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1 /**************************************************************************** |
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2 ** |
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3 ** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies). |
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4 ** All rights reserved. |
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5 ** Contact: Nokia Corporation (qt-info@nokia.com) |
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6 ** |
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7 ** This file is part of the documentation of the Qt Toolkit. |
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9 ** $QT_BEGIN_LICENSE:LGPL$ |
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11 ** This file contains pre-release code and may not be distributed. |
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12 ** You may use this file in accordance with the terms and conditions |
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13 ** contained in the Technology Preview License Agreement accompanying |
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14 ** this package. |
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15 ** |
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16 ** GNU Lesser General Public License Usage |
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17 ** Alternatively, this file may be used under the terms of the GNU Lesser |
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18 ** General Public License version 2.1 as published by the Free Software |
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19 ** Foundation and appearing in the file LICENSE.LGPL included in the |
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21 ** ensure the GNU Lesser General Public License version 2.1 requirements |
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22 ** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html. |
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24 ** In addition, as a special exception, Nokia gives you certain additional |
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34 ** |
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35 ** |
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36 ** |
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37 ** |
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38 ** $QT_END_LICENSE$ |
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39 ** |
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40 ****************************************************************************/ |
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41 |
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42 /*! |
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43 \page qt-embedded-charinput.html |
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44 |
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45 \title Qt for Embedded Linux Character Input |
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46 \ingroup qt-embedded-linux |
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47 |
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48 When running a \l {Qt for Embedded Linux} application, it either runs as a |
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49 server or connects to an existing server. The keyboard driver is |
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50 loaded by the server application when it starts running, using |
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51 Qt's \l {How to Create Qt Plugins}{plugin system}. |
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52 |
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53 Internally in the client/server protocol, all system generated |
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54 events, including key events, are passed to the server application |
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55 which then propagates the event to the appropriate client. Note |
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56 that key events do not always come from a keyboard device, they |
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57 can can also be generated by the server process using input |
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58 widgets. |
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59 |
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60 \table |
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61 \header \o Input Widgets |
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62 \row |
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63 \o |
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64 |
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65 The server process may call the static QWSServer::sendKeyEvent() |
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66 function at any time. Typically, this is done by popping up a |
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67 widget that enables the user specify characters with the pointer |
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68 device. |
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69 |
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70 Note that the key input widget should not take focus since the |
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71 server would then just send the key events back to the input |
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72 widget. One way to make sure that the input widget never takes |
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73 focus is to set the Qt::Tool widget flag in the QWidget |
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74 constructor. |
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75 |
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76 The \l{Qt Extended} environment contains various input widgets such as |
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77 Handwriting Recognition and Virtual Keyboard. |
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78 |
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79 \endtable |
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80 |
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81 \tableofcontents |
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82 |
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83 \section1 Available Keyboard Drivers |
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84 |
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85 \l {Qt for Embedded Linux} provides ready-made drivers for the console |
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86 (TTY) and the standard Linux Input Subsystem (USB, PS/2, ...). Run the |
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87 \c configure script to list the available drivers: |
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88 |
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89 \snippet doc/src/snippets/code/doc_src_emb-charinput.qdoc 0 |
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90 |
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91 Note that only the console (TTY) keyboard driver handles console |
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92 switching (\bold{Ctrl+Alt+F1}, ..., \bold{Ctrl+Alt+F10}) and |
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93 termination (\bold{Ctrl+Alt+Backspace}). |
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94 |
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95 In the default Qt configuration, only the "TTY" driver is |
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96 enabled. The various drivers can be enabled and disabled using the |
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97 \c configure script. For example: |
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98 |
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99 \snippet doc/src/snippets/code/doc_src_emb-charinput.qdoc 1 |
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100 |
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101 Custom keyboard drivers can be implemented by subclassing the |
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102 QWSKeyboardHandler class and creating a keyboard driver plugin |
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103 (derived from the QKbdDriverPlugin class). The default |
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104 implementation of the QKbdDriverFactory class will automatically |
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105 detect the plugin, loading the driver into the server application |
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106 at run-time. |
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107 |
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108 \section1 Keymaps |
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109 |
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110 Starting with 4.6, \l {Qt for Embedded Linux} has gained support for |
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111 user defined keymaps. Keymap handling is supported by the built-in |
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112 keyboard drivers \c TTY and \c LinuxInput. Custom keyboard drivers can |
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113 use the existing keymap handling code via |
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114 QWSKeyboardHandler::processKeycode(). |
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115 |
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116 By default Qt will use an internal, compiled-in US keymap. |
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117 See the options below for how to load a different keymap. |
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118 |
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119 \section1 Specifying a Keyboard Driver |
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120 |
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121 To specify which driver to use, set the QWS_KEYBOARD environment |
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122 variable. For example (if the current shell is bash, ksh, zsh or |
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123 sh): |
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124 |
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125 \snippet doc/src/snippets/code/doc_src_emb-charinput.qdoc 2 |
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126 |
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127 The \c <driver> arguments are \c TTY, \c LinuxInput and \l |
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128 {QKbdDriverPlugin::keys()}{keys} identifying custom drivers, and the |
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129 driver specific options are typically a device, e.g., \c /dev/tty0. |
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130 |
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131 Multiple keyboard drivers can be specified in one go: |
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132 |
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133 \snippet doc/src/snippets/code/doc_src_emb-charinput.qdoc 3 |
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134 |
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135 Input will be read from all specified drivers. |
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136 |
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137 Currently the following options are supported by both the \c TTY and \c |
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138 LinuxInput driver: |
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139 |
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140 \table |
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141 \header \o Option \o Description |
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142 \row \o \c /dev/xxx \o |
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143 Open the specified device, instead of the driver's default device. |
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144 \row \o \c repeat-delay=<d> \o |
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145 Time (in milliseconds) until auto-repeat kicks in. |
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146 \row \o \c repeat-rate=<r> \o |
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147 Time (in milliseconds) specifying the interval between auto-repeats. |
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148 \row \o \c keymap=xx.qmap \o |
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149 File name of a keymap file in Qt's \c qmap format. See \l {kmap2qmap} |
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150 for instructions on how to create thoes files.\br Note that the file |
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151 name can of course also be the name of a QResource. |
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152 \row \o \c disable-zap \o |
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153 Disable the QWS server "Zap" shortcut \bold{Ctrl+Alt+Backspace} |
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154 \row \o \c enable-compose \o |
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155 Activate Latin-1 composing features in the built-in US keymap. You can |
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156 use the right \c AltGr or right \c Alt is used as a dead key modifier, |
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157 while \c AltGr+. is the compose key. For example: |
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158 \list |
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159 \o \c AltGr + \c " + \c u = \uuml (u with diaeresis / umlaut u) |
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160 \o \c AltGr + \c . + \c / + \c o = \oslash (slashed o) |
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161 \endlist |
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162 \endtable |
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163 |
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164 */ |