/////////////////////////////////////////////////////////////////////////////
-// Name: scrolling
+// Name: scrolling.h
// Purpose: topic overview
// Author: wxWidgets team
// RCS-ID: $Id$
-// Licence: wxWindows license
+// Licence: wxWindows licence
/////////////////////////////////////////////////////////////////////////////
-/*!
+/**
- @page scrolling_overview Scrolling overview
+@page overview_scrolling Scrolled Windows
- Classes: #wxWindow, #wxScrolledWindow, #wxIcon, #wxScrollBar.
- Scrollbars come in various guises in wxWidgets. All windows have the potential
- to show a vertical scrollbar and/or a horizontal scrollbar: it is a basic capability of a window.
- However, in practice, not all windows do make use of scrollbars, such as a single-line wxTextCtrl.
- Because any class derived from #wxWindow may have scrollbars,
- there are functions to manipulate the scrollbars and event handlers to intercept
- scroll events. But just because a window generates a scroll event, doesn't mean
- that the window necessarily handles it and physically scrolls the window. The base class
- wxWindow in fact doesn't have any default functionality to handle scroll events.
- If you created a wxWindow object with scrollbars, and then clicked on the scrollbars, nothing
- at all would happen. This is deliberate, because the @e interpretation of scroll
- events varies from one window class to another.
- #wxScrolledWindow (formerly wxCanvas) is an example of a window that
- adds functionality to make scrolling really work. It assumes that scrolling happens in
- consistent units, not different-sized jumps, and that page size is represented
- by the visible portion of the window. It is suited to drawing applications, but perhaps
- not so suitable for a sophisticated editor in which the amount scrolled may vary according
- to the size of text on a given line. For this, you would derive from wxWindow and
- implement scrolling yourself. #wxGrid is an example of a class
- that implements its own scrolling, largely because columns and rows can vary in size.
- @b The scrollbar model
- The function wxWindow::SetScrollbar gives a clue about
- the way a scrollbar is modeled. This function takes the following arguments:
+Classes: wxWindow, wxScrolledWindow, wxScrollBar
+@li @ref overview_scrolling_model
+@li @ref overview_scrolling_example
+<hr>
+Scrollbars come in various guises in wxWidgets. All windows have the potential
+to show a vertical scrollbar and/or a horizontal scrollbar: it is a basic
+capability of a window. However, in practice, not all windows do make use of
+scrollbars, such as a single-line wxTextCtrl.
+Because any class derived from wxWindow may have scrollbars, there are
+functions to manipulate the scrollbars and event handlers to intercept scroll
+events. But just because a window generates a scroll event, doesn't mean that
+the window necessarily handles it and physically scrolls the window. The base
+class wxWindow in fact doesn't have any default functionality to handle scroll
+events. If you created a wxWindow object with scrollbars, and then clicked on
+the scrollbars, nothing at all would happen. This is deliberate, because the
+@e interpretation of scroll events varies from one window class to another.
- orientation
+::wxScrolledWindow (formerly wxCanvas) is an example of a window that adds
+functionality to make scrolling really work. It assumes that scrolling happens
+in consistent units, not different-sized jumps, and that page size is
+represented by the visible portion of the window. It is suited to drawing
+applications, but perhaps not so suitable for a sophisticated editor in which
+the amount scrolled may vary according to the size of text on a given line. For
+this, you would derive from wxWindow and implement scrolling yourself. wxGrid
+is an example of a class that implements its own scrolling, largely because
+columns and rows can vary in size.
+@section overview_scrolling_model The Scrollbar Model
+The function wxWindow::SetScrollbar gives a clue about the way a scrollbar is
+modeled. This function takes the following arguments:
- Which scrollbar: wxVERTICAL or wxHORIZONTAL.
+@beginTable
+@row2col{ @c orientation , Which scrollbar: wxVERTICAL or wxHORIZONTAL. }
+@row2col{ @c position , The position of the scrollbar in scroll units. }
+@row2col{ @c visible , The size of the visible portion of the scrollbar,
+ in scroll units. }
+@row2col{ @c range , The maximum position of the scrollbar. }
+@row2col{ @c refresh , Whether the scrollbar should be repainted. }
+@endTable
+@c orientation determines whether we're talking about the built-in horizontal
+or vertical scrollbar.
+@c position is simply the position of the 'thumb' (the bit you drag to scroll
+around). It is given in scroll units, and so is relative to the total range of
+the scrollbar.
+@c visible gives the number of scroll units that represents the portion of the
+window currently visible. Normally, a scrollbar is capable of indicating this
+visually by showing a different length of thumb.
+@c range is the maximum value of the scrollbar, where zero is the start
+position. You choose the units that suit you, so if you wanted to display text
+that has 100 lines, you would set this to 100. Note that this doesn't have to
+correspond to the number of pixels scrolled - it is up to you how you actually
+show the contents of the window.
- position
+@c refresh just indicates whether the scrollbar should be repainted immediately
+or not.
+@section overview_scrolling_example An Example
+Let's say you wish to display 50 lines of text, using the same font. The window
+is sized so that you can only see 16 lines at a time. You would use:
- The position of the scrollbar in scroll units.
+@code
+SetScrollbar(wxVERTICAL, 0, 16, 50);
+@endcode
+Note that with the window at this size, the thumb position can never go above
+50 minus 16, or 34. You can determine how many lines are currently visible by
+dividing the current view size by the character height in pixels.
+When defining your own scrollbar behaviour, you will always need to recalculate
+the scrollbar settings when the window size changes. You could therefore put
+your scrollbar calculations and SetScrollbar call into a function named
+AdjustScrollbars, which can be called initially and also from your wxSizeEvent
+handler function.
-
-
- visible
-
-
-
-
- The size of the visible portion of the scrollbar, in scroll units.
-
-
-
-
-
- range
-
-
-
-
- The maximum position of the scrollbar.
-
-
-
-
-
- refresh
-
-
-
-
- Whether the scrollbar should be repainted.
-
-
-
-
- @e orientation determines whether we're talking about
- the built-in horizontal or vertical scrollbar.
- @e position is simply the position of the 'thumb' (the bit you drag to scroll around).
- It is given in scroll units, and so is relative to the total range of the scrollbar.
- @e visible gives the number of scroll units that represents the portion of the
- window currently visible. Normally, a scrollbar is capable of indicating this visually
- by showing a different length of thumb.
- @e range is the maximum value of the scrollbar, where zero is the start
- position. You choose the units that suit you,
- so if you wanted to display text that has 100 lines, you would set this to 100.
- Note that this doesn't have to correspond to the number of pixels scrolled - it is
- up to you how you actually show the contents of the window.
- @e refresh just indicates whether the scrollbar should be repainted immediately or not.
- @b An example
- Let's say you wish to display 50 lines of text, using the same font.
- The window is sized so that you can only see 16 lines at a time.
- You would use:
-
- @code
- SetScrollbar(wxVERTICAL, 0, 16, 50);
- @endcode
-
-
- Note that with the window at this size, the thumb position can never go
- above 50 minus 16, or 34.
- You can determine how many lines are currently visible by dividing the current view
- size by the character height in pixels.
- When defining your own scrollbar behaviour, you will always need to recalculate
- the scrollbar settings when the window size changes. You could therefore put your
- scrollbar calculations and SetScrollbar
- call into a function named AdjustScrollbars, which can be called initially and also
- from your #wxSizeEvent handler function.
-
- */
-
+*/
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