QTreeView model/View

QTreeView顾名思义是树形结构，分级目录。直接上代码吧。

首先是Item的定义，item的定义有点像链表，记录父节点和子节点，功能大概就是获取子节点数，获取父节点，子节点，增加子节点，获取数据等。

class TreeItem

{

public:

    TreeItem(QList<QVariant> data,TreeItem *parentItem = 0);

    int childCount();

    int columnCount();

    void appendChild(TreeItem *childItem);

    QVariant data(int column);

    TreeItem *parentItem();

    TreeItem *childItem(int row);

    int row();

private:

    TreeItem *m_parentItem;

    QList<TreeItem *> m_childItem;

    QList<QVariant> m_valueData;

};

#include "treeitem.h"

TreeItem::TreeItem(QList<QVariant> data,TreeItem *parentItem)

{

    m_parentItem = parentItem;

    m_valueData = data;

}

int TreeItem::childCount()

{

    return m_childItem.count();

}

int TreeItem::columnCount()

{

    return m_valueData.count();

}

void TreeItem::appendChild(TreeItem *childItem)

{

    m_childItem.append(childItem);

}

QVariant TreeItem::data(int column)

{

    return m_valueData.value(column);

}

TreeItem * TreeItem::parentItem()

{

    return m_parentItem;

}

TreeItem *TreeItem::childItem(int row)

{

    return m_childItem.value(row);

}

int TreeItem::row()

{

    if(m_parentItem)

        return m_parentItem->m_childItem.indexOf(const_cast<TreeItem *>(this));

    return 0;

}

model继承QAbstractItemModel，

#include <QAbstractItemModel>

#include "treeitem.h"

class TreeModel : public QAbstractItemModel

{

public:

    TreeModel();

    int columnCount(const QModelIndex &parent) const;

    QVariant data(const QModelIndex &index, int role) const;

    QModelIndex index(int row, int column, const QModelIndex &parent) const;

    QModelIndex parent(const QModelIndex &child) const;

    int rowCount(const QModelIndex &parent) const;

    QVariant headerData(int section, Qt::Orientation orientation, int role) const;

    void initModel();

public:

    TreeItem *m_rootItem;

};

#include "treemodel.h"

#include <QDebug>

#include <QIcon>

TreeModel::TreeModel()

{

    QList<QVariant> rootdata;

    rootdata << "Title";

    m_rootItem = new TreeItem(rootdata);

}

int TreeModel::columnCount(const QModelIndex &parent) const

{

    if(parent.isValid())

    {

        return static_cast<TreeItem *>(parent.internalPointer())->columnCount();

    }

    return m_rootItem->columnCount();

}

QVariant TreeModel::data(const QModelIndex &index, int role) const

{

    if(!index.isValid())

        return QVariant();

    if(role == Qt::DecorationRole && index.column()==0)

    {

        return QIcon("1.png");

    }

    if(role != Qt::DisplayRole)

        return QVariant();

    TreeItem *item = static_cast<TreeItem *>(index.internalPointer());

    return item->data(index.column());

}

QModelIndex TreeModel::index(int row, int column, const QModelIndex &parent) const

{

    if(!hasIndex(row,column,parent))

        return QModelIndex();

    TreeItem *parentItem;

    if(!parent.isValid())

        parentItem = m_rootItem;

    else

        parentItem = static_cast<TreeItem *>(parent.internalPointer());

    TreeItem *childItem = parentItem->childItem(row);

    if(childItem)

        return createIndex(row,column,childItem);

    else

        return QModelIndex();

}

QModelIndex TreeModel::parent(const QModelIndex &child) const

{

    if(!child.isValid())

        return QModelIndex();

    TreeItem *childItem = static_cast<TreeItem *>(child.internalPointer());

    TreeItem *parentItem = childItem->parentItem();

    if(parentItem == m_rootItem)

        return QModelIndex();

    return createIndex(parentItem->row(),0,parentItem);

}

int TreeModel::rowCount(const QModelIndex &parent) const

{

    TreeItem *parentItem;

    if(!parent.isValid())

        parentItem = m_rootItem;

    else

        parentItem = static_cast<TreeItem *>(parent.internalPointer());

    return parentItem->childCount();

}

QVariant TreeModel::headerData(int section, Qt::Orientation orientation, int role) const

{

    if (orientation == Qt::Horizontal && role == Qt::DisplayRole)

        return m_rootItem->data(section);

    return QVariant();

}

void TreeModel::initModel()

{

    QStringList sList;

    sList << "1111" << "2222" << "3333" << "4444" << "5555";

    QStringList ssList;

    ssList << "AAAA" << "BBBB" << "CCCC" << "DDDD" << "EEEE";

    for(int i = 0; i < 5; i++)

    {

        QList<QVariant> data;

        data << sList.at(i);

        TreeItem *item = new TreeItem(data, m_rootItem);

        for(int j = 0; j < 5; j++)

        {

            QList<QVariant> data1;

            data1 << ssList.at(i);

            TreeItem *item1 = new TreeItem(data1, item);

            item->appendChild(item1);

        }

        m_rootItem->appendChild(item);

    }

}

QTreeView

view = new QTreeView(this);

    view->setFixedSize(640,480);

    TreeModel *model = new TreeModel;

    model->initModel();

    view->setModel(model);

    view->show();