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Proxy Models (Part 2) - Video

Introduction to Qt Widgets - Part 63

Jesper K. Pedersen

16 July 2025

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To watch this video on our website please or view it directly on YouTube

In the previous episode we discussed the foundation of proxy models; in this episode I'll show you two implementations of such proxy models.

Links:
* KDAB Migration Services: https://www.kdab.com/services/software-consulting/legacy-framework-migration/

Chapters:
00:00 Welcome
00:35 Short recap
01:05 Subclassing QIdentityProxyModel
02:21 AllUpperCaseProxyModel
04:40 Live coding: Changing background color depending on type of media
10:04 Why is the trick with custom roles, so important?
12:09 Sorting using QSortFilterProxyModel
12:47 Filtering using QSortFilterProxyModel
13:07 Subclasing QSortFilterProxyModel for sorting
14:01 Subclassing QSortFilterProxyModel for filtering
19:01 QAbstractProxyModel - links to QWAM
20:37 Advertise: Migrating from photon or MFC
20:52 The alternative to implementing QAbstractProxyModel
23:03 Signals + never give out someone else's indexes
24:47 Final words on proxy models

The example code showcased in this video is available here:
https://github.com/KDABLabs/kdabtv/tree/master/Programming-With-Qt-Widgets

All 'Introduction to Qt Widgets - Module 1' videos: https://www.youtube.com/playlist?list=PL6CJYn40gN6hgf7zCKF2Rv9Y0WoN8RVGf

All 'Introduction to Qt Widgets - Module 2' videos:
https://www.youtube.com/playlist?list=PL6CJYn40gN6j_c41CFMprvg9EiWz0WdSy

All 'Introduction to Qt Widgets - Module 3' videos:
https://www.youtube.com/playlist?list=PL6CJYn40gN6hWZO_viEf1rfjgk4E6SCKd

All 'Introduction to Qt Widgets - Module 4' videos:
https://www.youtube.com/playlist?list=PL6CJYn40gN6iXUNQMb2GkEjV_oK6Xid9-

All 'Introduction to Qt Widgets - Module 5' videos:
https://www.youtube.com/playlist?list=PL6CJYn40gN6h1tsLAETdrrFlsVMeYpiHI

All 'Introduction to Qt Widgets - Module 6' videos:
https://www.youtube.com/playlist?list=PL6CJYn40gN6jIsRYriqN70V83t_mdDZHT

All 'Introduction to Qt Widgets - Module 7' videos: https://www.youtube.com/playlist?list=PL6CJYn40gN6hHyqD9ZxUqpd14LoHvadN7

All 'Introduction to Qt Widgets - Module 8' videos: https://www.youtube.com/playlist?list=PL6CJYn40gN6iCb8g5NSfVqX0JRFzFnxak

All 'Introduction to Qt Widgets - Module 9' videos:
https://www.youtube.com/playlist?list=PL6CJYn40gN6hALniX7Fw_Ly29bg7pXBqC

Please note that non-English dubs for all KDAB videos are auto-generated. These translations have not been moderated by us and may contain inaccuracies. We appreciate your understanding and apologize for any confusion this may cause.

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JesperKjaerPedersen

Jesper K. Pedersen

HR Director / COO

Jesper K. Pedersen – COO/HR director at KDAB. Jesper has actively developed with Qt since 1998 and, despite his fancy title, still does so.

He has held almost 100 training classes in Qt since 2000. Today, his greatest claim to fame is the QML youtube series and more recently his youtube series called Qt Widgets and More.

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