AppInfo
Object Hierarchy:
Description:
Information about an installed application and methods to launch it (with file arguments).
`GAppInfo` and `GAppLaunchContext` are used for describing and launching applications installed on the system.
As of GLib 2.20, URIs will always be converted to POSIX paths (using [method@Gio.File.get_path]) when using [method@Gio.AppInfo.launch] even if the application requested an URI and not a POSIX path. For example for a desktop-file based application with Exec key `totem u` and a single URI, `sftp://foo/file.avi`, then `/home/user/.gvfs/sftp on foo/file.avi` will be passed. This will only work if a set of suitable GIO extensions (such as GVfs 2.26 compiled with FUSE support), is available and operational; if this is not the case, the URI will be passed unmodified to the application. Some URIs, such as `mailto:`, of course cannot be mapped to a POSIX path (in GVfs there's no FUSE mount for it); such URIs will be passed unmodified to the application.
Specifically for GVfs 2.26 and later, the POSIX URI will be mapped back to the GIO URI in the [iface@Gio.File] constructors (since GVfs implements the GVfs extension point). As such, if the application needs to examine the URI, it needs to use [method@Gio.File.get_uri] or similar on [iface@Gio.File]. In other words, an application cannot assume that the URI passed to e.g. [func@Gio.File.new_for_commandline_arg] is equal to the result of [method@Gio.File.get_uri]. The following snippet illustrates this:
```c GFile *f; char *uri;
file = g_file_new_for_commandline_arg (uri_from_commandline);
uri = g_file_get_uri (file); strcmp (uri, uri_from_commandline) == 0; g_free (uri);
if (g_file_has_uri_scheme (file, "cdda")) { // do something special with uri } g_object_unref (file); ```
This code will work when both `cdda://sr0/Track 1.wav` and `/home/user/.gvfs/cdda on sr0/Track 1.wav` is passed to the application. It should be noted that it's generally not safe for applications to rely on the format of a particular URIs. Different launcher applications (e.g. file managers) may have different ideas of what a given URI means.
Example: AppInfo:
public static int main (string[] args) {
try {
AppInfo appinfo = AppInfo.get_default_for_type ("text/x-vala", true);
print ("%s\n", appinfo.supports_files ().to_string ());
print ("%s\n", appinfo.supports_uris ().to_string ());
print ("%s\n", appinfo.get_commandline ());
print ("%s\n", appinfo.get_name ());
appinfo.launch (null, null);
} catch (Error e) {
print ("Error: %s\n", e.message);
}
return 0;
}valac --pkg gio-2.0 GLib.AppInfo.vala