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<!-- $XConsortium: ch04.sgm /main/8 1996/09/08 19:39:21 rws $ -->
<!-- (c) Copyright 1995 Digital Equipment Corporation. -->
<!-- (c) Copyright 1995 Hewlett-Packard Company. -->
<!-- (c) Copyright 1995 International Business Machines Corp. -->
<!-- (c) Copyright 1995 Sun Microsystems, Inc. -->
<!-- (c) Copyright 1995 Novell, Inc. -->
<!-- (c) Copyright 1995 FUJITSU LIMITED. -->
<!-- (c) Copyright 1995 Hitachi. -->
<chapter id="IPG.motif.div.1">
<title id="IPG.motif.mkr.1">Xt, Xlib, and Motif Dependencies</title>
<para>For information on Xt and Xlib dependencies, refer to Chapter 13 of <citetitle>Xlib &mdash; C Language Interface</citetitle>.</para>
<para>The rest of this chapter discusses tasks related to internationalizing
with Motif.</para>
<sect1 id="IPG.motif.div.2">
<title id="IPG.motif.mkr.2">Locale Management<indexterm><primary>language
environment</primary><secondary>description</secondary></indexterm><indexterm>
<primary>environment, language</primary></indexterm></title>
<para>The term <emphasis>language environment</emphasis> refers to the set
of localized data that the application needs to run correctly in the user-specified
locale. A language environment supplies the rules associated with a specific
language. In addition, the language environment consists of any externally
stored data, such as localized strings or text used by the application. For
example, the menu items displayed by an application might be stored in separate
files for each language supported by the application. This type of data can
be stored in resource files, User Interface Definition (UID) files, or message
catalogs (on XPG3-compliant systems).</para>
<para>A single language environment is established when an application runs.
The language environment in which an application operates is specified by
the application user, often either by setting an environment variable ( <systemitem>LANG</systemitem> or <systemitem>LC_*</systemitem> on POSIX-based systems)
or by setting the xnlLanguage resource. The application then sets the language
environment based on the user's specification. The application can do this
by using the <computeroutput>setlocale()</computeroutput> function in a language
procedure established by the <computeroutput>XtSetLanguageProc()</computeroutput>
function. This causes Xt to cache a per-display language string that is used
by the <computeroutput>XtResolvePathname()</computeroutput> function to find
resource, bitmap, and User Interface Language (UIL) files.</para>
<para>An application that supplies a language procedure can either provide
its own procedure or use an Xt<indexterm><primary>language procedure</primary>
</indexterm> default procedure. In either case, the application establishes
the language procedure by calling the <computeroutput>XtSetLanguageProc()</computeroutput> function before initializing the toolkit and before loading
the resource databases (such as by calling the <computeroutput>XtAppInitialize()</computeroutput> function). When a language procedure is installed, Xt calls
it in the process of constructing the initial resource database. Xt uses
the value returned by the language procedure as its per-display language
string.</para>
<para>The default language procedure performs the following tasks:</para>
<itemizedlist remap="Bullet1"><listitem><para>Sets the locale. This is done
by using:</para>
<programlisting>setlocale(LC_ALL, <symbol role="Variable">language</symbol>);</programlisting>
<para>where <symbol role="Variable">language</symbol> is the value of the <systemitem>xnlLanguage</systemitem> resource, or the empty string (&ldquo;&rdquo;) if
the <systemitem>xnlLanguage</systemitem> resource is not set. When the <systemitem>xnlLanguage</systemitem> resource is not set, the locale is generally derived
from an environment variable (<systemitem>LANG</systemitem> on POSIX-based
systems).</para>
</listitem><listitem><para>Calls the <computeroutput>XSupportsLocale()</computeroutput>
function to verify that the locale just set is supported. If not, a warning
message is issued and the locale is set to C.</para>
</listitem><listitem><para>Calls the <computeroutput>XSetLocaleModifiers()</computeroutput> function specifying the empty string.</para>
</listitem><listitem><para>Returns the value of the current locale. On ANSI
C-based systems, this is the result of calling:</para>
<programlisting>setlocale(LC_ALL, NULL);</programlisting>
</listitem></itemizedlist>
<para>The application can use the default language procedure by making the
call to the <computeroutput>XtSetLanguageProc()</computeroutput> function
in the following manner:</para>
<programlisting>XtSetLanguageProc(NULL, NULL, NULL);
...
toplevel = XtAppInitialize(...);</programlisting>
<para>By default, Xt does not install any language procedure. If the application
does not call the <computeroutput>XtSetLanguageProc()</computeroutput> function,
Xt uses as its per-display language string the value of the <systemitem>xnlLanguage</systemitem> resource if it is set. If the <systemitem>xnlLanguage</systemitem> resource is not set, Xt derives the language string from the <systemitem>LANG</systemitem> environment variable. <literal><indexterm><primary>XtSetLanguageProc</primary><secondary>default language</secondary></indexterm></literal></para>
<note>
<para>The per-display language string that results from this process is implementation-dependent,
and Xt provides no public means of examining the language string once it
is established.</para>
</note>
<para>By supplying its own language procedure, an application can use any
procedure it wants for setting the language string.</para>
</sect1>
<sect1 id="IPG.motif.div.3">
<title id="IPG.motif.mkr.3">Font Management</title>
<para>The desktop uses render tables to display text. A render table is a tagged
collection of renditions, each of which specifies the data used in rendering
compound strings. For information on renditions, and render tables, refer
to &MotifProgGd;.</para>
</sect1>
<sect1 id="IPG.motif.div.11">
<title id="IPG.motif.mkr.5">Drawing Localized Text<indexterm><primary>compound
strings</primary><secondary>for international text display</secondary></indexterm><indexterm>
<primary>compound strings</primary><secondary>structures, interaction with
render tables</secondary></indexterm></title>
<para>A compound string (type <classname>XmString</classname>)is a means of
encoding text so that it can be displayed in many different fonts without
changing anything in the program. A rendition, which is identified by a rendition
tag, specifies the font (and other characteristics, such as color) with which
the compound string with that rendition tag is to be rendered.</para>
<para>Especially useful for internationalization purposes are render tables,
which are collections of renditions. Among the renditions in the table may
be one tagged <systemitem class="constant">_MOTIF_DEFAULT_LOCALE</systemitem>,
which is the rendition used for the current locale. For internationalized
applications, render tables should be specified in resource files.</para>
<para>The foregoing discussion provides only a brief overview of some subjects
related to drawing localized text; for complete information, refer to &MotifProgGd;.
</para>
</sect1>
<sect1 id="IPG.motif.div.18">
<title id="IPG.motif.mkr.11">Inputting Localized Text<indexterm><primary>VendorShell widget class</primary><secondary>as input manager</secondary></indexterm><indexterm>
<primary>input method</primary><secondary>VendorShell widget class</secondary>
</indexterm><indexterm><primary>VendorShell widget class</primary><secondary>geometry management</secondary></indexterm></title>
<para>In the system environment, the <computeroutput>VendorShell</computeroutput>
widget class is enhanced to provide the interface to the input method. While
the VendorShell class controls only one child widget in its geometry management,
an extension has been added to the VendorShell class to enhance it for managing
all components necessary in the interface to an input method. These components
include the status area, preedit area, and the MainWindow area.<indexterm>
<primary>VendorShell widget class</primary><secondary>managing components</secondary><tertiary>status area</tertiary></indexterm><indexterm><primary>VendorShell widget class</primary><secondary>managing components</secondary>
<tertiary>preedit area</tertiary></indexterm><indexterm><primary>VendorShell
widget class</primary><secondary>managing components</secondary><tertiary>MainWindow area</tertiary></indexterm></para>
<para>When the input method requires a status area or a preedit area or both,
the <computeroutput>VendorShell</computeroutput> widget automatically instantiates
the status and preedit areas and manages their geometry layout. Any status
area or preedit area is managed by the <computeroutput>VendorShell</computeroutput> widget internally and is not accessible by the client. The widget
instantiated as the child of the <computeroutput>VendorShell</computeroutput>
widget is called the MainWindow area.<indexterm><primary>input method</primary>
<secondary>requirements</secondary></indexterm><indexterm><primary>international
text input</primary><secondary>input methods</secondary></indexterm><indexterm>
<primary>input method</primary><secondary>international text input</secondary>
</indexterm></para>
<para>The input method to be used by the <computeroutput>VendorShell</computeroutput>
widget is determined by the <systemitem>XmNinputMethod</systemitem> resource;
for example, <computeroutput>@im=alt</computeroutput>. The default value of
Null indicates to choose the default input method associated with the locale
at the time that VendorShell is created. As such, the user can affect which
input method is selected by either setting the locale, setting the <systemitem>XmNinputMethod</systemitem> resource, or setting both. The locale name is
concatenated with the <systemitem>XmNinputMethod</systemitem> resource to
determine the input method name. The locale name must not be specified in
this resource. The modifier name for the<systemitem>XmNinputMethod</systemitem>
resource needs to be in the form <computeroutput>@im=</computeroutput><symbol role="Variable">modifier</symbol>, where modifier is the string used to qualify
which input method is selected.<indexterm><primary>input method</primary>
<secondary>determining, XmNinputMethod resource</secondary></indexterm><indexterm>
<primary>XmNinputMethod resource, determining input method</primary></indexterm></para>
<para>The <computeroutput>VendorShell</computeroutput> widget can support
multiple widgets that can share the input method. Yet only one widget can
have the keyboard focus (for example, receive key press events and send them
to an input method) at any given time. To support multiple widgets (such
as <computeroutput>Text</computeroutput> widgets), the widgets need to be
descendants of the <computeroutput>VendorShell</computeroutput> widget.</para>
<note>
<para>The <computeroutput>VendorShell</computeroutput> widget class is a superclass
of the <computeroutput>TransientShell</computeroutput> and <computeroutput>TopLevelShell</computeroutput> widget classes. As such, an instantiation
of a <computeroutput>TopLevelShell</computeroutput> or a <computeroutput>DialogShell</computeroutput> is essentially an instantiation of a <computeroutput>VendorShell</computeroutput> widget class.</para>
</note>
<para>The <computeroutput>VendorShell</computeroutput> widget behaves as an
input manager only if one of its descendants is an <computeroutput>XmText[Field]</computeroutput> instance. As soon as an <computeroutput>XmText[Field]</computeroutput>
instance is created as a descendant of the <computeroutput>VendorShell</computeroutput>
widget, <computeroutput>VendorShell</computeroutput> creates the necessary
areas required by the particular input methods dictated by the current locale.
Even if an <computeroutput>XmText[Field]</computeroutput> instance is not
mapped but just created, VendorShell has the geometry management behavior
as described previously.</para>
<para>A <computeroutput>VendorShell</computeroutput> widget does the following:<indexterm>
<primary>international text input</primary><secondary>VendorShell widget operations</secondary></indexterm></para>
<itemizedlist remap="Bullet1"><listitem><para>Enables applications to process
multibyte character input and output that is supported by the locales installed
in the system.<indexterm><primary>VendorShell widget operations</primary>
<secondary>processing multibyte character I/O</secondary></indexterm></para>
</listitem><listitem><para>Manages an input method instance as defined in
the <computeroutput>XmIm</computeroutput> reference functions.</para>
</listitem><listitem><para>Supports preediting within a preedit area in either
OnTheSpot, OffTheSpot, OverTheSpot, Root, or None mode. Localized text can be entered
into any <computeroutput>Text</computeroutput> child widget in a multiple <computeroutput>Text</computeroutput> children widget tree by changing the focus.</para>
</listitem><listitem><para>Provides geometry management for descendant child
widgets.</para>
</listitem></itemizedlist>
<note>
<para>Input method interactions may also be customized by users through a
dialog box that is invoked from the Style Manager application. Refer to the <emphasis>CDE User's Guide</emphasis> for more information.</para>
</note>
<sect2 id="IPG.motif.div.19">
<title>Geometry Management<indexterm><primary>international text input</primary>
<secondary>geometry management</secondary></indexterm><indexterm><primary>geometry management</primary><secondary>international text input</secondary>
</indexterm></title>
<para>The <computeroutput>VendorShell</computeroutput> widget provides geometry
management and focus management for the input method's user interface components,
as necessary. If the locale warrants it (for example, if the locale is a
Japanese Extended UNIX Code (EUC) locale), the <computeroutput>VendorShell</computeroutput> widget automatically allocates and manages the geometry
of any required preedit area or status area or both.</para>
<para>Depending on the current preediting being done, an auxiliary area may
be required. If so, the <computeroutput>VendorShell</computeroutput> widget
also instantiates and manages the auxiliary area. Typically, the child of
the <computeroutput>VendorShell</computeroutput> widget is a container widget
(such as the <computeroutput>XmBulletinBoard</computeroutput> or <computeroutput>XmRowColumn</computeroutput> widgets) that can manage
multiple <computeroutput>Text</computeroutput> and <computeroutput>TextField</computeroutput> widgets, which allow multibyte character
input from the user. In this scenario, all <computeroutput>Text</computeroutput> widgets share the same input method.</para>
<note>
<para><indexterm><primary>geometry management</primary><secondary>XmBulletinBoard
widget</secondary></indexterm><indexterm><primary>geometry management</primary>
<secondary>XmRowColumn widget</secondary></indexterm><indexterm><primary>geometry management</primary><secondary>Text widget</secondary></indexterm><indexterm>
<primary>geometry management</primary><secondary>TextField widget</secondary>
</indexterm><indexterm><primary>international text input</primary><secondary>multibyte characters</secondary></indexterm><indexterm><primary>input method</primary><secondary>Text widget</secondary></indexterm><indexterm><primary>Text widgets, input method</primary></indexterm>The status, preedit, and auxiliary
areas are not accessible to the application programmer. For example, it is
not intended for the application programmer to access the window ID of the
status area. The user does not need to worry about the instantiation or management
of these components as they are managed as required by the <computeroutput>VendorShell</computeroutput> widget class.</para>
</note>
<para>The application programmer has some control over the behavior of the
input method user interface components through <systemitem>XmNpreeditType</systemitem> resources of the <computeroutput>VendorShell</computeroutput>
widget class.<indexterm><primary>geometry management</primary><secondary>application programmer controls</secondary></indexterm><indexterm><primary>application programmer, controlling input method components</primary></indexterm>
(The <literal>OffTheSpot</literal>, <literal>OnTheSpot</literal>, and <literal>OverTheSpot</literal> modes are described elsewhere in this manual).</para>
<para>Geometry management extends to all input method user interface components.
When the application program window (a <computeroutput>TopLevelShell</computeroutput>
widget) is resized, the input method user interface components are resized
accordingly, and the preedited strings in them are rearranged as required.
Of course, this assumes that the shell window has a resize policy of True.
</para>
<para>When the <computeroutput>VendorShell</computeroutput> widget is created,
if a specific input method requires a status area, preedit area, or both,
the size of the VendorShell considers the areas required by these components.
The extra areas required by the preedit and status areas are part of the <computeroutput>VendorShell</computeroutput> widget's area. They are also
managed by the <computeroutput>VendorShell</computeroutput> widget, if resizing
is necessary.</para>
<para>Because of the potential instantiation of these areas (status and preedit),
depending on the input method currently being used, the size of the <computeroutput>VendorShell</computeroutput> widget area does not necessarily grow or shrink
to accommodate exactly the size of its child. The size of the <computeroutput>VendorShell</computeroutput> widget area grows or shrinks to accommodate
both its child's geometry <emphasis>and</emphasis> the geometry of these
input method user interface areas. There may be a difference (for example,
of 20 pixels) in height between the <computeroutput>VendorShell</computeroutput>
widget and its child widget (the MainWindow area). The width geometry is <symbol role="Variable">not</symbol> affected by the input method user interface
components.<indexterm><primary>VendorShell widget class</primary><secondary>size</secondary></indexterm><indexterm><primary>VendorShell widget class</primary><secondary>child widget size</secondary></indexterm></para>
<para>In summary, the requested size of the child is honored if possible;
the actual size of the <computeroutput>VendorShell</computeroutput> may be
larger than its child.</para>
<para>The requests to specify the geometry of the <computeroutput>VendorShell</computeroutput> widget and its child are honored as long as they do not
conflict with each other or are within the constraint of the <computeroutput>VendorShell</computeroutput> widget's ability to resize. When they do conflict,
the child's widget geometry request has higher precedence. For example, if
the size of the child widget is specified as 100x100, the size of VendorShell
is also specified as 100x100. The resulting VendorShell has a size of 100x120,
while its child widget gets a size of 100x100. If the size of the child widget
is not specified, the VendorShell shrinks its child widget if necessary to
honor its own size specification. For example, if the size of VendorShell
is specified as 100x100 and no size is specified for its child, the child
widget has a size of 100x80. If the <computeroutput>VendorShell</computeroutput> widget is disabled from resizing, regardless of what the geometry
request of its child is, the <computeroutput>VendorShell</computeroutput>
widget honors only its own geometry specification.</para>
</sect2>
<sect2 id="IPG.motif.div.20">
<title>Focus Management<indexterm><primary>international text input</primary>
<secondary>focus management</secondary></indexterm><indexterm><primary>VendorShell
widget class</primary><secondary>focus management</secondary></indexterm><indexterm>
<primary>focus management</primary><secondary>international text input</secondary>
</indexterm></title>
<para>Languages with large numbers of characters (such as Japanese and Chinese)
require an input method that allows the user to compose characters in that
language interactively.<indexterm><primary>input method</primary><secondary>multibyte characters</secondary></indexterm> This is because, for these languages,
there are many more characters than can be reasonably mapped to a terminal
keyboard.</para>
<para>The interactive process of composing characters in such languages is
called <emphasis>preediting</emphasis>. The preediting itself is handled
by the input method. However, the user interface of the preediting is determined
by the system environment. An interface needs to exist between the input
method and the system environment. This is done through the <computeroutput>VendorShell</computeroutput> widget of the system environment.<indexterm>
<primary>preediting</primary></indexterm><indexterm><primary>VendorShell
widget class</primary><secondary>as interface</secondary>
</indexterm><indexterm><primary>interfaces</primary><secondary>between input method and Common Desktop Environment</secondary>
</indexterm><indexterm><primary>input method</primary><secondary>Common Desktop
Environment interface</secondary></indexterm><indexterm><primary>Common Desktop
Environment</primary><secondary>input method interface</secondary></indexterm><indexterm>
<primary>preediting</primary></indexterm></para>
<para><!--Original XRef content: 'Figure&numsp;4&hyphen;3'--><xref role="CodeOrFigureOrTable"
linkend="IPG.motif.mkr.12"> illustrates a case with Japanese preediting. The
string shown in reverse video is the string in preediting. This string can
be moved across different windows by giving focus to the particular window.
However, only one preediting session can occur at one time.</para>
<figure>
<title id="IPG.motif.mkr.12">Japanese preediting example</title>
<graphic id="IPG.motif.grph.3" entityref="IPG.motif.fig.3"></graphic>
</figure>
<para>For an example of focus management, suppose a <computeroutput>TopLevelShell</computeroutput> widget (a subclass of the <computeroutput>VendorShell</computeroutput>
widget) has an <computeroutput>XmBulletinBoard</computeroutput> widget child
(MainWindow area), which has five <computeroutput>XmText</computeroutput>
widgets as children. Assume the locale requires the preedit area, and assume
the OverTheSpot mode is specified. Because the <computeroutput>VendorShell</computeroutput> widget manages only one instance of an input method, you
can run only one preedit area at a time inside the <computeroutput>TopLevelShell</computeroutput> widget. If the focus is moved from one <computeroutput>Text</computeroutput> widget to another, the current preedit string under
construction is also moved on top of the <computeroutput>Text</computeroutput>
widget that currently has focus. Processing of keys to the old <computeroutput>Text</computeroutput> widget is suspended temporarily. Subsequent interface
of the input method, such as the delivery of the string at preedit completion,
is made to the new, focused <computeroutput>Text</computeroutput> widget.<indexterm>
<primary>focus management</primary><secondary>example description</secondary>
</indexterm></para>
<para>The string being preedited can be moved to the location of the focus;
for example, by clicking the mouse.</para>
<para>A string that the end user is finished preediting and that is already
confirmed <emphasis>cannot</emphasis> be reconverted. Once the string is
composed, it is committed. Refer to Chapter 11 of &MotifProgGd; for information
on actions that cause a preedit string to be committed.</para>
</sect2>
</sect1>
<sect1 id="IPG.motif.div.21">
<title id="IPG.motif.mkr.13">Internationalized User Interface Language<indexterm>
<primary>National Language Support</primary><secondary>User Interface Language
(UIL)</secondary></indexterm><indexterm><primary>User Interface Language
(UIL), see UIL &lt;$nopage></primary>
</indexterm></title>
<para>The capability to parse a multibyte character string as a string literal
has been added to the User Interface Language (UIL).<indexterm><primary>programming for international use</primary><secondary>UIL</secondary><tertiary>parsing multibyte character string</tertiary></indexterm> Creation of a UIL
file is performed by using the characteristics of the target language and
writing the User Interface Definition (UID) file.</para>
<sect2 id="IPG.motif.div.22">
<title>Programming for Internationalized User Interface Language<indexterm>
<primary>locales</primary><secondary>UIL compiler</secondary></indexterm></title>
<para>The UIL compiler parses nonstandard charsets as locale text. This requires
the UIL compiler to be run in the same locale as any locale text.<indexterm>
<primary>programming for international use</primary><secondary>UIL</secondary>
<tertiary>parsing nonstandard charsets</tertiary></indexterm><indexterm>
<primary>programming for international use</primary><secondary>UIL</secondary>
<tertiary>locale text</tertiary></indexterm></para>
<para>If the locale text of a widget requires a font set (more than one font),
the fonts must be specified within the resource file as a render table.</para>
<para>To use a specific language with UIL, a UIL file is written according
to characteristics of the target language and compiled into a UID file. The
UIL file that contains localized text needs to be compiled in the locale
in which it is to run.</para>
<sect3 id="IPG.motif.div.23">
<title>String Literals<indexterm><primary>programming for international use</primary><secondary>UIL</secondary><tertiary>string literals</tertiary></indexterm><indexterm>
<primary>string literals</primary><secondary>programming for international
UIL</secondary></indexterm></title>
<para>The following shows examples of literal strings. The cur_charset value
is always set to the default_charset value, which allows the string literal
to contain locale text.</para>
<para>To set locale text in the string literal with the default_charset value,
enter the following:</para>
<programlisting>XmNlabelString = '<symbol>XXXXXX</symbol>';</programlisting>
<para>OR</para>
<programlisting>XmNlabelString = #default_charset&ldquo;<symbol>XXXXXX</symbol>&rdquo;;
</programlisting>
<para>Compile the UIL file with the <systemitem>LANG</systemitem> environment
variable matching the encoding of the locale text. Otherwise, the string
literal is not compiled properly.</para>
</sect3>
<sect3 id="IPG.motif.div.24">
<title>Font<indexterm><primary>font sets</primary><secondary>programming
for international UIL</secondary></indexterm> Sets<indexterm><primary>programming
for international use</primary><secondary>UIL</secondary></indexterm><indexterm>
<primary>programming for international UIL</primary></indexterm><indexterm>
<primary>font sets</primary><secondary>programming for international UIL</secondary>
</indexterm></title>
<para>The font set cannot be set through UIL source programming. Whenever
the font set is required, you must set it in the resource file as render
table resource. Refer to &MotifProgGd; for more information.</para>
</sect3>
<sect3 id="IPG.motif.div.25">
<title>Font Lists<indexterm><primary>font lists in UIL, specifying resources
for</primary></indexterm></title>
<para>Like font sets, font lists are specified in resource files as render
tables. Refer to &MotifProgGd; for detailed information.</para>
</sect3>
<sect3 id="IPG.motif.div.25a">
<title>Render Tables<indexterm><primary>render tables in UIL, specifying resources
for</primary></indexterm></title>
<para>Render tables, as well as renditions, tab lists,
and tab stops, are implemented as a special class of objects.
Refer to &MotifProgGd; for detailed information.</para>
</sect3>
<sect3 id="IPG.motif.div.26">
<title>Creating<indexterm><primary>resource files</primary><secondary>creating
for international UIL</secondary></indexterm> Resource Files<indexterm><primary>programming for international use</primary><secondary>UIL</secondary></indexterm><indexterm>
<primary>programming for international UIL</primary></indexterm><indexterm>
<primary>resource files, creating</primary></indexterm><indexterm><primary>resource files</primary><secondary>creating for international UIL</secondary>
</indexterm></title>
<para>If necessary, set the input method-related resources in the resource
file as shown in the following example:</para>
<programlisting>*preeditType: OverTheSpot, OnTheSpot, OffTheSpot, Root, or None
</programlisting>
</sect3>
<sect3 id="IPG.motif.div.27">
<title>Setting the<indexterm><primary>setting the environment</primary><secondary>for international UIL</secondary></indexterm> Environment<indexterm><primary>programming for international use</primary><secondary>UIL</secondary></indexterm><indexterm>
<primary>programming for international UIL</primary></indexterm><indexterm>
<primary>setting the environment</primary><secondary>for international UIL</secondary></indexterm></title>
<para>For a locale-sensitive application, set the UID file to the appropriate
directory. Set the <systemitem>UIDPATH</systemitem> or <systemitem>XAPPLRESDIR</systemitem> environment variable to the appropriate value.</para>
<para>For example, to run the <computeroutput>uil_sample</computeroutput>
program with an English environment (<systemitem>LANG</systemitem> environment
variable is <computeroutput>en_US</computeroutput>), set <filename>uil_sample.uid</filename> with Latin characters at the <filename>$HOME/en_US</filename>
directory, or set <filename>uil_sample.uid</filename> to a directory and
set the <systemitem>UIDPATH</systemitem> environment variable to the full
path name of the <filename>uil_sample.uid</filename> file.</para>
<para>To run the <computeroutput>uil_sample</computeroutput> program with
a Japanese environment (<systemitem>LANG</systemitem> environment variable
is <systemitem>ja_JP</systemitem>), create a <filename>uil_sample.uid</filename>
file with Japanese (multibyte) characters at the <filename>$HOME/ja_JP</filename>
directory, or place <filename>uil_sample.uid</filename> to a unique directory
and set the <systemitem>UIDPATH</systemitem> environment variable to the
full path name of the <filename>uil_sample.uid</filename> file. The following
list specifies the possible variables:</para>
<informaltable>
<tgroup cols="2" colsep="0" rowsep="0">
<colspec align="left" colwidth="100*">
<colspec align="left" colwidth="356*">
<tbody>
<row>
<entry><para><emphasis>%U</emphasis></para></entry>
<entry><para>Specifies the UID file string.</para></entry></row>
<row>
<entry><para><emphasis>%N</emphasis></para></entry>
<entry><para>Specifies the class name of the application.</para></entry></row>
<row>
<entry><para><emphasis>%L</emphasis></para></entry>
<entry><para>Specifies the value of the <computeroutput>xnlLanguage</computeroutput>
resource or <filename>LC_CTYPE</filename> category.</para></entry></row>
<row>
<entry><para><emphasis>%l</emphasis></para></entry>
<entry><para>Specifies the language component of the <computeroutput>xnlLanguage</computeroutput> resource or the <computeroutput>LC_CTYPE</computeroutput>
category.</para></entry></row></tbody></tgroup></informaltable>
<para>If the <systemitem>XAPPLRESDIR</systemitem> environment variable is
set, the <computeroutput>MrmOpenHierarchy()</computeroutput> function searches
the UID file in the following order:<indexterm><primary>setting the environment</primary><secondary>searching the UID file</secondary></indexterm><indexterm>
<primary>UID file search</primary></indexterm><indexterm><primary>MrmOpenHierarchy
function, searching UID file</primary></indexterm><indexterm><primary>UID
file search</primary></indexterm></para>
<orderedlist><listitem><para>UID file path name</para>
</listitem><listitem><para><computeroutput>$UIDPATH</computeroutput></para>
</listitem><listitem><para>%U</para>
</listitem><listitem><para><computeroutput>$XAPPLRESDIR/</computeroutput> <emphasis>%L</emphasis><computeroutput>/uid/</computeroutput><emphasis>%N</emphasis> <computeroutput>/</computeroutput><emphasis>%U</emphasis></para>
</listitem><listitem><para><computeroutput>$XAPPLRESDIR/</computeroutput> <emphasis>%l</emphasis><computeroutput>/uid/</computeroutput><emphasis>%N</emphasis> <computeroutput>/</computeroutput><emphasis>%U</emphasis></para>
</listitem><listitem><para><computeroutput>$XAPPLRESDIR/uid/</computeroutput> <emphasis>%N</emphasis><computeroutput>/</computeroutput><emphasis>%U</emphasis></para>
</listitem><listitem><para><computeroutput>$XAPPLRESDIR/</computeroutput> <emphasis>%L</emphasis><computeroutput>/uid/</computeroutput><emphasis>%U</emphasis></para>
</listitem><listitem><para><computeroutput>$XAPPLRESDIR/</computeroutput> <emphasis>%l</emphasis><computeroutput>/uid/</computeroutput><emphasis>%U</emphasis></para>
</listitem><listitem><para><computeroutput>$XAPPLRESDIR/uid/</computeroutput> <emphasis>%U</emphasis></para>
</listitem><listitem><para><computeroutput>$HOME/uid/</computeroutput> <emphasis>%U</emphasis></para>
</listitem><listitem><para><computeroutput>$HOME/</computeroutput> <emphasis>%U</emphasis></para>
</listitem><listitem><para><computeroutput>/usr/lib/X11/</computeroutput> <emphasis>%L</emphasis><computeroutput>/uid/</computeroutput><emphasis>%N</emphasis> <computeroutput>/</computeroutput><emphasis>%U</emphasis></para>
</listitem><listitem><para><computeroutput>/usr/lib/X11/</computeroutput> <emphasis>%l</emphasis><computeroutput>/uid/</computeroutput><emphasis>%N</emphasis> <computeroutput>/</computeroutput><emphasis>%U</emphasis></para>
</listitem><listitem><para><computeroutput>/usr/lib/X11/uid/</computeroutput> <emphasis>%N</emphasis><computeroutput>/</computeroutput><emphasis>%U</emphasis></para>
</listitem><listitem><para><computeroutput>/usr/lib/X11/</computeroutput> <emphasis>%L</emphasis><computeroutput>/uid/</computeroutput><emphasis>%U</emphasis></para>
</listitem><listitem><para><computeroutput>/usr/lib/X11/</computeroutput> <emphasis>%l</emphasis><computeroutput>/uid/</computeroutput><emphasis>%U</emphasis></para>
</listitem><listitem><para><computeroutput>/usr/lib/X11/uid/</computeroutput> <emphasis>%U</emphasis></para>
</listitem><listitem><para><computeroutput>/usr/include/X11/uid/</computeroutput> <emphasis>%U</emphasis></para>
</listitem></orderedlist>
<para>If the <systemitem>XAPPLRESDIR</systemitem> environment variable is
not set, the <computeroutput>MrmOpenHierarchy()</computeroutput> function
uses <computeroutput>$HOME</computeroutput> instead of the<systemitem>XAPPLRESDIR</systemitem> environment variable.</para>
</sect3>
</sect2>
<sect2 id="IPG.motif.div.28">
<title>default_charset Character Set in UIL<indexterm><primary>User Interface
Language (UIL), see UIL &lt;$nopage></primary></indexterm><indexterm><primary>default_charset string literal</primary></indexterm><indexterm><primary>string literals</primary><secondary>default_charset in UIL</secondary></indexterm><indexterm><primary>default_charset
string literal</primary></indexterm></title>
<para>With the default_charset string literal, any characters can be set as
a valid string literal. For example, if the <systemitem>LANG</systemitem>
environment variable is <computeroutput>el_GR</computeroutput>, the string
literal with default_charset can contain any Greek character. If the <systemitem>LANG</systemitem> environment variable is <computeroutput>ja_JP</computeroutput>,
the default_charset string literal can contain any Japanese character encoded
in Japanese EUC.</para>
<para>If no character set is set to a string literal, the character set of
the string literal is set as cur_charset. And, in the system environment,
the cur_charset value is always set as default_charset.</para>
<sect3 id="IPG.motif.div.29">
<title>Example<indexterm><primary>UIL (User Interface Language)</primary>
<secondary>sample Japanese and English program</secondary></indexterm>: uil_sample</title>
<para><!--Original XRef content: 'Figure&numsp;4&hyphen;4'--><xref role="CodeOrFigureOrTable"
linkend="IPG.motif.mkr.14"> shows a UIL sample program on English and Japanese
environments.</para>
<figure>
<title id="IPG.motif.mkr.14">Sample UIL program on English and Japanese environments</title>
<graphic id="IPG.motif.grph.4" entityref="IPG.motif.fig.4"></graphic>
</figure>
<para>In the following sample program, <emphasis>LLL</emphasis> indicates
locale text, which can be Japanese, Korean, Traditional Chinese, Greek, French,
or others.</para>
<programlisting>uil_sample.uil
!
! sample uil file - uil_sample.uil
!
! C source file - uil_sample.c
!
! Resource file - uil-sample.resource
!
module Test
version = 'v1.0'
names = case_sensitive
objects = {
XmPushButton = gadget;
}
!************************************
! declare callback procedure
!************************************
procedure
exit_CB;
!***************************************************************
! declare BulletinBoard as parent of PushButton and Text
!***************************************************************
object
bb: XmBulletinBoard {
arguments{
XmNwidth = 500;
XmNheight = 200;
};
controls{
XmPushButton pb1;
XmText text1;
};
};
!****************************
! declare PushButton
!****************************
object
pb1: XmPushButton {
arguments{
XmNlabelString = #Normal &ldquo;<emphasis>LLL</emphasis>exit button <emphasis>LLL</emphasis>&rdquo;;
XmNx = 50;
XmNy = 50;
};
callbacks{
XmNactivateCallback = procedure exit_CB;
};
};
!*********************
! declare Text
!*********************
text1: XmText {
arguments{
XmNx = 50;
XmNy = 150;
};
};
end module;
*
* C source file - uil_sample.c
*
*/
#include &lt;Mrm/MrmAppl.h>
#include &lt;locale.h>
void exit_CB();
static MrmHierarchy hierarchy;
static MrmType *class;
/******************************************/
/* specify the UID hierarchy list */
/*****************************************/
static char *aray_file[]=
{&ldquo;uil_sample.uid&rdquo;
};
static int num_file = (sizeof aray_file / sizeof
aray_file[0]);
/******************************************************/
/* define the mapping between UIL procedure names */
/* and their addresses */
/******************************************************/
static MRMRegisterArg reglist[]={
{&ldquo;exit_CB&rdquo;,(caddr_t) exit_CB}</programlisting>
</sect3>
</sect2>
<sect2 id="IPG.motif.div.30">
<title>Compound Strings in UIL<indexterm><primary>compound strings</primary>
<secondary>in UIL</secondary></indexterm></title>
<para>Three mechanisms exist for specifying strings in UIL files:</para>
<itemizedlist remap="Bullet1"><listitem><para>As string literals, which may
be stored in UID files as either null-terminated strings or compound strings
</para>
</listitem><listitem><para>As compound strings</para>
</listitem><listitem><para>As wide character strings</para>
</listitem></itemizedlist>
<para>Both string literals and compound strings consist of text, a character
set, and a writing direction. For string literals and for compound strings
with no explicit direction, UIL infers the writing direction from the character
set. The UIL concatenation operator (&amp;) concatenates both string literals
and compound strings.</para>
<para>Regardless of whether UIL stores string literals in UID files as null-terminated
strings or as compound<indexterm><primary>string literals</primary><secondary>in UID files</secondary></indexterm> strings, it stores information about
each string's character set and writing direction along with the text. In
general, UIL stores string literals or string expressions as compound strings
in UID files under the following conditions:</para>
<itemizedlist remap="Bullet1"><listitem><para>When a string expression consists
of two or more literals with different character sets or writing directions
</para>
</listitem><listitem><para>When the literal or expression is used as a value
that has a compound string data type (such as the value of a resource whose
data type is compound string)</para>
</listitem></itemizedlist>
<para>UIL recognizes a number of keywords specifying character sets. UIL associates
parsing<indexterm><primary>character set keywords</primary></indexterm><indexterm>
<primary>character sets, defining with UIL CHARACTER_SET function</primary>
</indexterm><indexterm><primary>string literals</primary><secondary>syntax</secondary></indexterm> rules, including parsing direction and whether characters
have 8 or 16 bits, for each character set it recognizes. It is also possible
to define a character set using the UIL <command>CHARACTER_SET</command> function.
</para>
<para>The syntax of a string literal is one of the following:</para>
<itemizedlist remap="Bullet1"><listitem><para>'[<symbol role="Variable">character_string</symbol>]'</para>
</listitem><listitem><para>[#<symbol role="Variable">char_set</symbol>]</para>
</listitem><listitem><para>&ldquo;[<symbol role="Variable">character_string</symbol>]&rdquo;</para>
</listitem></itemizedlist>
<para>For each syntax, the character set of the string is determined as follows:
</para>
<itemizedlist remap="Bullet1"><listitem><para>For a string declared as ' <symbol>character_string</symbol>', the character set is the code set component of
the <systemitem>LANG</systemitem> environment variable, if it is set in the
UIL compilation environment; or it is the value of <computeroutput>XmFALLBACK_CHARSET</computeroutput> if the <systemitem>LANG</systemitem> environment variable
is not set or has no code set. By default, the value of <computeroutput>XmFALLBACK_CHARSET</computeroutput> is ISO8859-1, but vendors may supply
different values.</para>
</listitem><listitem><para>For a string declared as <literal>#</literal><symbol role="Variable">char_set</symbol> <literal>&ldquo;</literal> <symbol role="Variable">string</symbol><literal>&rdquo;</literal>, the character set is <symbol role="Variable">char_set</symbol>.</para>
</listitem><listitem><para>For a string declared as <literal>&ldquo;</literal><symbol role="Variable">character</symbol><literal>_</literal> <symbol role="Variable">string</symbol><literal>&rdquo;</literal>, the character set depends on whether
the module has a <filename>CHARACTER_SET</filename> clause and whether the
UIL compiler's <filename>use_setlocale_flag</filename> is set.</para>
<itemizedlist remap="Bullet2"><listitem><para>If the module has a <filename>CHARACTER_SET</filename> clause, the character set is the one specified in
that clause.</para>
</listitem><listitem><para>If the module has no <filename>CHARACTER_SET</filename>
clause but the <command>uil</command> command was started with the <computeroutput>-s</computeroutput> option, or if the <filename>Uil()</filename> function
was started with <command>use_setlocale_flag set</command>, UIL calls the <filename>setlocale()</filename> function and parses the string
in the current locale. The character set of the resulting string is <computeroutput>XmFONTLIST_DEFAULT_TAG</computeroutput>.</para>
</listitem><listitem><para>If the module has no <filename>CHARACTER_SET</filename>
clause and the <computeroutput>uil</computeroutput> command was started without
the <computeroutput>-s</computeroutput> option, or if the <filename>Uil()</filename> function was started without <filename>use_setlocale_flag</filename>, the character set is the code set component of the <systemitem>LANG</systemitem> environment variable, if it is set in the UIL compilation
environment, or the character set is the value of <computeroutput>XmFALLBACK_CHARSET</computeroutput> if <systemitem>LANG</systemitem> is not set or has no code
set.</para>
</listitem></itemizedlist>
</listitem></itemizedlist>
<para>UIL always stores a string specified using the <computeroutput>COMPOUND_STRING</computeroutput> function as a compound string. This function takes as arguments
a string expression and optional specifications of a character set, direction,
and whether to append a separator to the string. If no character set or direction
is specified, UIL derives it from the string expression, as described in
the preceding section.</para>
<note>
<para>Certain predefined escape sequences, beginning with a \ (backslash),
may be displayed in string literals, with the following exceptions: &ndash;
A string in single quotation marks can span multiple lines, with each
new line character escaped by a backslash. A string in double quotation
marks cannot span multiple lines. &ndash; Escape sequences are processed
literally inside a string that is parsed in the current locale (a localized
string).</para>
</note>
</sect2>
</sect1>
</chapter>
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