Widget GPS

[toro.86]

Hi, I would like to add to my Qt creator Application

http://casolaredercole.it/mobile/crono2.zip

the GPS widget like in this image

http://www.casolaredercole.it/mobile/displaydd.jpg

Help me please

[wysota]

And what is keeping you from doing that?

[toro.86]

i don't know how to start/beginner

[marcvanriet]

See "creating custom widgets" starting on page 5 of "C++ GUI programming with Qt4, second edition". I'm sure you can get it somewhere. Or do some google searches on "qt custom widget".

Creating a custom widget is not so difficult, but is not something we can/will just tell you in this thread.

One advice : don't start to try to integrate your widget in Qt Designer. That is quite more complex. If it's just for a single application, you can just promote a widget on your form to the new class you create.

Best regards,
Marc

[wysota]

See "creating custom widgets" starting on page 5 of "C++ GUI programming with Qt4, second edition". I'm sure you can get it somewhere. Or do some google searches on "qt custom widget".

I would rather start with the Analog clock widget example.

[MTK358]

I don't understand exactly what you mean. Do you mean the 5 bar thing in the top-left corner?

If so, just create a custom widget derived from QWidget, add signals and slots called setValue(int) and value(int) or something like that to set the number of bars shown, and reimplement the paint() method to draw the bars based on the value.

See the documentation for the QWidget::paintEvent() method and the QPainter class.

[toro.86]

I'm sorry but I have need of the code because I do not know in order to write it... i'm incapable

[MTK358]

You should learn the basics of C++ and Qt (specifically, how to use signals and slots) first, then. Once you know that, it should be quite simple.

[toro.86]

I have 1 day of time in order to make it help me please

[MTK358]

I have 1 day of time in order to make it help me please

OK. First, do you know how to define your own signals and slots?

http://doc.trolltech.com/4.6/signalsandslots.html

[toro.86]

for the time being a any signal goes well or generic slots.

is it possible to add this widget in this code?

http://casolaredercole.it/mobile/crono2.zip


http://www.casolaredercole.it/mobile/displaydd.jpg

[MTK358]

I don't understand.

[toro.86]

they are interested to graphically visualize 4 vertical lines with under written GPS like in this image
http://www.casolaredercole.it/mobile/displaydd.jpg ,

for the time being I do not know the sign that I will receive

[MTK358]

for the time being I do not know the sign that I will receive

What does that mean?

Anyway, I'm working on an example.

[toro.86]

What does that mean?

Anyway, I'm working on an example.

one moment max 5 minute I sent you one private message

[MTK358]

I didn't get any private message. Anyway, the code:

barwidget.h

#ifndef BARWIDGET_H
#define BARWIDGET_H
 
#include <QtGui>
 
class BarWidget : public QWidget
{
Q_OBJECT
public:
    explicit BarWidget(QWidget *parent = 0);
 
    int value();
 
protected:
    void paintEvent(QPaintEvent *);
 
signals:
    void valueChanged(int);
 
public slots:
    void setValue(int);
 
private:
    int currentValue;
};
 
#endif // BARWIDGET_H

#ifndef BARWIDGET_H
#define BARWIDGET_H

#include <QtGui>

class BarWidget : public QWidget
{
Q_OBJECT
public:
    explicit BarWidget(QWidget *parent = 0);

    int value();

protected:
    void paintEvent(QPaintEvent *);

signals:
    void valueChanged(int);

public slots:
    void setValue(int);

private:
    int currentValue;
};

#endif // BARWIDGET_H

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barwidget.cpp:

#include "barwidget.h"
 
BarWidget::BarWidget(QWidget *parent) :
    QWidget(parent)
{
    currentValue = 0;
}
 
int BarWidget::value()
{
    return currentValue;
}
 
void BarWidget::setValue(int newValue)
{
    if (newValue > 5)
        newValue = 5;
    else if (newValue < 0)
        newValue = 0;
    currentValue = newValue;
    emit valueChanged(newValue);
    repaint();
}
 
void BarWidget::paintEvent(QPaintEvent *)
{
    QPainter p(this);
    p.setPen(Qt::NoPen)
    p.setBrush(palette().text()); // draw the bars using the current theme's text color
 
    float barWidth = 0.15; // change this to the preferred width of the bars, as a fraction of the widget's width. Do not make it more than 0.20, or one fifth
    float gapWidth = (1.0 - (barWidth * 5)) / 4;
 
    switch (currentValue) // since there is no break after each case, it will fall through and draw the smaller bars
    {
    case 5:
        p.drawRect(QRectF( (barWidth+gapWidth)*4*width(), height()*(0/5.0), barWidth*width(), height() ));
    case 4:
        p.drawRect(QRectF( (barWidth+gapWidth)*3*width(), height()*(1/5.0), barWidth*width(), height() ));
    case 3:
        p.drawRect(QRectF( (barWidth+gapWidth)*2*width(), height()*(2/5.0), barWidth*width(), height() ));
    case 2:
        p.drawRect(QRectF( (barWidth+gapWidth)*1*width(), height()*(3/5.0), barWidth*width(), height() ));
    case 1:
        p.drawRect(QRectF( (barWidth+gapWidth)*0*width(), height()*(4/5.0), barWidth*width(), height() ));
    }
 
    p.end();
}

#include "barwidget.h"

BarWidget::BarWidget(QWidget *parent) :
    QWidget(parent)
{
    currentValue = 0;
}

int BarWidget::value()
{
    return currentValue;
}

void BarWidget::setValue(int newValue)
{
    if (newValue > 5)
        newValue = 5;
    else if (newValue < 0)
        newValue = 0;
    currentValue = newValue;
    emit valueChanged(newValue);
    repaint();
}

void BarWidget::paintEvent(QPaintEvent *)
{
    QPainter p(this);
    p.setPen(Qt::NoPen)
    p.setBrush(palette().text()); // draw the bars using the current theme's text color

    float barWidth = 0.15; // change this to the preferred width of the bars, as a fraction of the widget's width. Do not make it more than 0.20, or one fifth
    float gapWidth = (1.0 - (barWidth * 5)) / 4;

    switch (currentValue) // since there is no break after each case, it will fall through and draw the smaller bars
    {
    case 5:
        p.drawRect(QRectF( (barWidth+gapWidth)*4*width(), height()*(0/5.0), barWidth*width(), height() ));
    case 4:
        p.drawRect(QRectF( (barWidth+gapWidth)*3*width(), height()*(1/5.0), barWidth*width(), height() ));
    case 3:
        p.drawRect(QRectF( (barWidth+gapWidth)*2*width(), height()*(2/5.0), barWidth*width(), height() ));
    case 2:
        p.drawRect(QRectF( (barWidth+gapWidth)*1*width(), height()*(3/5.0), barWidth*width(), height() ));
    case 1:
        p.drawRect(QRectF( (barWidth+gapWidth)*0*width(), height()*(4/5.0), barWidth*width(), height() ));
    }

    p.end();
}

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[toro.86]

thanks i sent you a private message now

[MTK358]

I got your PM, and I didn't realize you want the whole thing! I thought you only wanted the bar part that said "GPS" under it!

[wysota]

I wouldn't do that for $100

On the other hand I'll give you (the original poster) a hint - prepare a set of graphics files for each subcomponent of your "widget" and only render them to the final canvas. That's what is often done in embedded world and I think that's what you are targetting too.

[MTK358]

Another question: do you want one widget with all the things or will it be OK to use separate existing widgets, like QLabel and QLCDNumber (which makes much more sense)?

BTW what is this for, if you don't mind sharing?