苹果官方提供Demo
Demo地址下载

IMG_1072.PNG

工具类

.h文件

#import <Foundation/Foundation.h>

@interface ZLUSBPlugInTool : NSObject

/**
 *  判断是否连接成功(插上配件则为服务端)
 *
 *  @return 返回连接状态
 */
+ (BOOL)isConnectSuccess;

@end

.m文件

#import "ZLUSBPlugInTool.h"

#import <ExternalAccessory/ExternalAccessory.h>

static NSMutableArray *_accessoryList; // 连接配件数组
static BOOL _isConnectSuccess;
@implementation ZLUSBPlugInTool

+ (void)load {
    
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(_accessoryDidConnect:) name:EAAccessoryDidConnectNotification object:nil];
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(_accessoryDidDisconnect:) name:EAAccessoryDidDisconnectNotification object:nil];
    [[EAAccessoryManager sharedAccessoryManager] registerForLocalNotifications];
    _accessoryList = [[NSMutableArray alloc] initWithArray:[[EAAccessoryManager sharedAccessoryManager] connectedAccessories]];
    
    // 已连接上配件 - 已经插上硬件,才打开app(通知是无效的,因为还未进入界面)
    if (_accessoryList.count) {
        _isConnectSuccess = YES;
        [[NSUserDefaults standardUserDefaults] setInteger:1 forKey:kProbeKey];
    } else {
        [[NSUserDefaults standardUserDefaults] setInteger:0 forKey:kProbeKey];
    }
}

- (void)dealloc {
    
    [[NSNotificationCenter defaultCenter] removeObserver:self name:EAAccessoryDidConnectNotification object:nil];
    [[NSNotificationCenter defaultCenter] removeObserver:self name:EAAccessoryDidDisconnectNotification object:nil];
    _accessoryList = nil;

}

#pragma mark - 通知配件连接成功(突然插上)
+ (void)_accessoryDidConnect:(NSNotification *)notification {
    _isConnectSuccess = YES;
    
    [[NSUserDefaults standardUserDefaults] setInteger:1 forKey:kProbeKey];
    
    // 连接成功通知
    [[NSNotificationCenter defaultCenter] postNotificationName:kIsConnectSuccessNotificationAndKey object:nil userInfo:@{kIsConnectSuccessKey:@(YES)}];
    
}

#pragma mark - 通知配件断开连接(突然拔掉的情况)
+ (void)_accessoryDidDisconnect:(NSNotification *)notification {
    _isConnectSuccess = NO;
    
     // 断开通知
    [[NSNotificationCenter defaultCenter] postNotificationName:kIsConnectSuccessNotificationAndKey object:nil userInfo:@{kIsConnectSuccessKey:@(NO)}];
    
    [[NSUserDefaults standardUserDefaults] setInteger:0 forKey:kProbeKey];
}

+ (BOOL)isConnectSuccess {
    return _isConnectSuccess;
}