/usr/share/doc/libcdk-perl/examples/fulldemo/help/scroll.help is in libcdk-perl 20130816-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 | </R>Purpose<!R>
The scroll widget allows the user to add a scrolling list in their script.
</R>Construction Options<!R>
A scroll widget is defined using the following syntax. The variable
</B>$scrollObject<!B> contains a reference to the scroll object.
<C></B>$scrollObject = new Cdk::Radio ( options );
The options are defined in the following table.
</U>Option Default Value Type Purpose<!U>
Title Required Scalar The title of the scroll list.
List Required Array Ref The list of items in the list.
Height Required Scalar The height of the scroll list.
Width Required Scalar The width of the scroll list.
Numbers False Scalar Adds numbers to the items in the list.
Highlight Reverse Scalar The attribute of the currently highlighted item.
Xpos Center Scalar This is the position of the window on the X axis.
Ypos Center Scalar This is the position of the window on the Y axis.
Box True Scalar This Boolean states whether the dialog box will have a box drawn around it.
Shadow False Scalar This Boolean states whether the dialog box will have a shadow on the box.
</R>Available Methods<!R>
</B>activate<!B>
Activation of an object means to make the object available for use. The
following example demonstrates how to activate a scroll widget.
<C></B>$returnValue = $scrollObject->activate ();
The variable </B>$returnValue<!B> will contain a integer value representing
the number of the chosen item. The numbers start at zero and go up.
</B>inject<!B>
This function injects a single character into the widget. The following
examples demonstrates how to call the inject method.
<C></B>$scrollObject->inject ( options );
The options are defined in the following table.
</U>Option Default Value Type Purpose<!U>
Shadow Required Scalar The character to inject into the widget.
If you are injecting a special character into the widget, then you can
use a pre-defined value to represent the key.
<C><#UL><#HL(12)><#TT><#HL(15)><#UR>
<C><#VL></U>Key <#VL>Key Value <!U><#VL>
<C><#VL>Left Arrow <#VL>KEY_LEFT <#VL>
<C><#VL>Right Arrow <#VL>KEY_RIGHT <#VL>
<C><#VL>Up Arrow <#VL>KEY_UP <#VL>
<C><#VL>Down Arrow <#VL>KEY_DOWN <#VL>
<C><#VL>Delete <#VL>KEY_DELETE <#VL>
<C><#VL>Backspace <#VL>KEY_BACKSPACE <#VL>
<C><#VL>Page Up <#VL>KEY_PPAGE <#VL>
<C><#VL>Page Down <#VL>KEY_NPAGE <#VL>
<C><#VL>Home <#VL>KEY_HOME <#VL>
<C><#VL>End <#VL>KEY_END <#VL>
<C><#VL>Escape <#VL>KEY_ESC <#VL>
<C><#LL><#HL(12)><#BT><#HL(15)><#LR>
</B>set<!B>
Sets or resets certain attributes or features of the widget. The following
example demonstrates how to call the set method.
<C></B>$scrollObject->set ( options );
The options are defined in the following table.
</U>Option Default Value Type Purpose<!U>
Highlight Required Scalar The attribute of the currently highlighted item.
Box True Scalar Changes the current value of the box flag.
</B>bind<!B>
The bind method binds keys to events. The binding is specific to the individual
objects. The following example demonstrates how to call the bind method.
<C></B>$scrollObject->bind ( options );
The options are defined in the following table.
</U>Option Default Value Type Purpose<!U>
Key Required Scalar This is the character to bind the event to.
Function Required Scalar This is the name of the callback function.
</B>preProcess<!B>
The </B>preProcess<!B> function sets a process to be run before the key entered
is processed. If this function returns a value of 0, then the key injected
into the widget will not be processed; otherwise the character will be
processed as normal. The following example demonstrates how to call the
preProcess method.
<C></B>$scrollObject->preProcess ( options );
The options are defined in the following table.
</U>Option Default Value Type Purpose<!U>
Function Required Scalar This is the name of the
callback function.
To create a pre-process callback the following code segment demonstrates
how to do it properly.
<C></B>$scrollObject->preProcess ('Function' => sub { callback (@_); });
Notice that the array </B>@_<!B> is passed into the function called
</B>callback<!B>. This is done because when the callback process is
called the key which was pressed is passed into the perl subroutine.
Since we nest the call-back function inside an anonymous subroutine,
we need to pass the array </B>@_<!B> to the call-back function. If
the key given to the call-back function is a non alphanumeric key
then a predefined value will be given to the function. The following
table describes the values passed into the function.
<C><#UL><#HL(12)><#TT><#HL(15)><#UR>
<C><#VL></U>Key <#VL>Key Value <!U><#VL>
<C><#VL>Left Arrow <#VL>KEY_LEFT <#VL>
<C><#VL>Right Arrow <#VL>KEY_RIGHT <#VL>
<C><#VL>Up Arrow <#VL>KEY_UP <#VL>
<C><#VL>Down Arrow <#VL>KEY_DOWN <#VL>
<C><#VL>Delete <#VL>KEY_DELETE <#VL>
<C><#VL>Backspace <#VL>KEY_BACKSPACE <#VL>
<C><#VL>Page Up <#VL>KEY_PPAGE <#VL>
<C><#VL>Page Down <#VL>KEY_NPAGE <#VL>
<C><#VL>Home <#VL>KEY_HOME <#VL>
<C><#VL>End <#VL>KEY_END <#VL>
<C><#VL>Escape <#VL>KEY_ESC <#VL>
<C><#LL><#HL(12)><#BT><#HL(15)><#LR>
If the pre-process function returns a value of 0 the key hit will
not be injected into the widget. This allows the programmer to
selectively pick which characters will or will not get injected
into the widget.
The </B>postProcess<!B> function sets a process to be run before the key entered
is processed. If this function returns a value of 0, then the key injected
into the widget will not be processed; otherwise the character will be
processed as normal. The following example demonstrates how to call the
postProcess method.
<C></B>$scrollObject->postProcess ( options );
The options are defined in the following table.
</U>Option Default Value Type Purpose<!U>
Function Required Scalar This is the name of the
callback function.
To create a post-process callback the following code segment demonstrates
how to do it properly.
<C></B>$scrollObject->postProcess ('Function' => sub { callback (@_); });
Notice that the array </B>@_<!B> is passed into the function called
</B>callback<!B>. This is done because when the callback process is
called the key which was pressed is passed into the perl subroutine.
Since we nest the call-back function inside an anonymous subroutine,
we need to pass the array </B>@_<!B> to the call-back function. If
the key given to the call-back function is a non alphanumeric key
then a predefined value will be given to the function. The following
table describes the values passed into the function.
<C><#UL><#HL(12)><#TT><#HL(15)><#UR>
<C><#VL></U>Key <#VL>Key Value <!U><#VL>
<C><#VL>Left Arrow <#VL>KEY_LEFT <#VL>
<C><#VL>Right Arrow <#VL>KEY_RIGHT <#VL>
<C><#VL>Up Arrow <#VL>KEY_UP <#VL>
<C><#VL>Down Arrow <#VL>KEY_DOWN <#VL>
<C><#VL>Delete <#VL>KEY_DELETE <#VL>
<C><#VL>Backspace <#VL>KEY_BACKSPACE <#VL>
<C><#VL>Page Up <#VL>KEY_PPAGE <#VL>
<C><#VL>Page Down <#VL>KEY_NPAGE <#VL>
<C><#VL>Home <#VL>KEY_HOME <#VL>
<C><#VL>End <#VL>KEY_END <#VL>
<C><#VL>Escape <#VL>KEY_ESC <#VL>
<C><#LL><#HL(12)><#BT><#HL(15)><#LR>
</B>draw<!B>
This method draws the object on the screen. The following example demonstrates
how to call the draw method.
<C></B>$scrollObject->draw ( options );
The options are defined in the following table.
</U>Option Default Value Type Purpose<!U>
Box True Scalar Draws the window with a box around it.
</B>erase<!B>
This method removes the object from the screen. This does </B/U>NOT<!B!U>
destroy the object. The following example demonstrates how to call the erase
method.
<C></B>$scrollObject->erase ();
</B>raise<!B>
The raise method raises the widget to the top of the screen. This means if there
were any widgets obscuring part of the view, raising the object would bring the
complete object into view. The following example demonstrates how to call the
raise method.
<C></B>$scrollObject->raise();
</B>lower<!B>
The lower method lowers the object so it doesn't obscure the view of any other
objects. The following example demonstrates how to call the lower method.
<C></B>$scrollObject->lower();
</B>register<!B>
The register method registers the object to the default screen. This does </R>NOT<!R>
have to be called since the objects are registered automatically. This method
should be called if the </B>unregister<!B> method was called. The following
example demonstrates how to call the register method.
<C></B>$scrollObject->register();
</B>unregister<!B>
The unregister method should be called when a widget, which is part of the
default screen, needs to be taken away temporarily. This does not delete or free
the object, it just unmaps it from any future screen refreshes. The object can
be registered by calling the </B>register<!B> method. The following example
demonstrates how to call the unregister method.
<C></B>$scrollObject->unregister();
</B>getwin<!B>
This method returns a pointer to the window of the object. Not much use for this
yet. It will be useful in the future when the drawing methods are added. The
following example demonstrates how to call the getwin method.
<C></B>$scrollObject->getwin();
</R>Default Key Bindings<!R>
</U>Key Action<!U>
Up Arrow Moves the cursor to one item up.
Down Arrow Moves the cursor to one item down.
Right Arrow Scrolls the whole list one character to the right.
Left Arrow Scrolls the whole list one character to the left.
Previous Page Moves the complete list one screen backwards.
CTRL-B Moves the complete list one screen backwards
Next Page Moves the complete list one screen forwards.
CTRL-F Moves the complete list one screen forwards.
g Moves to the top of the list.
1 Moves to the top of the list.
G Moves to the bottom of the list.
$ Scrolls complete list as far left as possible.
| Scrolls complete list as far right as possible.
Return Exits the widget and returns the current selection.
Tab Exits the widget and returns the current selection.
Escape Exits the widget and returns undef.
CTRL-R Refreshes the screen.
</R>Tips & Tricks<!R>
<B=*>You can make the scrolling list look like a menu list by turning on
the numbers option and creating the window the size of the list. This
works best if the list isn't too long so the whole list can be shown.
</R>Physical Restrictions<!R>
</U>Restriction Value<!U>
Maximum number of items. 500
</R>Example Use Of The Widget<!R>
<F=../examples/scroll>
<C><#HL(70)>
<C>Document Created: June, 1995
<C>Document Revised: November, 1995
<C>Document Revised: March, 1996
<C>Document Revised: March, 2012
|