我正在扩展一个抽象类，覆盖纯虚方法，但是当我编译时我仍然会收到错误：
无法分配抽象类型的对象，因为以下虚函数在'CefRequestHandler :: MyResourceHandler'中是纯粹的
错误消息中的函数来自我扩展的类的父类。为什么会这样？为什么它从我的扩展类的父类中提取纯虚方法？我怎么能绕过这个？
如果有帮助，我没有做任何事情来覆盖我班级中的方法，基本上将它们列在我的班级中，而不是在他们面前写下虚拟。见下文。
我用来返回班级的方法：
virtual CefRefPtr<CefResourceHandler> GetResourceHandler(
CefRefPtr<CefBrowser> browser,
CefRefPtr<CefFrame> frame,
CefRefPtr<CefRequest> request) {
//return NULL;
return new MyResourceHandler();
}
包含方法的类：
class CefRequestCallback : public virtual CefBase {
public:
///
// Continue the url request. If |allow| is true the request will be continued.
// Otherwise, the request will be canceled.
///
/*--cef(capi_name=cont)--*/
virtual void Continue(bool allow) =0;
///
// Cancel the url request.
///
/*--cef()--*/
virtual void Cancel() =0;
};
///
// Implement this interface to handle events related to browser requests. The
// methods of this class will be called on the thread indicated.
///
/*--cef(source=client)--*/
class CefRequestHandler : public virtual CefBase {
public:
typedef cef_return_value_t ReturnValue;
typedef cef_termination_status_t TerminationStatus;
typedef cef_urlrequest_status_t URLRequestStatus;
typedef cef_window_open_disposition_t WindowOpenDisposition;
///
// Called on the UI thread before browser navigation. Return true to cancel
// the navigation or false to allow the navigation to proceed. The |request|
// object cannot be modified in this callback.
// CefLoadHandler::OnLoadingStateChange will be called twice in all cases.
// If the navigation is allowed CefLoadHandler::OnLoadStart and
// CefLoadHandler::OnLoadEnd will be called. If the navigation is canceled
// CefLoadHandler::OnLoadError will be called with an |errorCode| value of
// ERR_ABORTED.
///
/*--cef()--*/
virtual bool OnBeforeBrowse(CefRefPtr<CefBrowser> browser,
CefRefPtr<CefFrame> frame,
CefRefPtr<CefRequest> request,
bool is_redirect) {
return false;
}
///
// Called on the UI thread before OnBeforeBrowse in certain limited cases
// where navigating a new or different browser might be desirable. This
// includes user-initiated navigation that might open in a special way (e.g.
// links clicked via middle-click or ctrl + left-click) and certain types of
// cross-origin navigation initiated from the renderer process (e.g.
// navigating the top-level frame to/from a file URL). The |browser| and
// |frame| values represent the source of the navigation. The
// |target_disposition| value indicates where the user intended to navigate
// the browser based on standard Chromium behaviors (e.g. current tab,
// new tab, etc). The |user_gesture| value will be true if the browser
// navigated via explicit user gesture (e.g. clicking a link) or false if it
// navigated automatically (e.g. via the DomContentLoaded event). Return true
// to cancel the navigation or false to allow the navigation to proceed in the
// source browser's top-level frame.
///
/*--cef()--*/
virtual bool OnOpenURLFromTab(CefRefPtr<CefBrowser> browser,
CefRefPtr<CefFrame> frame,
const CefString& target_url,
WindowOpenDisposition target_disposition,
bool user_gesture) {
return false;
}
///
// Called on the IO thread before a resource request is loaded. The |request|
// object may be modified. Return RV_CONTINUE to continue the request
// immediately. Return RV_CONTINUE_ASYNC and call CefRequestCallback::
// Continue() at a later time to continue or cancel the request
// asynchronously. Return RV_CANCEL to cancel the request immediately.
//
///
/*--cef(default_retval=RV_CONTINUE)--*/
virtual ReturnValue OnBeforeResourceLoad(
CefRefPtr<CefBrowser> browser,
CefRefPtr<CefFrame> frame,
CefRefPtr<CefRequest> request,
CefRefPtr<CefRequestCallback> callback) {
return RV_CONTINUE;
}
///
// Called on the IO thread before a resource is loaded. To allow the resource
// to load normally return NULL. To specify a handler for the resource return
// a CefResourceHandler object. The |request| object should not be modified in
// this callback.
///
/*--cef()--*/
***virtual CefRefPtr<CefResourceHandler> GetResourceHandler(
CefRefPtr<CefBrowser> browser,
CefRefPtr<CefFrame> frame,
CefRefPtr<CefRequest> request) {
//return NULL;
return new MyResourceHandler();
}***
class MyResourceHandler : public CefResourceHandler
{
public:
MyResourceHandler()
//offset_(0)
{}
bool ProcessRequest(CefRefPtr<CefRequest> request,
CefRefPtr<CefCallback> callback) ;
void GetResponseHeaders(CefRefPtr<CefResponse> response,
int64& response_length,
CefString& redirectUrl) ;
bool ReadResponse(void* data_out,
int bytes_to_read,
int& bytes_read,
CefRefPtr<CefCallback> callback) ;
bool CanGetCookie(const CefCookie& cookie) { return true; }
bool CanSetCookie(const CefCookie& cookie) { return true; }
void Cancel() ;
// bool ProcessRequest (CefRefPtr<CefRequest> request,
//CefRefPtr<CefCallback> callback){
//CefRefPtr<CefRequest> cef = CefRequest::Create();
//cef = request;
//CefRequest::ReferrerPolicy origin = REFERRER_POLICY_ALWAYS;
//request->SetReferrer("www.google.com",origin);
//cef->SetReferrer("www.google.com",origin);
//}
//IMPLEMENT_REFCOUNTING(MyResourceHandler);
//IMPLEMENT_LOCKING(MyResourceHandler);
};
///
// Called on the IO thread when a resource load is redirected. The |request|
// parameter will contain the old URL and other request-related information.
// The |new_url| parameter will contain the new URL and can be changed if
// desired. The |request| object cannot be modified in this callback.
///
/*--cef()--*/
virtual void OnResourceRedirect(CefRefPtr<CefBrowser> browser,
CefRefPtr<CefFrame> frame,
CefRefPtr<CefRequest> request,
CefString& new_url) {}
///
// Called on the IO thread when a resource response is received. To allow the
// resource to load normally return false. To redirect or retry the resource
// modify |request| (url, headers or post body) and return true. The
// |response| object cannot be modified in this callback.
///
/*--cef()--*/
virtual bool OnResourceResponse(CefRefPtr<CefBrowser> browser,
CefRefPtr<CefFrame> frame,
CefRefPtr<CefRequest> request,
CefRefPtr<CefResponse> response) {
return false;
}
///
// Called on the IO thread to optionally filter resource response content.
// |request| and |response| represent the request and response respectively
// and cannot be modified in this callback.
///
/*--cef()--*/
virtual CefRefPtr<CefResponseFilter> GetResourceResponseFilter(
CefRefPtr<CefBrowser> browser,
CefRefPtr<CefFrame> frame,
CefRefPtr<CefRequest> request,
CefRefPtr<CefResponse> response) {
return NULL;
}
///
// Called on the IO thread when a resource load has completed. |request| and
// |response| represent the request and response respectively and cannot be
// modified in this callback. |status| indicates the load completion status.
// |received_content_length| is the number of response bytes actually read.
///
/*--cef()--*/
virtual void OnResourceLoadComplete(CefRefPtr<CefBrowser> browser,
CefRefPtr<CefFrame> frame,
CefRefPtr<CefRequest> request,
CefRefPtr<CefResponse> response,
URLRequestStatus status,
int64 received_content_length) {}
///
// Called on the IO thread when the browser needs credentials from the user.
// |isProxy| indicates whether the host is a proxy server. |host| contains the
// hostname and |port| contains the port number. |realm| is the realm of the
// challenge and may be empty. |scheme| is the authentication scheme used,
// such as "basic" or "digest", and will be empty if the source of the request
// is an FTP server. Return true to continue the request and call
// CefAuthCallback::Continue() either in this method or at a later time when
// the authentication information is available. Return false to cancel the
// request immediately.
///
/*--cef(optional_param=realm,optional_param=scheme)--*/
virtual bool GetAuthCredentials(CefRefPtr<CefBrowser> browser,
CefRefPtr<CefFrame> frame,
bool isProxy,
const CefString& host,
int port,
const CefString& realm,
const CefString& scheme,
CefRefPtr<CefAuthCallback> callback) {
return false;
}
///
// Called on the IO thread when JavaScript requests a specific storage quota
// size via the webkitStorageInfo.requestQuota function. |origin_url| is the
// origin of the page making the request. |new_size| is the requested quota
// size in bytes. Return true to continue the request and call
// CefRequestCallback::Continue() either in this method or at a later time to
// grant or deny the request. Return false to cancel the request immediately.
///
/*--cef()--*/
virtual bool OnQuotaRequest(CefRefPtr<CefBrowser> browser,
const CefString& origin_url,
int64 new_size,
CefRefPtr<CefRequestCallback> callback) {
return false;
}
///
// Called on the UI thread to handle requests for URLs with an unknown
// protocol component. Set |allow_os_execution| to true to attempt execution
// via the registered OS protocol handler, if any.
// SECURITY WARNING: YOU SHOULD USE THIS METHOD TO ENFORCE RESTRICTIONS BASED
// ON SCHEME, HOST OR OTHER URL ANALYSIS BEFORE ALLOWING OS EXECUTION.
///
/*--cef()--*/
virtual void OnProtocolExecution(CefRefPtr<CefBrowser> browser,
const CefString& url,
bool& allow_os_execution) {}
///
// Called on the UI thread to handle requests for URLs with an invalid
// SSL certificate. Return true and call CefRequestCallback::Continue() either
// in this method or at a later time to continue or cancel the request. Return
// false to cancel the request immediately. If
// CefSettings.ignore_certificate_errors is set all invalid certificates will
// be accepted without calling this method.
///
/*--cef()--*/
virtual bool OnCertificateError(
CefRefPtr<CefBrowser> browser,
cef_errorcode_t cert_error,
const CefString& request_url,
CefRefPtr<CefSSLInfo> ssl_info,
CefRefPtr<CefRequestCallback> callback) {
return false;
}
///
// Called on the browser process UI thread when a plugin has crashed.
// |plugin_path| is the path of the plugin that crashed.
///
/*--cef()--*/
virtual void OnPluginCrashed(CefRefPtr<CefBrowser> browser,
const CefString& plugin_path) {}
///
// Called on the browser process UI thread when the render view associated
// with |browser| is ready to receive/handle IPC messages in the render
// process.
///
/*--cef()--*/
virtual void OnRenderViewReady(CefRefPtr<CefBrowser> browser) {}
///
// Called on the browser process UI thread when the render process
// terminates unexpectedly. |status| indicates how the process
// terminated.
///
/*--cef()--*/
virtual void OnRenderProcessTerminated(CefRefPtr<CefBrowser> browser,
TerminationStatus status) {}
};
以下是我创建的导致错误的类：
class MyResourceHandler : public CefResourceHandler
{
public:
MyResourceHandler()
//offset_(0)
{}
bool ProcessRequest(CefRefPtr<CefRequest> request,
CefRefPtr<CefCallback> callback) ;
void GetResponseHeaders(CefRefPtr<CefResponse> response,
int64& response_length,
CefString& redirectUrl) ;
bool ReadResponse(void* data_out,
int bytes_to_read,
int& bytes_read,
CefRefPtr<CefCallback> callback) ;
bool CanGetCookie(const CefCookie& cookie) { return true; }
bool CanSetCookie(const CefCookie& cookie) { return true; }
void Cancel() ;
};
CEFResourceHandler类（I类扩展）：
#ifndef CEF_INCLUDE_CEF_RESOURCE_HANDLER_H_
#define CEF_INCLUDE_CEF_RESOURCE_HANDLER_H_
#pragma once
#include "include/cef_base.h"
#include "include/cef_browser.h"
#include "include/cef_callback.h"
#include "include/cef_cookie.h"
#include "include/cef_request.h"
#include "include/cef_response.h"
///
// Class used to implement a custom request handler interface. The methods of
// this class will always be called on the IO thread.
///
/*--cef(source=client)--*/
class CefResourceHandler : public virtual CefBase {
public:
///
// Begin processing the request. To handle the request return true and call
// CefCallback::Continue() once the response header information is available
// (CefCallback::Continue() can also be called from inside this method if
// header information is available immediately). To cancel the request return
// false.
///
/*--cef()--*/
virtual bool ProcessRequest(CefRefPtr<CefRequest> request,
CefRefPtr<CefCallback> callback) =0;
///
// Retrieve response header information. If the response length is not known
// set |response_length| to -1 and ReadResponse() will be called until it
// returns false. If the response length is known set |response_length|
// to a positive value and ReadResponse() will be called until it returns
// false or the specified number of bytes have been read. Use the |response|
// object to set the mime type, http status code and other optional header
// values. To redirect the request to a new URL set |redirectUrl| to the new
// URL.
///
/*--cef()--*/
virtual void GetResponseHeaders(CefRefPtr<CefResponse> response,
int64& response_length,
CefString& redirectUrl) =0;
///
// Read response data. If data is available immediately copy up to
// |bytes_to_read| bytes into |data_out|, set |bytes_read| to the number of
// bytes copied, and return true. To read the data at a later time set
// |bytes_read| to 0, return true and call CefCallback::Continue() when the
// data is available. To indicate response completion return false.
///
/*--cef()--*/
virtual bool ReadResponse(void* data_out,
int bytes_to_read,
int& bytes_read,
CefRefPtr<CefCallback> callback) =0;
///
// Return true if the specified cookie can be sent with the request or false
// otherwise. If false is returned for any cookie then no cookies will be sent
// with the request.
///
/*--cef()--*/
virtual bool CanGetCookie(const CefCookie& cookie) { return true; }
///
// Return true if the specified cookie returned with the response can be set
// or false otherwise.
///
/*--cef()--*/
virtual bool CanSetCookie(const CefCookie& cookie) { return true; }
///
// Request processing has been canceled.
///
/*--cef()--*/
virtual void Cancel() =0;
};
#endif // CEF_INCLUDE_CEF_RESOURCE_HANDLER_H_
注意在return语句中调用自定义类时错误是如何开始的。
错误信息输出：
In file included from /home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/include/cef_client.h:56:0,
from /home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/libcef_dll/ctocpp/browser_ctocpp.h:24,
from /home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/libcef_dll/cpptoc/context_menu_handler_cpptoc.cc:14:
/home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/include/cef_request_handler.h: In member function ‘virtual CefRefPtr<CefResourceHandler> CefRequestHandler::GetResourceHandler(CefRefPtr<CefBrowser>, CefRefPtr<CefFrame>, CefRefPtr<CefRequest>)’:
/home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/include/cef_request_handler.h:159:27: error: cannot allocate an object of abstract type ‘CefRequestHandler::MyResourceHandler’
return MyResourceHandler();
^
/home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/include/cef_request_handler.h:163:7: note: because the following virtual functions are pure within ‘CefRequestHandler::MyResourceHandler’:
class MyResourceHandler : public CefResourceHandler
^
In file included from /home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/include/cef_context_menu_handler.h:41:0,
from /home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/libcef_dll/cpptoc/context_menu_handler_cpptoc.h:21,
from /home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/libcef_dll/cpptoc/context_menu_handler_cpptoc.cc:13:
/home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/include/cef_base.h:60:16: note: virtual void CefBase::AddRef() const
virtual void AddRef() const =0;
^
/home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/include/cef_base.h:66:16: note: virtual bool CefBase::Release() const
virtual bool Release() const =0;
^
/home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/include/cef_base.h:71:16: note: virtual bool CefBase::HasOneRef() const
virtual bool HasOneRef() const =0;
^
In file included from /home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/include/cef_client.h:56:0,
from /home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/libcef_dll/cpptoc/client_cpptoc.h:21,
from /home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/libcef_dll/cpptoc/client_cpptoc.cc:13:
/home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/include/cef_request_handler.h: In member function ‘virtual CefRefPtr<CefResourceHandler> CefRequestHandler::GetResourceHandler(CefRefPtr<CefBrowser>, CefRefPtr<CefFrame>, CefRefPtr<CefRequest>)’:
/home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/include/cef_request_handler.h:159:27: error: cannot allocate an object of abstract type ‘CefRequestHandler::MyResourceHandler’
return MyResourceHandler();
^
/home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/include/cef_request_handler.h:163:7: note: because the following virtual functions are pure within ‘CefRequestHandler::MyResourceHandler’:
class MyResourceHandler : public CefResourceHandler
^
In file included from /home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/include/cef_client.h:41:0,
from /home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/libcef_dll/cpptoc/client_cpptoc.h:21,
from /home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/libcef_dll/cpptoc/client_cpptoc.cc:13:
/home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/include/cef_base.h:60:16: note: virtual void CefBase::AddRef() const
virtual void AddRef() const =0;
^
/home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/include/cef_base.h:66:16: note: virtual bool CefBase::Release() const
virtual bool Release() const =0;
^
/home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/include/cef_base.h:71:16: note: virtual bool CefBase::HasOneRef() const
virtual bool HasOneRef() const =0;
^
In file included from /home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/include/cef_client.h:56:0,
from /home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/libcef_dll/ctocpp/browser_ctocpp.h:24,
from /home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/libcef_dll/cpptoc/display_handler_cpptoc.cc:14:
/home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/include/cef_request_handler.h: In member function ‘virtual CefRefPtr<CefResourceHandler> CefRequestHandler::GetResourceHandler(CefRefPtr<CefBrowser>, CefRefPtr<CefFrame>, CefRefPtr<CefRequest>)’:
/home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/include/cef_request_handler.h:159:27: error: cannot allocate an object of abstract type ‘CefRequestHandler::MyResourceHandler’
return MyResourceHandler();
^
/home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/include/cef_request_handler.h:163:7: note: because the following virtual functions are pure within ‘CefRequestHandler::MyResourceHandler’:
class MyResourceHandler : public CefResourceHandler
^
In file included from /home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/include/cef_display_handler.h:41:0,
from /home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/libcef_dll/cpptoc/display_handler_cpptoc.h:21,
from /home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/libcef_dll/cpptoc/display_handler_cpptoc.cc:13:
/home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/include/cef_base.h:60:16: note: virtual void CefBase::AddRef() const
virtual void AddRef() const =0;
^
/home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/include/cef_base.h:66:16: note: virtual bool CefBase::Release() const
virtual bool Release() const =0;
^
/home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/include/cef_base.h:71:16: note: virtual bool CefBase::HasOneRef() const
virtual bool HasOneRef() const =0;
^
In file included from /home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/include/cef_client.h:56:0,
from /home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/libcef_dll/ctocpp/browser_ctocpp.h:24,
from /home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/libcef_dll/cpptoc/dialog_handler_cpptoc.cc:14:
/home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/include/cef_request_handler.h: In member function ‘virtual CefRefPtr<CefResourceHandler> CefRequestHandler::GetResourceHandler(CefRefPtr<CefBrowser>, CefRefPtr<CefFrame>, CefRefPtr<CefRequest>)’:
/home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/include/cef_request_handler.h:159:27: error: cannot allocate an object of abstract type ‘CefRequestHandler::MyResourceHandler’
return MyResourceHandler();
^
/home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/include/cef_request_handler.h:163:7: note: because the following virtual functions are pure within ‘CefRequestHandler::MyResourceHandler’:
class MyResourceHandler : public CefResourceHandler
^
In file included from /home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/include/cef_dialog_handler.h:41:0,
from /home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/libcef_dll/cpptoc/dialog_handler_cpptoc.h:21,
from /home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/libcef_dll/cpptoc/dialog_handler_cpptoc.cc:13:
/home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/include/cef_base.h:60:16: note: virtual void CefBase::AddRef() const
virtual void AddRef() const =0;
^
/home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/include/cef_base.h:66:16: note: virtual bool CefBase::Release() const
virtual bool Release() const =0;
^
/home/c/Downloads/cef_binary_3.2704.1432.g60b3718_linux64/include/cef_base.h:71:16: note: virtual bool CefBase::HasOneRef() const
virtual bool HasOneRef() const =0;
^
make[3]: *** [libcef_dll_wrapper/CMakeFiles/libcef_dll_wrapper.dir/cpptoc/context_menu_handler_cpptoc.cc.o] Error 1
make[3]: *** Waiting for unfinished jobs....
make[3]: *** [libcef_dll_wrapper/CMakeFiles/libcef_dll_wrapper.dir/cpptoc/display_handler_cpptoc.cc.o] Error 1
make[3]: *** [libcef_dll_wrapper/CMakeFiles/libcef_dll_wrapper.dir/cpptoc/client_cpptoc.cc.o] Error 1
make[3]: *** [libcef_dll_wrapper/CMakeFiles/libcef_dll_wrapper.dir/cpptoc/dialog_handler_cpptoc.cc.o] Error 1
make[2]: *** [libcef_dll_wrapper/CMakeFiles/libcef_dll_wrapper.dir/all] Error 2
make[1]: *** [cefsimple/CMakeFiles/cefsimple.dir/rule] Error 2
make: *** [cefsimple] Error 2
解决方案
我在MyResourceHandler课程中添加了以下内容。我不得不从父类重写纯虚函数：
void AddRef()const {} ;
bool Release() const { return true; }
bool HasOneRef() const { return true; };
答案 0 :(得分：1)
错误消息中的函数来自的父类 我升级了。为什么会这样？
这就是继承在C ++中的工作方式。如果类中包含任何纯虚函数，则该类是抽象的。从抽象类派生新类时，它会继承尚未覆盖的任何纯虚函数，从而使其也是抽象的。如果你需要能够实例化那个派生类，你必须实现任何剩下的纯虚函数，不仅是它的直接祖先类，还有它的祖先类，因为它们被继承到你的类中，仍然需要被定义。实例化的类不能有任何纯虚函数。
为什么从我的扩展类的父级中提取纯虚方法？
因为这就是C ++的工作方式。
我怎样才能解决这个问题？
您需要实现任何尚未在任何祖先类中重写的纯虚函数。
答案 1 :(得分：1)
OP发布的解决方案不正确，并且会泄漏内存，因为它没有实现这些功能。 CEF使用Reference Counting，这些方法是该实施的一部分，它们只是简单实施
使用提供的宏。
class MyClass : public CefBase {
public:
// Various class methods here...
private:
// Various class members here...
IMPLEMENT_REFCOUNTING(MyClass); // Provides atomic refcounting implementation.
};
// References a MyClass instance
CefRefPtr<MyClass> my_class = new MyClass();
https://bitbucket.org/chromiumembedded/cef/wiki/GeneralUsage.md#markdown-header-reference-counting