gtk_tut-9.html

gtk是linux一款强大的夸平台的图形化开发工具

int main( int argc, char *argv[] )
{
    /* GtkWidget is the storage type for widgets */
    GtkWidget *window, *pixmapwid, *button;
    GdkPixmap *pixmap;
    GdkBitmap *mask;
    GtkStyle *style;
    
    /* create the main window, and attach delete_event signal to terminating
       the application */
    gtk_init( &argc, &argv );
    window = gtk_window_new( GTK_WINDOW_TOPLEVEL );
    gtk_signal_connect( GTK_OBJECT (window), "delete_event",
                        GTK_SIGNAL_FUNC (close_application), NULL );
    gtk_container_set_border_width( GTK_CONTAINER (window), 10 );
    gtk_widget_show( window );

    /* now for the pixmap from gdk */
    style = gtk_widget_get_style( window );
    pixmap = gdk_pixmap_create_from_xpm_d( window->window,  &mask,
                                           &style->bg[GTK_STATE_NORMAL],
                                           (gchar **)xpm_data );

    /* a pixmap widget to contain the pixmap */
    pixmapwid = gtk_pixmap_new( pixmap, mask );
    gtk_widget_show( pixmapwid );

    /* a button to contain the pixmap widget */
    button = gtk_button_new();
    gtk_container_add( GTK_CONTAINER(button), pixmapwid );
    gtk_container_add( GTK_CONTAINER(window), button );
    gtk_widget_show( button );

    gtk_signal_connect( GTK_OBJECT(button), "clicked",
                        GTK_SIGNAL_FUNC(button_clicked), NULL );

    /* show the window */
    gtk_main ();
          
    return 0;
}
/* example-end */
</PRE>
</CODE></BLOCKQUOTE>
<P>To load a file from an XPM data file called icon0.xpm in the current
directory, we would have created the pixmap thus
<P>
<BLOCKQUOTE><CODE>
<PRE>
    /* load a pixmap from a file */
    pixmap = gdk_pixmap_create_from_xpm( window->window, &amp;mask,
                                         &amp;style->bg[GTK_STATE_NORMAL],
                                         "./icon0.xpm" );
    pixmapwid = gtk_pixmap_new( pixmap, mask );
    gtk_widget_show( pixmapwid );
    gtk_container_add( GTK_CONTAINER(window), pixmapwid );
</PRE>
</CODE></BLOCKQUOTE>
<P>A disadvantage of using pixmaps is that the displayed object is always
rectangular, regardless of the image. We would like to create desktops
and applications with icons that have more natural shapes. For
example, for a game interface, we would like to have round buttons to
push. The way to do this is using shaped windows.
<P>A shaped window is simply a pixmap where the background pixels are
transparent. This way, when the background image is multi-colored, we
don't overwrite it with a rectangular, non-matching border around our
icon. The following example displays a full wheelbarrow image on the
desktop.
<P>
<BLOCKQUOTE><CODE>
<PRE>
/* example-start wheelbarrow wheelbarrow.c */

#include &lt;gtk/gtk.h>

/* XPM */
static char * WheelbarrowFull_xpm[] = {
"48 48 64 1",
"       c None",
".      c #DF7DCF3CC71B",
"X      c #965875D669A6",
"o      c #71C671C671C6",
"O      c #A699A289A699",
"+      c #965892489658",
"@      c #8E38410330C2",
"#      c #D75C7DF769A6",
"$      c #F7DECF3CC71B",
"%      c #96588A288E38",
"&amp;      c #A69992489E79",
"*      c #8E3886178E38",
"=      c #104008200820",
"-      c #596510401040",
";      c #C71B30C230C2",
":      c #C71B9A699658",
">      c #618561856185",
",      c #20811C712081",
"&lt;      c #104000000000",
"1      c #861720812081",
"2      c #DF7D4D344103",
"3      c #79E769A671C6",
"4      c #861782078617",
"5      c #41033CF34103",
"6      c #000000000000",
"7      c #49241C711040",
"8      c #492445144924",
"9      c #082008200820",
"0      c #69A618611861",
"q      c #B6DA71C65144",
"w      c #410330C238E3",
"e      c #CF3CBAEAB6DA",
"r      c #71C6451430C2",
"t      c #EFBEDB6CD75C",
"y      c #28A208200820",
"u      c #186110401040",
"i      c #596528A21861",
"p      c #71C661855965",
"a      c #A69996589658",
"s      c #30C228A230C2",
"d      c #BEFBA289AEBA",
"f      c #596545145144",
"g      c #30C230C230C2",
"h      c #8E3882078617",
"j      c #208118612081",
"k      c #38E30C300820",
"l      c #30C2208128A2",
"z      c #38E328A238E3",
"x      c #514438E34924",
"c      c #618555555965",
"v      c #30C2208130C2",
"b      c #38E328A230C2",
"n      c #28A228A228A2",
"m      c #41032CB228A2",
"M      c #104010401040",
"N      c #492438E34103",
"B      c #28A2208128A2",
"V      c #A699596538E3",
"C      c #30C21C711040",
"Z      c #30C218611040",
"A      c #965865955965",
"S      c #618534D32081",
"D      c #38E31C711040",
"F      c #082000000820",
"                                                ",
"          .XoO                                  ",
"         +@#$%o&amp;                                ",
"         *=-;#::o+                              ",
"           >,&lt;12#:34                            ",
"             45671#:X3                          ",
"               +89&lt;02qwo                        ",
"e*                >,67;ro                       ",
"ty>                 459@>+&amp;&amp;                    ",
"$2u+                  >&lt;ipas8*                  ",
"%$;=*                *3:.Xa.dfg>                ",
"Oh$;ya             *3d.a8j,Xe.d3g8+             ",
" Oh$;ka          *3d$a8lz,,xxc:.e3g54           ",
"  Oh$;kO       *pd$%svbzz,sxxxxfX..&amp;wn>         ",
"   Oh$@mO    *3dthwlsslszjzxxxxxxx3:td8M4       ",
"    Oh$@g&amp; *3d$XNlvvvlllm,mNwxxxxxxxfa.:,B*     ",
"     Oh$@,Od.czlllllzlmmqV@V#V@fxxxxxxxf:%j5&amp;   ",
"      Oh$1hd5lllslllCCZrV#r#:#2AxxxxxxxxxcdwM*  ",
"       OXq6c.%8vvvllZZiqqApA:mq:Xxcpcxxxxxfdc9* ",
"        2r&lt;6gde3bllZZrVi7S@SV77A::qApxxxxxxfdcM ",
"        :,q-6MN.dfmZZrrSS:#riirDSAX@Af5xxxxxfevo",
"         +A26jguXtAZZZC7iDiCCrVVii7Cmmmxxxxxx%3g",
"          *#16jszN..3DZZZZrCVSA2rZrV7Dmmwxxxx&amp;en",
"           p2yFvzssXe:fCZZCiiD7iiZDiDSSZwwxx8e*>",
"           OA1&lt;jzxwwc:$d%NDZZZZCCCZCCZZCmxxfd.B ",
"            3206Bwxxszx%et.eaAp77m77mmmf3&amp;eeeg* ",
"             @26MvzxNzvlbwfpdettttttttttt.c,n&amp;  ",
"             *;16=lsNwwNwgsvslbwwvccc3pcfu&lt;o    ",
"              p;&lt;69BvwwsszslllbBlllllllu&lt;5+     ",
"              OS0y6FBlvvvzvzss,u=Blllj=54       ",
"               c1-699Blvlllllu7k96MMMg4         ",
"               *10y8n6FjvllllB&lt;166668           ",
"                S-kg+>666&lt;M&lt;996-y6n&lt;8*          ",
"                p71=4 m69996kD8Z-66698&amp;&amp;        ",
"                &amp;i0ycm6n4 ogk17,0&lt;6666g         ",
"                 N-k-&lt;>     >=01-kuu666>        ",
"                 ,6ky&amp;      &amp;46-10ul,66,        ",
"                 Ou0&lt;>       o66y&lt;ulw&lt;66&amp;       ",
"                  *kk5       >66By7=xu664       ",
"                   &lt;&lt;M4      466lj&lt;Mxu66o       ",
"                   *>>       +66uv,zN666*       ",
"                              566,xxj669        ",
"                              4666FF666>        ",
"                               >966666M         ",
"                                oM6668+         ",
"                                  *4            ",
"                                                ",
"                                                "};


/* When invoked (via signal delete_event), terminates the application */
void close_application( GtkWidget *widget, GdkEvent *event, gpointer data ) {
    gtk_main_quit();
}

int main (int argc, char *argv[])
{
    /* GtkWidget is the storage type for widgets */
    GtkWidget *window, *pixmap, *fixed;
    GdkPixmap *gdk_pixmap;
    GdkBitmap *mask;
    GtkStyle *style;
    GdkGC *gc;
    
    /* Create the main window, and attach delete_event signal to terminate
     * the application.  Note that the main window will not have a titlebar
     * since we're making it a popup. */
    gtk_init (&amp;argc, &amp;argv);
    window = gtk_window_new( GTK_WINDOW_POPUP );
    gtk_signal_connect (GTK_OBJECT (window), "delete_event",
                        GTK_SIGNAL_FUNC (close_application), NULL);
    gtk_widget_show (window);

    /* Now for the pixmap and the pixmap widget */
    style = gtk_widget_get_default_style();
    gc = style->black_gc;
    gdk_pixmap = gdk_pixmap_create_from_xpm_d( window->window, &amp;mask,
                                             &amp;style->bg[GTK_STATE_NORMAL],
                                             WheelbarrowFull_xpm );
    pixmap = gtk_pixmap_new( gdk_pixmap, mask );
    gtk_widget_show( pixmap );

    /* To display the pixmap, we use a fixed widget to place the pixmap */
    fixed = gtk_fixed_new();
    gtk_widget_set_usize( fixed, 200, 200 );
    gtk_fixed_put( GTK_FIXED(fixed), pixmap, 0, 0 );
    gtk_container_add( GTK_CONTAINER(window), fixed );
    gtk_widget_show( fixed );

    /* This masks out everything except for the image itself */
    gtk_widget_shape_combine_mask( window, mask, 0, 0 );
    
    /* show the window */
    gtk_widget_set_uposition( window, 20, 400 );
    gtk_widget_show( window );
    gtk_main ();
          
    return(0);
}
/* example-end */
</PRE>
</CODE></BLOCKQUOTE>
<P>To make the wheelbarrow image sensitive, we could attach the button
press event signal to make it do something. The following few lines
would make the picture sensitive to a mouse button being pressed which
makes the application terminate.
<P>
<BLOCKQUOTE><CODE>
<PRE>
    gtk_widget_set_events( window,
                          gtk_widget_get_events( window ) |
                          GDK_BUTTON_PRESS_MASK );

   gtk_signal_connect( GTK_OBJECT(window), "button_press_event",
                       GTK_SIGNAL_FUNC(close_application), NULL );
</PRE>
</CODE></BLOCKQUOTE>
<P>
<H2><A NAME="ss9.7">9.7 Rulers</A>
</H2>

<P>Ruler widgets are used to indicate the location of the mouse pointer
in a given window. A window can have a vertical ruler spanning across
the width and a horizontal ruler spanning down the height. A small
triangular indicator on the ruler shows the exact location of the
pointer relative to the ruler.
<P>A ruler must first be created. Horizontal and vertical rulers are
created using
<P>
<BLOCKQUOTE><CODE>
<PRE>
GtkWidget *gtk_hruler_new( void );    /* horizontal ruler */

GtkWidget *gtk_vruler_new( void );    /* vertical ruler   */
</PRE>
</CODE></BLOCKQUOTE>
<P>Once a ruler is created, we can define the unit of measurement. Units
of measure for rulers can be GTK_PIXELS, GTK_INCHES or
GTK_CENTIMETERS. This is set using
<P>
<BLOCKQUOTE><CODE>
<PRE>
void gtk_ruler_set_metric( GtkRuler      *ruler,
                           GtkMetricType  metric );
</PRE>
</CODE></BLOCKQUOTE>
<P>The default measure is GTK_PIXELS.
<P>
<BLOCKQUOTE><CODE>
<PRE>
    gtk_ruler_set_metric( GTK_RULER(ruler), GTK_PIXELS );
</PRE>
</CODE></BLOCKQUOTE>
<P>Other important characteristics of a ruler are how to mark the units
of scale and where the position indicator is initially placed. These
are set for a ruler using
<P>
<BLOCKQUOTE><CODE>
<PRE>
void gtk_ruler_set_range( GtkRuler *ruler,
                          gfloat    lower,
                          gfloat    upper,
                          gfloat    position,
                          gfloat    max_size );
</PRE>
</CODE></BLOCKQUOTE>
<P>The lower and upper arguments define the extent of the ruler, and
max_size is the largest possible number that will be displayed.
Position defines the initial position of the pointer indicator within
the ruler.
<P>A vertical ruler can span an 800 pixel wide window thus
<P>
<BLOCKQUOTE><CODE>
<PRE>
    gtk_ruler_set_range( GTK_RULER(vruler), 0, 800, 0, 800);
</PRE>
</CODE></BLOCKQUOTE>
<P>The markings displayed on the ruler will be from 0 to 800, with a
number for every 100 pixels. If instead we wanted the ruler to range
from 7 to 16, we would code
<P>
<BLOCKQUOTE><CODE>
<PRE>
    gtk_ruler_set_range( GTK_RULER(vruler), 7, 16, 0, 20);
</PRE>
</CODE></BLOCKQUOTE>
<P>The indicator on the ruler is a small triangular mark that indicates
the position of the pointer relative to the ruler. If the ruler is
used to follow the mouse pointer, the motion_notify_event signal
should be connected to the motion_notify_event method of the ruler.
To follow all mouse movements within a window area, we would use
<P>
<BLOCKQUOTE><CODE>
<PRE>
#define EVENT_METHOD(i, x) GTK_WIDGET_CLASS(GTK_OBJECT(i)->klass)->x

    gtk_signal_connect_object( GTK_OBJECT(area), "motion_notify_event",
           (GtkSignalFunc)EVENT_METHOD(ruler, motion_notify_event),
           GTK_OBJECT(ruler) );
</PRE>
</CODE></BLOCKQUOTE>
<P>The following example creates a drawing area with a horizontal ruler
above it and a vertical ruler to the left of it. The size of the
drawing area is 600 pixels wide by 400 pixels high. The horizontal
ruler spans from 7 to 13 with a mark every 100 pixels, while the
vertical ruler spans from 0 to 400 with a mark every 100 pixels.
Placement of the drawing area and the rulers is done using a table.
<P>
<BLOCKQUOTE><CODE>
<PRE>
/* example-start rulers rulers.c */

#include &lt;gtk/gtk.h>

#define EVENT_METHOD(i, x) GTK_WIDGET_CLASS(GTK_OBJECT(i)->klass)->x

#define XSIZE  600
#define YSIZE  400

/* This routine gets control when the close button is clicked */
void close_application( GtkWidget *widget, GdkEvent *event, gpointer data ) {
    gtk_main_quit();
}

/* The main routine */
int main( int argc, char *argv[] ) {
    GtkWidget *window, *table, *area, *hrule, *vrule;