Re: GWorkspace openFile & ImageViewer

[Richard Frith-Macdonald]

Marko Riedel wrote:

> Hi folks,
>
> I am trying to get GPSText to open PS and PDF files when they are
> double-clicked in the workspace browser. This was suggested to me by
> Nicolas Roard.
>
> I found that GWorkspace launches the application correctly, but it
> repeats the file name among the command line arguments. My application
> parses these as well, so that it opens the file twice. (I could fix
> this by checking whether the file has already been opened, but I would
> prefer to understand what exactly is happening.) I have also noticed
> that GWorkspace tries to lauch a second copy of the application when I
> click on a second file, whereas it should message the process that is
> already running to open the file.
>
> I was curious to know whether my code was the problem, so I compiled
> and installed ImageViewer. It seems to have the same problem: open a
> TIFF file and the app launches, open a second file and GWorkspace does
> not message the process that is already running and tries to launch
> another copy of ImageViewer instead.
>  
>
> Maybe someone can help me out here.
The application delegate (in your case it's your Controller class) needs 
to support the standard file handling methods which the workspace will 
send to it to ask it to handle a file operation.

These are ...
-application:openFile:
-application:openFileWithoutUI:
-application:openTempFile:
-application:printFile:

Just to get it to open files from GWorkspace you probably only need to 
implement the first of these.

You also need to have GPSTextInfo.plist contain information telling the 
system which file extensions the application is able to open ... if the 
app is installed in one of the standard locations (make install should 
do that) and the make_services tool is run to update the caches, then 
NSWorkspace should know to use it to open the files, and should send the 
-application:openFile: message to it.