检索蓝牙状态及进一步处理demo2

针对上一篇demo状态检索及处理的进一步优化和细节处理,重新添加了部分逻辑:

蓝牙状态检索.png

主要是针对设备应用退出再次打开后的自动重连做了处理:
当连接过设备后,除了内存下记录设备对象外,将设备的标识做了偏好设置缓存,当程序退出再次打开,在其他优先条件排除外,从偏好设置下读取设备标识,再尝试自动连接

示例代码:

+ (void)load {
    // 程序一启动就开始获取设备状态 (默认一启动时设备状态为未知,暂时这里手动调用了一下获取设备状态的协议方法)
    [[JSBluetoothManager sharedManager] centralManagerDidUpdateState:[JSBluetoothManager sharedManager].centralManager];
    [JSBluetoothManager sharedManager].timer = [NSTimer scheduledTimerWithTimeInterval:3 target:self selector:@selector(getCentralDeviceState) userInfo:nil repeats:YES];

}

+ (void)getCentralDeviceState
{
    JSBluetoothManager *manager = [JSBluetoothManager sharedManager];
    BOOL isOn = manager.centralManager.state == CBCentralManagerStatePoweredOn;
    manager.deviceBluetoothOn = isOn;
    NSLog(@"设备启用状态:%zd,设备连接状态:%zd",manager.deviceBluetoothIsOn,manager.deviceIsConnecting);
    
    // 蓝牙关闭
    if (!isOn) {
        // 自定义alert提示框已在界面中显示 || 当前应用不再前台 不做任何处理
        UIApplicationState appState = [UIApplication sharedApplication].applicationState;
        if (manager.alertController || appState != UIApplicationStateActive) {
            return;
        }
        // 提示蓝牙关闭
        [manager noticeUserToOpenBluetoothService];
        
    } else {
        // 蓝牙开启
        BOOL isConnected = manager.deviceIsConnecting;
        if (isConnected) {
            // 开启并连接状态
            NSLog(@"--->当前设备处于连接状态");
            
        } else {
            // 开启但断开连接状态
            // 如果有绑定设备,自动搜索并连接
            if (manager.peripheralConnected) {
                [manager.centralManager connectPeripheral:manager.peripheralConnected options:nil];
                NSLog(@"---->重新连接到设备");
                return;
            }
            
            // 如果应用退出重启后,根据偏好设置缓存取出上次连接成功后的外设进行自动重连
            NSString *lastPeripheralIdentifierConnected = [[NSUserDefaults standardUserDefaults] objectForKey:kLastPeriphrealIdentifierConnectedKey];
            
            if (lastPeripheralIdentifierConnected.length <= 0 || lastPeripheralIdentifierConnected == nil) {
                return;
            }
            
            NSUUID *uuid = [[NSUUID alloc] initWithUUIDString:lastPeripheralIdentifierConnected];
            // 返回一个数组,此项目中我们只缓存一个外设
            NSArray <CBPeripheral *>*peripheralConnecteds = [manager.centralManager retrievePeripheralsWithIdentifiers:@[uuid]];
            // 可重连设备的标识符存在,但是获取到的外设记录为空,错误处理
            if (peripheralConnecteds.count == 0 || peripheralConnecteds == nil ) {
                
                if (manager.delegate && [manager.delegate respondsToSelector:@selector(js_centralTool:connectFailure:)]) {
                    NSError *error = JS_ERROR(JSCentralErrorConnectAutoConnectFail);
                    [manager.delegate js_centralTool:manager connectFailure:error];
                }
                return;
            }
            
            CBPeripheral *peripheralConnected = peripheralConnecteds.firstObject;
            [manager.centralManager connectPeripheral:peripheralConnected options:nil];
            // 再次记录 并 写入偏好设置进行缓存
            manager.peripheralConnected = peripheralConnected;
            NSLog(@"---->根据偏好设置缓存identifier重新连接到设备");
            
            // 调试代码(应用退出重启后无法通过控制台打印判断)
            UILabel *label = [[UILabel alloc] init];
            label.text = @"根据偏好设置缓存identifier重新连接到设备";
            label.textColor = [UIColor redColor];
            label.backgroundColor = [UIColor blackColor];
            label.frame = [UIApplication sharedApplication].keyWindow.rootViewController.view.frame;
            [[UIApplication sharedApplication].keyWindow.rootViewController.view addSubview:label];
            dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(2 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
                [[UIApplication sharedApplication].keyWindow.rootViewController.view bringSubviewToFront:label];
                
            });

            
        }
        
    }
    
}