从extenionplugin的C++ 模块中读取数据并显示到Qt的ListView上 - c++编程基础

这次加载的数据来自于C++动态库而不是另一个qml文件。这个比之前的文章复杂。

我的项目目录树如下：

/listview2$ tree
.
├── imports
│   └── mylist
│       ├── libmylist.so
│       └── qmldir
├── list2.pro
├── plugin.cpp
├── run.sh
└── test.qml

The list2.pro文件内容如下：

TEMPLATE = lib
CONFIG += plugin
QT += qml
DESTDIR = imports/mylist
TARGET  = mylist
SOURCES += plugin.cpp
qml.files = test.qml
qml.path += ./
pluginfiles.files += imports/mylist/qmldir
pluginfiles.path += imports/mylist
target.path += imports/mylist
INSTALLS += target qml pluginfiles

模块目录下的qmldir做了修改：

module mylist
plugin mylist

为了方便，我在一个plugin.cpp文件中实现了所有的C++代码。

#include 
  
   
#include 
   
     #include 
    
      #include 
     
       #include 
      
        #include 
       
         #include 
        
          #include 
         
           class People { public: People(QString const & name, QString const & number) : name_(name), number_(number) { } QString name() const { return name_; } QString number() const { return number_; } private: QString name_; QString number_; }; class PeopleListModel : public QAbstractListModel { Q_OBJECT public: enum PeopleRoles { NameRole = Qt::UserRole + 1, NumberRole }; PeopleListModel(QObject * parent = 0) : QAbstractListModel(parent) { People p1("Dean", "186***"); addPeople(p1); People p2("Crystal", "186***"); addPeople(p2); } void addPeople(People const & p) { beginInsertRows(QModelIndex(), rowCount(), rowCount()); values_ << p; endInsertRows(); } int rowCount(QModelIndex const & parent = QModelIndex()) const { return values_.count(); } QVariant data(QModelIndex const & index, int role = Qt::DisplayRole) const { if (index.row() < 0 || index.row() >= values_.count()) return QVariant(); People const & p = values_[index.row()]; if (role == NameRole) return p.name(); else if (role == NumberRole) return p.number(); return QVariant(); } protected: QHash
          
            roleNames() const { QHash
           
             roles; roles[NameRole] = "name"; roles[NumberRole] = "number"; return roles; } private: QList
            
              values_; }; class QExampleQmlPlugin : public QQmlExtensionPlugin { Q_OBJECT Q_PLUGIN_METADATA(IID "org.qt-project.Qt.QQmlExtension.PeopleListModel") public: void registerTypes(char const * uri) { qmlRegisterType
             
              (uri, 1, 0, "PeopleListModel"); } }; #include "plugin.moc"

People类很简单，只包含了两个属性: name和number

PeopleListModel类继承自QAbstractListModel, 它提供了ListView需要的数据。

QExampleQmlPlugin类是plugin类，注册了PeopleListModel类。

注意PeopleListModel类的三个方法：rowCount, data和roleNames. 它们都是ListView需要的。

要想理解Model-View体系结构，请从下面的文档开始。

http://doc-snapshot.qt-project.org/qdoc/model-view-programming.html#introduction-to-model-view-programming