用枚举填充 QMenu

Question

我有一些struct与enum和std::string，我曾经使用for()循环填充QComboBoxes。像这样：

struct Struct
{
enum Enum
{
ENTRY1,
ENTRY2,
...
ENTRY_ALL
};
std::string names[ENTRY_ALL] {...};
};
for(int i=0; i<Struct::ENTRY_ALL; ++i)
comboBox->insertItem(i, names[i].c_str());

它奏效了，但鉴于最近的进展，我需要更多的条目、更多的struct、更多的组合框，而且它变得丑陋，所以我决定改用QMenu。

查看文档和示例，我发现我必须为每个条目提供一个connect()，为每个条目提供一个QAction，等等，如果我的enum很大，这就会成为一个问题，所以我想知道是否有办法自动化这个过程。

我的问题主要来自为什么我只需要每个QComboBox一个connect()，QComboBoxes 如何知道，如果我填写它们，哪个条目做什么？

---

如果有帮助，这是一些虚假的代码，从这里和那里，我所拥有的：

// tank class, header:
class Class
{
private:
// main entries
struct MainStruct
{
enum Enum {MAIN1, MAIN2, MAIN3, MAIN_ALL};
std::string names[MAIN_ALL] {"Main 1", "Main 2", "Main 3"};
};
// secondary entries
struct SubStruct
{
enum Enum {SUB1, SUB2, SUB3, SUB_ALL};
std::string names[SUB_ALL] {"Sub 1", "Sub 2", "Sub 3"};
};
// family of entries for SUB2
struct FamStruct
{
enum Enum {FAM1, FAM2, FAM3, FAM_ALL};
std::string names[FAM_ALL] {"Fam 1", "Fam 2", "Fam 3"};
}
public:
MainStruct mainEntries;
SubStruct subEntries;
FamStruct famEntries;
};
// inside the main window, there was a QComboBox doing this:
// header
QComboBox *cbMain, *cbSub, *cbFam;
// source
Class cls {Class()};
cbMain = new QComboBox; // same for cbSub, cbFam
// retranslateUi() (manually edited, not automatic), called each time the menu was clicked
void MainApp::retranslateUi()
{
cbMain.clear();
for(unsigned char i=0; i<cls.mainEntries.MAIN_ALL; ++i)
{
cbMain->insertItem(i, tr(cls.mainEntries.names[i].c_str()) );
cbMain->setItemData(i, tr(cls.mainEntries.tooltips[i].c_str()), Qt::ToolTipRole);
}
// same for cbSub, cbFam
}
// a function that did what was supposed to do when a combo box entry was clicked
void MainApp::func() { /* execution with variables changed by the combo */ }
/* There were additional functions taking care of the rest.
* Whenever an entry from the combo was clicked, somehow it "knew" that the entry was
* changed and func(), when executed, it ran with the variables changed by combo.
*/
void MainApp::updateSub()
{
switch(cbMain->currentIndex())
{
case cls.mainEntries.MAIN1: /*subentry stuff*/ break;
case cls.mainEntries.MAIN2: /*subentry stuff*/ break;
case cls.mainEntries.MAIN3: /*subentry stuff*/ break;
}
}
void MainApp::updateFam()
{
switch(cbSub->currentIndex())
{
case cls.subEntries.SUB1: /*fam entry stuff*/ break;
case cls.subEntries.SUB2: /*fam entry stuff*/ break;
case cls.subEntries.SUB3: /*fam entry stuff*/ break;
}
}
/* The connect() were attached to specific combos. When an entry in cbMain was
* clicked, cbSub and cbFam were properly updated and func() was run with
* the proper values, when cbSub was clicked, cbFam was updated and func()
* was run accordingly. Similar to an instant refresh.
*/
connect(cbMain, SIGNAL(activated(int)), this, SLOT(retranslateUi()));
connect(cbMain, SIGNAL(activated(int)), this, SLOT(updateSub()));
connect(cbMain, SIGNAL(activated(int)), this, SLOT(func()));
connect(cbSub, SIGNAL(activated(int)), this, SLOT(updateFam()));
connect(cbSub, SIGNAL(activated(int)), this, SLOT(func()));
connect(cbFam, SIGNAL(activated(int)), this, SLOT(func()));

每当我必须为子菜单添加新的条目族，甚至是带有子条目的主菜单时，事情都会变得复杂，所以我认为这样的菜单：

Menu:   Submenu:                AnotherSubmenu:
menu 1  submenu 1               altsub 1
menu 2  submenu 2 > family 1    altsub 2
menu 3  submenu 3   family 2    ...
family 3

会更好地工作，使事情整洁。Menu中的条目称为适当的Submenu，它有自己的Family，无论它们在哪里，Submenu可以调用另一个级别的AnotherSubmenu，等等。

Answer 1

您可以将所有QAction的触发信号连接到同一个插槽，并能够将对象与sender()一起使用，并将其转换为带有qobject_cast<>的QAction对象类型。

此外，如果您想使用索引，我们可以使用setObjectName()和objectName()

void {your Widget}::createAction()
QMenu *menu = new QMenu(this);
for(int i=0; i < 10; ++i){
QAction *action = new QAction(QString("action %1").arg(i));
action->setObjectName(QString("%1").arg(i));
connect(action, &QAction::triggered, this, &{your Widget}::onTriggeredAction);
menu->addAction(action);
}
}
void {your Widget}::onTriggeredAction()
{
QAction *obj = qobject_cast<QAction *>(sender());
int index = obj->objectName().toInt();
qDebug()<<index;
}