花20亿做网站,做微信问卷调查的网站,浏览器观看的视频怎么下载,做特殊单页的网站很多时候#xff0c;我们需要在界面上画一些三角形、文字等之类的东西#xff0c;我们之需要重写paintEvent方法#xff0c;比如像这样
void Widget::paintEvent(QPaintEvent *event)
以下就是重写的代码。
void Widget::paintEvent(QPaintEvent *event)
{//创建QPainte…很多时候我们需要在界面上画一些三角形、文字等之类的东西我们之需要重写paintEvent方法比如像这样
void Widget::paintEvent(QPaintEvent *event)
以下就是重写的代码。
void Widget::paintEvent(QPaintEvent *event)
{//创建QPainter对象指明父对象否则不能看见QPainter painter(this);//先画一条线QPen pen;//设置线宽pen.setWidth(2);//设置颜色pen.setColor(Qt::red);//设置线的样式 实线、虚线pen.setStyle(Qt::DashDotLine);//设置线端点样式pen.setCapStyle(Qt::RoundCap);//设置画笔painter.setPen(pen);//画线painter.drawLine(10,10,100,100);//设置画刷QBrush brush;//画刷设置颜色brush.setColor(Qt::yellow);//设置填充样式brush.setStyle(Qt::SolidPattern);//设置画刷painter.setBrush(brush);//画四边形painter.drawRect(QRect(300,300,50,50));//画多边形三角形QPoint points[] {QPoint(200,200),QPoint(200,260),QPoint(260,260),};painter.drawPolygon(points,3);//设置字体QFont font;//字体大小font.setPointSize(30);//粗体font.setBold(true);//设置字体painter.setFont(font);//画字painter.drawText(400,400,QString(Qt));
}
运行如下图所示 更多QPainter相关的东西请看
Qt QPainter绘图_qt painter-CSDN博客
但是现在我们需要在播放视频的界面上绘制窗体像下面这样。
这里我叠加了一个Widget在上面widget上放了两个控件一个label和一个comboBox。 ui原型如下所示 首先我们需要定义一个叠加窗体类TopWidget
这个类很简单设置了窗体无边框和透明。 //窗口无边框setWindowFlags(Qt::FramelessWindowHint | Qt::Window);// 窗口透明this-setAttribute(Qt::WA_TranslucentBackground);
然后重写绘图事件。
#pragma once#include QWidget
#include QPaintEvent
#include QPainter
#include ui_TopWidget.hclass TopWidget : public QWidget
{Q_OBJECTpublic:TopWidget(QWidget *parent nullptr);~TopWidget();protected:void paintEvent(QPaintEvent *pEvent);private:Ui::TopWidgetClass ui;
};#include TopWidget.hTopWidget::TopWidget(QWidget *parent): QWidget(parent)
{ui.setupUi(this);//窗口无边框setWindowFlags(Qt::FramelessWindowHint | Qt::Window);// 窗口透明this-setAttribute(Qt::WA_TranslucentBackground);
}TopWidget::~TopWidget()
{}void TopWidget::paintEvent(QPaintEvent *pEvent)
{QStyleOption opt;opt.initFrom(this);QPainter p(this);style()-drawPrimitive(QStyle::PE_Widget, opt, p, this);//绘制样式
}在主界面中创建叠加窗体对象 TopWidget *m_widget nullptr; m_widget new TopWidget(this);m_widget-setStyleSheet(QString(background-color: rgba(255, 0, 0, 0%);));m_widget-show();
重写绘图和窗体移动事件我们需要在主窗体移动的时候叠加窗体跟随着主窗体移动。
void showWidget::paintEvent(QPaintEvent *event)
{QStyleOption opt;opt.initFrom(this);QPainter p(this);style()-drawPrimitive(QStyle::PE_Widget, opt, p, this);//绘制样式QPoint pos_form ui.widgetShow-mapToGlobal(ui.widgetShow-pos());m_widget-move(pos_form);m_widget-setGeometry(pos_form.x(), pos_form.y(), ui.widgetShow-width(), ui.widgetShow-height());
}void showWidget::moveEvent(QMoveEvent *event)
{QPoint pos_form ui.widgetShow-mapToGlobal(ui.widgetShow-pos());m_widget-move(pos_form);m_widget-setGeometry(pos_form.x(), pos_form.y(), ui.widgetShow-width(), ui.widgetShow-height());
}
完整源码
#pragma once
#define LIBVLC_USE_PTHREAD_CANCEL 1
#include QtWidgets/QWidget
#include ui_showWidget.h
#include QMenu
#include QActionGroup
#include vlc/vlc.h#include QDebug
#include QFileDialog
#include QThread
#include QMouseEvent
#include QKeyEvent
#include QPainter
#include TopWidget.henum Rate
{Rate2X,Rate1_5X,Rate1_25X,Rate1_0X,Rate0_75X,Rate0_5X
};class showWidget : public QWidget
{Q_OBJECTpublic:showWidget(QWidget *parent nullptr);~showWidget();protected:virtual void mouseDoubleClickEvent(QMouseEvent *event);virtual void keyPressEvent(QKeyEvent *event);virtual bool eventFilter(QObject *watched, QEvent *event);virtual void paintEvent(QPaintEvent *event);virtual void moveEvent(QMoveEvent *event);private slots:void slotOpenFile();void slotPlay();void slotPause();void slotStop();void slotValueChanged(int value);void slotCurrentIndexChanged(int index);void slotSnap();private://事件处理回调static void vlcEvents(const libvlc_event_t *ev, void *param);private:Ui::showWidgetClass ui;private:libvlc_instance_t *vlc_base nullptr;libvlc_media_t *vlc_media nullptr;libvlc_media_player_t *vlc_mediaPlayer nullptr;QListfloat m_lstRate;TopWidget *m_widget nullptr;
};#include showWidget.h
#include QTimer
#include QTime
#include QFileDialog#pragma execution_character_set(utf-8)showWidget::showWidget(QWidget *parent): QWidget(parent)
{ui.setupUi(this);m_widget new TopWidget(this);m_widget-setStyleSheet(QString(background-color: rgba(255, 0, 0, 0%);));m_widget-show();this-setWindowTitle(视频播放器);ui.cbxRate-setCurrentIndex(Rate1_0X);m_lstRate 2.0 1.5 1.25 1.0 0.75 0.5;vlc_base libvlc_new(0, NULL);ui.btnOpen-setFocusPolicy(Qt::NoFocus);ui.btnPlay-setFocusPolicy(Qt::NoFocus);ui.btnPause-setFocusPolicy(Qt::NoFocus);ui.btnStop-setFocusPolicy(Qt::NoFocus);ui.hSliderVolumn-setFocusPolicy(Qt::NoFocus);ui.cbxRate-setFocusPolicy(Qt::NoFocus);ui.horizontalSlider-installEventFilter(this);connect(ui.btnOpen, QPushButton::clicked, this, showWidget::slotOpenFile);connect(ui.btnPlay, QPushButton::clicked, this, showWidget::slotPlay);connect(ui.btnPause, QPushButton::clicked, this, showWidget::slotPause);connect(ui.btnStop, QPushButton::clicked, this, showWidget::slotStop);connect(ui.btnSnap, QPushButton::clicked, this, showWidget::slotSnap);connect(ui.hSliderVolumn, QSlider::valueChanged, this, showWidget::slotValueChanged);connect(ui.cbxRate,SIGNAL(currentIndexChanged(int)), this, SLOT(slotCurrentIndexChanged(int)));
}showWidget::~showWidget()
{libvlc_release(vlc_base); //减少libvlc实例的引用计数并销毁
}void showWidget::mouseDoubleClickEvent(QMouseEvent *event)
{if (this-isFullScreen()){this-showNormal();}else{this-showFullScreen();}
}void showWidget::keyPressEvent(QKeyEvent *event)
{if (!vlc_mediaPlayer)return;int value ui.hSliderVolumn-value();if (event-key() Qt::Key_W) //添加音量{qDebug() up;slotValueChanged(value10);}else if (event-key() Qt::Key_S) //减小音量{slotValueChanged(value - 10);}else if (event-key() Qt::Key_Space){if (vlc_mediaPlayer libvlc_media_player_get_state(vlc_mediaPlayer) libvlc_Playing){libvlc_media_player_pause(vlc_mediaPlayer);}else if (vlc_mediaPlayer libvlc_media_player_get_state(vlc_mediaPlayer) libvlc_Paused){libvlc_media_player_play(vlc_mediaPlayer);}}
}bool showWidget::eventFilter(QObject *watched, QEvent *event)
{if (watched ui.horizontalSlider) {if (event-type() QEvent::MouseButtonPress) {if (!vlc_mediaPlayer)return false;QMouseEvent *mouse static_castQMouseEvent*(event);libvlc_time_t totalLen libvlc_media_player_get_length(vlc_mediaPlayer);QPoint pos mouse-pos();libvlc_time_t time 0;time (double)pos.x() / ui.horizontalSlider-width() * totalLen;libvlc_media_player_set_time(vlc_mediaPlayer, time);return true;}else {return false;}}else {// pass the event on to the parent classreturn QWidget::eventFilter(watched, event);}
}void showWidget::paintEvent(QPaintEvent *event)
{QStyleOption opt;opt.initFrom(this);QPainter p(this);style()-drawPrimitive(QStyle::PE_Widget, opt, p, this);//绘制样式QPoint pos_form ui.widgetShow-mapToGlobal(ui.widgetShow-pos());m_widget-move(pos_form);m_widget-setGeometry(pos_form.x(), pos_form.y(), ui.widgetShow-width(), ui.widgetShow-height());
}void showWidget::moveEvent(QMoveEvent *event)
{QPoint pos_form ui.widgetShow-mapToGlobal(ui.widgetShow-pos());m_widget-move(pos_form);m_widget-setGeometry(pos_form.x(), pos_form.y(), ui.widgetShow-width(), ui.widgetShow-height());
}void showWidget::slotOpenFile()
{/*选择文件*/QString filename QFileDialog::getOpenFileName(this, 选择打开的文件, D:/, tr(*.*));std::replace(filename.begin(), filename.end(), QChar(/), QChar(\\));vlc_media libvlc_media_new_path(vlc_base, filename.toUtf8().data());if (!vlc_media) {return;}// 创建libvlc实例和媒体播放器vlc_mediaPlayer libvlc_media_player_new_from_media(vlc_media);if (!vlc_mediaPlayer) {return;}// 等待元数据加载完成libvlc_media_parse(vlc_media);libvlc_video_set_mouse_input(vlc_mediaPlayer, 0);libvlc_video_set_key_input(vlc_mediaPlayer, 0);// 获取各种元数据const char *title libvlc_media_get_meta(vlc_media, libvlc_meta_Title);const char *artist libvlc_media_get_meta(vlc_media, libvlc_meta_Artist);const char *album libvlc_media_get_meta(vlc_media, libvlc_meta_Album);const char *url libvlc_media_get_meta(vlc_media, libvlc_meta_URL);const char *date libvlc_media_get_meta(vlc_media, libvlc_meta_Date);const char *lang libvlc_media_get_meta(vlc_media, libvlc_meta_Language);int duration libvlc_media_get_duration(vlc_media); // 获取时长单位毫秒qDebug(Title: %s, title ? title : N/A);qDebug(Artist: %s, artist ? artist : N/A);qDebug(Album: %s, album ? album : N/A);qDebug(Duration: %d ms, duration);qDebug(url: %s, url ? url : N/A);qDebug(date: %s, date ? date : N/A);qDebug(lang: %s, lang ? lang : N/A);libvlc_media_track_t **tracks;int track_count libvlc_media_tracks_get(vlc_media,tracks);for (unsigned i 0; i track_count; i) {libvlc_media_track_t* track tracks[i];// 显示轨道信息printf(Track #%u: %s\n, i, track-psz_description);// 这里可以获取到每一个轨道的信息比如轨道类型 track-i_type// 可能是 libvlc_track_video, libvlc_track_audio 或者 libvlc_track_text (字幕)if (track-i_type libvlc_track_video) {// 处理视频轨道信息qDebug(width %d,track-video-i_width);qDebug(height %d, track-video-i_height);qDebug(rate_num %d, track-video-i_frame_rate_num);qDebug(rate_den %d, track-video-i_frame_rate_den);}else if (track-i_type libvlc_track_audio) {// 处理音频轨道信息qDebug(channels %d, track-audio-i_channels);qDebug(rate %d, track-audio-i_rate);}else if (track-i_type libvlc_track_text) {// 处理字幕轨道信息qDebug(psz_encoding %s, track-subtitle-psz_encoding);}}//获取事件管理器libvlc_event_manager_t *em libvlc_media_player_event_manager(vlc_mediaPlayer);// 注册事件监听器libvlc_event_attach(em, libvlc_MediaPlayerTimeChanged, vlcEvents, this);libvlc_event_attach(em, libvlc_MediaPlayerEndReached, vlcEvents, this);libvlc_event_attach(em, libvlc_MediaPlayerStopped, vlcEvents, this);libvlc_event_attach(em, libvlc_MediaPlayerPlaying, vlcEvents, this);libvlc_event_attach(em, libvlc_MediaPlayerPaused, vlcEvents, this);libvlc_media_player_set_hwnd(vlc_mediaPlayer, (void *)ui.widgetShow-winId());QTimer::singleShot(1000, this, showWidget::slotPlay);}void showWidget::slotPlay()
{if (vlc_mediaPlayer)libvlc_media_player_play(vlc_mediaPlayer);
}void showWidget::slotPause()
{if (vlc_mediaPlayer)libvlc_media_player_pause(vlc_mediaPlayer);
}void showWidget::slotStop()
{if (vlc_mediaPlayer)libvlc_media_player_stop(vlc_mediaPlayer);
}void showWidget::slotValueChanged(int value)
{if (vlc_mediaPlayer)libvlc_audio_set_volume(vlc_mediaPlayer, value);
}void showWidget::slotCurrentIndexChanged(int index)
{if (vlc_mediaPlayer)libvlc_media_player_set_rate(vlc_mediaPlayer, m_lstRate[index]);
}void showWidget::slotSnap()
{if (vlc_mediaPlayer){QString path ./snap.png;libvlc_video_take_snapshot(vlc_mediaPlayer, 0, path.toUtf8().data(), 0, 0);}
}//事件回调
void showWidget::vlcEvents(const libvlc_event_t *ev, void *param)
{showWidget *w (showWidget*)param;//处理不同的事件switch (ev-type) {case libvlc_MediaPlayerTimeChanged:{//qDebug() VLC媒体播放器时间已更改;qint64 len libvlc_media_player_get_time(w-vlc_mediaPlayer);libvlc_time_t lenSec len / 1000;libvlc_time_t totalLen libvlc_media_player_get_length(w-vlc_mediaPlayer);libvlc_time_t totalLenSec totalLen / 1000;int thh, tmm, tss;thh lenSec / 3600;tmm (lenSec % 3600) / 60;tss (lenSec % 60);QTime time(thh, tmm, tss);w-ui.lbCurTime-setText(time.toString(hh:mm:ss));thh totalLenSec / 3600;tmm (totalLenSec % 3600) / 60;tss (totalLenSec % 60);QTime TotalTime(thh, tmm, tss);w-ui.lbTotalTime-setText(TotalTime.toString(hh:mm:ss));double pos (double)lenSec / totalLenSec * 100;w-ui.horizontalSlider-setValue(pos);}break;case libvlc_MediaPlayerEndReached:qDebug() VLC播放完毕.;break;case libvlc_MediaPlayerStopped:qDebug() VLC停止播放;break;case libvlc_MediaPlayerPlaying:qDebug() VLC开始播放;break;case libvlc_MediaPlayerPaused:qDebug() VLC暂停播放;break;}
}
更多参考
QtFFmpegopengl从零制作视频播放器-1.项目介绍_qt opengl视频播放器-CSDN博客
libVLC 提取视频帧使用OpenGL渲染-CSDN博客
QT UDP通信单播、广播、组播-CSDN博客
QCharts -1.概述-CSDN博客
