gtk-tut.sgml

linux下电话本所依赖的一些图形库

	/* This just does cleanup in GTK and exits with an exit status of 1. */
	exit (1);
    }
    
    which = atoi (argv[1]);

    /* Create our window */
    window = gtk_window_new (GTK_WINDOW_TOPLEVEL);

    /* You should always remember to connect the delete_event signal
     * to the main window. This is very important for proper intuitive
     * behavior */
    g_signal_connect (G_OBJECT (window), "delete_event",
		      G_CALLBACK (delete_event), NULL);
    gtk_container_set_border_width (GTK_CONTAINER (window), 10);
    
    /* We create a vertical box (vbox) to pack the horizontal boxes into.
     * This allows us to stack the horizontal boxes filled with buttons one
     * on top of the other in this vbox. */
    box1 = gtk_vbox_new (FALSE, 0);
    
    /* which example to show. These correspond to the pictures above. */
    switch (which) {
    case 1:
	/* create a new label. */
	label = gtk_label_new ("gtk_hbox_new (FALSE, 0);");
	
	/* Align the label to the left side.  We'll discuss this function and 
	 * others in the section on Widget Attributes. */
	gtk_misc_set_alignment (GTK_MISC (label), 0, 0);

	/* Pack the label into the vertical box (vbox box1).  Remember that 
	 * widgets added to a vbox will be packed one on top of the other in
	 * order. */
	gtk_box_pack_start (GTK_BOX (box1), label, FALSE, FALSE, 0);
	
	/* Show the label */
	gtk_widget_show (label);
	
	/* Call our make box function - homogeneous = FALSE, spacing = 0,
	 * expand = FALSE, fill = FALSE, padding = 0 */
	box2 = make_box (FALSE, 0, FALSE, FALSE, 0);
	gtk_box_pack_start (GTK_BOX (box1), box2, FALSE, FALSE, 0);
	gtk_widget_show (box2);

	/* Call our make box function - homogeneous = FALSE, spacing = 0,
	 * expand = TRUE, fill = FALSE, padding = 0 */
	box2 = make_box (FALSE, 0, TRUE, FALSE, 0);
	gtk_box_pack_start (GTK_BOX (box1), box2, FALSE, FALSE, 0);
	gtk_widget_show (box2);
	
	/* Args are: homogeneous, spacing, expand, fill, padding */
	box2 = make_box (FALSE, 0, TRUE, TRUE, 0);
	gtk_box_pack_start (GTK_BOX (box1), box2, FALSE, FALSE, 0);
	gtk_widget_show (box2);
	
	/* Creates a separator, we'll learn more about these later, 
	 * but they are quite simple. */
	separator = gtk_hseparator_new ();
	
        /* Pack the separator into the vbox. Remember each of these
         * widgets is being packed into a vbox, so they'll be stacked
	 * vertically. */
	gtk_box_pack_start (GTK_BOX (box1), separator, FALSE, TRUE, 5);
	gtk_widget_show (separator);
	
	/* Create another new label, and show it. */
	label = gtk_label_new ("gtk_hbox_new (TRUE, 0);");
	gtk_misc_set_alignment (GTK_MISC (label), 0, 0);
	gtk_box_pack_start (GTK_BOX (box1), label, FALSE, FALSE, 0);
	gtk_widget_show (label);
	
	/* Args are: homogeneous, spacing, expand, fill, padding */
	box2 = make_box (TRUE, 0, TRUE, FALSE, 0);
	gtk_box_pack_start (GTK_BOX (box1), box2, FALSE, FALSE, 0);
	gtk_widget_show (box2);
	
	/* Args are: homogeneous, spacing, expand, fill, padding */
	box2 = make_box (TRUE, 0, TRUE, TRUE, 0);
	gtk_box_pack_start (GTK_BOX (box1), box2, FALSE, FALSE, 0);
	gtk_widget_show (box2);
	
	/* Another new separator. */
	separator = gtk_hseparator_new ();
	/* The last 3 arguments to gtk_box_pack_start are:
	 * expand, fill, padding. */
	gtk_box_pack_start (GTK_BOX (box1), separator, FALSE, TRUE, 5);
	gtk_widget_show (separator);
	
	break;

    case 2:

	/* Create a new label, remember box1 is a vbox as created 
	 * near the beginning of main() */
	label = gtk_label_new ("gtk_hbox_new (FALSE, 10);");
	gtk_misc_set_alignment (GTK_MISC (label), 0, 0);
	gtk_box_pack_start (GTK_BOX (box1), label, FALSE, FALSE, 0);
	gtk_widget_show (label);
	
	/* Args are: homogeneous, spacing, expand, fill, padding */
	box2 = make_box (FALSE, 10, TRUE, FALSE, 0);
	gtk_box_pack_start (GTK_BOX (box1), box2, FALSE, FALSE, 0);
	gtk_widget_show (box2);
	
	/* Args are: homogeneous, spacing, expand, fill, padding */
	box2 = make_box (FALSE, 10, TRUE, TRUE, 0);
	gtk_box_pack_start (GTK_BOX (box1), box2, FALSE, FALSE, 0);
	gtk_widget_show (box2);
	
	separator = gtk_hseparator_new ();
	/* The last 3 arguments to gtk_box_pack_start are:
	 * expand, fill, padding. */
	gtk_box_pack_start (GTK_BOX (box1), separator, FALSE, TRUE, 5);
	gtk_widget_show (separator);
	
	label = gtk_label_new ("gtk_hbox_new (FALSE, 0);");
	gtk_misc_set_alignment (GTK_MISC (label), 0, 0);
	gtk_box_pack_start (GTK_BOX (box1), label, FALSE, FALSE, 0);
	gtk_widget_show (label);
	
	/* Args are: homogeneous, spacing, expand, fill, padding */
	box2 = make_box (FALSE, 0, TRUE, FALSE, 10);
	gtk_box_pack_start (GTK_BOX (box1), box2, FALSE, FALSE, 0);
	gtk_widget_show (box2);
	
	/* Args are: homogeneous, spacing, expand, fill, padding */
	box2 = make_box (FALSE, 0, TRUE, TRUE, 10);
	gtk_box_pack_start (GTK_BOX (box1), box2, FALSE, FALSE, 0);
	gtk_widget_show (box2);
	
	separator = gtk_hseparator_new ();
	/* The last 3 arguments to gtk_box_pack_start are: expand, fill, padding. */
	gtk_box_pack_start (GTK_BOX (box1), separator, FALSE, TRUE, 5);
	gtk_widget_show (separator);
	break;
    
    case 3:

        /* This demonstrates the ability to use gtk_box_pack_end() to
	 * right justify widgets. First, we create a new box as before. */
	box2 = make_box (FALSE, 0, FALSE, FALSE, 0);

	/* Create the label that will be put at the end. */
	label = gtk_label_new ("end");
	/* Pack it using gtk_box_pack_end(), so it is put on the right
	 * side of the hbox created in the make_box() call. */
	gtk_box_pack_end (GTK_BOX (box2), label, FALSE, FALSE, 0);
	/* Show the label. */
	gtk_widget_show (label);
	
	/* Pack box2 into box1 (the vbox remember ? :) */
	gtk_box_pack_start (GTK_BOX (box1), box2, FALSE, FALSE, 0);
	gtk_widget_show (box2);
	
	/* A separator for the bottom. */
	separator = gtk_hseparator_new ();
	/* This explicitly sets the separator to 400 pixels wide by 5 pixels
	 * high. This is so the hbox we created will also be 400 pixels wide,
	 * and the "end" label will be separated from the other labels in the
	 * hbox. Otherwise, all the widgets in the hbox would be packed as
	 * close together as possible. */
	gtk_widget_set_size_request (separator, 400, 5);
	/* pack the separator into the vbox (box1) created near the start 
	 * of main() */
	gtk_box_pack_start (GTK_BOX (box1), separator, FALSE, TRUE, 5);
	gtk_widget_show (separator);    
    }
    
    /* Create another new hbox.. remember we can use as many as we need! */
    quitbox = gtk_hbox_new (FALSE, 0);
    
    /* Our quit button. */
    button = gtk_button_new_with_label ("Quit");
    
    /* Setup the signal to terminate the program when the button is clicked */
    g_signal_connect_swapped (G_OBJECT (button), "clicked",
			      G_CALLBACK (gtk_main_quit),
			      G_OBJECT (window));
    /* Pack the button into the quitbox.
     * The last 3 arguments to gtk_box_pack_start are:
     * expand, fill, padding. */
    gtk_box_pack_start (GTK_BOX (quitbox), button, TRUE, FALSE, 0);
    /* pack the quitbox into the vbox (box1) */
    gtk_box_pack_start (GTK_BOX (box1), quitbox, FALSE, FALSE, 0);
    
    /* Pack the vbox (box1) which now contains all our widgets, into the
     * main window. */
    gtk_container_add (GTK_CONTAINER (window), box1);
    
    /* And show everything left */
    gtk_widget_show (button);
    gtk_widget_show (quitbox);
    
    gtk_widget_show (box1);
    /* Showing the window last so everything pops up at once. */
    gtk_widget_show (window);
    
    /* And of course, our main function. */
    gtk_main ();

    /* Control returns here when gtk_main_quit() is called, but not when 
     * exit() is used. */
    
    return 0;
}
<!-- example-end -->
</programlisting>

</sect1>

<!-- ----------------------------------------------------------------- -->
<sect1 id="sec-PackingUsingTables">
<title>Packing Using Tables</title>

<para>Let's take a look at another way of packing - Tables. These can be
extremely useful in certain situations.</para>

<para>Using tables, we create a grid that we can place widgets in. The
widgets may take up as many spaces as we specify.</para>

<para>The first thing to look at, of course, is the gtk_table_new() function:</para>

<programlisting role="C">
GtkWidget *gtk_table_new( guint    rows,
                          guint    columns,
                          gboolean homogeneous );
</programlisting>

<para>The first argument is the number of rows to make in the table, while
the second, obviously, is the number of columns.</para>

<para>The homogeneous argument has to do with how the table's boxes are
sized. If homogeneous is TRUE, the table boxes are resized to the size
of the largest widget in the table. If homogeneous is FALSE, the size
of a table boxes is dictated by the tallest widget in its same row,
and the widest widget in its column.</para>

<para>The rows and columns are laid out from 0 to n, where n was the number
specified in the call to gtk_table_new. So, if you specify rows = 2
and columns = 2, the layout would look something like this:</para>

<programlisting role="C">
 0          1          2
0+----------+----------+
 |          |          |
1+----------+----------+
 |          |          |
2+----------+----------+
</programlisting>

<para>Note that the coordinate system starts in the upper left hand corner.
To place a widget into a box, use the following function:</para>

<programlisting role="C">
void gtk_table_attach( GtkTable         *table,
                       GtkWidget        *child,
                       guint            left_attach,
                       guint            right_attach,
                       guint            top_attach,
                       guint            bottom_attach,
                       GtkAttachOptions xoptions,
                       GtkAttachOptions yoptions,
                       guint            xpadding,
                       guint            ypadding );
</programlisting>

<para>The first argument ("table") is the table you've created and the
second ("child") the widget you wish to place in the table.</para>

<para>The left and right attach arguments specify where to place the widget,
and how many boxes to use. If you want a button in the lower right
table entry of our 2x2 table, and want it to fill that entry <emphasis>only</emphasis>,
left_attach would be = 1, right_attach = 2, top_attach = 1,
bottom_attach = 2.</para>

<para>Now, if you wanted a widget to take up the whole top row of our 2x2
table, you'd use left_attach = 0, right_attach = 2, top_attach = 0,
bottom_attach = 1.</para>

<para>The xoptions and yoptions are used to specify packing options and may
be bitwise OR'ed together to allow multiple options.</para>

<para>These options are:</para>

<variablelist>
<varlistentry>
<term><literal>GTK_FILL</literal></term>
<listitem><para>If the table box is larger than the widget, and
<literal>GTK_FILL</literal> is specified, the widget will expand to use all the room
available.</para>
</listitem>
</varlistentry>

<varlistentry>
<term><literal>GTK_SHRINK</literal></term>
<listitem><para>If the table widget was allocated less space
then was requested (usually by the user resizing the window), then the
widgets would normally just be pushed off the bottom of the window and
disappear. If <literal>GTK_SHRINK</literal> is specified, the widgets will shrink
with the table.</para>
</listitem>
</varlistentry>

<varlistentry>
<term><literal>GTK_EXPAND</literal></term>
<listitem><para>This will cause the table to expand to use up
any remaining space in the window.</para>
</listitem>
</varlistentry>
</variablelist>

<para>Padding is just like in boxes, creating a clear area around the widget
specified in pixels.</para>

<para>gtk_table_attach() has a <emphasis>lot</emphasis> of options.  
So, there's a shortcut:</para>

<programlisting role="C">
void gtk_table_attach_defaults( GtkTable  *table,
                                GtkWidget *widget,
                                guint      left_attach,
                                guint      right_attach,
                                guint      top_attach,
                                guint      bottom_attach );
</programlisting>

<para>The X and Y options default to <literal>GTK_FILL | GTK_EXPAND</literal>, 
and X and Y padding are set to 0. The rest of the arguments are identical to the
previous function.</para>

<para>We also have gtk_table_set_row_spacing() and
gtk_table_set_col_spacing(). These places spacing between the rows at
the specified row or column.</para>

<programlisting role="C">
void gtk_table_set_row_spacing( GtkTable *table,
                                guint     row,
                                guint     spacing );
</programlisting>

<para>and</para>

<programlisting role="C">
void gtk_table_set_col_spacing ( GtkTable *table,
                                 guint     column,