Some questions in Qt's Source Code

[jpn]

1. An explicit constructor makes sure no such statement (implicit conversion) is accepted:

QWidget widget = new QWidget;

QWidget widget = new QWidget;

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Otherwise compiler would accept the above statement because QWidget has a constructor that takes QWidget* (parent).

2. Take a look at QPointer docs. QPointer is a helper class that provides a guarded pointer.

3. See our wiki: Private implementation.

4. Many macros in Qt are just markers for meta-object compiler. That's why many of them are defined as empty.

[DeepDiver]

Again too fast for me! ;-)

[vql]

See our wiki: Private implementation.

Please give me your suggestion about programming technical like as easily maintainance.
Example: Qt is written in which pattern?

At the moment, I need to write some custom widgets for my application, example writting a widget like QDockWidget but it has a button to set AutoHide (similar in VS2005). Please give me some guidelines how to design it? Do you have some source codes for custom widgets? Thanks

[jpn]

Again too fast for me! ;-)

Sowwy!

Please give me your suggestion about programming technical like as easily maintainance.
Example: Qt is written in which pattern?

Sorry, what do you mean? I'm sure there is a bunch of various design patterns being used here and there in Qt.

Private implementation is rather a programming idiom. Pimpl is used all over Qt mainly because it gives the possibility to maintain binary backwards compatibility. As a negative side effect, pimpl causes tiny runtime overhead and increases complexity. You shouldn't use it because you find it cool. You should use it only if you find it somehow useful.

Do you have some source codes for custom widgets?

• wwWidgets
• Qxt

[vql]

http://www.wysota.eu.org/wwwidgets/

This link is die. What happen??? Thanks.