应用初始化本地数据，需要读取配置文件，小编介绍如何通过xml简单写入配置文件，至于为什么选择这个格式，主要因为在qml中有一个很好

的类使用：XmlListModel

xmlListModel能直接读取xml配置文件，快速方便开发，再加上自己写一个专门写入配置文件的类，两个就成了绝配啊！

代码：

datasbase.h

#ifndef DATASBASE_H

#define DATASBASE_H

#include

#include

#include

#include

#include

class DatasBase : public QObject

{

Q_OBJECT

public:

explicit DatasBase(QObject *parent = 0);

~DatasBase();

Q_INVOKABLE void setFileName(QString filename);

Q_INVOKABLE void writeStartDocument();

Q_INVOKABLE void writeStartElement(QString str);

Q_INVOKABLE void writeTextElement(QString elementT, QString content);

Q_INVOKABLE void writeEndElement();

Q_INVOKABLE void writeEndDocument();

Q_INVOKABLE bool openplaylistFile();

Q_INVOKABLE void closeplaylistFile();

signals:

public slots:

private:

QFile *playListDatas;

QDir *playListDatasdir;

QXmlStreamWriter *xmlWriter;

};

#endif // DATASBASE_H

datasbase.cpp

#include "datasbase.h"

#include

DatasBase::DatasBase(QObject *parent) : QObject(parent)

{

//"file:///mnt/android/data/colorlight/playlist->xml"

//配置文件的路径

playListDatasdir=new QDir("/mnt/sdcard/Android/data/colorlight/playlist.xml");

//判断是否存在文件

if(!playListDatasdir->exists()){

qDebug()<mkdir("/mnt/sdcard/Android/data/colorlight");

}

//初始化配置数据

playListDatas=new QFile("/mnt/sdcard/Android/data/colorlight/playlist.xml");

xmlWriter=new QXmlStreamWriter(playListDatas);

xmlWriter->setAutoFormatting(true);

qDebug()<absolutePath();

}

DatasBase::~DatasBase()

{

}

//设置配置文件的文件名

void DatasBase::setFileName(QString filename){

playListDatas->setFileName(filename);

}

bool DatasBase::openplaylistFile(){

return playListDatas->open(QIODevice::WriteOnly | QIODevice::Text);

}

void DatasBase::writeStartDocument(){

xmlWriter->writeStartDocument();

}

void DatasBase::writeStartElement(QString str){

xmlWriter->writeStartElement(str);

}

void DatasBase::writeTextElement(QString elementT, QString content){

xmlWriter->writeTextElement(elementT,content);

}

void DatasBase::writeEndElement(){

xmlWriter->writeEndElement();

}

void DatasBase::writeEndDocument(){

xmlWriter->writeEndDocument();

}

void DatasBase::closeplaylistFile(){

playListDatas->close();

}

通过这个类，我们可以方便在qml中调用写入数据配置的文件

下面是写入音乐列表配置的代码例子

XmlListModel{

id:playlistModel

source:"file:///mnt/sdcard/Android/data/colorlight/playlist.xml"

query: "/data/music"

XmlRole{

name:"name";query: "name/string()";isKey: true

}

XmlRole{

name:"path";query: "path/string()";isKey: true

}

onStatusChanged: {

if(status==XmlListModel.Ready){

for(var mindex=0;mindex

tempplaylistdata.append({"name":playlistModel.get(mindex).name,

"path":playlistModel.get(mindex).path})

}

}

}

}

ListModel{

id:tempplaylistdata

}

//保存扫描后的音乐文件

function saveDatas(){

if(tempplaylistdata.count==0){

return

}

// console.log()

datasbase.openplaylistFile()

datasbase.writeStartDocument()

datasbase.writeStartElement("data")

for(var a=0;a

datasbase.writeStartElement("music")

datasbase.writeTextElement("name",tempplaylistdata.get(a).name)

datasbase.writeTextElement("path",tempplaylistdata.get(a).path)

datasbase.writeEndElement()

}

datasbase.writeEndElement()

datasbase.writeEndDocument()

datasbase.closeplaylistFile()

}