这个错误产生的原因通常是,你报错的地方使用了一个结构体,而这个结构体对于这个地方不可见 解决方案:把这个结构体的声明/头函数 include 进来,就可以了
Qt头文件引用其他类,主类头文件报错(1)invalid use of incomplete type 'class xx::yy' (2)forward declaration of 'class xx::yy' 其实这个错误很蠢,由于代码是从cpp文件直接copy过来的就没仔细看,但是他这个报错很有迷惑性,我们来看图: 就这行代码,从cpp文件中复制过来的: 本来目的呢就是提升这个变量的作...
Now, what I did is I created a mainwindow in Qt designer, then I added a second form to the project , which will be the second dialog window when a button clicked. Because I created the form manually "mydialog.ui", I added class "mydialog.h and mydialog.cpp" and put the heade...
Qt开发,从数据库中查询,在遍历结果集时,代码报错: invalid use of incomplete type ‘class QVariant’ 说是QVariant类的用法不对. QString sql = "select * from sysuser"; QSqlQuery query; query.exec(sql); while(query.next()){ QString id = query.value("id").toString(); //报错 ...
finddialog.cpp:50:25: error: invalid use of incomplete type ‘classQLineEdit’ QString text = lineEdit->text(); ^ In file included from finddialog.cpp:3:0: finddialog.h:8:7: error: forward declaration of ‘classQLineEdit’classQLineEdit; ...
Qt 报错:invalid use of incomplete type ‘class QDesktopWidget’,QtDemo,原来项目可以正常运行.进过了一些修改和窗体的调整,再次运行提示:invaliduseofincompletetype‘classQDesktopWidget’提示比较怪异,一时看不出什么原因.探索一番,找到了答案,其实就是修改之后,内
error: invalid use of incomplete type 'class Ui::AddDialog' error: forward declaration of 'class Ui::AddDialog' 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 #ifndef ADDDIALOG_H#define ADDDIALOG_H#include <QDialog>namespaceUi {classAddDialog; }classAddDialog :...
今天在写奥特曼打大怪兽的时候,发现一个奇怪的问题,我定义了两个基类Ultraman和Monster,一个Monster的子类Boss,然后两个基类是有相互勾结的地方,它们都或多或少的使用了对方的类型进行定义自己,然后我在第一个类实现前面进行了另一个类的声明:
include "iostream"//classA中用到了classB的成员，所以classB要放到classA之前class B {public:void B_func() {std::cout << "sml" << std::endl;}};class A {public:void func(B* para) {para -> B_func();}};int main() {B* T1 = new B();A* T2 =new A();T2 -> ...