How to create a SlotOfQImage in QT Rust? - qt

I'm trying to define a custom QT Slot/Signal for passing a QImage.
I'm using qt_widgets crate which has many predefined slot types like SlotOfQIcon. However it doesn't have one for QImage. I've looked at the source code which is generated with this tool: https://github.com/rust-qt/ritual.
Is it possible to do this in regular Rust project without running complex multistage build involving code generation?
List of implemented slots for reference:
https://docs.rs/qt_widgets/0.3.0/x86_64-pc-windows-msvc/qt_widgets/
I've tried to copy paste generated code for other widgets and modify it, but it doesn't look like a right approach. I don't want to regenerate the whole library just for this case. Are there any simpler options?

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Defining new language based on C++

I would like to add a new language (called 'kiwi') into the Brackets code editor which is based on C++. It uses the exact same rules but has additional keywords.
I've already done the part of adding the additional keywords with separate syntax highlighting directly on the clike.js file but i don't really like directly modifying the def for C++
Can someone explain to me how I can achieve this? I don't really understand the difference between using def() and CodeMirror.defineMIME(). If this new language will take cpp/hpp input files, how will the editor switch from C++ -> kiwi?
Thanks in advance
Patching your local copy of the code, as you've done, might be perfectly fine for your needs. (And if you run from a Git copy of the source, it's easy to pull down updates without losing your local diffs).
If you want to do it a "cleaner" way, you can write a Brackets extension to define the new language - this way the change is easily shareable with others, and updating Brackets is even easier.
The way you'd do this roughly follows the Defining a new language docs:
Write an extension to package up your code that will define the new language (below)
The CM mode "clike" is already loaded, so you don't need to worry about that
Call CodeMirror.defineMIME() to set up a clike configuration with the right list of keywords - using a new mimetype name of your choosing. (Looking at the def() code in clike.js, I don't think the extra stuff it does is especially relevant for Brackets).
Call LanguageManager.defineLanguage() to tell Brackets about your new language mode (and what file extensions map to it, etc.). You should be able to mostly copy how the C++ mode is defined here - except with your new MIME name instead.
You should read CodeMirror documentation to find out about writing your modes.
But in short you can define your own type of clike language, by using CodeMirror.defineMIME().
You also asked what's the difference between def() and CodeMirror.defineMIME(). If you look at the code you can see that def() function is calling CodeMirror.defineMIME() at the end, so I believe it is just a more readable way of defining the type.
Also it seems that it's impossible to define more than one language on the same extension type (not 100% sure).

Displaying vector files in QT using GDAL/OGR

I am writing an application to load vector maps/shape files using gdal/ogr and display them onto a gui designed using Qt. I am new to dealing with vector files, I am not able to decide how to render them on GUI. Few approaches that come to my mind are:
- To convert vector files to raster and display them as raster..
- To draw each shape in vector file one by one (i dont know how to do this, I dont even know whether it would be even possible this using GDAL/OGR, or how complex this would be because in my case vector files can be very complex)
The decision how to render vector files is very important for me, because after displaying vector files i need to support some advanced features like projection change, interactive selection, Geo-referencing etc.
Can any one who has worked on vector/gis stuff, tell me how this is usually done and what Qt widget is used for displaying such data.
Displaying vectors is a tricky task since it requires rendering of geometries.
I would consider Quantum GIS (QGIS). It's actually also based on QT but comes with a sophisticated rendering engine. A custom QGIS application can even be run standalone.
I solved the problem of drawing vector files by writing rendering functions for each type of shape files. Qt's QPainter was really handy for drawing shapes like Polygon, Multipolygon, Line, Multiline and then displaying the output as QImage.

lupdate - common single words in the ts file?

Im learning how to use QT's translate stuff for the first time for work.
They already have things working to some degree and its my job to clean
things up and get it working properly as well as using lupdate to keep
things in sync when they change etc. We are also using QML in which we
wrote a wrapper function for all our strings, so lupdate does not find
our function to add to the .ts XML file. The reason we use a wrapper is
for centralizing other functions at once place for all strings. We also
dont always use a string literal in our 'source' argument but a defined
property, such as:
property string buttonTxt: "ButtonText"
then: commonTRFunction(context, buttonTxt)
which of course lupdate does not find for both reasons.
Ive looked into updating the lupdate source very briefly
and Im not sure if its worth trying to hack it to find our function or
write our own parser to find the standard QT tags AND also our new ones?
Secondly, and related to the first part, Id like a way to make one
context section that contains all the common words we use in our app
such as 'Back', 'Save', 'Ok' etc etc without repeating it over and over
throughout the .ts file. lupdate seems to repeat things over and over
in multiple contexts which seems both inefficient and a waste of lines
in the ts file.
I haven't found any QT docs that really explain the differences between tr(), qsTr(), qsTranslate(), QT_TR_NOOP() and QT_TRANSLATE_NOOP(). I know you sometimes need a context and the source,
and other times just use the source without a context. We dont use
the disambigous arg. Most of our code is in QML and not C++.
Also we are running lupdate from the command line.
Does anyone have thoughts, suggestions or even a tool someone wrote
that can be used for what we have? I appreciate your help.

How to integrate matlab with QT

I want to call matlab from QT 4 (used for UI only in my project) where i can pass values and read values back from matlab. and also run the .m scripts and then get the results back from matlab.
QT is irrelevant here.
You basically want to use the Matlab Engine. You can call Matlab from compiled C++ (for example). You'll probably want to use engOpen to start the connection and then engEvalString to run scripts. You may also want to use engGetVariable, mxGetClassID and mxGetDimensions to access the results.
But definitely read the documentation and try it, then come back with more detailed questions.

generating GUI for C++ code

i need to generate a GUI for a ready code written with C++ the code is divided into some classes containing one that represent user interface to facilitate generating GUI without big modifications on my code
and i already designed the GUI window using QT Designer
now i want to link both logical part (my classes)and GUI part(QT Designer output class) ,how to add all classes to the GUI,how to handle signals coming from GUI and send the appropriate input to the logical part
GUI
get some words from user
get slider input as an int
add files from HDD (logical part need full paths)
out some text
NOTE:first time with QT
thanks in advance for any help
You might want to start with these simple tutorials
http://www.qttutorial.com/qt/hello-qt-your-first-application/
http://www.qttutorial.com/qt/hello-qt-your-first-qt-application-part-2/
I you need a really simple solution - call this in desired order:
QInputDialog::getText();
QInputDialog::getInt();
QFileDialog::getOpenFileName();
QMessageBox::information();
QtAssistant should give you much more details and examples.

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