2 * Copyright (c) 1999-2009 Nokia Corporation and/or its subsidiary(-ies).
4 * This component and the accompanying materials are made available
5 * under the terms of "Eclipse Public License v1.0"
6 * which accompanies this distribution, and is available
7 * at the URL "http://www.eclipse.org/legal/epl-v10.html".
9 * Initial Contributors:
10 * Nokia Corporation - initial contribution.
15 * FORM global parameters; held in thread-local storage.
20 #ifndef __FRMPARAM_H__
21 #define __FRMPARAM_H__
27 Specifies the protocol for getting system colours for use in text views. A
28 class which implements this protocol allows an application (or a thread,
29 because a pointer to the object is held in thread-local storage) to use system
30 colours in text views.
32 You should create an object of an MFormParam-derived class which implements the
33 SystemColor() function. Then, pass a pointer to the object to the static
34 function MFormParam::Set(). The MFormParam-derived object is owned by the
35 caller of Set(). When system colours are no longer needed, you should cancel
36 them by calling MFormParam::Set(NULL). It is the caller's responsibility to
37 cause the text view to be redrawn after system colours are changed.
39 CTextLayout uses the colour translation function SystemColor() (if an
40 MFormParam-derived object is present) to set the pen and brush colours for
41 drawing components of the text view. It calls MFormParam::Get() before each
42 draw. This enables an application to introduce system colours, change the
43 parameter object, or abolish system colours, and redraw everything correctly;
44 no information is left over from the last draw.
53 /** Translates 8-bit logical colour indices to physical colours pure
56 The colour index is stored in a TLogicalRgb object and is returned by
57 TLogicalRgb::SystemColorIndex().
59 There are three reserved index values:
61 Zero means the logical colour does not map to a system colour: the logical
62 colour is in fact an ordinary TRgb. This function should not normally be
63 called with this value.
65 254 and 255 are default foreground and background colours respectively, and
66 should be converted to the GUI's standard foreground and background colours
68 The values 1-253 are reserved for the use of the GUI and can be interpreted
69 as convenient. These can be interpreted as
70 TLogicalColor::EColorWindowBackground upward; this mapping can be done by
71 subtracting one from the index number aColorIndex.
73 @param aColorIndex Logical colour index. Between 1 and 255 inclusive.
74 @param aDefaultColor The default colour. This is the colour to be used if
75 no translation is performed. This allows translation to change certain
76 indices but not others, (by passing the default colour back unchanged).
77 @return The physical colour which maps to the logical colour index. */
78 virtual TRgb SystemColor(TUint aColorIndex,TRgb aDefaultColor) const = 0;
79 IMPORT_C virtual void Reserved();
80 IMPORT_C static void Set(const MFormParam* aParam);
81 IMPORT_C static const MFormParam* Get();
84 #endif // __FRMPARAM_H__