QPainTextEdit add wave line - qt

I've working on a small SQL IDE App which is a neat tool for writing SQL procedure for Oracle & DB2. I'm using Qt 4 as the GUI base.
Still I want to add instant grammar check function for My SQL IDE, it will write a wave line under the SQL code with grammar error,just like the VS2010 and eclipse. But I really don't know how to deal with this function.
I've using the QPlainTextEdit for the document edit class.
I'd appreciate if you can give some tips and hints!
Thank you for your time!

Take a look at QSyntaxHighlighter. It consists of code example on how to use it. Also QPlainTextEdit has chapter Using QPlainTextEdit as an Editor. Another thing that may become useful for you is Syntax Highlighter Example

Related

How to make own text editor for math equation?

I'm using C# on Windows (but I can also use C++)
What I want to make is just an own text editor that I can write/edit mathematical equations/formulas.
Reason why I'm looking for this function is that the calculations of my structural analyzing programs are only editable with in my C# code. I want my programs provide a function that a user can add their own formulas for design checking or whatever so that my programs can be more widely used.
I know how to parsing equation of string form to multiple variables in code so I can compute what I want. However, I really have no idea that how to display own text editor. I think it can't be done by textbox and only thing I can think of is using opengl api. But I believe there should be easier and efficient way to this job done.
My programs are currently run on windows only but I'm planning to make OSX version and web version as well. I don't mind if solution only available for windows only or not. If anyone knows easy way to display own text-box, please help me. I will really appreciate for it. Thanks for reading my question.

Display a .dot file inside a Qt application

I am new to Qt and C++... Now, I am writing an application in Qt, in which I have to display an already generated .dot file inside my application. I tried the render function but did not work for me.. Can anyone out there help me in this regard..
Thanks
Had the same problem using Python. I came up with this solution:
svg_string = dot_graph.create_svg(prog='dot')
svgWidget = QtSvg.QSvgWidget()
svgWidget.load(QtCore.QByteArray(svg_string))
Guess you can do something similar in C++
Plotting directly a dot file requires to be able to display the nodes in the correct positions, and link them properly. This is done by very complicated engines and is not included in the dot file, which is simply a description of the graph. Maybe there are C++/Qt libraries that take dot files as an input, but I don't know them.
According to this topic (Graphviz: How to go from .dot to a graph?), you can easily transform a dot file into a png or svg file. If you want to display the rendered graph into your application, the easiest thing to do is to generate that png picture (from the shell or from your code) and to manipulate it from your program.
Take a look to QGraph. You will need much more work to make your graphs interactive.
Anyway, if you are new to Qt, even the simple display it's a steep introduction to graphics.
I have my own implementation, but I'm sorry it's not yet ready for publishing - I will do in a SWI-Prolog context...

R statistics console in QT

I am planning to link a Qt project against R to provide some statistical funcionality. I thought it might be quite cute to add some generality to the project by having an R console as a Qt widget within the tab to allow me to do analyses that I haven't thought of in the design stage later on. I was wondering whether it is something that might be accomplished fairly easily?
In particular I'm stuck on how I would access the RTerm from QT? Has anyone else attempted something similar or can give some hints on where to start?
One of the examples for RInside does something pretty close---in around 200 lines most of which deal with the other GUI aspects, it wraps R functionality inside a Qt application.
The example implements a GUI density slider, and the edit box allows you to write an almost arbitrary R expression, or rather the parts that are then passed into an evaluation to generate random number: rnorm(50), or for a mixture c(rnorm(50), rt(50)) etc. You could possibly build on top of that.
See this blog post for more.
Check out Carson Farmer's work on manageR:
http://www.ftools.ca/manageR/
this is a plugin for Quantum GIS (mapping package) that interfaces it to R, giving you exactly what you want - an R console wrapped in a Qt4 body - as well as data transfer between Qgis and R. It handles plots as well.
I've tried to encourage Carson to produce a standalone R Gui project from this code, but he's a busy guy. Aren't we all?
RStudio is largely written using QT, you should be able to have a look at their code and build something similar into your Qt based application:
https://github.com/rstudio/rstudio

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.

SQLite with MFC

I want to use SQLite within my MFC application.
for that, i'll create an object whose job is to interact directly with the DB(SQLite) to insulate the rest of the app from the DB code.
can anyone point me to a good tutorial ?
i'll need operations such as (create,delete,insert,update,createdb,dropdb and so on...)
Thanks.
There's a page in the SQLite site that lists many available wrappers - here. The C++ wrapper Daniel mentions in his answer is probably the most common one, though it does not support Unicode and the SQLite dll that comes with it is quite dated. There's a Unicode version of that wrapper here, but it's a bit buggy and requires some more work. It could, however, save you the trouble of writing the whole thing from scratch.
Have a look at this. This was really easy to port to MFC classes, but it will get you started.
http://www.codeproject.com/KB/database/CppSQLite.aspx
Or you can just do #include "sqlite3.h", add sqlite3.lib to your linker and use sqlite3.dll directly with the C api. That's what I did in my MFC app.
And you can even statically link sqlite3 into your app. Download the amalgamation and include it! It adds about 400 k.
Please define your problem more clearly.
sqlite can be coding with c, and you can read the sample in their site.

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