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QIdentityProxyModel Class

QIdentityProxyModel 类未修改地代理其源模型。更多

头文件： #include <QIdentityProxyModel>
CMake： find_package(Qt6 REQUIRED COMPONENTS Core)
target_link_libraries(mytarget PRIVATE Qt6::Core)
qmake： QT += core
继承： QAbstractProxyModel

公共函数

QIdentityProxyModel(QObject *parent = nullptr)
virtual ~QIdentityProxyModel()
(since 6.8) bool handleSourceDataChanges() const
(since 6.8) bool handleSourceLayoutChanges() const

重新实现的公共函数

virtual int columnCount(const QModelIndex &parent = QModelIndex()) const override
virtual bool dropMimeData(const QMimeData *data, Qt::DropAction action, int row, int column, const QModelIndex &parent) override
virtual QVariant headerData(int section, Qt::Orientation orientation, int role = Qt::DisplayRole) const override
virtual QModelIndex index(int row, int column, const QModelIndex &parent = QModelIndex()) const override
virtual bool insertColumns(int column, int count, const QModelIndex &parent = QModelIndex()) override
virtual bool insertRows(int row, int count, const QModelIndex &parent = QModelIndex()) override
virtual QModelIndex mapFromSource(const QModelIndex &sourceIndex) const override
virtual QItemSelection mapSelectionFromSource(const QItemSelection &selection) const override
virtual QItemSelection mapSelectionToSource(const QItemSelection &selection) const override
virtual QModelIndex mapToSource(const QModelIndex &proxyIndex) const override
virtual QModelIndexList match(const QModelIndex &start, int role, const QVariant &value, int hits = 1, Qt::MatchFlags flags = Qt::MatchFlags(Qt::MatchStartsWith|Qt::MatchWrap)) const override
virtual bool moveColumns(const QModelIndex &sourceParent, int sourceColumn, int count, const QModelIndex &destinationParent, int destinationChild) override
virtual bool moveRows(const QModelIndex &sourceParent, int sourceRow, int count, const QModelIndex &destinationParent, int destinationChild) override
virtual QModelIndex parent(const QModelIndex &child) const override
virtual bool removeColumns(int column, int count, const QModelIndex &parent = QModelIndex()) override
virtual bool removeRows(int row, int count, const QModelIndex &parent = QModelIndex()) override
virtual int rowCount(const QModelIndex &parent = QModelIndex()) const override
virtual void setSourceModel(QAbstractItemModel *newSourceModel) override
virtual QModelIndex sibling(int row, int column, const QModelIndex &idx) const override

保护函数

(since 6.8) void setHandleSourceDataChanges(bool b)
(since 6.8) void setHandleSourceLayoutChanges(bool b)

详细说明

QIdentityProxyModel 可用于准确转发源模型的结构，无需排序、过滤或其他转换。这在概念上类似于 A.I = A 的标识矩阵。

因为它不做排序或过滤，所以该类最适用于对源模型的data() 进行转换的代理模型。例如，可以创建一个代理模型来定义所使用的字体、背景颜色或工具提示等。这样就不需要在创建模型结构的同一个类中实现所有数据处理，还可以用来创建可重复使用的组件。

在第三方提供的源模型无法修改的情况下，这也提供了一种更改数据的方法。

class DateFormatProxyModel : public QIdentityProxyModel
{
  // ...

  void setDateFormatString(const QString &formatString)
  {
    m_formatString = formatString;
  }

  QVariant data(const QModelIndex &index, int role) const override
  {
    if (role != Qt::DisplayRole)
      return QIdentityProxyModel::data(index, role);

    const QModelIndex sourceIndex = mapToSource(index);
    const QDateTime dateTime = sourceModel()->data(sourceIndex, SourceClass::DateRole).toDateTime();
    return dateTime.toString(m_formatString);
  }

  QMap<int, QVariant> itemData(const QModelIndex &proxyIndex) const override
  {
      QMap<int, QVariant> map = QIdentityProxyModel::itemData(proxyIndex);
      map[Qt::DisplayRole] = data(proxyIndex);
      return map;
  }

private:
  QString m_formatString;
};

另请参阅 QAbstractProxyModel 、模型/视图编程和QAbstractItemModel 。

成员函数文档

[explicit] QIdentityProxyModel::QIdentityProxyModel(QObject *parent = nullptr)

用给定的parent 构建身份模型。

[virtual noexcept] QIdentityProxyModel::~QIdentityProxyModel()

摧毁这种身份模式。

[override virtual] int QIdentityProxyModel::columnCount(const QModelIndex &parent = QModelIndex()) const

重实现：QAbstractItemModel::columnCount(const QModelIndex &parent) const.

[override virtual] bool QIdentityProxyModel::dropMimeData(const QMimeData *data, Qt::DropAction action, int row, int column, const QModelIndex &parent)

重实现：QAbstractProxyModel::dropMimeData(const QMimeData *data, Qt::DropAction action, int row, int column, const QModelIndex &parent).

[since 6.8] bool QIdentityProxyModel::handleSourceDataChanges() const

如果此代理模型处理源模型数据更改，则返回true ，否则返回false 。

此函数在 Qt 6.8 中引入。

另请参阅 setHandleSourceDataChanges() 。

[since 6.8] bool QIdentityProxyModel::handleSourceLayoutChanges() const

如果此代理模型处理源模型布局更改，则返回true ，否则返回false 。

此函数在 Qt 6.8 中引入。

另请参阅 setHandleSourceLayoutChanges() 。

[override virtual] QVariant QIdentityProxyModel::headerData(int section, Qt::Orientation orientation, int role = Qt::DisplayRole) const

重实现：QAbstractProxyModel::headerData(int section, Qt::Orientation orientation, int role) const.

[override virtual] QModelIndex QIdentityProxyModel::index(int row, int column, const QModelIndex &parent = QModelIndex()) const

重实现：QAbstractItemModel::index(int row, int column, const QModelIndex &parent) const.

[override virtual] bool QIdentityProxyModel::insertColumns(int column, int count, const QModelIndex &parent = QModelIndex())

重实现：QAbstractItemModel::insertColumns(int column, int count, const QModelIndex &parent).

[override virtual] bool QIdentityProxyModel::insertRows(int row, int count, const QModelIndex &parent = QModelIndex())

重实现：QAbstractItemModel::insertRows(int row, int count, const QModelIndex &parent).

[override virtual] QModelIndex QIdentityProxyModel::mapFromSource(const QModelIndex &sourceIndex) const

重实现：QAbstractProxyModel::mapFromSource(const QModelIndex &sourceIndex) const.

[override virtual] QItemSelection QIdentityProxyModel::mapSelectionFromSource(const QItemSelection &selection) const

重实现：QAbstractProxyModel::mapSelectionFromSource(const QItemSelection &sourceSelection) const.

[override virtual] QItemSelection QIdentityProxyModel::mapSelectionToSource(const QItemSelection &selection) const

重实现：QAbstractProxyModel::mapSelectionToSource(const QItemSelection &proxySelection) const.

[override virtual] QModelIndex QIdentityProxyModel::mapToSource(const QModelIndex &proxyIndex) const

重实现：QAbstractProxyModel::mapToSource(const QModelIndex &proxyIndex) const.

[override virtual] QModelIndexList QIdentityProxyModel::match(const QModelIndex &start, int role, const QVariant &value, int hits = 1, Qt::MatchFlags flags = Qt::MatchFlags(Qt::MatchStartsWith|Qt::MatchWrap)) const

重实现：QAbstractItemModel::match(const QModelIndex &start, int role, const QVariant &value, int hits, Qt::MatchFlags flags) const.

[override virtual] bool QIdentityProxyModel::moveColumns(const QModelIndex &sourceParent, int sourceColumn, int count, const QModelIndex &destinationParent, int destinationChild)

重实现：QAbstractItemModel::moveColumns(const QModelIndex &sourceParent, int sourceColumn, int count, const QModelIndex &destinationParent, int destinationChild）。

[override virtual] bool QIdentityProxyModel::moveRows(const QModelIndex &sourceParent, int sourceRow, int count, const QModelIndex &destinationParent, int destinationChild)

重实现：QAbstractItemModel::moveRows(const QModelIndex &sourceParent, int sourceRow, int count, const QModelIndex &destinationParent, int destinationChild）。

[override virtual] QModelIndex QIdentityProxyModel::parent(const QModelIndex &child) const

重实现：QAbstractItemModel::parent(const QModelIndex &index) const.

[override virtual] bool QIdentityProxyModel::removeColumns(int column, int count, const QModelIndex &parent = QModelIndex())

重实现：QAbstractItemModel::removeColumns(int column, int count, const QModelIndex &parent).

[override virtual] bool QIdentityProxyModel::removeRows(int row, int count, const QModelIndex &parent = QModelIndex())

重实现：QAbstractItemModel::removeRows(int row, int count, const QModelIndex &parent).

[override virtual] int QIdentityProxyModel::rowCount(const QModelIndex &parent = QModelIndex()) const

重实现：QAbstractItemModel::rowCount(const QModelIndex &parent) const.

[protected, since 6.8] void QIdentityProxyModel::setHandleSourceDataChanges(bool b)

如果b 是true ，则此代理模型将处理源模型数据更改（通过连接QAbstractItemModel::dataChanged 信号）。

默认情况下，该代理模型将处理源模型数据的更改。

在QIdentityProxyModel 的子类中，如果需要特别处理源模型数据的变化，将其设置为false 可能会有用。

注意： 只有在调用setSourceModel() 后，调用此方法才会生效。

此函数在 Qt 6.8 中引入。

另请参阅 handleSourceDataChanges()。

[protected, since 6.8] void QIdentityProxyModel::setHandleSourceLayoutChanges(bool b)

如果b 是true ，则此代理模型将处理源模型布局变化（通过连接QAbstractItemModel::layoutAboutToBeChanged 和QAbstractItemModel::layoutChanged 信号）。

默认情况下，该代理模型将处理源模型的布局更改。

在QIdentityProxyModel 的子类中，如果需要特别处理源模型布局变化，将其设置为false 可能会有用。

注意： 只有在调用setSourceModel() 后，调用此方法才会生效。

此函数在 Qt 6.8 中引入。

另请参阅 handleSourceLayoutChanges()。

[override virtual] void QIdentityProxyModel::setSourceModel(QAbstractItemModel *newSourceModel)

重实现：QAbstractProxyModel::setSourceModel(QAbstractItemModel *sourceModel).

[override virtual] QModelIndex QIdentityProxyModel::sibling(int row, int column, const QModelIndex &idx) const

重实现：QAbstractProxyModel::sibling(int row, int column, const QModelIndex &idx) const.

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