如何使用融合样式禁用焦点边框和背景 QTreeWidget？

Question

如何使用融合样式禁用焦点边框和背景 QTreeWidget？焦点很烦人。特别是当我使用交替的原始颜色时。

#include <QApplication>
#include <QWidget>
#include <QTreeWidget>
#include <QMessageBox>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    a.setStyle("fusion");

    QWidget *mainWidget = new QWidget();
    mainWidget->resize(200,150);

    QTreeWidget *myTree = new QTreeWidget(mainWidget);
    myTree->resize(200,150);

    QTreeWidgetItem *item;
    item = new QTreeWidgetItem(myTree);
    item->setText(0,"item1");
    //...
    item = new QTreeWidgetItem(myTree);
    item->setText(0,"item6");

    myTree->setAlternatingRowColors(true);
    myTree->setStyleSheet("QTreeView {background-color: #222222;"
                          "           alternate-background-color: #333333;"
                          "           selection-background-color: #FF77FF;}");

    myTree->setFocus();
    item->setSelected(true);

    mainWidget->show();
    return a.exec();
}

Answer 1

我花了一些时间才弄清楚这一点，但我也对 Qt 样式表有所了解。基本上有必要设置QTreeView::item 的CSS 属性，以防伪状态selected 被禁用而伪状态focus 被启用。

如果想要禁用小焦点矩形的绘制，可以使用自定义的QProxyStyle 来执行此操作，如 (https://stackoverflow.com/a/17294081/5762796) 所示。

看起来，焦点框的样式没有 Qt Css 属性。

#include <QApplication>
#include <QWidget>
#include <QTreeWidget>
#include <QProxyStyle>

// Disables focus drawing for all widgets
class Style_tweaks : public QProxyStyle
{
public:
    void drawPrimitive(PrimitiveElement element, const QStyleOption *option,
        QPainter *painter, const QWidget *widget) const
    {
        if (element == QStyle::PE_FrameFocusRect) return;

        QProxyStyle::drawPrimitive(element, option, painter, widget);
    }
};


int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    a.setStyle("fusion");
    a.setStyle(new Style_tweaks);

    auto myTree = new QTreeWidget;
    myTree->resize(200, 150);

    auto item1 = new QTreeWidgetItem(myTree);
    item1->setText(0, "item1");
    auto item2 = new QTreeWidgetItem(myTree);
    item2->setText(0, "item6");
    auto item3 = new QTreeWidgetItem(myTree);
    item3->setText(0, "item7");

    myTree->setAlternatingRowColors(true);
    myTree->setStyleSheet("\
        QTreeView {background-color: #222222; alternate-background-color: #333333; selection-background-color: #FF77FF; } \
        QTreeView::item:!selected:focus { background-color: #222222; alternate-background-color: #333333; selection-background-color: #222222;outline-color: white}\
    ");

/*  item3->setSelected(true);*/
    myTree->setFocus();
    item3->setSelected(true);

    myTree->show();
    return a.exec();
}