Access to the user interface

[leon2225]

Hey,
I've got a problem. I use Qt since now a week and there's a problem wich I can't solve.
I have added a new class, Data, wich contains all data of me projekt. The Problem is that I want to write to the mainwindow, but I've a fail from the debugger ... :
Name of signal: SIGSEGV
Meaning: Segmentation fault

Here's the code, the fail apears inprintItsContent in data.cpp

Data.cpp:
@#include "data.h"

Data::Data(Fxhnn * pFxhnn) : MyFxhnn(pFxhnn),itsEncryptLevel(0), itsShuffleLevel(0)
{
itsKey = rand() % LONG_MAX;
}

...

void Data::printItsContent(){ // <---- here's the bug
MyFxhnn -> ui -> itsText->clear();
return;
}

...
...

//Daten Speichern und öffnen

bool Data::saveKeyAndMeta(){
QString fileName = QFileDialog::getSaveFileName(0, tr("Schlüssel Speichern"), QString(), tr("Fxhnn Key Files (*.FXHNNKEY)"));
if(!fileName.isEmpty()){
QFile file(fileName);
if(!file.open(QIODevice::WriteOnly)){
QMessageBox::critical(0, tr("Error"), tr("Could not save key"));
return false;
}
QDataStream stream(&file);
stream << itsKey << itsEncryptLevel << itsShuffleLevel;
file.close();
}
return true;
}

bool Data::saveContent(){
QString fileName = QFileDialog::getSaveFileName(0, tr("Text Speichern"), QString(), tr("Fxhnn Content Files (*.FXHNNCON)"));

if(!fileName.isEmpty()){
    QFile file(fileName);
    if(!file.open(QIODevice::WriteOnly)){
        QMessageBox::critical(0, tr("Error"), tr("Could not save file"));
        return false;
    }
    QTextStream stream(&file);
    stream << itsContent;
    stream.flush();
    file.close();
}
return true;

}

bool Data::saveAll(){
bool content = saveContent();
QMessageBox::critical(0, tr("No Error"), tr("Could save file"));
bool keyAndMeta = saveKeyAndMeta();

if(content && keyAndMeta)
    return true;

return false;

}

bool Data::openKeyAndMeta(){
QString fileName = QFileDialog::getSaveFileName(0, tr("Schlüssel Öffnen"), QString(),
tr("Fxhnn Key Files (*.FXHNNKEY)"));
if(!fileName.isEmpty()){
QFile file(fileName);
if(!file.open(QIODevice::WriteOnly)){
QMessageBox::critical(0, tr("Error"), tr("Could not open file"));
return false;
}
QDataStream in(&file);
in >> itsKey >> itsEncryptLevel >> itsShuffleLevel;
file.close();
}
return true;
}

bool Data::openContent(){
QString fileName = QFileDialog::getOpenFileName(0, tr("Inhalt öffnen"), QString(),
tr("Fxhnn Content Files (*.FXHNNCON)"));

if(!fileName.isEmpty()){
    QFile file(fileName);
    if(!file.open(QIODevice::ReadOnly)){
        QMessageBox::critical(0, tr("Error"), tr("Could not open file"));
        return false;
    }
    QTextStream in(&file);
    setItsContent(in.readAll());
    printItsContent();
    file.close();

    if(itsContent != MyFxhnn -> ui -> itsText -> toPlainText()){
        QMessageBox::critical(0, tr("Error"), tr("Fehler beim Öffnen, Data != Textfeld"));
        return false;
    }


}
return true;

}

bool Data::openAll(){
bool content = openContent();
bool keyAndMeta = openKeyAndMeta();

if(content && keyAndMeta)
    return true;

return false;

}
@

data.h:
@#ifndef DATA_H
#define DATA_H

#include <QWidget>
#include "fxhnn.h"
#include "ui_fxhnn.h"
#include <cstdlib>
#include <limits.h>
#include <QString>
#include <QFileDialog>
#include <QFile>
#include <QMessageBox>
#include <QTextStream>
#include <QDataStream>

class Fxhnn;

class Data : public QWidget
{
Q_OBJECT

Fxhnn *MyFxhnn;

public:
explicit Data(Fxhnn*);
~Data();

    //Zugriffe auf den Inhalt
QString getItsContent();
void printItsContent();
void setItsContent( QString newContent);
void readItsContent();

    //Zugriffe auf den Schlüssel
qint64 getItsKey();
void setItsKey( qint64 newKey);
void generateItsKey();

    //Zugriffe auf das Level der Verschlüsslung
void setItsEncryptLevel( short upDownGrade = 1);
ushort getItsEncryptLevel();
void setItsShuffleLevel( short upDownGrade = 1);
ushort getItsShuffleLevel();

    //Speichern der Daten
bool saveKeyAndMeta();
bool openKeyAndMeta();
bool saveContent();
bool openContent();
bool saveAll();
bool openAll();

signals:

public slots:
...

private:
qint64 itsKey;
QString itsContent;
ushort itsShuffleLevel;
ushort itsEncryptLevel;
};

#endif // DATA_H
@

fxhnn.cpp:
@
#include "fxhnn.h"
#include "ui_fxhnn.h"
#include "encrypttext.h"
#include "decrypttext.h"

Fxhnn::Fxhnn(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::Fxhnn)
{
ui->setupUi(this);

Data * MyData = new Data(this);
encryptText * encryptWidget = new encryptText(this);
decryptText * decryptWidget = new decryptText(this);

...

}

...
@

fxhnn.h:
@#ifndef FXHNN_H
#define FXHNN_H

#include <QMainWindow>
#include <cstdlib>
#include <limits.h>
#include <QFileDialog>
#include <QFile>
#include <QMessageBox>
#include <QTextStream>
#include <QDataStream>
#include "data.h"

namespace Ui {
class Fxhnn;
}

class Data;

class Fxhnn : public QMainWindow
{
Q_OBJECT

public:
explicit Fxhnn(QWidget *parent = 0);
~Fxhnn();

Ui::Fxhnn *ui;

Data *MyData;

private slots:
void changeMode();

void on_actionLoadContent_triggered();

void on_actionLoadKey_triggered();

void on_actionSaveContent_triggered();

void on_actionSaveKey_triggered();

void on_itsText_textChanged();

void on_actionAlles_Speichern_triggered();

void on_actionAlles_Laden_triggered();

private:

};

#endif // FXHNN_H
@

I hope that you could help me

Leon

PS: Sorry for the bit of german language ^^
PPS: I don't know wich files u need ..

[SGaist]

Hi,

in Fhxnn constructor you have:

@Data * MyData = new Data(this);@

which shadows your member variable of the same name. Thus I suspect that you call MyData->something later on and thus the crash.

[leon2225]

Okey ... how can I solve the problem ?
I can't delete @Data * MyData = new Data(this);@
But also not the declaration in fhxnn.h ..

[SGaist]

What about just:

@MyData = new Data(this);@

?

[leon2225]

Oh yes .. I've been a bit tired ^^

[leon2225]

But it still wont open the files ... there's no error or something like that, but the stream soen't write it's data into the member variables

[SGaist]

Are you sure you are reading the data correctly ?

[leon2225]

no ... I only meant that the compiler don't find a compile error, of course there have to be an error, if not it would work.
DO you have an idea where the error is? :D

[SGaist]

The debugger is your friend ;)

since you wrote it crashes here

@MyFxhnn -> ui -> itsText->clear();@

Are you sure everything is valid ?

[leon2225]

No that problem is fixed.
Also the debugger doesn't say anything, the only problem is, that the function openContent() doesn't write the data into itsContent ..

@bool Data::openContent(){
QString fileName = QFileDialog::getOpenFileName(MyFxhnn, tr("Inhalt öffnen"), QString(),
tr("Fxhnn Content Files (*.FXHNNCON)"));
QFile file(fileName);
if(!file.open(QIODevice::ReadOnly)){
QMessageBox::critical(MyFxhnn, tr("Error"), tr("Could not open file"));
return false;
}
QTextStream in(&file);
in >> itsContent;
printItsContent();
file.close();

    if(itsContent != MyFxhnn -> ui -> itsText -> toPlainText()){
        QMessageBox::critical(MyFxhnn, tr("Error"), tr("Fehler beim Öffnen, Data != Textfeld"));
        return false;
    }



return true;

}@

Leon

[SGaist]

From your code, I wouldn't expect openContent to write anything. You open the selected file in ReadOnly mode and you read from it after that.

[leon2225]

yea I meant that the function has to "write" the data from the stream into the variable ... but I don't know, where there should be the bug :/

[SGaist]

Ok, so you mean that "itsContent" doesn't receive the content of the file ?

Following your code printItsContent just clears the itsText widget content so when you compare the content of itsText to itsContent's value, your test will only succeed if itsContent is empty.

[leon2225]

I've changed that ... a few days ago :D
I'll post the new code .. :
data.h
@#ifndef DATA_H
#define DATA_H

#include <QWidget>
#include "fxhnn.h"
#include "ui_fxhnn.h"
#include <cstdlib>
#include <limits.h>
#include <QString>
#include <QFileDialog>
#include <QFile>
#include <QMessageBox>
#include <QTextStream>
#include <QDataStream>

class Fxhnn;

class Data : public QWidget
{
Q_OBJECT

Fxhnn *MyFxhnn;

public:
explicit Data(Fxhnn*);
~Data();

    //Zugriffe auf den Inhalt
QString getItsContent();
void printItsContent();
void setItsContent( QString newContent);
void readItsContent();
void reset();


    //Speichern der Daten
bool saveKeyAndMeta(bool customFileName = 0);
bool openKeyAndMeta(bool customFileName = 0);
bool saveContent(bool customFileName = 0);
bool openContent(bool customFileName = 0);
bool saveAll(bool customFileName = 0);
bool openAll(bool customFileName = 0);

signals:

private:
qint64 itsKey;
QString itsContent;
ushort itsShuffleLevel;
ushort itsEncryptLevel;
QString itsKeyFilename;
QString itsContentFilename;
};

#endif // DATA_H
@

data.cpp:
@#include "data.h"

Data::Data(Fxhnn * pFxhnn) : MyFxhnn(pFxhnn),itsEncryptLevel(0), itsShuffleLevel(0)
{
itsKey = rand() % LONG_MAX;
setItsEncryptLevel(0);
}

Data::~Data()
{

}

//Zugriffe auf itsContent

void Data::printItsContent(){
MyFxhnn -> ui -> itsText->clear();
MyFxhnn -> ui -> itsText -> setPlainText(itsContent);
setItsEncryptLevel(0);
setItsShuffleLevel(0);
return;
}

void Data::setItsContent(QString newContent){
itsContent = newContent;
return;
}

void Data::readItsContent(){
itsContent = MyFxhnn -> ui -> itsText -> toPlainText();
return;
}

//Zugriffe auf itsKey

qint64 Data::getItsKey(){
return itsKey;
}

void Data::setItsKey(qint64 newKey){
itsKey = newKey;
return;
}

void Data::generateItsKey(){
itsKey = rand() % USHRT_MAX;
return;
}

//Zugriffe auf das Level der Verschlüsslung
void Data::setItsEncryptLevel( short upDownGrade){
itsEncryptLevel = itsEncryptLevel + upDownGrade;

if(itsEncryptLevel <= 0){
    MyFxhnn -> ui -> itsIsEncrypted -> setText("Decrypted");
    MyFxhnn -> ui -> itsIsEncrypted -> setStyleSheet("QLabel {color : #CC0304; }");
}
else{
    if(itsEncryptLevel > 0){
        QString Out = "Encrypt Level ";
        Out.append(QString("%1").arg(itsEncryptLevel));
        MyFxhnn -> ui-> itsIsEncrypted-> setText(Out);
    }
    else
        MyFxhnn -> ui -> itsIsEncrypted -> setText("Encrypted");
    MyFxhnn -> ui -> itsIsEncrypted -> setStyleSheet("QLabel {color : #4ECC39; }");
}

}

ushort Data::getItsEncryptLevel(){
return itsEncryptLevel;
}

//Daten Speichern und öffnen

bool Data::saveKeyAndMeta(bool customFileName){
if(itsKeyFilename.isEmpty() || customFileName)
itsKeyFilename = QFileDialog::getSaveFileName(MyFxhnn, tr("Schlüssel Speichern"), QString(), tr("Fxhnn Key Files (*.FXHNNKEY)"));
if(!itsKeyFilename.isEmpty()){
QFile file(itsKeyFilename);
if(!file.open(QIODevice::WriteOnly)){
QMessageBox::critical(0, tr("Error"), tr("Could not save key"));
return false;
}
QDataStream stream(&file);
stream << itsKey << itsEncryptLevel << itsShuffleLevel;
file.close();
}
return true;
}

bool Data::saveContent(bool customFileName){
if(itsContentFilename.isEmpty() || customFileName)
itsContentFilename = QFileDialog::getSaveFileName(0, tr("Text Speichern"), QString(), tr("Fxhnn Content Files (*.txt)"));

if(!itsContentFilename.isEmpty()){
    QFile file(itsContentFilename);
    if(!file.open(QIODevice::WriteOnly)){
        QMessageBox::critical(0, tr("Error"), tr("Could not save file"));
        return false;
    }
    QTextStream stream(&file);
    stream << itsContent;
    file.close();
}
return true;

}

bool Data::saveAll(bool customFileName){
bool content = saveContent(customFileName);
bool keyAndMeta = saveKeyAndMeta(customFileName);

if(content && keyAndMeta)
    return true;

return false;

}

bool Data::openKeyAndMeta( bool customFileName){
if(itsKeyFilename.isEmpty() || customFileName )
itsKeyFilename = QFileDialog::getOpenFileName(0, tr("Schlüssel Öffnen"), QString(), tr("Fxhnn Key Files (*.FXHNNKEY)"));
if(!itsKeyFilename.isEmpty()){
QFile file(itsKeyFilename);
if(!file.open(QIODevice::ReadOnly)){
QMessageBox::critical(0, tr("Error"), tr("Could not open file"));
return false;
}
QDataStream in(&file);
in >> itsKey >> itsEncryptLevel >> itsShuffleLevel;
file.close();
printItsContent();
}
return true;
}

bool Data::openContent(bool customFileName){
if(itsContentFilename.isEmpty() || customFileName)
itsContentFilename= QFileDialog::getOpenFileName(MyFxhnn, tr("Inhalt öffnen"), QString(), tr("Fxhnn Content Files (*.txt)"));

if(!itsContentFilename.isEmpty()){
    QFile file(itsContentFilename);
    if(!file.open(QIODevice::ReadOnly)){
        QMessageBox::critical(MyFxhnn, tr("Error"), tr("Could not open file"));
        return false;
    }
    QTextStream in(&file);
    setItsContent(in.readAll());
    printItsContent();
    file.close();

    if((itsContent != MyFxhnn -> ui -> itsText -> toPlainText()) || itsContent == ""){
        QMessageBox::critical(MyFxhnn, tr("Error"), tr("Fehler beim Öffnen, Data != Textfeld"));
        return false;
    }
}


return true;

}

bool Data::openAll(bool customFileName){
bool content = openContent(customFileName);
bool keyAndMeta = openKeyAndMeta(customFileName);

if(content && keyAndMeta)
    return true;

return false;

}
@

[SGaist]

So is it working as you expect it to ?

[leon2225]

No it isn't ... it still have the problem that it couldn't read the data from the files.

[SGaist]

Rather than
@
QTextStream in(&file);
setItsContent(in.readAll());@

Why not just:
@
setItsContent(file.readAll());
@

In any case, are you sure that your file is not empty ?

[leon2225]

That doesn't work... And the file isn't empty

[SGaist]

Did you check what file.readAll() contains ?

since setItsContent only assign the parameter value to your itsContent member variable why not just do:

@itsContent = file.readAll()@

?

By the way, you should use const QString& in your setItsContent function, that will avoid unnecessary copies.

[leon2225]

Okey ehm file.readAll() return the right content of the file, the problem is, that it doesn't convert it into QString. readAll() gives back a QByteArray wich normaly could be converted in QString with for example:
@itsContent = QString(file.readAll());@

But it doesn't ...

here is the function again:
@bool Data::openContent(bool customFileName){
if(itsContentFilename.isEmpty() || customFileName)
itsContentFilename= QFileDialog::getOpenFileName(MyFxhnn, tr("Inhalt öffnen"), QString(), tr("Fxhnn Content Files (*.txt)"));

if(!itsContentFilename.isEmpty()){
    QFile file(itsContentFilename);
    if(!file.open(QIODevice::ReadOnly)){
        QMessageBox::critical(MyFxhnn, tr("Error"), tr("Could not open file"));
        return false;
    }
    QTextStream in(&file);
    QMessageBox::information(MyFxhnn, "Content of readAll(", file.readAll());
    itsContent = QString(file.readAll());
    QMessageBox::information(MyFxhnn, "Content of itsContent", QString(file.readAll()));
    printItsContent();
    file.close();

    if((itsContent != MyFxhnn -> ui -> itsText -> toPlainText()) || itsContent == ""){
        QMessageBox::critical(MyFxhnn, tr("Error"), tr("Fehler beim Öffnen, Data != Textfeld"));
        return false;
    }
}


return true;

}@

The Message "Content of readAll()" gives back the right content the other message return nothing an the last error message appears.