QT跑马字幕

#include "qtextscroll.h" #include <QPainter> #include <QDebug> QTextScroll::QTextScroll(QWidget *parent): QLabel(parent) { stepTime = 20; stepWidth = 1; curIndex = 0; scrollTimer = new QTimer(); connect(scrollTimer, SIGNAL(timeout()), this, SLOT(updateIndex())); } void QTextScroll::showScrollText(QString text)//public接口，设置要滚动的文字，并开始滚动 { if(scrollTimer->isActive()) scrollTimer->stop(); showText = text; scrollTimer->start(stepTime); } void QTextScroll::updateIndex()//刷新滚动参数curIndex { update(); curIndex++; if (curIndex*stepWidth > width()) curIndex = 0; } void QTextScroll::paintEvent(QPaintEvent *event) { QWidget::paintEvent(event); QPainter painter(this); painter.drawText(0-stepWidth*curIndex, 100, showText);//画左半部分的文字 painter.drawText(width() - stepWidth*curIndex, 100, showText.left(curIndex));//画右半部分的文字 }