将 QItemDelegate 与 QAbstractTableModel 结合使用

Question

我有一个 QAbstractItemModel 和一个 QItemDelegate，这是我的问题。代表什么也不做。正在调用其子例程，但没有任何反应。

这是我希望在表中看到的内容。

Text : QComboBox : Text : Text : QProgressBar

其中 : 是列分隔符。

代表。 #ifndef DELEGATEACTION_H #define DELEGATEACTION_H

#include <QVariant>
#include <QItemDelegate>

#include <QWidget>
#include <QLabel>
#include <QComboBox>
#include <QProgressBar>

class DelegateAction : public QItemDelegate
{
    Q_OBJECT
public:
    explicit DelegateAction(QObject *parent = 0);

    QWidget* createEditor(QWidget *parent, const QStyleOptionViewItem &option, const QModelIndex &index) const;
    void setEditorData(QWidget *editor, const QModelIndex &index) const;
    void setModelData(QWidget *editor, QAbstractItemModel *model, const QModelIndex &index) const;
    void updateEditorGeometry(QWidget *editor, const QStyleOptionViewItem &option, const QModelIndex &index) const;
};

#endif // DELEGATEACTION_H

#include "DelegateAction.h"

DelegateAction::DelegateAction(QObject *parent) :
    QItemDelegate(parent)
{
}

QWidget * DelegateAction::createEditor(QWidget *parent, const QStyleOptionViewItem &option, const QModelIndex &index) const
{
    QWidget* editor = 0;

    switch (index.column())
    {
    case 0:
    default:
    {
        editor = new QLabel();
        break;
    }
    case 1:
    {
        QComboBox* combo = new QComboBox(parent);
        combo->addItem("Test");
        combo->addItem("Test 2");
        editor = combo;
        break;
    }
    case 4:
    {
        editor = new QProgressBar(parent);
        break;
    }
    }

    editor->installEventFilter(const_cast<DelegateAction*>(this));
    return editor;
}

void DelegateAction::setEditorData(QWidget *editor, const QModelIndex &index) const
{
    QVariant value = index.model()->data(index, Qt::DisplayRole);

    switch (index.column())
    {
    case 0:
    default:
    {
        QLabel* label = static_cast<QLabel*>(editor);
        label->setText(value.toString());
        break;
    }
    case 1:
    {
        QComboBox* combo = static_cast<QComboBox*>(editor);
        combo->setCurrentIndex(combo->findText(value.toString()));
        break;
    }
    case 4:
    {
        QProgressBar* progress = static_cast<QProgressBar*>(editor);
        progress->setValue(value.toInt());
        break;
    }
    }

}

void DelegateAction::setModelData(QWidget *editor, QAbstractItemModel *model, const QModelIndex &index) const
{
    QVariant value;
    switch (index.column())
    {
    case 0:
    default:
    {
        value = static_cast<QLabel*>(editor)->text();
        break;
    }
    case 1:
    {
        value = static_cast<QComboBox*>(editor)->currentText();
        break;
    }
    case 4:
    {
        value = static_cast<QProgressBar*>(editor)->value();
        break;
    }
    }

    model->setData(index, value);
}

void DelegateAction::updateEditorGeometry(QWidget *editor, const QStyleOptionViewItem &option, const QModelIndex &index) const
{
    editor->setGeometry(option.rect);
}

模型。

#ifndef MODELACTIONS_H
#define MODELACTIONS_H

#include <QAbstractTableModel>

#include <Unit.h>

class ModelAction : public QAbstractTableModel
{
    Q_OBJECT
public:
    explicit ModelAction(QObject *parent = 0);
    int rowCount(const QModelIndex &parent = QModelIndex()) const;
    int columnCount(const QModelIndex &parent = QModelIndex()) const;
    QVariant data(const QModelIndex &index, int role = Qt::DisplayRole) const;
    Qt::ItemFlags flags(const QModelIndex &index) const;
    QVariant headerData(int section, Qt::Orientation orientation, int role) const;
    bool setData(const QModelIndex &index, const QVariant &value, int role);
    void sort(int column, Qt::SortOrder order);


    void setUnits(const QList<Unit*>* units);

private:
    const QList<Unit*>* units;
    bool ascending[5];

};

#endif // MODELACTIONS_H

#include "ModelAction.h"

ModelAction::ModelAction(QObject *parent) :
    QAbstractTableModel(parent),
    units(0)
{
}

int ModelAction::rowCount(const QModelIndex &parent) const
{
    if (units == 0)
    {
        return 0;
    }
    else
    {
        return units->length();
    }
}
int ModelAction::columnCount(const QModelIndex &parent) const
{
    return 5;
}
QVariant ModelAction::data(const QModelIndex &index, int role) const
{
    if (index.isValid() == false)
    {
        return QVariant();
    }

    if (role == Qt::TextAlignmentRole)
    {
        if (index.column() == 0 || index.column() == 2)
        {
            return int(Qt::AlignLeft | Qt::AlignVCenter);
        }
        else
        {
            return int(Qt::AlignRight | Qt::AlignVCenter);
        }
    }
    else if (role == Qt::DisplayRole)
    {
        if (index.column() == 0)
        {
            // Unit's id.
            return index.row() + 1;
        }
        else if (index.column() == 1)
        {
            return "bob";
            // Unit's Action.
            //return mechs.at(index.row())->getWeight();
        }
        else if (index.column() == 2)
        {
            // Unit's Action start.
            //return mechs.at(index.row())->getTechnology();
        }
        else if (index.column() == 3)
        {
            // Unit's Action end.
            //return Currency::numberToCurrency(mechs.at(index.row())->getPurchaseValue());
        }
        else if (index.column() == 4)
        {
            // Unit's Action progress.
            //return Currency::numberToCurrency(mechs.at(index.row())->getSellValue());
        }
    }
    return QVariant();
}

QVariant ModelAction::headerData(int section, Qt::Orientation orientation, int role) const
{
    if (role != Qt::DisplayRole)
    {
        return QVariant();
    }

    if (orientation == Qt::Horizontal)
    {
        if (section == 0)
        {
            return "Id";
        }
        else if (section == 1)
        {
            return "Action";
        }
        else if (section == 2)
        {
            return "Begin Time";
        }
        else if (section == 3)
        {
            return "End Time";
        }
        else if (section == 4)
        {
            return "Progress";
        }
    }
    return QVariant();
}

void ModelAction::sort(int column, Qt::SortOrder order)
{
//    MechCompare compare;
//    compare.column = column;
//    ascending[column] = !ascending[column];
//    compare.ascending = ascending[column];
//    qSort(mechs.begin(), mechs.end(), compare);
    //    reset();
}

void ModelAction::setUnits(const QList<Unit *> *units)
{
    this->units = units;
    reset();
}

Qt::ItemFlags ModelAction::flags(const QModelIndex &index) const
{
    switch (index.column())
    {
    case 0:
    default:
    {
        return Qt::NoItemFlags;
        break;
    }
    case 1:
    {
        return Qt::ItemIsEditable | Qt::ItemIsEnabled;
    }
    }
}

bool ModelAction::setData(const QModelIndex &index, const QVariant &value, int role)
{
    switch (index.column())
    {
    case 1:
    {

    }
    }
}

我知道的唯一问题是 ModelAction::setData() 函数不完整。在完成该子例程之前，我必须返回并编辑该模型显示的数据类。组合框和进度条仍然应该显示，只是不执行任何操作。

此时，我只能看到表中每一行的 ID 号和测试文本“bob”。 QComboBox 和 QProgressBar 根本不渲染。

任何帮助将不胜感激。

杰克

Answer 1

您实现的委托函数适用于编辑。当您不编辑项目时，它们不会显示。看来您可能需要 QAbstractItemView::setIndexWidget 而不是委托。

Answer 2

createEditor 方法仅在某些事件发生后调用。例如，当您双击一个单元格时，...正如巴克指出的那样，您必须使用 setIndexWidget。