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Qt C++ 初始化一个 QStringList 类成员

[英]Qt C++ initialize a QStringList class member

原文 2012-05-22 11:41:56 0 1 c++/ qt/ qstring

I have a class member of type QStringList .我有一个QStringList类型的类成员。 I had a guess that when this class is instantiated, nex instance get such a QStringLsit with no elements in it.我有一个猜测，当这个类被实例化时， nex实例会得到这样一个没有元素的QStringLsit 。
I have a function that should fill in this QStringList on user interaction.我有一个函数应该在用户交互时填写这个QStringList 。 However, I see with debugger that class member does not exist at function call.但是，我在调试器中看到函数调用时不存在类成员。 What could it be all about?这到底是怎么回事？ Is there a way to initialize the QListString that I may be missing here?有没有办法初始化我可能在这里丢失的QListString ？

1 个解决方案

QStringList should get initialized on the creation of your object automatically (unless it is a pointer). QStringList应该在创建对象时自动初始化（除非它是指针）。 I see two possible explanations for the debugger's behaviour:对于调试器的行为，我看到了两种可能的解释：

Your object (of which you call the function) doesn't get created before the function call;您的对象（您调用该函数的对象）不会在函数调用之前创建； that means that the this pointer is invalid when the function gets entered.这意味着当函数进入时this指针是无效的。 This may be the case if you call the function on an uninitialised pointer to your class.如果您在指向您的类的未初始化指针上调用该函数，则可能就是这种情况。
The debugger just doesn't show the QStringList member correctly.调试器只是没有正确显示QStringList成员。
If your member is of type QStringList* (a pointer), it doesn't get automatically initialised on object creation.如果您的成员属于QStringList*类型（指针），则它不会在对象创建时自动初始化。 Then you'd need to do list = new QStringList();然后你需要做list = new QStringList(); in the constructor.在构造函数中。 But I doubt that you need a pointer to a string list here.但我怀疑您是否需要一个指向字符串列表的指针。