iOS蓝牙LE kCBAdvDataServiceUUID的格式是什么？

Question

在centralManager中:didDiscoverPeripheral:advertisementData:RSSI(下面的完整代码),我在NSDictionary中找到一个名为kCBAdvDataServiceUUIDs的密钥.我正在尝试读取此数据以确定设备上可用的服务.这些数据的格式是什么？课程描述很简单

Unknown (<fff0>)

这是来源:

- (void) centralManager: (CBCentralManager *) central
  didDiscoverPeripheral: (CBPeripheral *) aPeripheral
      advertisementData: (NSDictionary *) advertisementData
                   RSSI: (NSNumber *) RSSI
{
printf("Discovered %s\n", [[aPeripheral name] cStringUsingEncoding: NSUTF8StringEncoding]); // TODO: Remove printfs
    printf("  RSSI: %s\n", [[RSSI stringValue] cStringUsingEncoding: NSUTF8StringEncoding]);
    NSArray *keys = [advertisementData allKeys];
    for (int i = 0; i < [keys count]; ++i) {
        id key = [keys objectAtIndex: i];
        NSString *keyName = (NSString *) key;
        NSObject *value = [advertisementData objectForKey: key];
        if ([value isKindOfClass: [NSArray class]]) {
            printf("   key: %s\n", [keyName cStringUsingEncoding: NSUTF8StringEncoding]);
            NSArray *values = (NSArray *) value;
            for (int j = 0; j < [values count]; ++j) {
                NSObject *aValue = [values objectAtIndex: j];
                printf("       %s\n", [[aValue description] cStringUsingEncoding: NSUTF8StringEncoding]);
                printf("       is NSData: %d\n", [aValue isKindOfClass: [NSData class]]);
            }
        } else {
            const char *valueString = [[value description] cStringUsingEncoding: NSUTF8StringEncoding];
            printf("   key: %s, value: %s\n", [keyName cStringUsingEncoding: NSUTF8StringEncoding], valueString);
        }
    }
}

以下是TI CC2250迷你开发套件中密钥卡的输出:

Discovered (null)
  RSSI: -36
   key: kCBAdvDataServiceUUIDs
       Unknown (<fff0>)
       is NSData: 0
Discovered SimpleBLEPeripheral
  RSSI: -37
   key: kCBAdvDataServiceUUIDs
       Unknown (<fff0>)
       is NSData: 0
   key: kCBAdvDataLocalName, value: SimpleBLEPeripheral
   key: kCBAdvDataTxPowerLevel, value: 0

Answer 1

经过一番挖掘,这是我发现的:

广告数据作为参数传递给centralManager:didDiscoverPeripheral:advertisementData:RSSI是一个NSDictionary,似乎总是包含至少一个名为kCBAdvDataServiceUUIDs的密钥.与此键关联的值是CBUUID类型的对象的NSArray.

尽管在许多地方都使用过CBUUID,但是在iOS 5文档中没有记录CBUUID,包括我见过的每个Apple LE蓝牙LE样本.其中的一个方法是调用data一个返回NSData对象的方法.此NSData对象将UUID编码为一系列字节.

因此,要获得并且在这种情况下,查看BLE广告的UUID中的字节,您可以使用如下代码:

- (void) centralManager: (CBCentralManager *) central
  didDiscoverPeripheral: (CBPeripheral *) aPeripheral
      advertisementData: (NSDictionary *) advertisementData
                   RSSI: (NSNumber *) RSSI
{
    printf("Discovered %s\n", [[aPeripheral name] cStringUsingEncoding: NSUTF8StringEncoding]); // TODO: Remove printfs
    printf("  RSSI: %s\n", [[RSSI stringValue] cStringUsingEncoding: NSUTF8StringEncoding]);
    NSArray *keys = [advertisementData allKeys];
    for (int i = 0; i < [keys count]; ++i) {
        id key = [keys objectAtIndex: i];
        NSString *keyName = (NSString *) key;
        NSObject *value = [advertisementData objectForKey: key];
        if ([value isKindOfClass: [NSArray class]]) {
            printf("   key: %s\n", [keyName cStringUsingEncoding: NSUTF8StringEncoding]);
            NSArray *values = (NSArray *) value;
            for (int j = 0; j < [values count]; ++j) {
                if ([[values objectAtIndex: j] isKindOfClass: [CBUUID class]]) {
                    CBUUID *uuid = [values objectAtIndex: j];
                    NSData *data = uuid.data;
                    printf("      uuid(%d):", j);
                    for (int j = 0; j < data.length; ++j)
                        printf(" %2X", ((UInt8 *) data.bytes)[j]);
                    printf("\n");
                } else {
                    const char *valueString = [[value description] cStringUsingEncoding: NSUTF8StringEncoding];
                    printf("      value(%d): %s\n", j, valueString);
                }
            }
        } else {
            const char *valueString = [[value description] cStringUsingEncoding: NSUTF8StringEncoding];
            printf("   key: %s, value: %s\n", [keyName cStringUsingEncoding: NSUTF8StringEncoding], valueString);
        }
    }
}