Examples/simple_extensions/simple_tool.py

# Copyright (C) 2002 by Intevation GmbH
# Authors:
# Bernhard Herzog <[email protected]>
#
# This program is free software under the GPL (>=v2)
# Read the file COPYING coming with Thuban for details.

"""
Extend thuban with a simple tool.
"""

__version__ = "$Revision$"

# First import some things we need later.
import os
from math import hypot
from Thuban.UI.command import registry, Command
import Thuban.UI.mainwindow
from Thuban.UI.view import Tool


# A tool is a class usually derived from the Tool class. The tool class
# provides some standard methods to handle mouse events. It maintains a
# few instance variables that can be used when processing mouse events:
# self.start is the point where the user started to drag, self.current
# is the current position, self.dragging is true while the user is
# moving the mouse with the (left) button pressed.

class SimpleTool(Tool):

    """A Simple Tool"""

    def Name(self):
        """Return the string 'SimpleTool'."""
        # The return value is used to identify tools easily
        return "SimpleTool"

    def map_distance(self):
        """Return the distance on the map between the start and current point
        """
        # self.view is the canvas window the tool instance is working
        # on. Its win_to_proj method computes the coordinates in the
        # projected map coordinates for a given point in window
        # coordinates
        sx, sy = apply(self.view.win_to_proj, self.start)
        x, y = apply(self.view.win_to_proj, self.current)
        return hypot(x - sx, y - sy)

    def MouseMove(self, event):
        """Called by the canvas window when the mouse moves"""
        # The self.dragging flag is true, if the user is currently
        # dragging the mouse. Code in the Tool class has already handled
        # the button press event to set this flag.
        if self.dragging:
            # Call the inherited method to update some internal data
            # (self.start, etc.)
            Tool.MouseMove(self, event)
            print "SimpleTool: current distance", self.map_distance()

    def MouseUp(self, event):
        if self.dragging:
            Tool.MouseUp(self, event)
            print "SimpleTool: final distance", self.map_distance()


# the function implementing the "SimpleTool" command. Set the tool of
# the canvas to SimpleTool
def simple_tool(context):
    canvas = context.canvas
    canvas.tool = SimpleTool(canvas)


# Add the command to the registry. A command is represented by a Command
# instance. Here it's instantiated with the the name of the command,
# it's title and the function to call when the command is invoked by the
# user as positional arguments. The name is used internally to identify
# commands. The title is displayed in the menus.
#
# The icon keyword argument is optional and only useful if the command
# is used in a toolbar. It should be the name of an XPM file without the
# .xpm extension which will be automatically appended. We assume here
# that the icon's XPM file is located in the same directory as this
# module.
#
# The helptext keyword argument is an optinonal helptext.
#
# The checked keyword argument is an optional function to determine
# whether the button or menu item should be checked. It's called with
# the context. If the checked argument is not given the button or menu
# item will be a normal command button/item.

def check_simple_tool(context):
    """Return if the current tool of the context is the simple tool"""
    # the CurrentTool() method of the canvas returns the result of the
    # tool's Name method so we just have to compare it to "SimpleTool"
    return context.canvas.CurrentTool() == "SimpleTool"

iconfile = os.path.abspath(os.path.join(os.path.split(__file__)[0],
                                        "simple_tool"))
registry.Add(Command("simple_tool", "Simple Tool", simple_tool,
                     icon = iconfile, helptext = "Simple Tool",
                     checked = check_simple_tool))

# Add the command to the toolbar
Thuban.UI.mainwindow.main_toolbar.InsertSeparator()
Thuban.UI.mainwindow.main_toolbar.InsertItem("simple_tool")
1	bh	208	# Copyright (C) 2002 by Intevation GmbH
2			# Authors:
3			# Bernhard Herzog <[email protected]>
4			#
5			# This program is free software under the GPL (>=v2)
6			# Read the file COPYING coming with Thuban for details.
7
8			"""
9			Extend thuban with a simple tool.
10			"""
11
12			__version__ = "$Revision$"
13
14			# First import some things we need later.
15			import os
16			from math import hypot
17			from Thuban.UI.command import registry, Command
18			import Thuban.UI.mainwindow
19			from Thuban.UI.view import Tool
20
21
22			# A tool is a class usually derived from the Tool class. The tool class
23			# provides some standard methods to handle mouse events. It maintains a
24			# few instance variables that can be used when processing mouse events:
25			# self.start is the point where the user started to drag, self.current
26			# is the current position, self.dragging is true while the user is
27			# moving the mouse with the (left) button pressed.
28
29			class SimpleTool(Tool):
30
31			"""A Simple Tool"""
32
33			def Name(self):
34			"""Return the string 'SimpleTool'."""
35			# The return value is used to identify tools easily
36			return "SimpleTool"
37
38			def map_distance(self):
39			"""Return the distance on the map between the start and current point
40			"""
41			# self.view is the canvas window the tool instance is working
42			# on. Its win_to_proj method computes the coordinates in the
43			# projected map coordinates for a given point in window
44			# coordinates
45			sx, sy = apply(self.view.win_to_proj, self.start)
46			x, y = apply(self.view.win_to_proj, self.current)
47			return hypot(x - sx, y - sy)
48
49			def MouseMove(self, event):
50			"""Called by the canvas window when the mouse moves"""
51			# The self.dragging flag is true, if the user is currently
52			# dragging the mouse. Code in the Tool class has already handled
53			# the button press event to set this flag.
54			if self.dragging:
55			# Call the inherited method to update some internal data
56			# (self.start, etc.)
57			Tool.MouseMove(self, event)
58			print "SimpleTool: current distance", self.map_distance()
59
60			def MouseUp(self, event):
61			if self.dragging:
62			Tool.MouseUp(self, event)
63			print "SimpleTool: final distance", self.map_distance()
64
65
66			# the function implementing the "SimpleTool" command. Set the tool of
67			# the canvas to SimpleTool
68			def simple_tool(context):
69			canvas = context.canvas
70			canvas.tool = SimpleTool(canvas)
71
72
73			# Add the command to the registry. A command is represented by a Command
74			# instance. Here it's instantiated with the the name of the command,
75			# it's title and the function to call when the command is invoked by the
76			# user as positional arguments. The name is used internally to identify
77			# commands. The title is displayed in the menus.
78			#
79			# The icon keyword argument is optional and only useful if the command
80			# is used in a toolbar. It should be the name of an XPM file without the
81			# .xpm extension which will be automatically appended. We assume here
82			# that the icon's XPM file is located in the same directory as this
83			# module.
84			#
85			# The helptext keyword argument is an optinonal helptext.
86			#
87			# The checked keyword argument is an optional function to determine
88			# whether the button or menu item should be checked. It's called with
89			# the context. If the checked argument is not given the button or menu
90			# item will be a normal command button/item.
91
92			def check_simple_tool(context):
93			"""Return if the current tool of the context is the simple tool"""
94			# the CurrentTool() method of the canvas returns the result of the
95			# tool's Name method so we just have to compare it to "SimpleTool"
96			return context.canvas.CurrentTool() == "SimpleTool"
97
98			iconfile = os.path.abspath(os.path.join(os.path.split(__file__)[0],
99			"simple_tool"))
100			registry.Add(Command("simple_tool", "Simple Tool", simple_tool,
101			icon = iconfile, helptext = "Simple Tool",
102			checked = check_simple_tool))
103
104			# Add the command to the toolbar
105			Thuban.UI.mainwindow.main_toolbar.InsertSeparator()
106			Thuban.UI.mainwindow.main_toolbar.InsertItem("simple_tool")
Name	Value
svn:eol-style	native
svn:keywords	Author Date Id Revision