I am a beginner in GNOME desktop application development so I am trying to learn about it as much as possible. I have read various tutorials present on developer.gnome.org written for JavaScript. I know that through GObject Introspection I can access C libraries in JavaScript.
As use of JavaScript for desktop applications is new so not many documentations are present. I was wondering if there is any way I can know which functions I can use with what parameters to access some libraries.
For example I can create a button using GTK in JavaScript by:
this.mybutton = new GTK.Button({some code here});
How can I come to know about the name of the functions I can use? Is there any way I can make out the name of the function for JavaScript seeing the documentation written for C?
For some of the libraries I have seen this documentation written for JavaScript. Any help will be appreciated to understand more about GNOME application development.
I agree with you: the documentation is pretty low on the subject.
Most of the time I try to find already written code from other developers and change it to have what I want.
The C documentation is pretty complete on http://developer.gnome.org and most of the time you can use nearly the same methods.
I suggest you to take a look at this web site: http://www.roojs.org/seed/gir-1.2-gtk-3.0/seed/
And also to this one: http://zetcode.com/gui/javascriptgtktutorial/
Good luck with your javascript development !!!
There is new host for Gnome GJS documentation:
https://gjs.guide/
https://gjs-docs.gnome.org/ for API's
You still can get Javascript function mapped to the that C library function by searching though GIR files. Each library should have an XML file containing introspection information.
Example from one question I asked before.
grep -rn gdk_keymap_get_default /usr/share/gir-1.0/
/usr/share/gir-1.0/Gdk-2.0.gir:16781: c:identifier="gdk_keymap_get_default"
/usr/share/gir-1.0/Gdk-3.0.gir:15776: <function name="get_default" c:identifier="gdk_keymap_get_default">
vim /usr/share/gir-1.0/Gdk-3.0.gir +15776
<class name="Keymap"
c:symbol-prefix="keymap"
c:type="GdkKeymap"
parent="GObject.Object"
glib:type-name="GdkKeymap"
glib:get-type="gdk_keymap_get_type">
<doc xml:space="preserve">A #GdkKeymap defines the translation from keyboard state
(including a hardware key, a modifier mask, and active keyboard group)
to a keyval. This translation has two phases. The first phase is
to determine the effective keyboard group and level for the keyboard
state; the second phase is to look up the keycode/group/level triplet
in the keymap and see what keyval it corresponds to.</doc>
<function name="get_default" c:identifier="gdk_keymap_get_default">
<doc xml:space="preserve">Returns the #GdkKeymap attached to the default display.</doc>
<return-value transfer-ownership="none">
<doc xml:space="preserve">the #GdkKeymap attached to the default display.</doc>
<type name="Keymap" c:type="GdkKeymap*"/>
</return-value>
</function>
Related
Let's say we have some proprietary web components which were designed and developed for a specific company needs.
Can we safeguard our web components from being used by others? If yes, how?
Note: I am not talking about other developers modifying the component, I am only thinking about others using them straight away in the first place.
It is just JS. All you can do is delay hackers.
The most you can do is use tools like JSObfuscator and JSFuck to make your code as unreadable as possible. But ofcourse experienced hackers have tools also...
Then it dawned me; it is all about adding extra hurdles, and there is one more hurdle we can call to action.
I wrote a nerdy DEV.to blog post about using the URI to encode your Web Components
Basically boils down to NOT putting the Dictionary in the file itself, like Obfuscators do;
but placing the encoding dictionary in the URI (Domain Path even better!):
<script src="element.js?-customElements-define-HTMLElement-"></script>
And executing:
let D = document.currentScript.src.split`-`;
// D = ["element.js?","customElements","define","HTMLElement"];
window[D[1]][D[2]]("my-element",class extends window[D[3]]{ ... });
"Tab"ing the REPL gives me a list of functions, but often working with multiple languages, I forget the signature of common functions like fs.open, etc. Is there anyway to show these in the REPL?
Thanks to auto-complete in editors, they seem to be fine. But REPL for writing some quick script, I have pull up the node documentation each time for simple things.
Is there a better way to deal with this?
This semi official project developed under the node umbrella on GitHub offers a few improvement over the default REPL while used interactively:
https://github.com/nodejs/repl
Syntax highlighting is enabled for the input, basic functions signatures are displayed as hints.
As stated in this issue, its future is still uncertain, but it's already quite usable in the current state: https://github.com/nodejs/repl/issues/46
I am using NativeScript 2.0 and I would like to create an extension of an Android class like AsyncTask which contains generic parameters.
I know that I can use the extend() method to create an own implementation of a class or interface:
var myRunnable = java.lang.Runnable.extend({
action: null,
run: function() {
this.action();
}
});
But how can I do this for generic classes / interfaces in "pure" JavaScript?
You should be able to extend any interface/class using the same technique. At worst case you can extend Object. To my knowledge at this moment you can't create a interface/class from straight JS as the Java side needs something to base it off of so that the signatures are correct.
However, based on your example; if you are attempting to create a thread or runable in JavaScript; the result will currently fail horribly. NativeScript is currently a single thread, and if you attempt to cause android to attempt to jump back into JS while it is running JS, well lets just say it won't be your friend. :-)
There is a feature request and apparently this is the next big project now that 2.00 has been released. So we should see threads in the near future. There is also a plugin (disclaimer, I'm the author) called NativeScript-webworkers which can give you access to additional JS threads, but the JS threads DO NOT have the ability to interact with the OS like NS does, they are pure JS threads.
I want to write a Google Chrome extension, using ClojureScript. With ClojureScript I can use all the Google Closure libs, but afaik access to the Chrome browser is not included in those libs. So I want to wrap all the Chrome stuff in my own JavaScript lib.
So far I tried creating my own jar that has a single JavaScript file that just creates a Foo object and exports the constructor. I'v added this jar to the lib directory of the ClojureScript compiler (which also has for example goog.jar), but so far without luck:
Exception in thread "main" java.lang.IllegalArgumentException: No implementation of method: :-compile of protocol: #'cljs.closure/Compilable found for class: nil
at clojure.core$_cache_protocol_fn.invoke(core_deftype.clj:494)
at cljs.closure$eval1056$fn__1057$G__1047__1064.invoke(closure.clj:187)
at cljs.closure$get_compiled_cljs.invoke(closure.clj:422)
at cljs.closure$cljs_dependencies.invoke(closure.clj:440)
at cljs.closure$add_dependencies.doInvoke(closure.clj:462)
at clojure.lang.RestFn.applyTo(RestFn.java:139)
at clojure.core$apply.invoke(core.clj:602)
at cljs.closure$build.invoke(closure.clj:701)
at user$eval1246.invoke(cljsc.clj:21)
at clojure.lang.Compiler.eval(Compiler.java:6406)
at clojure.lang.Compiler.load(Compiler.java:6843)
at clojure.lang.Compiler.loadFile(Compiler.java:6804)
at clojure.main$load_script.invoke(main.clj:282)
at clojure.main$script_opt.invoke(main.clj:342)
at clojure.main$main.doInvoke(main.clj:426)
at clojure.lang.RestFn.invoke(RestFn.java:421)
at clojure.lang.Var.invoke(Var.java:405)
at clojure.lang.AFn.applyToHelper(AFn.java:163)
at clojure.lang.Var.applyTo(Var.java:518)
at clojure.main.main(main.java:37)
Has anyone tried this before?
Take a look at this post from Luke Vanderhart: "Using JavaScript libraries in ClojureScript"
http://lukevanderhart.com/2011/09/30/using-javascript-and-clojurescript.html
Also, this video from Kevin Lynagh: "Extending JavaScript Libraries from ClojureScript"
http://www.youtube.com/watch?v=XfzXFWTT-z0
If I remember Rich Hickeys talk correctly the whole program optimization of the closure compiler needs any library code to adhere to certain coding conventions. I think he also said something of JQuery not doing this but Dojo doing this. I never did this but you might find some useful information here
I've tried some of the editors/IDEs regularly recommended for coding JavaScript (Aptana, WebStorm, ...) but none of them has a satisfying autocomplete functionality. I'm probably spoiled by Microsoft's IntelliSense for .NET. There is some JavaScript-IntelliSense in WebDeveloper, but that seems to be a stripped-down version. The best I've found so far is WebStorm, but its code completition is easily distracted by imported libraries (offering hundreds of suggestions) and identical function names.
Did I miss an editor/IDE that uses refactoring (or something else) to offer proper code completition, so that it really "knowns" what that variable-name stands for, I just put a dot behind? Or is something like this on its way?
I always recommend Komodo Edit from ActiveState (now up to version 6, with support for HTML 5 and CSS3 as well as recent versions of Javascript, PHP, etc.) Note that you may have to install addons for the languages you're working in, but you should find them through the Mozilla-like Addon manager.
Also supports jQuery and even lets you use jQuery (along with vanilla Javascript or Python) in its powerful macro IDE.
Code completion example:
<script type="application/x-javascript">
var obj = {};
obj.personnel = [{firstName:"John", lastName:"Brick", age:43},
{firstName:"Jane", lastName:"Motte", age:26}
];
// now type obj. and code completion immediately offers you "personnel"
// note: file must be saved for the app to find all members of declared
// variables, but I save about every 10 seconds so it's not a problem
</script>
The best I've found so far is
WebStorm, but its code completition is
easily distracted by imported
libraries (offering hundreds of
suggestions) and identical function
names.
This comment confuses me. If you import the libraries, and your code is using them, why is it bad to include the function names in the code completion suggestions? Wouldn't you want to have jQuery's functions included if you're using it?
If you're using Microsoft's IntelliSense with jQuery, does it stick to its guns and only show JavaScript core functions? Sounds limited to me, unable to be smart when I add libraries.
Or is something like this on it's [sic] way?
It sounds to me like you want a clairvoyant interface. I don't think it is on the way anytime soon.
By the way, "it's" == "it is"; "its" is the possessive.