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gtk 开发手册和参考文档。 包括gtk glib gdk等

          refresh (the next time you push, pop, or set the
          default), the text disappears forever, replaced by the
          top of the stack.
        </p>
        <p>
          <a href="z91.html#FL-APPBARTEXT">Figure 8</a> lists the
          functions to manipulate the status text. <tt class= 
          "FUNCTION">gnome_appbar_set_status()</tt> is used to set
          the transient status text; <tt class="FUNCTION">
          gnome_appbar_refresh()</tt> forces a refresh without
          changing the stack---this is useful to be sure any
          transient text has been cleared. The other functions
          should be obvious.
        </p>
        <p>
          Note that you can use the <tt class="CLASSNAME">
          GnomeAppBar</tt> as a simple label---one message at a
          time, always replacing the previous message---just stick
          to either setting the default or setting the transient
          text, and never use the stack.
        </p>
        <div class="FIGURE">
          <a name="FL-APPBARTEXT"></a>
          <div class="FUNCSYNOPSIS">
            <a name="FL-APPBARTEXT.SYNOPSIS"></a>
            <table border="0" bgcolor="#E0E0E0" width="100%">
              <tr>
                <td>
<pre class="FUNCSYNOPSISINFO">
#include &lt;libgnomeui/gnome-appbar.h&gt;
</pre>
                </td>
              </tr>
            </table>
            <p>
              <code><code class="FUNCDEF">void <tt class=
              "FUNCTION">
              gnome_appbar_set_status</tt></code>(GnomeAppBar* <tt
              class="PARAMETER"><i>appbar</i></tt>, const gchar*
              <tt class="PARAMETER"><i>status</i></tt>);</code>
            </p>
            <p>
              <code><code class="FUNCDEF">void <tt class=
              "FUNCTION">
              gnome_appbar_set_default</tt></code>(GnomeAppBar* <tt
              class="PARAMETER"><i>appbar</i></tt>, const gchar*
              <tt class="PARAMETER"><i>
              default_status</i></tt>);</code>
            </p>
            <p>
              <code><code class="FUNCDEF">void <tt class=
              "FUNCTION">gnome_appbar_push</tt></code>(GnomeAppBar*
              <tt class="PARAMETER"><i>appbar</i></tt>, const
              gchar* <tt class="PARAMETER"><i>
              status</i></tt>);</code>
            </p>
            <p>
              <code><code class="FUNCDEF">void <tt class=
              "FUNCTION">gnome_appbar_pop</tt></code>(GnomeAppBar*
              <tt class="PARAMETER"><i>appbar</i></tt>);</code>
            </p>
            <p>
              <code><code class="FUNCDEF">void <tt class=
              "FUNCTION">
              gnome_appbar_clear_stack</tt></code>(GnomeAppBar* <tt
              class="PARAMETER"><i>appbar</i></tt>);</code>
            </p>
            <p>
              <code><code class="FUNCDEF">void <tt class=
              "FUNCTION">
              gnome_appbar_refresh</tt></code>(GnomeAppBar* <tt
              class="PARAMETER"><i>appbar</i></tt>);</code>
            </p>
          </div>
          <p>
            <b>Figure 8. Setting <tt class="CLASSNAME">
            GnomeAppBar</tt> Text</b>
          </p>
        </div>
      </div>
      <div class="SECT2">
        <h2 class="SECT2">
          <a name="SEC-GTKSTATUSBAR"><tt class="CLASSNAME">
          GtkStatusbar</tt></a>
        </h2>
        <p>
          <tt class="CLASSNAME">GtkStatusbar</tt> has no default
          text or "transient" text, as in <tt class="CLASSNAME">
          GnomeAppBar</tt>; it only has a message stack. However,
          each message is tagged with a "context" identified by a
          string. When you pop a message off the stack, you must
          specify a context; the topmost message <i class=
          "EMPHASIS">in that context</i> is popped. If there are no
          messages in the context you specify, no text is popped.
          In essence, the <tt class="CLASSNAME">GtkStatusbar</tt>
          "pop" operation works only within namespaces. There's no
          way to unconditionally pop all messages or
          unconditionally pop the topmost message.
        </p>
        <p>
          In principle this lets different parts of the program use
          the statusbar without interfering with one another.
          However, in my experience there's no need for this. For
          example, Netscape doesn't even have a stack for its
          statusbar; its statusbar is simply a label. In general it
          is poor interface design to make anything <i class= 
          "EMPHASIS">essential</i> appear in the statusbar, since
          the user might not notice it. Accidentally deleting a
          message should not be a major worry.
        </p>
        <p>
          <a href="z91.html#FL-STATUSBAR">Figure 9</a> shows the
          <tt class="CLASSNAME">GtkStatusbar</tt> functions.
        </p>
        <p>
          To use the statusbar:
        </p>
        <ol type="1">
          <li>
            <p>
              First obtain a context ID with <tt class="FUNCTION">
              gtk_statusbar_get_context_id()</tt>; the <span class= 
              "STRUCTNAME">context_description</span> argument can
              be any string you like. &#13;
            </p>
          </li>
          <li>
            <p>
              Push a message onto the statusbar using <tt class= 
              "FUNCTION">gtk_statusbar_push()</tt>; the message is
              tagged with the given context ID. The return value is
              a message ID you can use to remove the message.
              (Unlike <tt class="CLASSNAME">GnomeAppBar</tt>, <tt
              class="CLASSNAME">GtkStatusbar</tt> lets you remove a
              message that isn't on top of the stack.)&#13;
            </p>
          </li>
          <li>
            <p>
              Eventually remove the message with <tt class=
              "FUNCTION">gtk_statusbar_remove()</tt> or <tt class= 
              "FUNCTION">gtk_statusbar_pop()</tt>. The former
              refers to a specific message by ID, the latter
              removes the topmost message in the supplied
              context.&#13;
            </p>
          </li>
        </ol>
        <p>
          Note that <tt class="FUNCTION">gtk_statusbar_push()</tt>
          pushes a message on top of all other messages, even those
          in other contexts; but <tt class="FUNCTION">
          gtk_statusbar_pop()</tt> will only pop from the context
          supplied. Contexts do not refer to separate stacks, they
          merely restrict which messages you are permitted to pop.
        </p>
        <div class="FIGURE">
          <a name="FL-STATUSBAR"></a>
          <div class="FUNCSYNOPSIS">
            <a name="FL-STATUSBAR.SYNOPSIS"></a>
            <table border="0" bgcolor="#E0E0E0" width="100%">
              <tr>
                <td>
<pre class="FUNCSYNOPSISINFO">
#include &lt;gtk/gtkstatusbar.h&gt;
</pre>
                </td>
              </tr>
            </table>
            <p>
              <code><code class="FUNCDEF">GtkWidget* <tt class= 
              "FUNCTION">
              gtk_statusbar_new</tt></code>(void);</code>
            </p>
            <p>
              <code><code class="FUNCDEF">guint <tt class=
              "FUNCTION">
              gtk_statusbar_get_context_id</tt></code>(GtkStatusbar*
              <tt class="PARAMETER"><i>statusbar</i></tt>, const
              gchar* <tt class="PARAMETER"><i>
              context_description</i></tt>);</code>
            </p>
            <p>
              <code><code class="FUNCDEF">guint <tt class=
              "FUNCTION">
              gtk_statusbar_push</tt></code>(GtkStatusbar* <tt
              class="PARAMETER"><i>statusbar</i></tt>, guint <tt
              class="PARAMETER"><i>context_id</i></tt>, const
              gchar* <tt class="PARAMETER"><i>
              text</i></tt>);</code>
            </p>
            <p>
              <code><code class="FUNCDEF">void <tt class=
              "FUNCTION">
              gtk_statusbar_pop</tt></code>(GtkStatusbar* <tt
              class="PARAMETER"><i>statusbar</i></tt>, guint <tt
              class="PARAMETER"><i>context_id</i></tt>);</code>
            </p>
            <p>
              <code><code class="FUNCDEF">void <tt class=
              "FUNCTION">
              gtk_statusbar_remove</tt></code>(GtkStatusbar* <tt
              class="PARAMETER"><i>statusbar</i></tt>, guint <tt
              class="PARAMETER"><i>context_id</i></tt>, guint <tt
              class="PARAMETER"><i>message_id</i></tt>);</code>
            </p>
          </div>
          <p>
            <b>Figure 9. <tt class="CLASSNAME">
            GtkStatusbar</tt></b>
          </p>
        </div>
      </div>
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