QTextEdit控件使用

QTextEdit控件使用

QTextEdit *mpContentTextEdit = new QTextEdit(this);

//设置占位符文本

mpContentTextEdit->setPlaceholderText(tr("Placeholder text"));

//设置关联控件，用于QTextEdit控件捕获MouseButtonPress等事件

QWidget *mpContentWidget = mpContentTextEdit->viewport();

//设置事件过滤器

mpContentTextEdit->installEventFilter(this);

mpContentWidget->installEventFilter(this);

//QTextEdit处理占位符及事件

bool eventFilter(QObject *obj, QEvent *pEvent)

{

    if (obj == mpContentTextEdit)

    {

        if (pEvent->type() == QEvent::FocusIn)

        {

            //清空编辑框默认占位符

            mpContentTextEdit->setPlaceholderText("");

        }

        else if (pEvent->type() == QEvent::FocusOut)

        {

            //设置编辑框默认占位符

            mpContentTextEdit->setPlaceholderText(tr("Placeholder text"));

        }

    }

    if ((((QKeyEvent *)pEvent)->key() == Qt::Key_Tab || pEvent->type() == QEvent::MouseButtonPress)

        && mpContentWidget->hasFocus())

    {

        //通过关联控件，可间接拦截编辑框鼠标等事件操作

        mpContentTextEdit->setText("");

    }

    return QDialog::eventFilter(obj, pEvent);

}