General and Desktop

In general the use of 'own/this' function in the constructor is only 'not sure' in C++ only if you are using virtual. The class is always fully constructed regarding itself and parents (inheritenance) but not from of the point of view of a possible child which inherits of you, because this one is not created. Mainly you should never call a virtual from this constructor or at least make sur that you are on you level: this->Note::addWidget(...); Now for the philosphy part: constructing widget in the constructor of a widget is not really a problem, it's the role of the constructor to 'construct' object and to link them.

Thanks for the link. Finally I just dig into QODBCResult and change a little the behaviour. I modify QODBCResult::data(int) and QODBCResult::fetch(int) (also deleting fetchNext() and fetchPrevious(), since I won't need any forward only query). I add a QList<QVariant> buffer, where I store my rows when they are requested. It's almost the same behaviour as default (I cache the whole row, not only the needed columns as Qt). My app take up to 38-40 Mbs in memory for 22k rows / 55 columns of text and floats in cache. GUI seems as fluent as before with a good connection. I may post a suggestion on Jira later, asking for cached results. Because on a slow connection the GUI is just freezed all the time.

[quote author="mprakash" date="1321384645"]Unfortunately it does not :( i m on Mac by the way on 64bit[/quote] Sorry, I tested this on Win7 and ArchLinux (all x64) and all worked fine. Maybe someone have the answer, will wait.

http://stackoverflow.com/questions/3547185/scroll-qtextbrowser-to-the-top This helped me. Thank you to everyone who tried to help me. I appreciate it. @ QTextDocument *document = my_browser->document(); QTextCursor cursor(document); for(int i=0; i<line_number-1 ; i++) { cursor.movePosition(QTextCursor::Down); } cursor.movePosition(QTextCursor::EndOfLine, QTextCursor::KeepAnchor); my_browser->setTextCursor(cursor); mainLayout->addWidget(my_browser); setLayout(mainLayout); @

Did you ever find a solution to this? I need to customize QFileOpen dialog by adding some columns to the list view portion which is related to what you are doing.

Probably by fixing your SVG files? :) Seriously -- reading the Qt source doesn't give any valuable information about suppressing them?

Index-based access for a QList is O(1).

Hi, Thanks for the reply. Well, I'm using VS2010 and I've not included the GUI part. Now I've got some workable solution by deriving from the QObject which I need to test further. Yes, its correct that I can't use QWidget if not using GUI.

I don't know about Qt (I think no), but you always can use QProcess and the following command: @cat /proc/asound/cards@

Great - that is a huge help. (Where to report bugs was my next question). I'll take it there. Cheers, -bms

For the record, I did get this to work. What I did might be heretical or horrible. In a nutshell, I reimplemented editorEvent() and eventFilter() to deal with the mouse click position and set the proper model index for the table view delegate.

mainwindow.cpp @ scene=new QGraphicsScene(this); view=new QGraphicsView(this); view->setScene(scene); @ one application is there i created in seperate class which is derived from QDilog....i created one buton in main window.. when i click on that button that dialog will open it contains some file reading thing in that file some rectitem co-ordinates are there...while i was reading the file i want to up date the scene with those rect coordinates.... now tell me how to add rectitem to the scene in that dialog class....is it possible to update the scene in different class??

ya i will try that

If I get it right, the problem seems to be that the spinbox has the focus and not the slider. If that is the case, my first thoughts will be to either give back the focus to the slider after any change in the spinbox propagate the keypress event from the spin box to the slider (so implement a keyevent listener in the spinbox too and send the event to the slider). But in both cases, please note that any widget in the window will have to do the same, or your changes will be vanished from adding new widgets. So, if this is the problem, I suggest to implement the event listener in the main widget and propagate it to the slider. Someone could have better suggestions.

Hi, Well, as you said "how you implement your class" , this is excatly what I needed. As I'm new to C++ concepts & Qt, I'm not getting understanding it properly. I've captured that here "11533":http://developer.qt.nokia.com/forums/viewthread/11533/ "scanner" class is the 3rd party dll and it will be calling my COM dll. One basic doubt is like , is that the 3rd party class which I'm deriving will be qurering my COM dll for the fundtion signature, is that for this case its useful. Waiting for reply, Thanks,

Hi, I've removed that error by putting the QWidget class as lafirst tem in the derived class list. @ class CLASSA_EXPORT ClassA : public QWidget, public QAxBindable, public scanner { Q_OBJECT ..... }; @ Thanks,

Do you include? @#include "NeHeWidget.h"@

You can reimplement hoveEvents. Somethin like this: highlightItem.h @ #ifndef HIGHLIGHTITEM_H #define HIGHLIGHTITEM_H #include <QGraphicsRectItem> #include <QPen> class HighlightItem : public QGraphicsRectItem { public: explicit HighlightItem(QGraphicsRectItem *parent = 0); protected: void hoverEnterEvent(QGraphicsSceneHoverEvent *event); void hoverLeaveEvent(QGraphicsSceneHoverEvent *event); void paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget); private: QPen m_pen; }; #endif // HIGHLIGHTITEM_H @ highlightItem.cpp @ #include "highlightitem.h" #include <QPainter> HighlightItem::HighlightItem(QGraphicsRectItem *parent) : QGraphicsRectItem(parent) { setAcceptHoverEvents(true); } void HighlightItem::hoverEnterEvent(QGraphicsSceneHoverEvent *event) { m_pen.setColor(Qt::cyan); update(); } void HighlightItem::hoverLeaveEvent(QGraphicsSceneHoverEvent *event) { m_pen.setColor(Qt::black); update(); } void HighlightItem::paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget) { painter->setPen(m_pen); painter->drawRect(rect()); } @