Qt For Beginners - Part 5Ask The Experts

Jeff TranterBrian Quinn

Christopher ProbstIntegrated Computer SolutionsVisit us at http://www.ics.com

Video: http://bit.ly/28Yllql Copyright 2016, Integrated Computers Solutions, Inc.

This work may not be reproduced in whole or in part without the express written consent ofIntegrated Computer Solutions, Inc.

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In QML, I have a Text item with wrapMode: Text.Wrap but the text isn't wrapping. What am I doing wrong?

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import QtQuick 2.6

Rectangle {

width: 400

height: 300

Text {

anchors.centerIn: parent

font.pixelSize: 18

width: parent.width

wrapMode: Text.Wrap

text: "No live organism can continue for long to exist sanely under conditions of absolute reality; even larks and katydids are supposed, by some, to dream. Hill House, not sane, stood by itself against its hills, holding darkness within; it had stood so for eighty years and might stand for eighty more. Within, walls continued upright, bricks met neatly, floors were firm, and doors were sensibly shut; silence lay steadily against the wood and stone of Hill House, and whatever walked there, walked alone."

}

}

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Would it be possible to go into more detail with kit configuration for cross-platform development and remote deployment? Preferably with device configuration and deployment demonstration. To demonstrate the concept you could use any device, but I have a particular interest in a Raspberry Pi running Linux, and a Surface Pro running Windows 10.

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Still having difficulty connecting to PostgreSQL from Qt. Looked at forums, followed their recommendations and still get "Not Loaded".There's a Russian and a Spanish step-by-step guide, which I find awkward to follow properly. Is there something very similar in English? Video plus text would be great. I'm using Windows 7 x64 and MingW. I can connect directly using pgAdmin3, Valentina Studio, MS-Visual Studio, SQL Studio for PSQL, LibreOffice... Hope you can help. Thanks in advance.

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Should I use the QML Designer in Qt Creator? I heard it was not really ready for production use.

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I would like to develop a simple app to open up a URL to a website and then get information from the website that will populate some fields in my app. What is the easiest way to do this? are there any Qt Quick controls that can assist?

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Is it possible to place a button widget over top of an QOpenGLWidget to make a UX comparable to Google maps? The button widget would be like the stationary user account button in Google maps while the map would live in the QOpenGLWidget. Ideally the button would be transparent. This person http://stackoverflow.com/questions/16889319/put-transparent-qwidget-on-top-of-qmediaview-in-qt5-on-ubuntu did something similar by making the button a separate window that tracked the main window, but is hackish.

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What are some of the pros and cons of using Qt resources?

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Can you give me some guidance on whether to use qmake, qbs, or cmake as my build system?

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Can I use QML to create an editable TableView that uses SQLite as the backend datastore? If so, how do I do this? If not, is there another technique I can use to achieve an editable table with a database backend?

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WebEngine is not available for MINGW on Windows. Will WebEngine support for MINGW be available soon for 5.7 ?

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How do you handle QML textEdit that anchored to bottom of screen on iOS and Android devices?

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Someone told me that widgets are obsolete? Should I not be using them?

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How can I contribute to the Qt project?

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Are all Qt classes derived from QObject?

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Are there virtual slots? How about virtual signals?

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Qt promises binary compatibility between releases. What does that mean?

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What does the access level (public, private, protected) mean for slots?

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What is the recommended approach for fetching and displaying images on iOS using Apple's Photos framework and Qt Quick? Simply invoking the default image picker is not sufficient because the intention is to allow the user to select multiple images. On Android this is fairly straightforward: fetch a set of URLs in C++, and pass them in a model to a QML view whose delegate includes an Image. However, it does not appear to be possible to use URLs in this way on iOS unless the image is an asset in the project. Moreover, iOS image data (NSData *) cannot be fed directly into the constructor for QImage, for example, with the idea of wrapping the QImage in a sub-class of QQuickPaintedItem. So, what can we do? Thank you!

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What is the difference, if any, between Qt Quick and QML?

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What is a d-pointer?

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I suspect I have a memory leak. How can I track it down?

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Is there a way to make system() calls through Qt? For example, can I open the Windows notepad from within a Qt application?

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How can I know what Qt header files I need to include?

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What is the preferred rendering backend to use for Qt on embedded Linux?

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This Completes the Qt for Beginners Webinar series.

Thanks for attending!

Watch for more webinars coming up in the future.Consider taking a formal Qt training class from ICS.

Hope to see you at the Qt World Summit 2016!

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