Tracker Add-on Protocol

The Tracker provides a convenient shortcut mechanism through the use of add-ons. A user can access a special add-ons menu by right clicking in the Tracker. The Tracker interacts with an add-on through the process_refs() function described below.

Tracker add-ons should be placed in /boot/home/config/add-ons/Tracker. A shortcut key can be associated with the add-on by appending a dash followed by the shortcut key to the filename of the add-on.

process_refs()

Declared in:  be/be/add-ons/tracker/TrackerAddOn.h

void process_refs(entry_ref dir_ref, BMessage *msg, void *reserved)

The Tracker calls this function when the user invokes the add-on. The current directory is found in dir_ref. msg is a standard B_REFS_RECEIVED BMessage with the "refs" array containing the entry_refs of the files selected by the user. The third argument is currently unused.

process_refs() runs in a separate thread within the Tracker's team, so if your add-on crashes, the Tracker goes too.

A simple Tracker Add-On follows. It simply takes the contents of the arguments to process_refs() and outputs them in a window.

#include <Application.h> #include <InterfaceKit.h> #include <StorageKit.h> #include <stdio.h> #include <string.h> #include <be/add-ons/tracker/TrackerAddon.h> void process_refs(entry_ref dir_ref, BMessage *msg, void *) { BWindow *window = new BWindow(BRect(100,100,300,300),    "Sample Tracker Add-on", B_TITLED_WINDOW, 0); BTextView *view = new BTextView(BRect(0,0,200,200), "view",    BRect(0,0,200,200), B_FOLLOW_ALL_SIDES, B_WILL_DRAW |    B_FULL_UPDATE_ON_RESIZE); BPath path; BEntry entry(&dir_ref); entry.GetPath(&path); view->Insert("Current Directory: "); view->Insert(path.Path()); view->Insert("n"); int refs; entry_ref file_ref; for (refs=0;msg->FindRef("refs", refs, &file_ref) == B_NO_ERROR;refs++) { if (refs == 0)       view->Insert("Selected files:n"); entry.SetTo(&file_ref); entry.GetPath(&path); view->Insert(path.Path()); view->Insert("n"); } if (refs == 0) view->Insert("No files selected.n"); view->MakeEditable(false); window->AddChild(view); window->Show(); } main() { new BApplication("application/x-sample-tracker-add-on"); (new BAlert("", "Sample Tracker Add-on", "swell"))->Go(); delete be_app; }