Question

How can i know that whether the scrollbar is displayed in a QPlainTextEdit ?
I tried QScrollBar::isHidden() , but always return true.

Appreciate any of your help !

Answer 1

You should try using the isVisible() method on your edit’s verticalScrollBar().

This works as expected here:

#include <QtGui>

class Win: public QWidget
{
    Q_OBJECT

    public:
        Win(QWidget *parent=0): QWidget(parent)
        {
            edit = new QPlainTextEdit;
            QPushButton *b1 = new QPushButton("click");
            QVBoxLayout *vl = new QVBoxLayout;
            vl->addWidget(edit);
            vl->addWidget(b1);
            setLayout(vl);
            connect(b1, SIGNAL(clicked()), this, SLOT(clicked()));
        }

    public slots:
        void clicked()
        {
            qDebug() << edit->verticalScrollBar()->isVisible();
        }

    private:
        QPlainTextEdit *edit;
};