Qt：在QTableView中使用各种自定义委托

QT的MVC（View/Delegate）模型十分强大，可以利用各种控件来对表格的输入进行限制，不过我以前一直没有过，这几天研究了一下，写个小例子，希望大家喜欢。

    如果看不懂这个例子，请先看QT的自带例子：http://qt-project.org/doc/qt-4.8/itemviews-spinboxdelegate.html

思路：

1：为每一列定义委托：
A：第一列是编号列，使用只读委托，令该列的单元格是只读的
B：第三列是ID列，只能输入1－12个数字，利用QLineEdit委托和正则表达式对输入进行限制
C：第四年龄列，利用QSpinBox委托进行输入限制，只能输入1－100之间的数字
D：第五列是性别列，利用QComboBox委托对输入进行限制，该列的单元格只能输入Male或Female
E：第六列是头像列，在该列的单元格中央放置一张头像

2：定义代理类，把所有单元格中的字符居中显示。

3：利用QSS，将表格的背景色弄成黄蓝相间。

截图：

上代码：

 #include

 //编号列，只读委托
 //这个方法我还真想不到，呵呵
 class ReadOnlyDelegate : public QItemDelegate
 {
     Q_OBJECT
 public:
     ReadOnlyDelegate(QObject *parent = 0): QItemDelegate(parent) { }
     QWidget *createEditor(QWidget*parent, const QStyleOptionViewItem &option,
         const QModelIndex &index) const
     {
         return NULL;
     }
 };

 //ID列，只能输入1－12个数字
 //利用QLineEdit委托和正则表达式对输入进行限制
 class UserIDDelegate : public QItemDelegate
 {
     Q_OBJECT
 public:
     UserIDDelegate(QObject *parent = 0): QItemDelegate(parent) { }
     QWidget *createEditor(QWidget *parent, const QStyleOptionViewItem &option,
         const QModelIndex &index) const
     {
         QLineEdit *editor = new QLineEdit(parent);
         QRegExp regExp("[0-9]{0,10}");
         editor->setValidator(new QRegExpValidator(regExp, parent));
         return editor;
     }
     void setEditorData(QWidget *editor, const QModelIndex &index) const
     {
         QString text = index.model()->data(index, Qt::EditRole).toString();
         QLineEdit *lineEdit = static_cast(editor);
         lineEdit->setText(text);
     }
     void setModelData(QWidget *editor, QAbstractItemModel *model,
         const QModelIndex &index) const
     {
         QLineEdit *lineEdit = static_cast(editor);
         QString text = lineEdit->text();
         model->setData(index, text, Qt::EditRole);
     }
     void updateEditorGeometry(QWidget *editor,
         const QStyleOptionViewItem &option, const QModelIndex &index) const
     {
         editor->setGeometry(option.rect);
     }
 };

 //年龄列，利用QSpinBox委托进行输入限制，只能输入1－100之间的数字
 class AgeDelegate : public QItemDelegate
 {
     Q_OBJECT
 public:
     AgeDelegate(QObject *parent = 0): QItemDelegate(parent) { }
     QWidget *createEditor(QWidget *parent, const QStyleOptionViewItem &option,
         const QModelIndex &index) const
     {
         QSpinBox *editor = new QSpinBox(parent);
         editor->setMinimum(1);
         editor->setMaximum(100);
         return editor;
     }
     void setEditorData(QWidget *editor, const QModelIndex &index) const
     {
         int value = index.model()->data(index, Qt::EditRole).toInt();
         QSpinBox *spinBox = static_cast(editor);
         spinBox->setValue(value);
     }
     void setModelData(QWidget *editor, QAbstractItemModel *model,
         const QModelIndex &index) const
     {
         QSpinBox *spinBox = static_cast(editor);
         spinBox->interpretText();
         int value = spinBox->value();
         model->setData(index, value, Qt::EditRole);
     }
     void updateEditorGeometry(QWidget *editor,
         const QStyleOptionViewItem &option, const QModelIndex &index) const
     {
         editor->setGeometry(option.rect);
     }
 };

 //性别列，利用QComboBox委托对输入进行限制
 //这一列的单元格只能输入Male或Female
 class SexDelegate : public QItemDelegate
 {
     Q_OBJECT
 public:
     SexDelegate(QObject *parent = 0): QItemDelegate(parent) { }
     QWidget *createEditor(QWidget *parent, const QStyleOptionViewItem &option,
         const QModelIndex &index) const
     {
         QComboBox *editor = new QComboBox(parent);
         editor->addItem("Female");
         editor->addItem("Male");
         return editor;
     }
     void setEditorData(QWidget *editor, const QModelIndex &index) const
     {
         QString text = index.model()->data(index, Qt::EditRole).toString();
         QComboBox *comboBox = static_cast(editor);
         int tindex = comboBox->findText(text);
         comboBox->setCurrentIndex(tindex);
     }
     void setModelData(QWidget *editor, QAbstractItemModel *model,
         const QModelIndex &index) const
     {
         QComboBox *comboBox = static_cast(editor);
         QString text = comboBox->currentText();
         model->setData(index, text, Qt::EditRole);
     }
     void updateEditorGeometry(QWidget *editor,
         const QStyleOptionViewItem &option, const QModelIndex &index) const
     {
         editor->setGeometry(option.rect);
     }
 };

 //头像列，只是在单元格中央放一张小图而已
 class IconDelegate : public QItemDelegate
 {
     Q_OBJECT
 public:
     IconDelegate(QObject *parent = 0): QItemDelegate(parent) { }
     void paint(QPainter *painter, const QStyleOptionViewItem &option,
         const QModelIndex & index ) const
     {
         //show.bmp是在工程目录中的一张图片（其实就是QQ的图标啦，呵呵）
         QPixmap pixmap = QPixmap("show.bmp").scaled(24, 24);
         qApp->style()->drawItemPixmap(painter, option.rect,  Qt::AlignCenter, QPixmap(pixmap));
     }
 };

 //代理类，把所有单元格中的字符居中显示
 class VIPModel : public QStandardItemModel
 {
     Q_OBJECT
 public:
     VIPModel(QObject *parent=NULL) : QStandardItemModel(parent) { }
     VIPModel(int row, int column, QObject *parent=NULL)
         : QStandardItemModel(row, column, parent) { }
     QVariant data(const QModelIndex &index, int role = Qt::DisplayRole) const
     {
         if( Qt::TextAlignmentRole == role )
             return Qt::AlignCenter;
         return QStandardItemModel::data(index, role);
     }

 };

 #include "main.moc"

 int main(int argc, char *argv[])
 {
     QApplication app(argc, argv);

     VIPModel *model = new VIPModel(5, 5);
     QTableView *tableView = new QTableView;

     //把表格的背景调成黄蓝相间
     //这种方法是在网上看到的，用起来还真方便啊
     tableView->setAlternatingRowColors(true);
     tableView->setStyleSheet("QTableView{background-color: rgb(250, 250, 115);"
         "alternate-background-color: rgb(141, 163, 215);}");

     tableView->setWindowTitle("VIP List");
     tableView->resize(700, 400);
     tableView->setModel(model);
     QStringList headerList;
     headerList << "No." << "ID" << "Name" << "Age" << "Sex" << "Show";
     model->setHorizontalHeaderLabels(headerList);
     tableView->verticalHeader()->setVisible(false);
     tableView->horizontalHeader()->setStretchLastSection(true);

     //为每一列加载委托
     ReadOnlyDelegate readOnlyDelegate;
     tableView->setItemDelegateForColumn(0, &readOnlyDelegate);
     UserIDDelegate userIDDelegate;
     tableView->setItemDelegateForColumn(1, &userIDDelegate);
     AgeDelegate spinBoxDelegate;
     tableView->setItemDelegateForColumn(3, &spinBoxDelegate);
     SexDelegate comboBoxDelegate;
     tableView->setItemDelegateForColumn(4, &comboBoxDelegate);
     IconDelegate iconDelegate;
     tableView->setItemDelegateForColumn(5, &iconDelegate);

     for(int i=0; i<10; i++)
     {
         QModelIndex index = model->index(i, 0, QModelIndex());
         model->setData(index, i);
     }

     tableView->show();
     return app.exec();
 }