1 /* This file is part of
2 * ======================================================
4 * LyX, The Document Processor
6 * Copyright 1995-2001 The LyX Team.
8 * ======================================================
14 #pragma implementation
27 #include "GTabularCreate.h"
30 bool Dialogs::tooltipsEnabled()
32 return Tooltips::enabled();
34 Dialogs::Dialogs(LyXView * lv)
36 add(new GUIUrl<FormUrl, gnomeBC>(*lv, *this));
37 add(new GUIError<FormError, gnomeBC>(*lv, *this));
38 add(new GUITabularCreate<FormTabularCreate, gnomeBC>(*lv, *this));
39 add(new GUIERT<FormERT, gnomeBC>(*lv, *this));
41 // reduce the number of connections needed in
42 // dialogs by a simple connection here.
43 hideAll.connect(hideBufferDependent.slot());
46 /*****************************************************************************
48 Q. WHY does Dialogs::Dialogs pass `this' to dialog constructors?
50 A. To avoid a segfault.
51 The dialog constructors need to connect to their
52 respective showSomeDialog signal(*) but in order to do
53 that they need to get the address of the Dialogs instance
54 from LyXView::getDialogs(). However, since the Dialogs
55 instance is still being constructed at that time
56 LyXView::getDialogs() will *not* return the correct
57 address because it hasn't finished being constructed.
58 A Catch-22 situation (or is that the chicken and the egg...).
59 So to get around the problem we pass the address of
60 the newly created Dialogs instance using `this'.
62 (*) -- I'm using signals exclusively to guarantee that the gui code
63 remains hidden from the rest of the system. In fact the only
64 header related to dialogs that anything in the non-gui-specific
65 code gets to see is Dialogs.h! Even Dialogs.h doesn't know what a
66 FormCopyright class looks like or that its even going to be used!
68 No other gui dialog headers are seen outside of the gui-specific
69 directories! This ensures that the gui is completely separate from
70 the rest of LyX. All this through the use of a few simple signals.
71 BUT, the price is that during construction we need to connect the
72 implementations show() method to the showSomeDialog signal and this
73 requires that we have an instance of Dialogs and the problem mentioned
76 Almost all other dialogs should be able to operate using the same style
77 of signalling used for Copyright. Exceptions should be handled
78 by adding a specific show or update signal. For example, spellchecker
79 needs to set the next suspect word and its options/replacements so we
81 Signal0<void> updateSpellChecker;
83 Since we would have to have a
84 Signal0<void> showSpellChecker;
86 in order to just see the spellchecker and let the user push the [Start]
87 button then the updateSpellChecker signal will make the SpellChecker
88 dialog get the new word and replacements list from LyX. If you really,
89 really wanted to you could define a signal that would pass the new
90 word and replacements:
91 Signal2<void, string, vector<string> > updateSpellChecker;
93 (or something similar) but, why bother when the spellchecker can get
94 it anyway with a LyXFunc call or two. Besides if someone extends
95 what a dialog does then they also have to change code in the rest of
96 LyX to pass more parameters or get the extra info via a function
97 call anyway. Thus reducing the independence of the two code bases.
99 We don't need a separate update signal for each dialog because most of
100 them will be changed only when the buffer is changed (either by closing
101 the current open buffer or switching to another buffer in the current
102 LyXView -- different BufferView same LyXView or same BufferView same
105 So we minimise signals but maximise independence and programming
106 simplicity, understandability and maintainability. It's also
107 extremely easy to add support for Qt or gtk-- because they use
108 signals already. Guis that use callbacks, like xforms, must have their
109 code wrapped up like that in the form_copyright.[Ch] which is awkward
110 but will at least allow multiple instances of the same dialog.
112 LyXFuncs will be used for requesting/setting LyX internal info. This
113 will ensure that scripts or LyXServer-connected applications can all
114 have access to the same calls as the internal user-interface.
116 ******************************************************************************/