Re: [Vala] Interfaces and asynchronous methods

[Tal Hadad <tal_hd hotmail com>]

"out" keyword in async method has a different approach.
See the tutorial about async method:
https://live.gnome.org/Vala/Tutorial#Asynchronous_Methods

They is there an example that look similar to yours:
  async int fetch_webpage(string url, out string text) throws IOError {
     // Fetch a webpage asynchronously and when ready return the 
     // HTTP status code and put the page contents in 'text'
     [...]
     text = result;
     return status;
  }And how to use it, and handle the output:
  fetch_webpage.begin("http://www.example.com/";, (obj, res) => {
      try {
          string text;
          var status = fetch_webpage.end(res, out text);
          // Result of call is in 'text' and 'status' ...
      } catch (IOError e) {
          // Problem ...
      }
  });I think this example answers your question.
Tal

> Date: Tue, 14 Aug 2012 11:49:15 +0200
> From: raster rastersoft com
> To: eric yorba org
> CC: vala-list gnome org
> Subject: Re: [Vala] Interfaces and asynchronous methods
>
>
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> Ok, here are the interesting pieces of the code:
>
> interface backends : GLib.Object {
> [...]
>     public abstract async BACKUP_RETVAL start_backup(out int64
> last_backup_time);
> [...]
> }
>
> private backends backend;
> var rv=this.backend.start_backup(out this.last_backup_time);
>
>
> BTW, Jim Nelson answered that I have to do something like this:
>
> run_async.begin(on_run_async_completed);
>
> /* ... */
>
> void on_run_async(AsyncResult result, Object? source) {
>     int result = run_async.end(result);
> }
>
>
> Is this correct?
>
> Thanks.
>
>
> El 14/08/12 01:10, Eric Gregory escribió:
> > On Mon, Aug 13, 2012 at 4:03 PM, rastersoft <raster rastersoft com> wrote:
> >
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> > > Hi all:
> > >
> > > I tried to define an interface with an async method, but I receive this
> > > error in the line where I try to invoke it in an object that
> implements it:
> > > backup.vala:246.14-246.43: error: invocation of void method not allowed
> > > as expression
> > >
> > > Are async methods not allowed in interfaces?
> > >
> > > Thanks.
> >
> >
> > Could you paste the code that invokes the async method in this thread?
> >
> > - Eric
>
> - -- 
> Nos leemos
>                  RASTER    (Linux user #228804)
> raster rastersoft com              http://www.rastersoft.com
>
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