Celestin Apprentice 2

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Text File | 1992-11-29 | 10.2 KB | 264 lines | [TEXT/MSET]

MOPS WINDOWS and EVENTS ********* IMPORTANT OBJECTS, VECTS, and VALUEs fevent class event themouse class mouse mbaddr class dicaddr will be sent click: messages by fevent wnd A value, contains the wptr of the window we are looking at. This will be set by a call to FindWindow in the mousedown handler or by FrontWindow in the key event handler. Note that fevent will send messages to this window. ActW A value, identifies any active active Mops window which should be idled Will be set to zero if we have, say, a dialog as the front window, but NOT if we're switched into the background. SaveActW A value, Saves Actw over suspend/resume. ********** Mops Event Loop Explained Normally, Mops should be in a loop something like the following if you want your program to repsond to keyboard input: BEGIN key \ key polls events and performs all default behavior \ while waiting for a key to be pressed actW IF key: actW \ pass keystroke to our window ELSE drop \ not our window, so drop the keystroke THEN AGAIN ; But be careful. Once you have put Mops in the above loop you won't be able to type commands from the console window. Class window, which is the class of fwind (the console) responds to key: messages by doing nothing. One solution would be to set a menu handler to grab Mops's attention by executing SP!. Or one could use Quick Edit, if you are using System 7, to communicate with Mops even while it is in the above loop. From Mike Hore: actW is the value that "officially" holds the addr of the frontmost Mops window, or is zero if there isn't one. wnd is just temporary storage. It's normally the same as actW, but needn't be. If, say, your application has a "normal" window and also another window with status information or something, you might not want the status window to become active even if it's clicked on. But wnd holds the addr of any window clicked on, no matter what. The above loop will work even if you have no windows open at all. key is merely doing the following: key: fevent ( c mods) drop $ ff and ( c' ) fevent is an instance of the EVENT class which is basically an X-ARRAY, with some additional data and methods, which when sent the key: message will get the next event from the Mac system and execute the appropriate handler in fevent. fevent is loaded with 23 event handlers (see file Objinit) as follows: event# fevent Mac Toolbox Late Bound handler equate Messages to wnd or ActW or mbaddr ------ --------- ----------- ----------------- 0 null-evt nullEvt idle: ActW 1 mouse-evt mButDwnEvt content: wnd click: mbaddr drag: wnd grow: wnd close: wnd zoom: wnd 2 null-evt mButUpEvt 3 key-evt keyDwnEvt key: mbaddr 4 null-evt keyUpEvt 5 key-evt autoKeyEvt 6 upd-evt updatEvt draw: wnd 7 disk-evt diskInsertEvt 8 actv-evt activateEvt enable: wnd disable: wnd 9 null-evt not used 10 null-evt networkEvt 11 null-evt ioDrvrEvt 12 null-evt app1Evt 13 null-evt app2Evt 14 null-evt app3Evt 15 null-evt osEvt (was app4Evt) see IM-VI 5-19 enable: wnd disable: wnd 16 null-evt not used 17 null-evt not used 18 null-evt not used 19 null-evt not used 20 null-evt not used 21 null-evt not used 22 null-evt not used 23 HL-evt kHighLevelEvent see IM-VI 5-21 It is easy to change any of these event handlers at any time, since we can just define a word, tick its cfa, and store into fevent: ' new-evt-handler 4 to: fevent \ set a handler for key up events The event handlers in fevent will send late bound messages to wnd. FEVENT ACTION HANDLERS -MODELESS -- Sets normal event handling - no modeless dialogs, by storing the appropriate 23 event handlers in the event object fevent. ACTV-EVT -- false Handles activate and deactivate events by sending a late bound enable:and disable: messages to the current window (but only if it is an application window). DISK-EVT -- false Handles a disk insert event. HL-EVT -- falseHandles High-level events. Several vects are involved. KEY-EVT -- keywd modswd T | -- F Gets key value if true. Handles command-key menu actions. Does not handle "normal" key actions, that is up to your code. MOUSE-EVT -- false Handles mouse events. NULL-EVT -- false Will send late bound idle: to the actW, if it is non-zero. OS-EVT -- false Handles operating system events by calling various vects. UPD-EVT -- false Handles update events by sending a late bound draw: message to the current window (but only if it is an application window). APPWIND? -- b True if this is an application window. This check is necessary for non-multifinder systems while calling WaitNextEvent. KEY -- c A system vector. The action of key is normally (key). (key!) is used to set the default action for key. (KEY!) -- Sets the default action for vect key by storing the cfa of (key) in it. (KEY) -- c The default action for key. c is the character corresponding to the key that was pressed. : (key) key: fevent drop $ FF and ; (PAUSE) -- Our standard action for the vect pause. ?EVENT eventMask -- b Calls the Toolbox Event Manager routine EventAvail to test for the event(s) specified by eventMask. If an event is available, leaves a true flag; otherwise, leaves a false flag. ?PAUSE -- ?TERMINAL -- Performs a 40 ?Event. This word is used in class Mouse, and in the utility word ?pause to test for a keyboard event. APPLE EVENTS (AEErr) err# -- Default for error returns from AppleEvent handlers, i.e. this is the action for AEErrorVec. AEErrorVec -- A vect. Called when an AppleEvent handler returns. Default is (AEerr). AEhandler ^AE ^AEReply RefCon -- Put at the start of an AppleEvent handler proc. Pops the parms into the appropriate locations. AppleEvents? -- b A value. Set True by the startup code if AppleEvents are available. ?RTNAEPMISSED w:xx rc -- w:rc' This can be called after calling GotParms? to convert the return code from that word to the appropriate return code to return to the caller of the handler. If GotParms? returns false, that means we missed a parm, so we return -1715. If GotParms? returned anything non-zero, that means we got all the parms, so we return zero. doAEhandler ^AE ^AEReply RefCon -- Called from AEhandler to set things up at the start of a handler. FAE -- ^AE A value used to handle AppleEents. HLEventVEC -- A vect. Called for generic high-level events. Default is vfalse. MISCELLANEOUS #docsToOpen -- n A value. BECOME -- : word BECOME allows restarting at a given word, with all stacks empty. This is necessary in menu handlers and other areas that could create indefinite nesting situations. CvtClip -- A vect. Called for clip conversion. DBLTICKS -- n Returns the double-click interval in ticks via the Mac global variable DoubleTime. DESK -- Desktop click handler - do nothing. FIND-WINDOW Tpoint -- region ^window Calls the Window Manager routine FindWindow to find the window in which a mouse-down event occurred at Tpoint, a Toolbox point in global coordinates. Leaves the region of the window in which the mouse-down occurred and ^window, the pointer to the window object's private data. GOTPARMS? -- rc This can be called at the end of a handler, to check if we got all the parameters. MouseMoved -- A vect. Called for mouse moved. NEXTEVENT ^event mask -- b We call WaitNextEvent if it's available, otherwise GetNextEvent. NEXT_TASK -- A vect. If multitasking is installed, this will be redirected to do a task switch. OpenAppVec -- code True | -- False As set up in Mops, OpenAppVec simply returns False and does nothing else. OpenDocHandler ? Normal :PROC entry sequence to set up the Mops addressing environment OpenDocVec -- code True | -- False OpenDocVec finds the number of files in the given list of files, and puts the number in the value #DocsToOpen. It then handles each file in the given list fFcb, then calling the sufficient for your appropriately. OpenMopsDic ? OpenMopsDic is the default for OpenDocVec. PAUSE -- A system vector, normally contains (pause), defined in file Frontend. PAUSE should be called at strategic intervals in all applications, unless Key is being called frequently. Pause normally calls next: fEvent which allows a task switch to be done under MultiFinder, and which also handles any pending events for this task, such as window updates. Remember to disable any menus etc. that you don't want to execute in this situation! Unexpected re-entrancy is a good way to bomb! PrintDocHandler ? Normal :PROC entry sequence to set up the Mops addressing environment QuitAppHandler ? Normal :PROC entry sequence to set up the Mops addressing environment QuitAppVec -- code True | -- False The current setting for QuitAppVec is simply to call BYE. Your application will probably want to do something a bit more intelligent. Read1DocVec -- code True | -- False As set up, Read1DocVec assumes the file is a Mops dictionary. Read1DocVec must point to a routine which will read the file designated by the file object fFcb, close it, and return a result on the stack. True indicates the OpenDocVec loop can continue. False means the loop must terminate. You could return False, for example, on an error, or simply if your application can't accept more than one document open at a time. RESUME? -- b A value. True if we've just received a Resume event. ResumeVec -- A vect. Called for resume. SaveActW -- wptr Saves actW over Suspend-Resume. SLEEPTICKS -- n A value. Used in calls to WaitNextEvent. Default is 20 as set by file Frontend. STILLDOWN? -- b A direct call to StillDown. Returns true if mouse button is still down. SUSPEND? -- b A value. True if we've just received a Suspend event. SuspendVec -- A vect. Called for suspend. SYS wptr -- System click handler, a direct call to SystemClick. THEDLG -- addr A variable. THEPOINT -- addr A variable. WAITCLICK -- Waits until a mouse click or key event. WHRFEV -- point Will become where: fEvent . WNEavail? -- b A value. Set True by the startup code if the WaitNextEvent trap is available in the System being used.