis peranti yang kita sambungkan.

The peripheraldidDiscoverServicesAcara pertama apabila semua perkhidmatan yang telah ditemui. Notis yang kami telah beralih dari centralManageryang peripheralsekarang kita dihubungkan. Kami akan memulakan penemuan ciri di sini. Kami akan menggunakan UUID perkhidmatan RGB sebagai sasarannya.

The peripheraldidDiscoverCharacteristicsForevent akan menyediakan semua ciri-ciri menggunakan UUID perkhidmatan yang diberikan. Ini adalah langkah terakhir dalam melakukan penemuan peranti sepenuhnya. Berbulu tetapi hanya perlu dilakukan sekali semasa fasa penyambungan!

Defining all the Bluetooth functions.

Now that we know what the functions events that get triggered. We'll define them in the logical order that they happen during a connection cycle.

First, we'll define centralManagerDidUpdateState to start scanning for a device with our Particle RGB LED Service. If Bluetooth is not enabled, it will not do anything.

 // If we're powered on, start scanning func centralManagerDidUpdateState(_ central: CBCentralManager) { print("Central state update") if central.state != .poweredOn { print("Central is not powered on") } else { print("Central scanning for", ParticlePeripheral.particleLEDServiceUUID); centralManager.scanForPeripherals(withServices: [ParticlePeripheral.particleLEDServiceUUID], options: [CBCentralManagerScanOptionAllowDuplicatesKey : true]) } } 

Defining the centralManagerdidDiscover is our next step in the process. We know we've found a device if this event has occurred.

 // Handles the result of the scan func centralManager(_ central: CBCentralManager, didDiscover peripheral: CBPeripheral, advertisementData: [String : Any], rssi RSSI: NSNumber) { // We've found it so stop scan self.centralManager.stopScan() // Copy the peripheral instance self.peripheral = peripheral self.peripheral.delegate = self // Connect! self.centralManager.connect(self.peripheral, options: nil) } 

So, we stop scanning using self.centralManager.stopScan(). We set the peripheral so it persists through the app. Then we connect to that device using self.centralManager.connect

Once connected, we need to double check if we're working with the right device.

 // The handler if we do connect succesfully func centralManager(_ central: CBCentralManager, didConnect peripheral: CBPeripheral) { if peripheral == self.peripheral { print("Connected to your Particle Board") peripheral.discoverServices([ParticlePeripheral.particleLEDServiceUUID]) } } 

By comparing the two peripherals we'll know its the device we found earlier. We'll kick off a services discovery using peripheral.discoverService. We can use ParticlePeripheral.particleLEDServiceUUID as a parameter. That way we don't pick up any services we don't care about.

Once we finish the discovering services, we'll get a didDiscoverServices event. We iterate through all the "available" services. (Though there will only be one!)

 // Handles discovery event func peripheral(_ peripheral: CBPeripheral, didDiscoverServices error: Error?) { if let services = peripheral.services { for service in services { if service.uuid == ParticlePeripheral.particleLEDServiceUUID { print("LED service found") //Now kick off discovery of characteristics peripheral.discoverCharacteristics([ParticlePeripheral.redLEDCharacteristicUUID, ParticlePeripheral.greenLEDCharacteristicUUID, ParticlePeripheral.blueLEDCharacteristicUUID], for: service) return } } } } 

By this point this is the third time we're checking to make sure we have the correct service. This becomes more handy later when there are many characteristics and many services.

We call peripheral.discoverCharacteristics with an array of UUIDs for the characteristics we're looking for. They're all the UUIDs that we defined in ParticlePeripheral.swift.

Finally, we handle the didDiscoverCharacteriscsFor event. We iterate through all the available characteristics. As we iterate we compare with the ones we're looking for.

 // Handling discovery of characteristics func peripheral(_ peripheral: CBPeripheral, didDiscoverCharacteristicsFor service: CBService, error: Error?) { if let characteristics = service.characteristics { for characteristic in characteristics { if characteristic.uuid == ParticlePeripheral.redLEDCharacteristicUUID { print("Red LED characteristic found") } else if characteristic.uuid == ParticlePeripheral.greenLEDCharacteristicUUID { print("Green LED characteristic found") } else if characteristic.uuid == ParticlePeripheral.blueLEDCharacteristicUUID { print("Blue LED characteristic found"); } } } } 

At this point we're ready to do a full device discovery of our Particle Mesh device. In the next section we'll test what we have to make sure things are working ok.

Testing our minimal example

Gambar bahagian mengenai ujian

Before we get started, if you run into trouble I've put some troubleshooting steps in the footnotes.

To test, you'll have to have an iPhone with Bluetooth Low Energy. Most modern iPhones have it. The last iPhone not to have it I believe was either the iPhone 4 or 3Gs. (so you're likely good)

First, plug it into your computer.

Go to the top by the play and stop buttons. Select your target device. In my case I chose my phone (Jared's iPhone). You can also use an iPad.

Pilih jenis peranti

Then you can hit Command + R or hit that Play button to load the app to your phone.

Make sure you have your log tab open. Enable it by clicking the bottom pane button in the top right corner.

Panel bawah dalam Xcode untuk log

Make sure you have a mesh device setup and running the example code. You can go to this post to get it. Remember your Particle Mesh board needs to be running device OS 1.3.0 or greater for Bluetooth to work!

Once both the firmware and app is loaded, let's check the log output.

It should look something like this:

View loaded Central state update Central scanning for B4250400-FB4B-4746-B2B0-93F0E61122C6 Connected to your Particle Board LED service found Red LED characteristic found Green LED characteristic found Blue LED characteristic found 

This means that your Phone has connected, found the LED service! The characteristics also being discovered is important here. Without those we wouldn't be able to send data to the mesh device.

Next step is to create some sliders so we can update the RGB values on the fly.

Slide to the left. Slide to the right.

Next we're going to add some elements to our Main.storyboard. Open Main.storyboard and click on the View underneath View Controller.

Mengemas kini paparan dalam Xcode

Then click on the Library button. (It looks like the old art Apple used for the home button)

Butang perpustakaan dalam Xcode

You'll get a pop-up with all the choices that you can insert into your app.

Panel perpustakaan dalam Xcode

Drag three Labels and copy three Sliders to your view.

Menyeret Label ke Paparan Xcode

You can double click on the labels and rename them as you go.

Seret Penggeser ke Paparan Xcode

If you click and hold, some handy alignment tools will popup. They'll even snap to center!

Alat penjajaran dalam Xcode

You can also select them all and move them together. We'll align them vertically and horizontally.

In order for them to stay in the middle, let's remove the autoresizing property. Click the Ruler icon on the top right. Then click each of the red bars. This will ensure that your labels and sliders stay on the screen!

Panel pembaris dalam Xcode

Next let's click the Show Assistant Editor button. (Looks like a Venn diagram)

Tunjukkan butang Penolong Editor dalam Xcode

Note: make sure that ViewController.swift is open in your Assistant Editor.

Pilihan automatik dalam Penolong Editor

Then underneath the /properties section, Control-click and dragthe Red Slider into your code.

Seret gelangsar ke kod

Repeat with all the other ones. Make sure you name them something different. Your code should look like this when you're done:

 // Properties private var centralManager: CBCentralManager! private var peripheral: CBPeripheral! // Sliders @IBOutlet weak var redSlider: UISlider! @IBOutlet weak var greenSlider: UISlider! @IBOutlet weak var blueSlider: UISlider! 

This allow us to access the value of the sliders.

Next, let's attach the Value Changed event to each of the sliders. Right click on the Red Slider in the folder view.

Nilai seret mengubah acara menjadi kod

It should give you some options for events. Click and drag the Value Changed event to your code. Make sure you name it something that makes sense. I used RedSliderChanged for the Red Slider.

Repeat two more times. Your code should look like this at the end of this step:

 @IBAction func RedSliderChanged(_ sender: Any) { } @IBAction func GreenSliderChanged(_ sender: Any) { } @IBAction func BlueSliderChanged(_ sender: Any) { } 

I've also selected each of the sliders to and un-checked Enabled. That way you can't move them. We'll enable them later on in code.

Lumpuhkan slaid secara lalai

Also, this is a great time to change the maximum value to 255. Also set the default value from 0.5 to 0.

Tetapkan nilai lalai dan nilai maksimum slider

Back at the top of the file. Let's create some local variables for each of the characteristics. We'll use these so we can write the slider variables to the Particle Mesh board.

 // Characteristics private var redChar: CBCharacteristic? private var greenChar: CBCharacteristic? private var blueChar: CBCharacteristic? 

Now, let's tie everything together!

In the didDiscoverCharacteristicsFor callback function. Let's assign those characteristics. For example

 if characteristic.uuid == ParticlePeripheral.redLEDCharacteristicUUID { print("Red LED characteristic found") redChar = characteristic 

As we find each characteristic, we can also enable each of the sliders in the same spot.

 // Unmask red slider redSlider.isEnabled = true 

In the end your didDiscoverCharacteristicsFor should look like:

 // Handling discovery of characteristics func peripheral(_ peripheral: CBPeripheral, didDiscoverCharacteristicsFor service: CBService, error: Error?) { if let characteristics = service.characteristics { for characteristic in characteristics { if characteristic.uuid == ParticlePeripheral.redLEDCharacteristicUUID { print("Red LED characteristic found") redChar = characteristic redSlider.isEnabled = true } else if characteristic.uuid == ParticlePeripheral.greenLEDCharacteristicUUID { print("Green LED characteristic found") greenChar = characteristic greenSlider.isEnabled = true } else if characteristic.uuid == ParticlePeripheral.blueLEDCharacteristicUUID { print("Blue LED characteristic found"); blueChar = characteristic blueSlider.isEnabled = true } } } } 

Now, let's update the RedSliderChangedGreenSliderChanged and BlueSliderChanged functions. What we want to do here is update the characteristic associated with the Changed function. I created a separate function called writeLEDValueToChar. We'll pass in the characteristic and the data.

 private func writeLEDValueToChar( withCharacteristic characteristic: CBCharacteristic, withValue value: Data) { // Check if it has the write property if characteristic.properties.contains(.writeWithoutResponse) && peripheral != nil { peripheral.writeValue(value, for: characteristic, type: .withoutResponse) } } 

Now add a call to writeLEDValueToChar to each of the Changed functions. You will have to cast the value to a Uint8. (The Particle Mesh device expects an unsigned 8-bit number.)

 @IBAction func RedSliderChanged(_ sender: Any) { print("red:",redSlider.value); let slider:UInt8 = UInt8(redSlider.value) writeLEDValueToChar( withCharacteristic: redChar!, withValue: Data([slider])) } 

Repeat this for GreenSliderChanged and BlueSliderChanged. Make sure you changed red to green and blue for each!

Finally, to keep things clean, i've also added a function that handles Bluetooth disconnects.

 func centralManager(_ central: CBCentralManager, didDisconnectPeripheral peripheral: CBPeripheral, error: Error?) { 

Inside, we should reset the state of the sliders to 0 and disable them.

 if peripheral == self.peripheral { print("Disconnected") redSlider.isEnabled = false greenSlider.isEnabled = false blueSlider.isEnabled = false redSlider.value = 0 greenSlider.value = 0 blueSlider.value = 0 

It's a good idea to reset self.peripheral to nil that way we're not ever trying to write to a phantom device.

 self.peripheral = nil 

Finally, because we've disconnected, start scanning again!

 // Start scanning again print("Central scanning for", ParticlePeripheral.particleLEDServiceUUID); centralManager.scanForPeripherals(withServices: [ParticlePeripheral.particleLEDServiceUUID], options: [CBCentralManagerScanOptionAllowDuplicatesKey : true]) } 

Alright! We just about ready to test. Let's move on to the next (and final) step.

Test the sliders.

Ujian bahagian seterusnya!

The hard work is done. Now it's time to play!

The easiest way to test everything is to click the Play button in the top left or the Command + R keyboard shortcut. Xcode will load the app to your phone. You should see a white screen proceeded by a screen with your sliders!

The sliders should stay greyed out until connected to your Particle Mesh board. You can check your log output if the connection has been established.

View loaded Central state update Central scanning for B4250400-FB4B-4746-B2B0-93F0E61122C6 Connected to your Particle Board LED service found Red LED characteristic found Green LED characteristic found Blue LED characteristic found 

(Look familiar? We're connected!)

Sekiranya anda mengikuti semuanya dengan sempurna, anda seharusnya dapat menggerakkan slider. Lebih baik lagi, LED RGB pada papan Particle Mesh harus berubah warna.

Keputusan ujian akhir

Kesimpulannya

Dalam artikel ini, anda telah mempelajari cara menyambungkan papan Particle Mesh dan peranti iOS anda melalui Bluetooth. Kami telah belajar bagaimana menghubungkan ke setiap ciri yang ada. Di samping itu, buat antara muka yang bersih untuk melakukan semuanya.

Seperti yang anda bayangkan, anda boleh pergi ke lubang arnab dengan Bluetooth di iOS. Masih banyak lagi yang akan datang dalam panduan saya yang akan datang: The Ultimate Guide to Particle Mesh. Pelanggan dalam senarai saya mendapat akses ke kandungan pra-pelancaran dan potongan apabila dikeluarkan! Klik di sini untuk mendaftar.

Kod

Kod sumber lengkap terdapat di Github. Sekiranya anda merasa berguna, tekan butang bintang. ⭐️