手机多媒体开发的时候经常需要后台扫描音乐文件，本篇使用ｑｔ一些库实现简单的后台扫描的类，继承了Qthread
playlist.h

ifndef PLAYLIST_H

define PLAYLIST_H

include

include

include

include

include

include

include

include

include

include

include

include

include

include

include

include

class PlayList : public QThread
{
Q_OBJECT
public:
explicit PlayList(QObject *parent = 0);
~PlayList();

Q_PROPERTY(QJsonArray playlist READ playlist NOTIFY playlistChanged)QJsonArray playlist();Q_INVOKABLE void findMusic();Q_INVOKABLE int getItemsLength(){    return musicPath.count();}Q_INVOKABLE QString getMusicName(int id){    return musicPath.at(id).fileName();}Q_INVOKABLE QString getMusicPath(int id){    return musicPath.at(id).filePath();}void run();

signals:
void playlistChanged();

public slots:
private:
QList musicPath;

};

endif // PLAYLIST_H

playlist.cpp

include "playlist.h"

PlayList::PlayList(QObject *parent) : QThread(parent)
{

}

PlayList::~PlayList()
{

}
void PlayList::findMusic(){
this->start();
}

QJsonArray PlayList::playlist(){
QJsonArray jsarr;
QMutex mutex;
mutex.lock();
for(auto it:musicPath){
QJsonObject obj;
obj.insert("name",it.fileName());
obj.insert("path","file://"+it.filePath());
jsarr.append(obj);
}
mutex.unlock();
return jsarr;
}
void PlayList::run(){
QMutex mutex;
mutex.lock();
QString path="/mnt/sdcard";

//get all files's filtersQStringList filters;filters

效果图：

关键字：qt5, #c++#