IOS 蓝牙 LE 扫描设备未添加到 uitableview

Posted 2023-03-10

【中文标题】IOS 蓝牙 LE 扫描设备未添加到 uitableview

【英文标题】：IOS Bluetooth LE Scanning Devices not adding to the uitableview

【发布时间】：2014-07-11 08:24:18

【问题描述】：

我想使用uitableview实现ios的蓝牙扫描和连接模块。在执行方面，没有项目被添加到列表中。你能告诉我我还需要做什么来显示带有设备名称、uuid 等的蓝牙设备列表吗？

例如， 1.如何将我的对象数组设置为uitableview的数据源？ 2. 点击时如何处理设备之间的蓝牙连接？

 _currentperipheral = peripheral; <--also fails at Thread 1 EXC_BREAKPOINT

以下是我的控制台消息

  2014-07-11 16:34:18.286 marker[6060:60b] Scanning started
2014-07-11 17:53:14.056 marker[6115:60b] Discovered WiT Power Meter at -67

下面是我的模型类：

@interface BTDevice : NSObject 
    NSString *name;
    NSString *macAddress;



@property(nonatomic, retain) NSString *name;
@property(nonatomic, retain) NSString *macAddress;

- (NSString *)getName;
- (NSString *)getMacAddress;

- (void)setName:(NSString *)valueName;
- (void)setMacAddress:(NSString *)valueMacAddress;

@end

以下是我的工作：

- (void)viewDidLoad

    [super viewDidLoad];

    _pendingInit = YES;

    _centralManager = [[CBCentralManager alloc] initWithDelegate:self queue:dispatch_get_main_queue()];
    _currentperipheral=[[CBPeripheral alloc]init];
    _founddevice=FALSE;
    _foundPeripherals = [[NSMutableArray alloc] init];
    _connectedServices = [[NSMutableArray alloc] init];



- (void)viewWillDisappear:(BOOL)animated 

    [_centralManager stopScan];
    NSLog(@"Scanning stopped");
    [super viewWillDisappear:animated];



#pragma mark - Table view data source

- (void)tableView: (UITableView *)tableView
didSelectRowAtIndexPath: (NSIndexPath *)indexPath

    int idx=indexPath.row;
    BTSentCommandViewController * sliderVC = [self.storyboard instantiateViewControllerWithIdentifier:@"BTSentCommandViewController"];



- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView

#warning Potentially incomplete method implementation.
    // Return the number of sections.
    return  [_foundPeripherals count];


- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section

#warning Incomplete method implementation.
    // Return the number of rows in the section.
    return [_foundPeripherals count];




- (void)centralManagerDidUpdateState:(CBCentralManager *)central 
    // You should test all scenarios
    if (central.state != CBCentralManagerStatePoweredOn) 
        return;
    

    if (central.state == CBCentralManagerStatePoweredOn) 
        // Scan for devices

        [_centralManager scanForPeripheralsWithServices:nil options:nil];
        NSLog(@"Scanning started");
    



- (void)centralManager:(CBCentralManager *)central didDiscoverPeripheral:(CBPeripheral *)peripheral advertisementData:(NSDictionary *)advertisementData RSSI:(NSNumber *)RSSI 

    NSLog(@"Discovered %@ at %@", peripheral.name, RSSI);

    if (_currentperipheral != peripheral) 
        // Save a local copy of the peripheral, so CoreBluetooth doesn't get rid of it
        _currentperipheral = peripheral;

        BTDevice *myDevice=[[BTDevice alloc] init];
        [myDevice setName: peripheral.name];

        NSString * macAddress =   [NSString stringWithFormat:@"%@" , peripheral.RSSI];
        [myDevice setMacAddress: macAddress] ;

        [_foundPeripherals addObject:myDevice ] ;

         [self.tableView reloadData];   
        NSLog(@"Connecting to peripheral %@", peripheral);
        [_centralManager connectPeripheral:peripheral options:nil];
    


- (void)centralManager:(CBCentralManager *)central didFailToConnectPeripheral:(CBPeripheral *)peripheral error:(NSError *)error 
    NSLog(@"Failed to connect");
    [self cleanup];



- (void)centralManager:(CBCentralManager *)central didConnectPeripheral:(CBPeripheral *)peripheral 
    NSLog(@"Connected");

    [_centralManager stopScan];
    NSLog(@"Scanning stopped");

    peripheral.delegate = self;

    [peripheral discoverServices:@[[CBUUID UUIDWithString:TRANSFER_SERVICE_UUID]]];


- (void)peripheral:(CBPeripheral *)peripheral didDiscoverServices:(NSError *)error 
    if (error) 
        [self cleanup];
        return;
    

    for (CBService *service in peripheral.services) 
        [peripheral discoverCharacteristics:@[[CBUUID UUIDWithString:TRANSFER_CHARACTERISTIC_UUID]] forService:service];
    
    // Discover other characteristics


- (void)peripheral:(CBPeripheral *)peripheral didDiscoverCharacteristicsForService:(CBService *)service error:(NSError *)error 
    if (error) 
        [self cleanup];
        return;
    

    for (CBCharacteristic *characteristic in service.characteristics) 
        if ([characteristic.UUID isEqual:[CBUUID UUIDWithString:TRANSFER_CHARACTERISTIC_UUID]]) 
            [peripheral setNotifyValue:YES forCharacteristic:characteristic];
        
    



- (void)peripheral:(CBPeripheral *)peripheral didUpdateValueForCharacteristic:(CBCharacteristic *)characteristic error:(NSError *)error 
    if (error) 
        NSLog(@"Error");
        return;
    

    NSString *stringFromData = [[NSString alloc] initWithData:characteristic.value encoding:NSUTF8StringEncoding];

    if ([stringFromData isEqualToString:@"EOM"]) 


        [peripheral setNotifyValue:NO forCharacteristic:characteristic];

        [_centralManager cancelPeripheralConnection:peripheral];
    

    //[_data appendData:characteristic.value];



- (void)peripheral:(CBPeripheral *)peripheral didUpdateNotificationStateForCharacteristic:(CBCharacteristic *)characteristic error:(NSError *)error 

    if (![characteristic.UUID isEqual:[CBUUID UUIDWithString:TRANSFER_CHARACTERISTIC_UUID]]) 
        return;
    

    if (characteristic.isNotifying) 
        NSLog(@"Notification began on %@", characteristic);
     else 
        // Notification has stopped
        [_centralManager cancelPeripheralConnection:peripheral];
    


- (void)centralManager:(CBCentralManager *)central didDisconnectPeripheral:(CBPeripheral *)peripheral error:(NSError *)error 
    _foundPeripherals = nil;

    [_centralManager scanForPeripheralsWithServices:@[[CBUUID UUIDWithString:TRANSFER_SERVICE_UUID]] options:@ CBCentralManagerScanOptionAllowDuplicatesKey : @YES ];


- (void)cleanup 

    // See if we are subscribed to a characteristic on the peripheral
    if (_currentperipheral.services != nil) 
        for (CBService *service in _currentperipheral.services) 
            if (service.characteristics != nil) 
                for (CBCharacteristic *characteristic in service.characteristics) 
                    if ([characteristic.UUID isEqual:[CBUUID UUIDWithString:TRANSFER_CHARACTERISTIC_UUID]]) 
                        if (characteristic.isNotifying) 
                            [_currentperipheral setNotifyValue:NO forCharacteristic:characteristic];
                            return;
                        
                    
                
            
        
    

    [_centralManager cancelPeripheralConnection:_currentperipheral];


- (void)didReceiveMemoryWarning 
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.





- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath

    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"reuseIdentifier" forIndexPath:indexPath];

    if (cell == nil) 
        cell =  [ [UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:@"reuseIdentifier"] ;

        cell.selectionStyle = UITableViewCellSelectionStyleGray;
    

    cell.textLabel.text = [_foundPeripherals objectAtIndex:indexPath.row];
    // Configure the cell...

    return cell;

【参考方案1】：

这里有很多代码，但总体看起来还可以。然而，有两件事很突出。您的 numberOfSectionsInTableView 返回 0 - 因此您的表格中将没有内容。你应该有 -

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView

    // Return the number of sections.
    return 1;

我建议您将 CBPeripheral 存储在您的数据数组中。

此外，一旦你发现了一个外围设备并将其添加到你的数组中，你应该通知 table view 数据源已经更新（这个代码假设你有属性 tableView 包含对你的 tableview 的引用） -

- (void)centralManager:(CBCentralManager *)central didDiscoverPeripheral:(CBPeripheral *)peripheral advertisementData:(NSDictionary *)advertisementData RSSI:(NSNumber *)RSSI 

    NSLog(@"Discovered %@ at %@", peripheral.name, RSSI);

    if (![_foundPeripherals containsObject:peripheral]) 
        [_foundPeripherals addObject:myDevice ] ;

        [self.tableView reloadData];     // Tell the tableview that the data source has changed
    

那么你的cellForRowAtIndexPath就变成了-

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath

    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"reuseIdentifier" forIndexPath:indexPath];

    if (cell == nil) 
        cell =  [ [UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:@"reuseIdentifier"] ;


        cell.selectionStyle = UITableViewCellSelectionStyleGray;
    


    CBPeripheral *peripheral=[_foundPeripherals objectAtIndex:indexPath.row];

    cell.textLabel.text = peripheral.name; 
    // Configure the cell...

    return cell;

选择表格行时连接外围设备 -

- (void)tableView: (UITableView *)tableView
didSelectRowAtIndexPath: (NSIndexPath *)indexPath


    [self performSegueWithIdentifier:@"connectSegue" sender:[_foundPeripherals objectAtIndex:indexPath.row]];  //  This is a segue to your BTSentCommandViewController


-(void) prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender 

     BTSentCommandViewController* sliderVC=( BTSentCommandViewController *)segue.destinationViewController;
     sliderVC.centralManager=_centralManager;
     sliderVC.periperhal=_sender;

在您的BTSentCommandViewController 中，您可以连接到外围设备。您还应该将BTSentCommandViewController 实例设置为外围设备委托并在那里实现所有CBPeripheralDelegate 方法

【讨论】：

我使用了 LightBlue，因此检查了几个设备。至于我的应用程序，他们甚至都没有遵循你的工作。

我必须通过prepareForSegue调用方法连接蓝牙的哪一部分？

我会在 prepareForSegue 中将 CBPeripheral 传递给您的目标视图控制器，然后在 viewWillAppear 中连接它 - 但您可能应该从视图控制器中删除所有 CoreBluetooth 内容并将其放在单独的类 - 它会让你的视图控制器实现更干净