如何在C++中爲子類創建指針？

當我指向一個API的子類時，我遇到了一些麻煩。如何在C++中爲子類創建指針？

這裏是什麼我試圖做原來的PASCAL代碼：

Adapter:=TJBluetoothAdapter.JavaClass.getDefaultAdapter; 
    remoteDevice:=Adapter.getRemoteDevice(stringtojstring(targetMACAddress)); 
    sock:=remoteDevice.createRfcommSocketToServiceRecord(UID);

減少它的版本：

sock:=TJBluetoothAdapter.JavaClass.getDefaultAdapter.getRemoteDevice(stringtojstring(targetMACAddress)).createRfcommSocketToServiceRecord(UID);

這裏我有什麼，我已經嘗試過的事情：

_di_JBluetoothSocket* sock = new _di_JBluetoothSocket; 
    sock = &TJBluetoothAdapter::JavaClass->getDefaultAdapter()->getRemoteDevice(StringToJString(targetMACAddress))->createRfcommSocketToServiceRecord(uid);

和：

TJBluetoothAdapter::JavaClass->getDefaultAdapter()->getRemoteDevice(StringToJString(targetMACAddress))->createRfcommSocketToServiceRecord(uid)* sock;

和：

TJBluetoothAdapter* sock; 
    sock = TJBluetoothAdapter::JavaClass->getDefaultAdapter()->getRemoteDevice(StringToJString(targetMACAddress))->createRfcommSocketToServiceRecord(uid);

compilling時，不過，我總是得到錯誤，我應該怎麼辦？從現在起，感謝您的建議。

來源

2015-04-06 mauroaraujo

你什麼錯誤？忽略這一點並不是很有幫助。 – tadman

這是哪一種語言？在C++語言中沒有'：='操作符。也許BNF？ –

正如我在問題中所說的，第一個和第二個片段最初是Pascal – mauroaraujo

您聲明正確地顯示您的sock變量。不要聲明類型爲_di_...的指針。它已經是一個指針（更具體地說，它是一個System::DelphiInterface類的typedef，它是Delphi接口指針的C++ smart pointer包裝器）。

_di_JBluetoothAdapter Adapter = TJBluetoothAdapter::JavaClass->getDefaultAdapter(); 
_di_JBluetoothDevice remoteDevice = Adapter->getRemoteDevice(StringToJString(targetMACAddress)); 
_di_JBluetoothSocket sock = remoteDevice->createRfcommSocketToServiceRecord(UID);

這大致相當於此：

JBluetoothAdapter *Adapter = TJBluetoothAdapter::JavaClass->getDefaultAdapter(); 
Adapter->AddRef(); 

JBluetoothDevice *remoteDevice = Adapter->getRemoteDevice(StringToJString(targetMACAddress)); 
remoteDevice->AddRef(); 

JBluetoothSocket *sock = remoteDevice->createRfcommSocketToServiceRecord(UID); 
sock->AddRef(); 

... 

sock->_Release(); 
remoteDevice->_Release(); 
Adapter->_Release();

來源

2015-04-06 17:59:37

如何在C++中爲子類創建指針？

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