c++ - 使用QModelIndex设置QTreeWidgetItem的背景

Question

我有一个带有qTreeWidget的MainWindow。要将元素添加到此小部件，我已经实现了以下功能:

QTreeWidgetItem *MainWindow::prepareIt(QTreeWidgetItem *it, const QString &name, const QString &descr)
{
    it->setText(0, name);
    it->setText(1, descr);
    return it;
}

QTreeWidgetItem *MainWindow::addRoot(const QString &name, const QString &descr)
{
    QTreeWidgetItem *it = prepareIt(new QTreeWidgetItem(ui->treeWidget), name, descr);
    it->setBackground( 0, QColor{112, 77, 75} );
    it->setBackground( 1, QColor{78, 90, 110} );
    return it;
}

QTreeWidgetItem *MainWindow::addChild(QTreeWidgetItem *parent, const QString &name, const QString &descr)
{
    auto child = new QTreeWidgetItem(parent);

    child->setBackground( 0, QColor{102, 67, 65} );
    child->setBackground( 1, QColor{68, 80, 99} );

    parent->addChild(prepareIt(child, name, descr));
    return child;
}


...
addRoot(...);
addChild(parent,...);
...

它按预期工作。现在，我要右键单击以突出显示此qTreeWidget中的某些条目。在MainWindow的C-Tor中，我实现了:

MainWindow::MainWindow(QWidget *parent)
    : QMainWindow(parent)
    , ui(new Ui::MainWindow)
{
    ...
    ui->treeWidget->setContextMenuPolicy(Qt::CustomContextMenu);
    connect(ui->treeWidget, SIGNAL (customContextMenuRequested(const QPoint &)), this, SLOT (rightClick(const QPoint &)));
    ...
}

插槽是

void MainWindow::rightClick(const QPoint &pt)
{
    QModelIndex idx = ui->treeWidget->indexAt(pt);
    if (idx.isValid())
    {
        qDebug() << idx.data().toString();
        qDebug() << idx << "index.row()" << idx.row() << " index.column()" << idx.column();
    }
}

该插槽按预期方式调用(qDebug可以正常工作)，但是如何从QModelIndex idx到相应的QTreeWidgetItem进行突出显示呢？还是有另一种方法来制作高亮/更改元素的颜色？

提前致谢!!

Answer 1

更改单元格的颜色:

一个可能的解决方案是使用setData()方法:

void MainWindow::rightClick(const QPoint &pt)
{
    QModelIndex idx = ui->treeWidget->indexAt(pt);
    if (idx.isValid())
    {
        ui->treeWidget->model()->setData(idx, QColor("red"), Qt::BackgroundRole);
    }
}

但这只会更改一个单元格，如果要更改颜色，则必须遍历整行:

更改行颜色:

void MainWindow::rightClick(const QPoint &pt)
{
    QModelIndex idx = ui->treeWidget->indexAt(pt);
    if (idx.isValid())
    {
        for(int c=0; c < ui->treeWidget->columnCount(); ++c){
            QModelIndex ix = idx.sibling(idx.row(), c);
            ui->treeWidget->model()->setData(ix, QColor("red"), Qt::BackgroundRole);
        }
    }
}

要么:

void MainWindow::rightClick(const QPoint &pt)
{
    QTreeWidgetItem *it = ui->treeWidget->itemAt(pt);
    if (it)
    {
        for(int c=0; c < ui->treeWidget->columnCount(); ++c){
            it->setBackground(c, QColor("red"));
        }
    }
}