docs/latex/wx/tsamples.tex

   1 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
   2 %% Name:        tsamples.tex
   3 %% Purpose:     Samples description
   4 %% Author:      Vadim Zeitlin
   5 %% Modified by:
   6 %% Created:     02.11.99
   7 %% RCS-ID:      $Id$
   8 %% Copyright:   (c) wxWindows team
   9 %% Licence:     wxWindows licence
  10 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  11
  12 \section{wxWindows samples}\label{samples}
  13
  14 Probably the best way to learn wxWindows is by reading the source of some 50+
  15 samples provided with it. Many aspects of wxWindows programming can be learnt
  16 from them, but sometimes it is not simple to just choose the right sample to
  17 look at. This overview aims at describing what each sample does/demonstrates to
  18 make it easier to find the relevant one if a simple grep through all sources
  19 didn't help. They also provide some notes about using the samples and what
  20 features of wxWindows are they supposed to test.
  21
  22 \subsection{Calendar sample}\label{samplecalendar}
  23
  24 This font shows the \helpref{calendar control}{wxcalendarctrl} in action. It
  25 shows how to configure the control (see the different options in the calendar
  26 menu) and also how to process the notifications from it.
  27
  28 \subsection{Checklist sample}\label{samplechecklist}
  29
  30 This sample demonstrates the use of the \helpref{wxCheckListBox}{wxchecklistbox}
  31 class intercepting check, select and double click events. It also tests the
  32 use of various methods modifiying the control, such as by deleting items
  33 from it or inserting new once (these fucntions are actually implememted in
  34 the parent class \helpref{wxListBox}{wxlistbox} so the sample tests that class
  35 as well). The layout of the dialog is created using a \helpref{wxBoxSizer}{wxboxsizer}
  36 demonstrating a simple dynamic layout.
  37
  38 \subsection{Config sample}\label{sampleconfig}
  39
  40 This sample demonstrates the \helpref{wxConfig}{wxconfigbase} classes in a platform
  41 indepedent way, i.e. it uses text based files to store a given configuration under
  42 Unix and uses the Registry under Windows.
  43
  44 See \helpref{wxConfig overview}{wxconfigoverview} for the descriptions of all
  45 features of this class.
  46
  47 \subsection{Dialogs sample}\label{sampledialogs}
  48
  49 This sample shows how to use the common dialogs available from wxWindows. These
  50 dialogs are desrcibed in details in the \helpref{Common dialogs overview}{commondialogsoverview}.
  51
  52 \subsection{Scroll subwindow sample}\label{samplescrollsub}
  53
  54 This sample demonstrates the use of the \helpref{wxScrolledWindow}{wxscrolledwindow}
  55 class including placing subwindows into it and drawing simple graphics. It uses the
  56 \helpref{SetTargetWindow}{wxscrolledwindowsettargetwindow} method and thus the effect
  57 of scrolling does not show in the scrolled window itself, but in one of its subwindows.
  58
  59 Additionally, this samples demonstrates how to optimize drawing operations in wxWindows,
  60 in particular using the \helpref{wxWindow::IsExposed}{wxwindowisexposed} method with
  61 the aim to prevent unnecessary drawing in the window and thus reducing or removing
  62 flicker on screen.
  63
  64 \subsection{Font sample}\label{samplefont}
  65
  66 The font sample demonstrates \helpref{wxFont}{wxfont},
  67 \helpref{wxFontEnumerator}{wxfontenumerator} and
  68 \helpref{wxFontMapper}{wxfontmapper} classes. It allows you to see the fonts
  69 available (to wxWindows) on the computer and shows all characters of the
  70 chosen font as well.
  71
  72 \subsection{DnD sample}\label{samplednd}
  73
  74 This sample shows both clipboard and drag and drop in action. It is quite non
  75 trivial and may be safely used as a basis for implementing the clipboard and
  76 drag and drop operations in a real-life program.
  77
  78 When you run the sample, its screen is split in several parts. On the top,
  79 there are two listboxes which show the standard derivations of
  80 \helpref{wxDropTarget}{wxdroptarget}:
  81 \helpref{wxTextDropTarget}{wxtextdroptarget} and
  82 \helpref{wxFileDropTarget}{wxfiledroptarget}.
  83
  84 The middle of the sample window is taken by the log window which shows what is
  85 going on (of course, this only works in debug builds) and may be helpful to see
  86 the sequence of steps of data transfer.
  87
  88 Finally, the last part is used for two things: you can drag text from it to
  89 either one of the listboxes (only one will accept it) or another application
  90 and, also, bitmap pasted from clipboard will be shown there.
  91
  92 So far, everything we mentioned was implemented with minimal amount of code
  93 using standard wxWindows classes. The more advanced features are demonstrated
  94 if you create a shape frame from the main frame menu. A shape is a geometric
  95 object which has a position, size and color. It models some
  96 application-specific data in this sample. A shape object supports its own
  97 private \helpref{wxDataFormat}{wxdataformat} which means that you may cut and
  98 paste it or drag and drop (between one and the same or different shapes) from
  99 one sample instance to another (or the same). However, chances are that no
 100 other program supports this format and so shapes can also be rendered as
 101 bitmaps which allows them to be pasted/dropped in many other applications.
 102
 103 Take a look at DnDShapeDataObject class to see how you may use
 104 \helpref{wxDataObject}{wxdataobject} to achieve this.
 105
 106
 107 \subsection{HTML samples}\label{samplehtml}
 108
 109 Eight HTML samples (you can find them in directory {\tt samples/html})
 110 cover all features of HTML sub-library.
 111
 112 {\bf Test} demonstrates how to create \helpref{wxHtmlWindow}{wxhtmlwindow}
 113 and also shows most of supported HTML tags.
 114
 115 {\bf Widget} shows how you can embed ordinary controls or windows within
 116 HTML page. It also nicely explains how to write new tag handlers and extend
 117 the library to work with unsupported tags.
 118
 119 {\bf About} may give you an idea how to write good-looking about boxes.
 120
 121 {\bf Zip} demonstrates use of virtual file systems in wxHTML. The zip archives
 122 handler (ships with wxWindows) allows you to access HTML pages stored
 123 in compressed archive as if they were ordinary files.
 124
 125 {\bf Virtual} is yet another VFS demo. This one generates pages at run-time.
 126 You may find it useful if you need to display some reports in your application.
 127
 128 {\bf Printing} explains use of \helpref{wxHtmlEasyPrinting}{wxhtmleasyprinting}
 129 class which serves as as-simple-as-possible interface for printing HTML
 130 documents without much work. In fact, only few function calls are sufficient.
 131
 132 {\bf Help} and {\bf Helpview} are variations on displaying HTML help
 133 (compatible with MS HTML Help Workshop). {\it Help} shows how to embed
 134 \helpref{wxHtmlHelpController}{wxhtmlhelpcontroller} in your application
 135 while {\it Helpview} is simple tool that only pops up help window and
 136 displays help books given at command line.
 137
 138 \subsection{Thread sample}\label{samplethread}
 139
 140 This sample demonstrates the use of threads in connection with GUI programs.
 141 There are two fundamentally different ways to use threads in GUI programs and
 142 either way has to take care of the fact that the GUI library itself usually
 143 is not multi-threading safe, i.e. that it might crash if two threads try to
 144 access the GUI class simultaneously. One way to prevent that is have a normal
 145 GUI program in the main thread and some worker threads which work in the
 146 background. In order to make communication between the main thread and the
 147 worker threads possible, wxWindows offers the \helpref{wxPostEvent}{wxpostevent}
 148 function and this sample makes use of this function.
 149
 150 The other way to use a so called Mutex (such as those offered in the \helpref{wxMutex}{wxmutex}
 151 class) that prevent threads from accessing the GUI classes as long as any other
 152 thread accesses them. For this, wxWindows has the \helpref{wxMutexGuiEnter}{wxmutexguienter}
 153 and \helpref{wxMutexGuiLeave}{wxmutexguileave} functions, both of which are
 154 used and tested in the sample as well.
 155
 156 See also \helpref{Multithreading overview}{wxthreadoverview} and \helpref{wxThread}{wxthread}.
 157
 158 \subsection{Toolbar sample}\label{sampletoolbar}
 159
 160 The toolbar sample shows the \helpref{wxToolBar}{wxtoolbar} class in action.
 161
 162 The following things are demonstrated:
 163
 164 \begin{itemize}
 165
 166 \item Creating the toolbar using \helpref{wxToolBar::AddTool}{wxtoolbaraddtool}
 167 and \helpref{wxToolBar::AddControl}{wxtoolbaraddcontrol}: see
 168 MyApp::InitToolbar in the sample.
 169
 170 \item Using {\tt EVT\_UPDATE\_UI} handler for automatically enabling/disabling
 171 toolbar buttons without having to explicitly call EnableTool. This is is done
 172 in MyFrame::OnUpdateCopyAndCut.
 173
 174 \item Using \helpref{wxToolBar::DeleteTool}{wxtoolbardeletetool} and
 175 \helpref{wxToolBar::InsertTool}{wxtoolbarinserttool} to dynamically update the
 176 toolbar.
 177
 178 \end{itemize}