检测蓝牙是否开启

 

检测蓝牙是否开启

这个是比较经典的方法

#include <centralrepository.h> // for CRepository
#include <BTServerSDKCRKeys.h> // for KCRUidBluetoothPowerState, KBTPowerState
#include <BtnotifierAPI.h> // for KPowerModeSettingNotifierUid

Library Required: (所需要的链接)

LIBRARY        centralrepository.lib  //CRepository

Source File:

//-----------------------------------------------------------------------------------
//CBTEngine::CheckBluetoothPowerStateL()
//This will check the Bluetooth power state and if switched off 
//then ask to switch it on.
//------------------------------------------------------------------------------------
 
TBool CBTEngine::CheckBluetoothPowerStateL()
    {
    if(BluetoothPowerStateL())
        {
        return ETrue;
        }
    else
        {
        return TurnBluetoothOnL();
        }
    }
 
// ----------------------------------------------------------------------------
// CBTEngine::BluetoothPowerStateL()
// Get the Bluetooth power state of the device.
// ----------------------------------------------------------------------------
//
TBool CBTEngine::BluetoothPowerStateL()
    {
    CRepository* crep = CRepository::NewLC(KCRUidBluetoothPowerState);
    TInt value = 0;
    User::LeaveIfError(crep->Get(KBTPowerState, value));
    CleanupStack::PopAndDestroy(crep);
 
    return !(value == 0);
    }
 
// ----------------------------------------------------------------------------
// CBTEngine::TurnBluetoothOnL()
// Uses the Notifier API to ask the user to turn on Bluetooth
// if it's not on already.
// ----------------------------------------------------------------------------
//
TBool CBTEngine::TurnBluetoothOnL()
    {  
    RNotifier notifier;
    User::LeaveIfError( notifier.Connect() );
    TPckgBuf<TBool> dummy(ETrue);
    TPckgBuf<TBool> reply(EFalse);
    TRequestStatus status;
    notifier.StartNotifierAndGetResponse(status, 
        KPowerModeSettingNotifierUid, dummy, reply);
    User::WaitForRequest(status);
    notifier.CancelNotifier(KPowerModeSettingNotifierUid);
    notifier.Close();
 
    return reply();
    }

下面的是另外的方法：：

在3rd之前的版本：

TBool GetBluetoothOn()  // BTONOFF
{
 // Create and initialise an RHostResolver
 RHostResolver hr;
 TInt res = false;
 TBool ret;

 RSocketServ socketServer;
 User::LeaveIfError(socketServer.Connect());        
 CleanupClosePushL(socketServer);

 TProtocolDesc pInfo;
 //_LIT(KL2Cap, "BTLinkManager");
 User::LeaveIfError(socketServer.FindProtocol(_L("BTLinkManager"),pInfo));

 res =  hr.Open(socketServer, KBTAddrFamily, pInfo.iProtocol);

 if (KErrNone != res) {
  // if not success, this means bluetooth is not on
  ret = EFalse;
 }

 else
 {
  ret = ETrue; // Bluetooth is already ON
  hr.Close();
 }

 CleanupStack::PopAndDestroy(1); 

 return ret;
}

 

或者

 

RSharedDataClient sd;
sd.Connect(0);
sd.Assign( TUid::Uid( 0x10005952 ) );

 

在3rd里可以这样做：

 

CRepository* cr = CRepository::NewLC( KCRUidBluetoothPowerState );
TInt value;
cr->Get( KBTPowerState, value );
if(value==EBTPowerOn)
    aPower=1;
CleanupStack::PopAndDestroy( cr );

 

注意：一定要在IDE中设置好3rd API的相关权限，否则会得到-46的错误代码，表示没有权限调用Get函数。

 

开启蓝牙

 

1. 弹出用户确认对话框的方式

头文件中：

RNotifier iNotifier;
 TBTDeviceResponseParamsPckg iNotifierResult;
 TPckgBuf<TBool> pckg;

 

CPP中：

User::LeaveIfError( iNotifier.Connect() );
iNotifier.StartNotifierAndGetResponse(  iStatus,
      KPowerModeSettingNotifierUid,
      pckg,
      iNotifierResult );

 iState = EOpeningBT; 
 SetActive();

 

2.不经过用户确认，自动打开蓝牙

 

对SDK 1.2中的bteng.llib进行reverse engineering，然后使用其中的CBTMCMSettings类

 // turn on Bluetooth in case it was off

CBTMCMSettings settings= CBTMCMSettings::NewL( (MBTMCMSettingsCB*)NULL );  
settings->SetPowerStateL(ETrue,EFalse ); // on, off is (EFalse,EFalse)

 

在3rd中，还有一种办法，理论上也可以开启蓝牙，但由于权限不够，在真机上没有测试成功。

CRepository* cr = CRepository::NewLC( KCRUidBluetoothPowerState );
TInt err = cr->Set(KBTPowerState,EBTPowerOn);

此时在真机上err的值为-46表示没有权限。