跑马灯文字闪烁，及字体改变的问题。

[weixin_38051760]

#include <QtGui>#include "ticker.h"Ticker::Ticker(QWidget *parent)    : QWidget(parent){    offset = 0;    myTimerId = 0;}void Ticker::setText(const QString &newText){    myText = newText;    update();    updateGeometry();}QSize Ticker::sizeHint() const{    return fontMetrics().size(0, text());}void Ticker::paintEvent(QPaintEvent * /* event */){    QPainter painter(this);   // QFont font("Courier" , 24);  //  painter.setFont(font);    int textWidth = fontMetrics().width(text());    int textHeight =fontMetrics().height();    if (textHeight < 1)        return;    int x = -offset;   // while (x < width()) {    while(x<height()){       // painter.drawText(x, 0, textWidth, height(),      //                   Qt::AlignLeft | Qt::AlignVCenter, text());        painter.drawText(0,x,width(),height(),Qt::AlignLeft|Qt::AlignVCenter,text());       // x += textWidth;        x+=textHeight;    }}void Ticker::showEvent(QShowEvent * /* event */){    myTimerId = startTimer(10);}void Ticker::timerEvent(QTimerEvent *event){    if (event->timerId() == myTimerId) {        offset++;        if(offset>=fontMetrics().height())            offset=0;      //  if (offset >= fontMetrics().width(text()))       //     offset = 0;       // scroll(-1, 0);        scroll(0,-1);    } else {        QWidget::timerEvent(event);    }}void Ticker::hideEvent(QHideEvent * /* event */){    killTimer(myTimerId);    myTimerId = 0;}参考论坛的例子修改的上下滚动效果，但是发现字会闪烁，另外我设定字体后，绘制的字上下会叠在一块，那位大哥，帮忙看一下咋回事。

[weixin_38063369]

菜鸟,qt刚接触不久,不熟.那位大哥帮忙看看,或者说一下实现的思路.