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  1. <html><head><meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"><title>Getting Input for a Macro</title><meta name="generator" content="DocBook XSL Stylesheets V1.65.1"><link rel="home" href="index.html" title="jEdit 4.2 User's Guide"><link rel="up" href="macro-tips.html" title="Chapter 15. Macro Tips and Techniques"><link rel="previous" href="macro-tips.html" title="Chapter 15. Macro Tips and Techniques"><link rel="next" href="startup-scripts.html" title="Startup Scripts"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">Getting Input for a Macro</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="macro-tips.html">Prev</a> </td><th width="60%" align="center">Chapter 15. Macro Tips and Techniques</th><td width="20%" align="right"> <a accesskey="n" href="startup-scripts.html">Next</a></td></tr></table><hr></div><div class="sect1" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="macro-tips-input"></a>Getting Input for a Macro</h2></div></div><div></div></div><p>
    2. 

  2.     The dialog-based macro discussed in <a href="dialog-macro.html" title="Chapter 14. A Dialog-Based Macro">Chapter 14, <i>A Dialog-Based Macro</i></a>
    3. 

  3.     reflects a conventional approach to obtaining input in a Java program.
    4. 

  4.     Nevertheless, it can be too lengthy or tedious for someone
    5. 

  5.     trying to write a macro quickly. Not every macro needs a user interface
    6. 

  6.     specified in such detail; some macros require only a single keystroke or
    7. 

  7.     no input at all. In this section we outline some other techniques for
    8. 

  8.     obtaining input that will help you write macros quickly.
    9. 

  9.   </p><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="macro-tips-input-single-line"></a>Getting a Single Line of Text</h3></div></div><div></div></div><p>
    10. 

  10.     As mentioned earlier in <a href="helpful-methods.html" title="Helpful Methods in the
    11. 

  11.   Macros Class">the section called &#8220;Helpful Methods in the
    12. 

  12.   Macros Class&#8221;</a>, the method
    13. 

  13.     <tt class="function">Macros.input()</tt> offers a convenient way to obtain
    14. 

  14.     a single line of text input. Here is an example that inserts a pair
    15. 

  15.     of HTML markup tags specified by the user.
    16. 

  16.   </p><div class="informalexample"><table border="0" bgcolor="#E0E0E0"><tr><td><pre class="programlisting">// Insert_Tag.bsh
    17. 

  17. 

  18. void insertTag()
    19. 

  19. {
    20. 

  20.     caret = textArea.getCaretPosition();
    21. 

  21.     tag = Macros.input(view, &#8220;<span class="quote">Enter name of tag:</span>&#8221;);
    22. 

  22.     if( tag == null || tag.length() == 0) return;
    23. 

  23.     text = textArea.getSelectedText();
    24. 

  24.     if(text == null) text = &#8220;<span class="quote"></span>&#8221;;
    25. 

  25.     sb = new StringBuffer();
    26. 

  26.     sb.append(&#8220;<span class="quote">&lt;</span>&#8221;).append(tag).append(&#8220;<span class="quote">&gt;</span>&#8221;);
    27. 

  27.     sb.append(text);
    28. 

  28.     sb.append(&#8220;<span class="quote">&lt;/</span>&#8221;).append(tag).append(&#8220;<span class="quote">&gt;</span>&#8221;);
    29. 

  29.     textArea.setSelectedText(sb.toString());
    30. 

  30.     if(text.length() == 0)
    31. 

  31.         textArea.setCaretPosition(caret + tag.length() + 2);
    32. 

  32. }
    33. 

  33. 

  34. insertTag();
    35. 

  35. 

  36. // end Insert_Tag.bsh</pre></td></tr></table></div><p>
    37. 

  37.     Here the call to <tt class="function">Macros.input()</tt> seeks the name
    38. 

  38.     of the markup tag. This method sets the message box title to a fixed string,
    39. 

  39.     &#8220;<span class="quote">Macro input</span>&#8221;, but the specific message <span><b class="guilabel">Enter name
    40. 

  40.     of tag</b></span> provides all the information necessary. The return value
    41. 

  41.     <tt class="varname">tag</tt> must be tested to see if it is null.  This would
    42. 

  42.     occur if the user presses the <span><b class="guilabel">Cancel</b></span> button or
    43. 

  43.     closes the dialog window displayed by <tt class="function">Macros.input()</tt>.
    44. 

  44.   </p></div><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="macro-tips-input-multiple-data"></a>Getting Multiple Data Items</h3></div></div><div></div></div><p>
    45. 

  45.     If more than one item of input is needed, a succession of calls to
    46. 

  46.     <tt class="function">Macros.input()</tt> is a possible, but awkward approach,
    47. 

  47.     because it would not be possible to correct early input after the
    48. 

  48.     corresponding message box is dismissed.  Where more is required,
    49. 

  49.     but a full dialog layout is either unnecessary or too much work,
    50. 

  50.     the Java method <tt class="function">JOptionPane.showConfirmDialog()</tt>
    51. 

  51.     is available. The version to use has the following prototype:
    52. 

  52.   </p><div class="itemizedlist"><ul type="disc"><li><div class="funcsynopsis"><table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0"><tr><td><code class="funcdef">public static int <b class="fsfunc">showConfirmDialog</b>(</code></td><td>Component  </td><td><var class="pdparam">parentComponent</var>, </td></tr><tr><td> </td><td>Object  </td><td><var class="pdparam">message</var>, </td></tr><tr><td> </td><td>String  </td><td><var class="pdparam">title</var>, </td></tr><tr><td> </td><td>int  </td><td><var class="pdparam">optionType</var>, </td></tr><tr><td> </td><td>int  </td><td><var class="pdparam">messageType</var><code>)</code>;</td></tr></table></div></li></ul></div><p>
    53. 

  53.     The usefulness of this method arises from the fact that the
    54. 

  54.     <tt class="varname">message</tt> parameter can be an object of any
    55. 

  55.     Java class (since all classes are derived from
    56. 

  56.     <tt class="classname">Object</tt>), or any array of objects.  The
    57. 

  57.     following example shows how this feature can be used.
    58. 

  58.   </p><div class="informalexample"><table border="0" bgcolor="#E0E0E0"><tr><td><pre class="programlisting">// excerpt from Write_File_Header.bsh
    59. 

  59. 

  60. title = &#8220;<span class="quote">Write file header</span>&#8221;;
    61. 

  61. 

  62. currentName = buffer.getName();
    63. 

  63. 

  64. nameField = new JTextField(currentName);
    65. 

  65. authorField = new JTextField(&#8220;<span class="quote">Your name here</span>&#8221;);
    66. 

  66. descField = new JTextField(&#8220;<span class="quote"></span>&#8221;, 25);
    67. 

  67. 

  68. namePanel = new JPanel(new GridLayout(1, 2));
    69. 

  69. nameLabel = new JLabel(&#8220;<span class="quote">Name of file:</span>&#8221;, SwingConstants.LEFT);
    70. 

  70. saveField = new JCheckBox(&#8220;<span class="quote">Save file when done</span>&#8221;,
    71. 

  71.     !buffer.isNewFile());
    72. 

  72. namePanel.add(nameLabel);
    73. 

  73. namePanel.add(saveField);
    74. 

  74. 

  75. 

  76. message = new Object[9];
    77. 

  77. message[0] = namePanel;
    78. 

  78. message[1] = nameField;
    79. 

  79. message[2] = Box.createVerticalStrut(10);
    80. 

  80. message[3] = &#8220;<span class="quote">Author's name:</span>&#8221;;
    81. 

  81. message[4] = authorField;
    82. 

  82. message[5] = Box.createVerticalStrut(10);
    83. 

  83. message[6] = &#8220;<span class="quote">Enter description:</span>&#8221;;
    84. 

  84. message[7] = descField;
    85. 

  85. message[8] = Box.createVerticalStrut(5);
    86. 

  86. 

  87. if( JOptionPane.OK_OPTION !=
    88. 

  88.     JOptionPane.showConfirmDialog(view, message, title,
    89. 

  89.         JOptionPane.OK_CANCEL_OPTION,
    90. 

  90.         JOptionPane.QUESTION_MESSAGE))
    91. 

  91.     return null;
    92. 

  92. 

  93. // *****remainder of macro script omitted*****
    94. 

  94. 

  95. // end excerpt from Write_File_Header.bsh</pre></td></tr></table></div><p>
    96. 

  96.     This macro takes several items of user input and produces a formatted
    97. 

  97.     file header at the beginning of the buffer. The full macro is included in
    98. 

  98.     the set of macros installed by jEdit. There are a number of input
    99. 

  99.     features of this excerpt worth noting.
    100. 

  100.   </p><div class="itemizedlist"><ul type="disc"><li><p>
    101. 

  101.         The macro uses a total of seven visible components. Two of them are
    102. 

  102.         created behind the scenes by <tt class="function">showConfirmDialog()</tt>,
    103. 

  103.         the rest are made by the macro. To arrange them, the script creates an
    104. 

  104.         array of <tt class="classname">Object</tt> objects and assigns components to
    105. 

  105.         each location in the array. This translates to a fixed, top-to-bottom
    106. 

  106.         arrangement in the message box created by
    107. 

  107.         <tt class="function">showConfirmDialog()</tt>.
    108. 

  108.       </p></li><li><p>
    109. 

  109.         The macro uses <tt class="classname">JTextField</tt> objects to
    110. 

  110.         obtain most of the input data.  The fields <tt class="varname">nameField</tt>
    111. 

  111.         and <tt class="varname">authorField</tt> are created with constructors
    112. 

  112.         that take the initial, default text to be displayed in the field as a
    113. 

  113.         parameter.  When the message box is displayed, the default text
    114. 

  114.         will appear and can be altered or deleted by the user.
    115. 

  115.       </p></li><li><p>
    116. 

  116.         The text field <tt class="varname">descField</tt> uses an empty string for its
    117. 

  117.         initial value. The second parameter in its constructor sets the width of
    118. 

  118.         the text field component, expressed as the number of characters of
    119. 

  119.         &#8220;<span class="quote">average</span>&#8221; width. When
    120. 

  120.         <tt class="function">showConfirmDialog()</tt> prepares the layout of the
    121. 

  121.         message box, it sets the width wide enough to accommodate the
    122. 

  122.         designated with of <tt class="varname">descField</tt>. This technique produces
    123. 

  123.         a message box and input text fields that are wide enough for your data
    124. 

  124.         with one line of code.
    125. 

  125.       </p></li><li><p>
    126. 

  126.         The displayed message box includes a <tt class="classname">JCheckBox</tt>
    127. 

  127.         component that determines whether the buffer will be saved to disk
    128. 

  128.         immediately after the file header is written. To conserve space
    129. 

  129.         in the message box, we want to display the check box to the
    130. 

  130.         right of the label <span><b class="guilabel">Name of file:</b></span>. To do that,
    131. 

  131.         we create a <tt class="classname">JPanel</tt> object and populate it with
    132. 

  132.         the label and the checkbox in a left-to-right
    133. 

  133.         <tt class="classname">GridLayout</tt>.  The <tt class="classname">JPanel</tt>
    134. 

  134.         containing the two components is then added to the beginning of
    135. 

  135.         <tt class="varname">message</tt> array.
    136. 

  136.       </p></li><li><p>
    137. 

  137.         The two visible components created by
    138. 

  138.         <tt class="function">showConfirmDialog()</tt> appear at positions 3 and 6 of
    139. 

  139.         the <tt class="varname">message</tt> array. Only the text is required; they
    140. 

  140.         are rendered as text labels.
    141. 

  141.       </p></li><li><p>
    142. 

  142.         There are three invisible components created by
    143. 

  143.         <tt class="function">showConfirmDialog()</tt>.  Each of them involves
    144. 

  144.         a call to <tt class="function">Box.createVerticalStrut()</tt>.  The
    145. 

  145.         <tt class="classname">Box</tt> class is a sophisticated layout class
    146. 

  146.         that gives the user great flexibility in sizing and positioning
    147. 

  147.         components. Here we use a <tt class="function">static</tt> method of
    148. 

  148.         the <tt class="classname">Box</tt> class that produces a vertical
    149. 

  149.         <i class="glossterm">strut</i>.  This is a transparent component
    150. 

  150.         whose width expands to fill its parent component (in this case,
    151. 

  151.         the message box).  The single parameter indicates the height
    152. 

  152.         of the strut in pixels.  The last call to
    153. 

  153.         <tt class="function">createVerticalStrut()</tt> separates the
    154. 

  154.         description text field from the <span><b class="guilabel">OK</b></span> and
    155. 

  155.         <span><b class="guilabel">Cancel</b></span> buttons that are automatically added
    156. 

  156.         by <tt class="function">showConfirmDialog()</tt>.
    157. 

  157.       </p></li><li><p>
    158. 

  158.         Finally, the call to <tt class="function">showConfirmDialog()</tt> uses
    159. 

  159.         defined constants for the option type and the message type.  The
    160. 

  160.         constants are the same as those used with the
    161. 

  161.         <tt class="function">Macros.confirm()</tt> method; see
    162. 

  162.         <a href="helpful-methods.html" title="Helpful Methods in the
    163. 

  163.   Macros Class">the section called &#8220;Helpful Methods in the
    164. 

  164.   Macros Class&#8221;</a>. The
    165. 

  165.         option type signifies the use of <span><b class="guilabel">OK</b></span>
    166. 

  166.         and <span><b class="guilabel">Cancel</b></span> buttons. The
    167. 

  167.         <tt class="constant">QUERY_MESSAGE</tt> message type causes the message box
    168. 

  168.         to display a question mark icon.
    169. 

  169.       </p><p>
    170. 

  170.         The return value of the method
    171. 

  171.         is tested against the value <tt class="constant">OK_OPTION</tt>.  If
    172. 

  172.         the return value is something else (because the
    173. 

  173.         <span><b class="guilabel">Cancel</b></span> button was pressed or because the
    174. 

  174.         message box window was closed without a button press), a
    175. 

  175.         <tt class="constant">null</tt> value is returned to a calling function,
    176. 

  176.         signaling that the user canceled macro execution.  If the return
    177. 

  177.         value is <tt class="constant">OK_OPTION</tt>, each of the input components
    178. 

  178.         can yield their contents for further processing by calls to
    179. 

  179.         <tt class="function">JTextField.getText()</tt> (or, in the case of
    180. 

  180.         the check box, <tt class="function">JCheckBox.isSelected()</tt>).
    181. 

  181.       </p></li></ul></div></div><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="tips-macro-input-combo"></a>Selecting Input From a List</h3></div></div><div></div></div><p>
    182. 

  182.   Another useful way to get user input for a macro is to use a combo box
    183. 

  183.   containing a number of pre-set options. If this is the only input
    184. 

  184.   required, one of the versions of <tt class="function">showInputDialog()</tt>
    185. 

  185.   in the <tt class="classname">JOptionPane</tt> class provides a shortcut.
    186. 

  186.   Here is its prototype:
    187. 

  187. </p><div class="itemizedlist"><ul type="disc"><li><div class="funcsynopsis"><table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0"><tr><td><code class="funcdef">public static Object <b class="fsfunc">showInputDialog</b>(</code></td><td>Component  </td><td><var class="pdparam">parentComponent</var>, </td></tr><tr><td> </td><td>Object  </td><td><var class="pdparam">message</var>, </td></tr><tr><td> </td><td>String  </td><td><var class="pdparam">title</var>, </td></tr><tr><td> </td><td>int  </td><td><var class="pdparam">messageType</var>, </td></tr><tr><td> </td><td>Icon  </td><td><var class="pdparam">icon</var>, </td></tr><tr><td> </td><td>Object[]  </td><td><var class="pdparam">selectionValues</var>, </td></tr><tr><td> </td><td>Object  </td><td><var class="pdparam">initialSelectionValue</var><code>)</code>;</td></tr></table></div></li></ul></div><p>
    188. 

  188.     This method creates a message box containing a drop-down list of the
    189. 

  189.     options specified in the method's parameters, along with
    190. 

  190.     <span><b class="guilabel">OK</b></span> and <span><b class="guilabel">Cancel</b></span> buttons.
    191. 

  191.     Compared to <tt class="function">showConfirmDialog()</tt>, this method lacks
    192. 

  192.     an <tt class="varname">optionType</tt> parameter and has three additional
    193. 

  193.     parameters: an <tt class="varname">icon</tt> to display in the dialog
    194. 

  194.     (which can be set to <tt class="constant">null</tt>), an array of
    195. 

  195.     <tt class="varname">selectionValues</tt> objects, and a reference to one
    196. 

  196.     of the options as the <tt class="varname">initialSelectionValue</tt> to be
    197. 

  197.     displayed. In addition, instead of returning an <tt class="classname">int</tt>
    198. 

  198.     representing the user's action, <tt class="function">showInputDialog()</tt>
    199. 

  199.     returns the <tt class="classname">Object</tt> corresponding to the user's
    200. 

  200.     selection, or <tt class="constant">null</tt> if the selection is canceled.
    201. 

  201.   </p><p>
    202. 

  202.     The following macro fragment illustrates the use of this method.
    203. 

  203.   </p><div class="informalexample"><table border="0" bgcolor="#E0E0E0"><tr><td><pre class="programlisting">// fragment illustrating use of showInputDialog()
    204. 

  204. options = new Object[5];
    205. 

  205. options[0] = "JLabel";
    206. 

  206. options[1] = "JTextField";
    207. 

  207. options[2] = "JCheckBox";
    208. 

  208. options[3] = "HistoryTextField";
    209. 

  209. options[4} = "-- other --";
    210. 

  210. 

  211. result = JOptionPane.showInputDialog(view,
    212. 

  212.     "Choose component class",
    213. 

  213.     "Select class for input component",
    214. 

  214.     JOptionPane.QUESTION_MESSAGE,
    215. 

  215.     null, options, options[0]);</pre></td></tr></table></div><p>
    216. 

  216.     The return value <tt class="varname">result</tt> will contain either the
    217. 

  217.     <tt class="classname">String</tt> object representing the selected text
    218. 

  218.     item or <tt class="constant">null</tt> representing no selection.  Any
    219. 

  219.     further use of this fragment would have to test the value of
    220. 

  220.     <tt class="varname">result</tt> and likely exit from the macro if the value
    221. 

  221.     equaled <tt class="constant">null</tt>.
    222. 

  222.   </p><p>
    223. 

  223.     A set of options can be similarly placed in a
    224. 

  224.     <tt class="classname">JComboBox</tt> component created as part of a larger
    225. 

  225.     dialog or <tt class="function">showMessageDialog()</tt> layout.  Here are some
    226. 

  226.     code fragments showing this approach:
    227. 

  227.   </p><div class="informalexample"><table border="0" bgcolor="#E0E0E0"><tr><td><pre class="programlisting">// fragments from Display_Abbreviations.bsh
    228. 

  228. // import statements and other code omitted
    229. 

  229. 

  230. // from main routine, this method call returns an array
    231. 

  231. // of Strings representing the names of abbreviation sets
    232. 

  232. 

  233. abbrevSets = getActiveSets();
    234. 

  234. 

  235. ...
    236. 

  236. 

  237. // from showAbbrevs() method
    238. 

  238. 

  239. combo = new JComboBox(abbrevSets);
    240. 

  240. // set width to uniform size regardless of combobox contents
    241. 

  241. Dimension dim = combo.getPreferredSize();
    242. 

  242. dim.width = Math.max(dim.width, 120);
    243. 

  243. combo.setPreferredSize(dim);
    244. 

  244. combo.setSelectedItem(STARTING_SET); // defined as "global"
    245. 

  245. 

  246. // end fragments</pre></td></tr></table></div></div><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="macro-tips-single-char"></a>Using a Single Keypress as Input</h3></div></div><div></div></div><p>
    247. 

  247.     Some macros may choose to emulate the style of character-based text
    248. 

  248.     editors such as <span class="application">emacs</span> or
    249. 

  249.     <span class="application">vi</span>. They will require only a single keypress
    250. 

  250.     as input that would be handled by the macro but not displayed on the
    251. 

  251.     screen. If the keypress corresponds to a character value, jEdit can pass
    252. 

  252.     that value as a parameter to a BeanShell script.
    253. 

  253.   </p><p>
    254. 

  254.     The jEdit class <a href="../api/org/gjt/sp/jedit/gui/InputHandler.html" target="_top">InputHandler</a> is an abstract class
    255. 

  255.     that that manages associations between keyboard input and editing
    256. 

  256.     actions, along with the recording of macros. Keyboard input
    257. 

  257.     in jEdit is normally managed by the derived class
    258. 

  258.     <a href="../api/org/gjt/sp/jedit/gui/DefaultInputHandler.html" target="_top">DefaultInputHandler</a>. One of the methods in
    259. 

  259.     the <a href="../api/org/gjt/sp/jedit/gui/InputHandler.html" target="_top">InputHandler</a> class handles input from a
    260. 

  260.     single keypress:
    261. 

  261.   </p><div class="itemizedlist"><ul type="disc"><li><div class="funcsynopsis"><table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0"><tr><td><code class="funcdef">public void <b class="fsfunc">readNextChar</b>(</code></td><td>String  </td><td><var class="pdparam">prompt</var>, </td></tr><tr><td> </td><td>String  </td><td><var class="pdparam">code</var><code>)</code>;</td></tr></table></div></li></ul></div><p>
    262. 

  262.     When this method is called, the contents of the <tt class="varname">prompt</tt>
    263. 

  263.     parameter is shown in the view's status
    264. 

  264.     bar. The method then waits for a key press, after which
    265. 

  265.     the contents of the <tt class="varname">code</tt> parameter will be run as
    266. 

  266.     a BeanShell script, with one important modification. Each time the
    267. 

  267.     string <tt class="varname">__char__</tt> appears in the parameter script, it
    268. 

  268.     will be substituted by the character pressed. The key press
    269. 

  269.     is &#8220;<span class="quote">consumed</span>&#8221; by <tt class="function">readNextChar()</tt>.
    270. 

  270.     It will not be displayed on the screen or otherwise processed by jEdit.
    271. 

  271.   </p><p>
    272. 

  272.     Using <tt class="function">readNextChar()</tt> requires a macro within the
    273. 

  273.     macro, formatted as a single, potentially lengthy string literal. The
    274. 

  274.     following macro illustrates this technique. It selects a line of text
    275. 

  275.     from the current caret position to the first occurrence of the character
    276. 

  276.     next typed by the user. If the character does not appear on the line, no
    277. 

  277.     new selection occurs and the display remains unchanged.
    278. 

  278.   </p><div class="informalexample"><table border="0" bgcolor="#E0E0E0"><tr><td><pre class="programlisting">// Next_Char.bsh
    279. 

  279. 

  280. script = new StringBuffer(512);
    281. 

  281. script.append( "start = textArea.getCaretPosition();"         );
    282. 

  282. script.append( "line = textArea.getCaretLine();"              );
    283. 

  283. script.append( "end = textArea.getLineEndOffset(line) + 1;"   );
    284. 

  284. script.append( "text = buffer.getText(start, end - start);"   );
    285. 

  285. script.append( "match = text.indexOf(__char__, 1);"           );
    286. 

  286. script.append( "if(match != -1) {"                            );
    287. 

  287. script.append(   "if(__char__ != '\\n') ++match;"             );
    288. 

  288. script.append(   "textArea.select(start, start + match - 1);" );
    289. 

  289. script.append( "}"                                            );
    290. 

  290. 

  291. view.getInputHandler().readNextChar("Enter a character",
    292. 

  292.     script.toString());
    293. 

  293. 

  294. // end Next_Char.bsh</pre></td></tr></table></div><p>
    295. 

  295.     Once again, here are a few comments on the macro's design.
    296. 

  296.   </p><div class="itemizedlist"><ul type="disc"><li><p>
    297. 

  297.         A <tt class="classname">StringBuffer</tt> object is used for efficiency; it
    298. 

  298.         obviates multiple creation of fixed-length <tt class="classname">String</tt>
    299. 

  299.         objects. The parameter to the constructor of <tt class="varname">script</tt>
    300. 

  300.         specifies the initial size of the buffer that will receive the contents
    301. 

  301.         of the child script.
    302. 

  302.       </p></li><li><p>
    303. 

  303.         Besides the quoting of the script code, the formatting of the macro is
    304. 

  304.         entirely optional but (hopefully) makes it easier to read.
    305. 

  305.       </p></li><li><p>
    306. 

  306.         It is important that the child script be self-contained.  It does
    307. 

  307.         not run in the same namespace as the &#8220;<span class="quote">parent</span>&#8221; macro
    308. 

  308.         <tt class="filename">Next_Char.bsh</tt> and therefore does not share
    309. 

  309.         variables, methods, or scripted objects defined in the parent
    310. 

  310.         macro.
    311. 

  311.       </p></li><li><p>
    312. 

  312.         Finally, access to the <a href="../api/org/gjt/sp/jedit/gui/InputHandler.html" target="_top">InputHandler</a> object used
    313. 

  313.         by jEdit is available by calling
    314. 

  314.         <tt class="function">getInputHandler()</tt> on the current view.
    315. 

  315.       </p></li></ul></div></div></div><div class="navfooter"><hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="macro-tips.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="macro-tips.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="startup-scripts.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">Chapter 15. Macro Tips and Techniques </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> Startup Scripts</td></tr></table></div></body></html>
    316. 

  316.