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QT信号槽报错no matching member function for call to 'connect'

发布时间 2023-06-21 17:13:01作者: 3的4次方

QT信号槽报错no matching member function for call to 'connect'

问题

connect(dynamic_cast<AnalyseWindow*>(parent),&AnalyseWindow::sigStart,timerRefresh,&QTimer::start,Qt::DirectConnection);

报错信息：

chartform.cpp:59:5: error: no matching member function for call to 'connect'
qobject.h:222:36: note: candidate function not viable: no known conversion from 'void (AnalyseWindow::*)()' to 'const char *' for 2nd argument
qobject.h:225:36: note: candidate function not viable: no known conversion from 'void (AnalyseWindow::*)()' to 'const QMetaMethod' for 2nd argument
qobject.h:242:43: note: candidate template ignored: couldn't infer template argument 'Func2'
qobject.h:283:13: note: candidate template ignored: couldn't infer template argument 'Func2'
qobject.h:322:13: note: candidate template ignored: couldn't infer template argument 'Func2'
qobject.h:274:13: note: candidate function template not viable: requires 3 arguments, but 5 were provided
qobject.h:314:13: note: candidate function template not viable: requires 3 arguments, but 5 were provided
qobject.h:481:41: note: candidate function not viable: requires at most 4 arguments, but 5 were provided

原因

有多种：

  1. 参数不是继承自 QObject 的对象，或者没有导入 Qt 命名空间。
  2. 信号和槽的参数列表不匹配。信号的参数个数 >= 槽的参数个数且信号和槽的参数类型也必须匹配
  3. 函数指针类型不匹配。
  4. 在进行 connect 连接时，有可能会遇到无法匹配的候选函数。在这种情况下，可以通过使用 QObject::connect 函数的第五个参数，来强制选择合适的函数。