使用 QQmlListProperty 在 Qml 中显示和修改 QList

Use QQmlListProperty to show and modify QList in Qml

本文关键字:修改 QList 显示 QQmlListProperty Qml 使用      更新时间:2023-10-16

再次,我有一个问题(也许是一个问题(,我在Qt5中使用Qt和QML制作了一个程序,并使用QTQUICK 2.0的QML制作了一个程序,我有一个C ++模型qlist,我需要在运行时修改列表,我使用q QQmlListProperty并在qml中显示项目,但是在我添加或删除代码的那一刻,它们没有隐藏和显示是下一个:

class ConceptsList: public QObject{ 
 Q_OBJECT
 Q_PROPERTY(QQmlListProperty<Concept> concepts READ concepts NOTIFY conceptsChanged) 
 Q_CLASSINFO("DefaultProperty", "concepts")
 public:
  ConceptsList(QObject *parent=0);
  QQmlListProperty<Concept> concepts();
  Q_INVOKABLE static void append_concept(QQmlListProperty<Concept> *list, Concept *cpt);
  Q_INVOKABLE void removeConcept(int index);
  Q_INVOKABLE void addConcept(QString m_id,QString description, QString quantity, QString price, QString unit, QString total);
  Q_INVOKABLE int countConcepts();
  static void clearConcepts(QQmlListProperty<Concept> *property);
  static int conceptsSize(QQmlListProperty<Concept> *property);
  static Concept *conceptAt(QQmlListProperty<Concept> *property, int index);
 signals:
  void conceptsChanged();
 private:
  QList<Concept *> m_concepts;
}

使用列表视图和委托,我没有问题要查看,但我的问题是我是否可以使用 QQmlListProperty 并修改 Qlist,或者我将更改一个表单以将 qlist 公开给 qml,如果有可能如何从 qml 调用该方法,或者如何在C++中实现,我问是因为存在很少的数量或示例与工作这种形式。在QML中,我的代码是下一个:

    ConceptsList{
        id:cpts
        concepts:[
           Concept{
                m_id:"7"
                m_quantity: "3"
                m_price: "1"
                m_unit:"1"
                m_description:"algo"
                m_total:"2"
            }
        ]
    }
    ListView {
            id: listConceptsView
            objectName: "list"
            anchors.fill: parent
            anchors.margins: 5
            clip: true
            focus: true
            highlight: highlightBar
            highlightFollowsCurrentItem: false

            Component{
                id: tableConceptDelegate
                Item{
                    anchors.margins: 4
                    width: 515
                    height: 27
                    clip: true
                    Row {
                        spacing: 4
                        Text {
                            height: 26; width: 76
                            text: model.m_id
                            color: "black"
                            font.bold: true
                            horizontalAlignment: Text.AlignHCenter
                        }
                        ...
                        ...
                        Text {
                            height: 26; width: 120
                            text: model.m_total//amountTotal
                            color: "black"
                            font.bold: true
                            horizontalAlignment: Text.AlignHCenter
                        }
                    }
                    MouseArea {
                        id: mouse_area1
                        anchors.fill: parent
                        onClicked:
                        {
                            listConceptsView.currentIndex = index
                        }
                    }
                }
            }
            delegate: tableConceptDelegate
            model:cptCpt // i define this alias how cptCpt: cpt.concepts
        }

我自己得到了答案,首先,我停止在方法中使用属性Q_INVOCABLE append_concept,其次,我在addConcept的实现中添加了一行代码。这是代码:

以前:

Q_INVOKABLE static void append_concept(QQmlListProperty<Concept> *list, Concept *cpt);

现在:

static void append_concept(QQmlListProperty<Concept> *list, Concept *cpt);

也许这不会影响,但我宁愿不冒险。

addConceptremoveConcept的实现中:

 void ConceptsList::addConcept(QString m_id, QString quantity, QString price, QString unit, QString description)
 {
   Concept *cpt=new Concept(m_id, quantity, unit, price, description);
   m_concepts.append(cpt); 
   this->conceptsChanged();
 }
void ConceptsList::removeConcept(int index)
{
  m_concepts.removeAt(index);
  this->conceptsChanged();
}