如何用Wowza Gocoder SDK iOS版开发一个基本功能的直播APP?

这篇文章介绍了如何用Wowza Gocoder SDK iOS版开发一个基本功能的直播APP。 

一、创建一个新的开发项目

首先你需要在Xcode中创建一个APP开发项目 

• 在Xcode中，点击 File ，再点击 New ， 然后选择 Project 创建一个新的项目

• 选择 Single     View Application ，然后点击 Next

• 在     project options的对话框中，输入 Product Name 和 Organization     Name 。 注意， Bundle     Identifier 必须与申请 license key时提交的一样。

• 点击 Next ，设置源代码要保存的路径，然后点击 Create

• 确认Gocoder     SDK 的类库被安装在了项目文件夹中，这一点在Wowza     Gocoder SDK iOS版本的安装中有说明

 

二、添加一个直播按钮

在这一步，你需要在APP的界面上添加一个直播按钮. 

• 在Project     navigator上，选择 Main.storyboard ，然后进入View     Controller

• 从Object     library上拖拽一个按钮，放到到界面生成画布上

• 将这个按钮的text文本设置为"直播"

• 为 ViewController 添加一个叫做 broadcastButton 的referencing     outlet

• @interface ViewController ()

• // Referencing outlet for the broadcast button

• @property (weak, nonatomic) IBOutlet UIButton *broadcastButton;

• @end

 

三、定义APP的参数

添加一个 #import 申明，指向GoCoder SDK的API header，然后在 ViewController.m 定义的 ViewController 类中添加goCoder参数。

#import

 

@interface ViewController ()

 

// The top level GoCoder API interface

@property (nonatomic, strong) WowzaGoCoder*goCoder;

 

// Referencing outlet for the broadcastbutton

@property (weak, nonatomic) IBOutletUIButton *broadcastButton;

 

@end

  

四、注册和初始化SDK

在这一步，你需要在 ViewController.m 的 ViewController Class的 viewDidLoad 方法中添加下面注册和初始化GoCoder SDK的代码。 
注意，请用你的License Key替换 GOSK-XXXX-XXXX-XXXX-XXXX-XXXX

// Register the GoCoder SDK license key

NSError *goCoderLicensingError =[WowzaGoCoder registerLicenseKey:@"GOSK-XXXX-XXXX-XXXX-XXXX-XXXX"];

if (goCoderLicensingError != nil) {

   // Log license key registration failure

   NSLog(@"%@", [goCoderLicensingError localizedDescription]);

} else {

   // Initialize the GoCoder SDK

   self.goCoder = [WowzaGoCoder sharedInstance];

}

  

五、检查APP的权限

对于iOS 10及以上版本，你必须定义APP访问摄像头和麦克风时给用户的授权提示信息。

• 在Project     Inspector选择你的项目目标(build target)，然后点击 Info

• 添加以下 Custom     iOS Target Properties 

    字符串名字:Privacy - Camera Usage Description，对应的值 捕捉摄像头视频用于直播 
    字符串名字:Privacy - Microphone Usage Description，对应的值 捕捉麦克风音频用于直播 

 

六、开启摄像头预览

在 ViewController.m 文件定义的 ViewController Class的 viewDidLoad 方法中加入下面的代码在界面中开启摄像头预览。 

if (self.goCoder != nil) {

  // Associate the U/I view with the SDK camera preview

  self.goCoder.cameraView = self.view;

 

  // Start the camera preview

  [self.goCoder.cameraPreview startPreview];

}

  

七、配置直播相关参数

在 ViewController.m 文件定义的 ViewController Class的 viewDidLoad 方法中加入对直播的相关参数，包括服务器地址(hostAddress)、端口(portNumber)、 应用名(applicationName)和流名(streamName)。这个服务器不限于Wowza Streaming Engine或Wowza Streaming Cloud。 
如果你要往Wowza Streaming Cloud 云平台推流，那么你可以在Wowza Streaming Cloud的Web界面的live streaming详情的 Overview Tab页上找到 Connection Code 

// Get a copy of the active config

WowzaConfig *goCoderBroadcastConfig =self.goCoder.config;

 

// Set the defaults for 720p video

[goCoderBroadcastConfigloadPreset:WZFrameSizePreset1280x720];

 

// Set the connection properties for thetarget Wowza Streaming Engine server or Wowza Cloud account

goCoderBroadcastConfig.hostAddress =@"live.someserver.net";

goCoderBroadcastConfig.portNumber =1935;

goCoderBroadcastConfig.applicationName =@"live";

goCoderBroadcastConfig.streamName =@"myStream";

 

// Update the active config

self.goCoder.config =goCoderBroadcastConfig;

  

八、添加流传输的状态回调

在这一步，我们添加对流传输状态监控的回调。 
1、我们首先要在 ViewController Class的中包含WZStatusCallback协议， 用来对直播流的传输做状态监控：

// Implements the WZStatusCallbackprotocol

@interface ViewController ()

   

2、在 ViewController Class中添加WZStatusCallback协议中定义的方法：

- (void) onWZStatus:(WZStatus *)goCoderStatus {

   // A successful status transition has been reported by the GoCoder SDK

   NSString *statusMessage = nil;

 

   switch (goCoderStatus.state) {

       case WZStateIdle:

            statusMessage = @"Thebroadcast is stopped";

            break;

 

       case WZStateStarting:

            statusMessage = @"Broadcastinitialization";

            break;

 

       case WZStateRunning:

            statusMessage = @"Streaming isactive";

            break;

 

       case WZStateStopping:

            statusMessage = @"Broadcastshutting down";

            break;

   }

 

   if (statusMessage != nil)

       NSLog(@"Broadcast status: %@", statusMessage);

}

 

- (void) onWZError:(WZStatus *)goCoderStatus {

   // If an error is reported by the GoCoder SDK, display an alert dialog

   // containing the error details using the U/I thread

   dispatch_async(dispatch_get_main_queue(), ^{

       UIAlertView *alertDialog =

            [[UIAlertView alloc]initWithTitle:@"Streaming Error"

                                  message:goCoderStatus.description

                                 delegate:nil

                       cancelButtonTitle:@"OK"

                        otherButtonTitles:nil];

       [alertDialog show];

   });

}

 

九、开始直播

在开始直播之前，您还需要为直播按钮加上启动和停止直播的代码： 
在 ViewController Class中添加一个开启和停止直播的代码，当直播按钮被按下时需要调用这个方法。

   - (IBAction)broadcastButtonTapped:(UIButton *)button

{

   // Ensure the minimum set of configuration settings have been specifiednecessary to

   // initiate a broadcast streaming session

   NSError *configValidationError = [self.goCoder.configvalidateForBroadcast];

 

   if (configValidationError != nil) {

       UIAlertView *alertDialog =

            [[UIAlertView alloc]initWithTitle:@"Incomplete Streaming Settings"

                        message:self.goCoder.status.description

                        delegate:nil

                       cancelButtonTitle:@"OK"

                        otherButtonTitles:nil];

       [alertDialog show];

   } else if (self.goCoder.status.state != WZStateRunning) {

       // Start streaming

       [self.goCoder startStreaming:self];

   }

   else {

       // Stop the broadcast that is currently running

       [self.goCoder endStreaming:self];

   }   

}

 

接下来，我们需要添加下面的代码，将上述处理代码与直播按钮的按下动作关联起来:

[self.broadcastButton addTarget:selfaction:@selector(broadcastButtonTapped:)

   forControlEvents:UIControlEventTouchUpInside];

 

十、构建和运行你的APP

点击 Product 按钮，选择 Run 。 

十一、ViewController的例子程序

下面是一个完整的 ViewController Class的例子，代码包括上面讲到的所有内容：

#import "ViewController.h"

#import

 

@interface ViewController ()

 

// The top level GoCoder API interface

@property (nonatomic, strong)WowzaGoCoder *goCoder;

 

// Referencing outlet for the broadcastbutton

@property (weak, nonatomic) IBOutletUIButton *broadcastButton;

 

@end

 

@implementation ViewController

 

- (void)viewDidLoad {

 [super viewDidLoad];

 // Do any additional setup after loading the view, typically from a nib.

 

 // Register the GoCoder SDK license key

 NSError *goCoderLicensingError = [WowzaGoCoderregisterLicenseKey:@"GOSK-XXXX-XXXX-XXXX-XXXX-XXXX"];

 if (goCoderLicensingError != nil) {

   // Log license key registration failure

   NSLog(@"%@", [goCoderLicensingError localizedDescription]);

 } else {

   // Initialize the GoCoder SDK

   self.goCoder = [WowzaGoCoder sharedInstance];

 }

 

 if (self.goCoder != nil) {

   // Associate the U/I view with the SDK camera preview

   self.goCoder.cameraView = self.view;

 

   // Start the camera preview

    [self.goCoder.cameraPreview startPreview];

 }

 

 // Get a copy of the active config

 WowzaConfig *goCoderBroadcastConfig = self.goCoder.config;

 

 // Set the defaults for 720p video

 [goCoderBroadcastConfig loadPreset:WZFrameSizePreset1280x720];

 

 // Set the connection properties for the target Wowza Streaming Engineserver or Wowza Cloud account

 goCoderBroadcastConfig.hostAddress = @"live.someserver.net";

 goCoderBroadcastConfig.portNumber = 1935;

 goCoderBroadcastConfig.applicationName = @"live";

 goCoderBroadcastConfig.streamName = @"myStream";

 

 // Update the active config

 self.goCoder.config = goCoderBroadcastConfig;

 

 [self.broadcastButton addTarget:selfaction:@selector(broadcastButtonTapped:)

          forControlEvents:UIControlEventTouchUpInside];

}

 

- (void)didReceiveMemoryWarning {

 [super didReceiveMemoryWarning];

 // Dispose of any resources that can be recreated.

}

 

- (void) onWZStatus:(WZStatus *)goCoderStatus {

 // A successful status transition has been reported by the GoCoder SDK

 NSString *statusMessage = nil;

 

 switch (goCoderStatus.state) {

   case WZStateIdle:

     statusMessage = @"The broadcast is stopped";

     break;

 

   case WZStateStarting:

     statusMessage = @"Broadcast initialization";

     break;

 

   case WZStateRunning:

     statusMessage = @"Streaming is active";

     break;

 

   case WZStateStopping:

     statusMessage = @"Broadcast shutting down";

     break;

 }

 

 if (statusMessage != nil)

   NSLog(@"Broadcast status: %@", statusMessage);

}

 

- (void) onWZError:(WZStatus *)goCoderStatus {

 // If an error is reported by the GoCoder SDK, display an alert dialog

 // containing the error details using the U/I thread

 dispatch_async(dispatch_get_main_queue(), ^{

   UIAlertView *alertDialog =

   [[UIAlertView alloc] initWithTitle:@"Streaming Error"

                   message:goCoderStatus.description

                  delegate:nil

             cancelButtonTitle:@"OK"

             otherButtonTitles:nil];

   [alertDialog show];

 });

}

 

-(IBAction)broadcastButtonTapped:(UIButton *)button

{

 // Ensure the minimum set of configuration settings have been specifiednecessary to

 // initiate a broadcast streaming session

 NSError *configValidationError = [self.goCoder.configvalidateForBroadcast];

 

 if (configValidationError != nil) {

   UIAlertView *alertDialog =

   [[UIAlertView alloc] initWithTitle:@"Incomplete StreamingSettings"

                   message:self.goCoder.status.description

                  delegate:nil

             cancelButtonTitle:@"OK"

             otherButtonTitles:nil];

   [alertDialog show];

 } else if (self.goCoder.status.state != WZStateRunning) {

   // Start streaming

   [self.goCoder startStreaming:self];

 }

 else {

   // Stop the broadcast that is currently running

   [self.goCoder endStreaming:self];

 }   

}

 

@end

        

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