VS 2010 Qt 加载项中的链接错误

Question

我在Visual Studio 2010中使用Qt时遇到了一些问题。我已经从这个网站下载了qt二进制文件，版本Qt-4.7.3-dev-msvc2010-rdh。这段代码可以毫无问题地进行编译。

class Widget : public QWidget
{
    Q_OBJECT
public:
    Widget(QWidget* parent);
protected:
     void paintEvent(QPaintEvent *e);
private:
};

当我添加此行时：

void keyPressEvent(QKeyEvent *e);

发生此错误

1>------ Build started: Project: lol, Configuration: Release Win32 ------
1>Build started 25/09/2012 21:04:40.
1>InitializeBuildStatus:
1>  Creating "Releaselol.unsuccessfulbuild" because "AlwaysCreate" was specified.
1>CustomBuild:
1>  Moc'ing lol.h...
1>ClCompile:
1>  All outputs are up-to-date.
1>  moc_lol.cpp
1>  lol.cpp
1>  main.cpp
1>  Generating Code...
1>lol.obj : error LNK2001: unresolved external symbol "protected: virtual void __thiscall lol::mousePressEvent(class QMouseEvent *)" (?mousePressEvent@lol@@MAEXPAVQMouseEvent@@@Z)
1>C:UsersVTMDocumentsVisual Studio 2010ProjectsTCWin32Release\lol.exe : fatal error LNK1120: 1 unresolved externals
1>
1>Build FAILED.
1>
1>Time Elapsed 00:00:04.68
========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========

Answer 1

链接器似乎无法找到 keyPressEvent 实现。您是否在 Widget 类中实现了 keyPressEvent（）？您必须这样做，因为您在类定义中声明了这一点。添加以下代码只是为了将事件转发到基类。

void Widget::keyPressEvent(QKeyEvent *e){ QWidget::keyPressEvent(e);}