Good resources for using Glade [Interface Designer] with Vala seem to be very sparse, and I'm having a difficult time getting started with Glade.
I did find a tutorial that seemed pretty good last year, but Ican no longer locate it.
Basically, I want to use Glade to do the GUI stuff, and then somehow "hook" it into my Vala code. How do we do this?
Glade generates a UI description in an XML format. GTK contains a class called Gtk.Builder which reads this XML and constructs a widget hierarchy.
"Traditionally", the way to tie the two together is to give the widgets meaningful names in Glade, and then use widget = Gtk.Builder.get_object(name) to grab the widget for use in your programme. You'll find quite a few examples like this on the web (google "vala gtkbuilder" or something similar to find them).
However, the latest versions of Vala and GTK have some new features to cut out quite a bit of the boilerplate from the way things have been done in the past. It's very new so you won't find many examples yet, but this blog post has all the details:
http://blogs.gnome.org/tvb/2013/05/29/composite-templates-lands-in-vala/
at the GTK tutorial there's simple vala sample where they show how to load an xml glade file.
and for glade:
I would prefere learning how to design the gui in vala first because it will give you a better understanding of how GTK works. layouts like gtk.box and gtk.window etc.
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I am trying to create a markdown editor for fun and because I was interested in learning TextKit. I am working on iOS devices only, so I only have UIKit framework at my disposal, also I watched this WWDC18 video which explains some best practices to adopt with TextKit. At first I was really interested in knowing how to get the same result that the video shows at 22:13.
The code shown by the dev in the video makes use of AppKit and it wraps code in that rectangle by replacing the code section with a NSMutableParagraphStyle and by providing a custom NSTextBlock to the latter. As you can guess, I can't subclass NSTextBlock in UIKit and therefore I can't replicate the example shown.
I have something a little bit harder to ask though, what I really wanted to replicate is the GitHub application code block style, this is the final result that I would like to replicate:
As you can see it should have a rounded rectangle with a custom background color and also it needs to be scrollable in order to make code expand as much as it needs (I am not interested in syntax highlighting).
How can I achieve something like this if NSTextBlock is not available in UIKit?
For the moment all I have done is override NSTextStorage to set the correct font to the code section with custom NSAttributedString.
I have investigated in the app and noticed that it is managed by Ryan Nystrom which is the creator of GitHawk prior to moving to GitHub. The GitHawk markdown reader is very similar to the one that you find in the GitHub application and the funny thing is that GitHawk is open source so I took a look at that code and tried to understand how that could be replicated.
Turns out that GitHawk heavily uses IGListKit framework and parses markdown in ListDiffable elements, specifically the code blocks ListDiffables are given to a ListSectionController that created an horizontal UIScrollView to display code.
I gave up trying to understand more on this because GitHawk code is really really entangled and it is really hard, near impossible, to extract the specific functionality.
I'm creating a plugin in Quantum GIS that is using Postgres as the back end and QT Designer to make the GUI. I'm using psycopg2 to run scripts in the database and even fetch results of queries to set the values of labels in the GUI. This stuff is working fine for me.
What I would like to do now after some queries are run by clicking a 'calculate' button is for the resulting table to be shown in the plugin as a TableView. I know there widget exists expressly for the purpose of viewing tables but I can't quite figure out how to go about it. I'm not sure if I should be using psycopg2 or PySide, since most examples I have seen online use the latter.
I am wondering if someone can tell me which between psycopg2 and PySide should be used to create the TableView. Second, I am wondering what the 'signal' should be to the TableView widget to display the results of a query in Postgres. Lastly, is anyone can offer some instruction as to how to set up the code it would be hugely appreciated!
Cheers,
Roman
I've gone ahead and tried following the PyQt documentation, but as it's provided in C++ and I'm only a beginner programmer using Python I'm not sure if I've caught all the necessary amendments to the code syntax. Anyways, this is what I have so far:
db = QSqlDatabase.addDatabase("database")
db.setHostName("localhost")
db.setUserName("postgres")
db.setPassword("password")
#Not sure what to do to set the connection. The C++ documentation says to put "bool ok = db.open();"
model = QSqlQueryModel()
model.setQuery("SELECT name, density, deveff FROM public." +str(filename)+ "_rezoning ORDER BY gid;")
model.setHeaderData(0, Qt.Horizontal, "Name")
model.setHeaderData(1, Qt.Horizontal, "Density")
model.setHeaderData(2, Qt.Horizontal, "DevEff")
view = QTableView()
view.setModel(model)
view.show()
What happens when I click the button in my GUI to run the calculations, a small blank QGIS window briefly flashes and goes away. At least I'm not getting an error, but it's obviously not complete. I assume part of the issue is the connection to the database that is missing and that I do not know how to set. The other issue is that I would like this to show in the tableView widget in the GUI, but I'm not sure how to specify this...
Any further tips? I really appreciate it.
Roman
If you're planning to use Qt widgets and models, PySide (PyQt, or plain Qt/C++) is the way to go.
With bare psycopg2 you'll have a lot more work to do, and you'll need to implement your own model in order to leverage Qt's model/view classes. This is simply not the Qt way of doing things. PySide (and PyQt) has it own means to connect to a supported database, there's no need for pure Python database adapters like psycopg2. It uses the underlying libqt4-sql library (C++) and the installed plugins (QPSQL, QMYSQL, QSQLITE, etc).
Essentially you need to:
Connect to a database.
Instantiate a model (QSqlQueryModel, QSqlTableModel or a custom QAbstractTableModel derived class)
Attach that model to a view (ie. QTableView).
Take a look at the PySide QtSql Documentation and the PyQt documentation to get an idea. They're mostly compatible/interchangeable, but at a glance I see that the PyQt documentation looks more complete.
EDIT (after your edit):
A Qt GUI application requires an event loop to run, and that's provided by a QApplication instance. Before going any further with the specifics of your app, take the time to understand a few basic concepts first. Here's a nice Getting Started with PyQt Guide.
I tried the simpledroid with INotifyPropertyChanged and ICommand successfully.
I want to do the same with monotouch and xib designer,but without TouchDialog. Is there a way to implement without inheriting from mvx class as in monodroid?
Is it possible to do the same with MonoMac without Dialog as Portable Library in MonoMac or XaMac in supported now?
I understand what is your goal.
I think you want to start learning MvvmCross for Monotouch with a basic application example as you probably did with SimpleDroid. I tried to do the same without success.
Why ? Because SimpleDialogTouch is an "Advanced" example in my opinion. When you learn Monotouch, you use xib to design your view. But the sample tells you to learn a new tool "Monotouch Dialog" which is a way to display controls programmatically.
You get those errors because the sample implements the ViewModel only for Dialog and not for xib or classic binding.
Finally, you will have to dig into MvvmCross to build your own SimpleTouch implementation. The problem is that you don't have a lot of documentation, but Stuart is the best supporter for a beginner or you can switch to advanced Mvx features if you don't need to understand the underground of MvvmCross. There are a lot of samples, tutorials and posts to tweak Mvx.
Hope that helps.
Is there a way to implement without inheriting from mvx class as in monodroid?
I don't believe this is supported in the current source.
There is an effort underway to separate out the databinding code in MvvmCross so it can be used more easily with other frameworks - e.g. we might try porting MvvmLight across too. This is where my effort is currently focused.
If you need this now, then I think you could fairly easily create this simple binding yourself if you wanted to - but you'd have to take a look at what the SimpleDialog version does - it's not too big a code to copy across to the XIB version - https://github.com/slodge/MvvmCross/blob/vnext/Cirrious/Cirrious.MvvmCross.Dialog.Touch/Simple/MvxSimpleTouchDialogViewController.cs
But... why not just implement a proper portable MvxViewModel instead?
Is it possible to do the same with MonoMac without Dialog as Portable Library in MonoMac or XaMac in supported now?
Portable libraries are not supported in any release from Xamarin yet - there is an unofficial installer that Jeff very kindly provided - but it's not a release...
For MvvmCross MonoMac/XaMac support, there is one non-PCL version from #deapsquatter around, but I don't believe this has data-binding yet.
I will be working on a PCL and data-binding release for MonoMac or XaMac - but it's on a spare time basis - no-one's come forward with a customer project to fund that work yet. If you or anyone wants to assist with this port, then you are very welcome... but it will be quite technical work - there are changes I intend to make 'under the covers' - so the easiest place for others to help will probably be in later work - adding more views, more bindings, doing QA, making samples, etc.
Note: "Simple" bindings are not the future for MvvmCross and may get dropped from a future release. However, this will only happen after I've separated out the Binding code so that it can be used with other libraries - the first of which will probably be a simple binding example.
I personally don't see much difference or advantage in using these so-called Simple bindings... but maybe I'm missing something...
Does anyone know of a good tutorial or YouTube video that explains how to set up and use the Navigator in the IBM Xpages Extension Library?
It is a bit confusing with all the options, types of nodes, and Select & Submit Values. Hope to find something that shows the simple way to use this tool along with some of the Advanced capabilities.
I did a quick youtube video where I show just the simplest use of it. enjoy
http://www.youtube.com/watch?v=adtyIAo3bZE
Is there anything specific you want to know?
Hopefully a good tutorial is the XPages Extension Library book. It goes into detail on all the various node types.
Man so much has changed since I learned DirectX 7.
Everywhere I look (except Wikipedia), it says I have to render from DWrite to D2D or GDI before I can do anything.
Is that Wikipedia article wrong? Can I not render to Direct3D?
I'd like to avoid having to render to D2D, since apparently, to get D2D to write to D3D, you have to open up a D3D10.1 device as well.
Does it really take all this just to render text in D3D11?
Unfortunately, Microsoft decided to remove native text support from their DirectX API. Now you can either use DirectWrite, and then as you said render to GDI or D2D, which is somewhat clunky, or alternatively, make your own font-handling class, and use that (which is what I've chosen to done for my project).
There is a good tutorial on how to produce a custom Font-handling class, here: http://www.rastertek.com/dx11tut12.html
Obviously, you should write your own, but it provides a good starting point, and allows you to see all the necessary proceedures (something you will probably want to add will be support for multiple fonts, for which I recommend creating a Font class, which your Font-Handler stores with an associative string in a std::map< char*, Font* >).
Hope this helps! :)