pygtk-layout container

布局容器(The Layout container)与固定容器(the Fixed container)类似，不过它可以在一个无限的滚动区域定位构件(其实也不能大于2^32像素)。在X系统中，窗口的宽度和高度只能限于在32767像素以你。布局容器构件使用一些特殊的技巧(doing some exotic stuff using window and bit gravities)越过这种限制。所以，即使在滚动区域你有很多子构件，也可以平滑地滚动。

用以下函数创建布局容器：

GtkWidget *gtk_layout_new( GtkAdjustment *hadjustment,
                           GtkAdjustment *vadjustment );

可以看到，你可以有选择地指定布局容器滚动时要使用的调整对象。

你可以用下面的两个函数在布局容器构件你添加和移动构件。

void gtk_layout_put( GtkLayout *layout,
                     GtkWidget *widget,
                     gint       x,
                     gint       y );

void gtk_layout_move( GtkLayout *layout,
                      GtkWidget *widget,
                      gint       x,
                      gint       y );

布局容器构件的尺寸可以用接下来的这个函数指定：

void gtk_layout_set_size( GtkLayout *layout,
                          guint      width,
                          guint      height );

最后4个函数用于操纵垂直和水平的调整对象。

GtkAdjustment* gtk_layout_get_hadjustment( GtkLayout *layout );

GtkAdjustment* gtk_layout_get_vadjustment( GtkLayout *layout );

void gtk_layout_set_hadjustment( GtkLayout     *layout,
                                 GtkAdjustment *adjustment );

void gtk_layout_set_vadjustment( GtkLayout     *layout,
                                 GtkAdjustment *adjustment);

#!/usr/bin/env python

# example layout.py

import pygtk
pygtk.require('2.0')
import gtk
import random

class LayoutExample:
     def WindowDeleteEvent(self, widget, event):
     # return false so that window will be destroyed
         return False

     def WindowDestroy(self, widget, *data):
     # exit main loop
        gtk.main_quit()     

     def ButtonClicked(self, button):
     # move the button
        self.layout.move(button, random.randint(0,500),
        random.randint(0,500))

     def __init__(self):
     # create the top level window
        window = gtk.Window(gtk.WINDOW_TOPLEVEL)
        window.set_title("Layout Example")
        window.set_default_size(300, 300)
        window.connect("delete-event", self.WindowDeleteEvent)
        window.connect("destroy", self.WindowDestroy)
        # create the table and pack into the window
        table = gtk.Table(2, 2, False)
        window.add(table)
        # create the layout widget and pack into the table
        self.layout = gtk.Layout(None, None)
        self.layout.set_size(600, 600)
        table.attach(self.layout, 0, 1, 0, 1, gtk.FILL|gtk.EXPAND,
        gtk.FILL|gtk.EXPAND, 0, 0)
        # create the scrollbars and pack into the table
        vScrollbar = gtk.VScrollbar(None)
        table.attach(vScrollbar, 1, 2, 0, 1, gtk.FILL|gtk.SHRINK,
        gtk.FILL|gtk.SHRINK, 0, 0)
        hScrollbar = gtk.HScrollbar(None)
        table.attach(hScrollbar, 0, 1, 1, 2, gtk.FILL|gtk.SHRINK,
        gtk.FILL|gtk.SHRINK, 0, 0)
        # tell the scrollbars to use the layout widget’s adjustments
        vAdjust = self.layout.get_vadjustment()
        vScrollbar.set_adjustment(vAdjust)
        hAdjust = self.layout.get_hadjustment()
        hScrollbar.set_adjustment(hAdjust)
        # create 3 buttons and put them into the layout widget
        button = gtk.Button("Press Me")
        button.connect("clicked", self.ButtonClicked)
        self.layout.put(button, 0, 0)
        button = gtk.Button("Press Me")
        button.connect("clicked", self.ButtonClicked)
        self.layout.put(button, 100, 0)
        button = gtk.Button("Press Me")
        button.connect("clicked", self.ButtonClicked)
        self.layout.put(button, 200, 0)
        # show all the widgets
        window.show_all()

def main():
 # enter the main loop
    gtk.main()
    return 0

if __name__ == "__main__":
    LayoutExample()
    main()