QT改变QLineEdit的光标

效果

        

代码

头文件：

#ifndef QTLINEEDIT_H
#define QTLINEEDIT_H
#include <QLineEdit>
#include <QTimer>
#include <QPainter>
#include <QDebug>
#include <QProxyStyle>
#include <QCursor>
#include <QStyleHints>
#include <QApplication>
class CustomLineEditProxyStyle;

class QtLineEdit : public QLineEdit
{
    Q_OBJECT
public:
    explicit QtLineEdit(QWidget *parent = nullptr);
    ~QtLineEdit();

private slots:
    void sltUpdateCursorRect();
    void sltTextEdit(const QString &text);

private:
    CustomLineEditProxyStyle *m_proxyStyle;
    QTimer *m_timer;

protected:
    bool m_bShowCursor;
    void paintEvent(QPaintEvent *e) override;
};

#endif

CPP文件：

#include "QtLineEdit.h"

class CustomLineEditProxyStyle : public QProxyStyle
{
public:
    virtual int pixelMetric(PixelMetric metric, const QStyleOption* option = 0, const QWidget* widget = 0) const
    {
        if (metric == QStyle::PM_TextCursorWidth)
        {
            return 0;
        }
        return QProxyStyle::pixelMetric(metric, option, widget);
    }
};

QtLineEdit::QtLineEdit(QWidget *parent) : QLineEdit(parent)
{
    m_proxyStyle = new CustomLineEditProxyStyle();
    this->setStyle(m_proxyStyle);
    m_bShowCursor = false;
    m_timer = new QTimer(this);
    m_timer->setInterval(QGuiApplication::styleHints()->cursorFlashTime() / 2);
    connect(m_timer, SIGNAL(timeout()), this, SLOT(sltUpdateCursorRect()));
    m_timer->start();
    connect(this, SIGNAL(textEdited(QString)), this, SLOT(sltTextEdit(QString)));
}

QtLineEdit::~QtLineEdit()
{
    delete m_proxyStyle;
    m_proxyStyle = Q_NULLPTR;
}

void QtLineEdit::sltUpdateCursorRect()
{
    m_bShowCursor = !m_bShowCursor;
    QRect rect = cursorRect();
    rect.setX(rect.x() + 2);
    rect.setWidth(rect.width() + 5);
    this->update(rect);
}

void QtLineEdit::sltTextEdit(const QString &)
{
    m_bShowCursor = true;
}

void QtLineEdit::paintEvent(QPaintEvent *e)
{
    QLineEdit::paintEvent(e);
    if (this->hasFocus() && m_bShowCursor)
    {
        QPainter painter(this);
        QRect rect = this->cursorRect();
        rect.setX(rect.x() + 2);
        rect.setWidth(rect.width() + 5);
        painter.fillRect(QRect(rect.center().x(), rect.y(), 5, rect.height()), QColor(0, 0, 255));
    }
}