How to define static members in a static function in .cpp file?
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@jsulm okay.
ampconfiguration.h
static double sampling_rate; int getSampling_rate()const; void setSampling_rate(int value); static void ReadIni();ampconfiguration.cpp
void AmpConfiguration::ReadIni() { QFile fp("AmpConfiguration.txt"); if(!fp.open(QIODevice::ReadOnly) { QMessageBox::information::(nullptr,"file error","file not found",QMessageBox::Ok); } QStringList *line_list=new QStringList; QTextStream txt_stream(&fp); while(!txt_stream.atEnd()) { QString line=txt_stream.readLine(); QStringList temp=line.split("=",QString::SkipEmptyParts); line_list->push_back(temp.at(1)); } sampling_rate=line_list->at(0).toDouble(); } //I am getting error in the building itself not on the runtime. -
@thippu Please show your code (how you declare the static variable and how you're initialising it).
It sounds like you did not define the static member. You need this in your cpp:double AmpConfiguration::sampling_rate; -
@jsulm said in How to define static members in a static function in .cpp file?:
double AmpConfiguration::sampling_rate;
double AmpConfiguration::sampling_rate=10.2//like this? in the static function?@thippu said in How to define static members in a static function in .cpp file?:
in the static function?
No. Like this:
double AmpConfiguration::sampling_rate=10.2; void AmpConfiguration::ReadIni() -
@thippu Not really what I asked...
Did you adddouble AmpConfiguration::sampling_rate;to your cpp file?
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@jsulm yes bro, I did add like this
double AmpConfiguration::sampling_rate=line_list->at(0).toDouble();
but new error camequalified-id decalration before "=" token@thippu said in How to define static members in a static function in .cpp file?:
double AmpConfiguration::sampling_rate=line_list->at(0).toDouble();
Please read again what I wrote.
Where do you call this now?
It looks like you're now trying to declare a LOCAL variable with same name which is for sure not what you want to do. -
@thippu said in How to define static members in a static function in .cpp file?:
double AmpConfiguration::sampling_rate=line_list->at(0).toDouble();
Please read again what I wrote.
Where do you call this now?
It looks like you're now trying to declare a LOCAL variable with same name which is for sure not what you want to do. -
@jsulm said in How to define static members in a static function in .cpp file?:
Where do you call this now?
In the
mainwindow.cpp@thippu said in How to define static members in a static function in .cpp file?:
In the mainwindow.cpp
WHERE EXACTLY?
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@thippu said in How to define static members in a static function in .cpp file?:
In the mainwindow.cpp
WHERE EXACTLY?
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@jsulm
In the constructor of mainwindow.cpp
I'm callingAmpConfiguration::ReadIni();First statement itself@thippu Can you actually be more precise when answering questions?
Do you mean you put that line in the constructor or inside ReadIni()?
But as I said: you're declaring a local variable with same name.
It must be like this:AmpConfiguration::sampling_rate=line_list->at(0).toDouble();AmpConfiguration:: can be removed as well...
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@thippu Can you actually be more precise when answering questions?
Do you mean you put that line in the constructor or inside ReadIni()?
But as I said: you're declaring a local variable with same name.
It must be like this:AmpConfiguration::sampling_rate=line_list->at(0).toDouble();AmpConfiguration:: can be removed as well...
@jsulm said in How to define static members in a static function in .cpp file?:
local variable
I would like it to be a global static variable.
and I would like to use it(initialize) inside
AmpConfiguration::ReadIni()@jsulm said in How to define static members in a static function in .cpp file?:
AmpConfiguration::sampling_rate=line_list->at(0).toDouble();
finally, Calling the
AmpConfiguration::ReadIni()in constructor ofmainwindow.cpp. -
@thippu Can you actually be more precise when answering questions?
Do you mean you put that line in the constructor or inside ReadIni()?
But as I said: you're declaring a local variable with same name.
It must be like this:AmpConfiguration::sampling_rate=line_list->at(0).toDouble();AmpConfiguration:: can be removed as well...
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@jsulm said in How to define static members in a static function in .cpp file?:
AmpConfiguration::sampling_rate=line_list->at(0).toDouble();
No, change in the error. still, I'm getting undefined reference
@thippu "I would like it to be a global static variable." - then why do you declare it as local variable?
Did you putdouble AmpConfiguration::sampling_rate=10.2; // This has to be OUTSIDE of any method/constructor void AmpConfiguration::ReadIni() { sampling_rate=line_list->at(0).toDouble(); }as I already wrote above?
Please read about static members in C++. -
@thippu "I would like it to be a global static variable." - then why do you declare it as local variable?
Did you putdouble AmpConfiguration::sampling_rate=10.2; // This has to be OUTSIDE of any method/constructor void AmpConfiguration::ReadIni() { sampling_rate=line_list->at(0).toDouble(); }as I already wrote above?
Please read about static members in C++.
