controls/CustomToolTip.py
author Andrey Skvortsov <andrej.skvortzov@gmail.com>
Fri, 24 Aug 2018 13:41:43 +0300
changeset 2297 96ca6b056c55
parent 2229 3c94bac4526e
child 3303 0ffb41625592
permissions -rw-r--r--
Proper fix for error 'object has no attribute 'getSlave' in EtherCAT extension

traceback:
File "/home/developer/WorkData/PLC/beremiz/beremiz/IDEFrame.py", line 1433, in OnPouSelectedChanged
window.RefreshView()
File "/home/developer/WorkData/PLC/beremiz/beremiz/etherlab/ConfigEditor.py", line 837, in RefreshView
self.RefreshProcessVariables()
File "/home/developer/WorkData/PLC/beremiz/beremiz/etherlab/ConfigEditor.py", line 886, in RefreshProcessVariables
slaves = self.Controler.GetSlaves(**self.CurrentNodesFilter)
File "/home/developer/WorkData/PLC/beremiz/beremiz/etherlab/EthercatMaster.py", line 341, in GetSlaves
for slave in self.Config.getConfig().getSlave():
<type 'exceptions.AttributeError'>:_'lxml.etree._Element'_object_has_no_attribute_'getSlave'

Steps to reproduce problem:

- Add new EtherCAT master
- Add new EthercatNode to the master
- double click on


Revert commit "Dirty fix for error '_object_has_no_attribute_'getSlave' in EtherCAT extension"
[a3ac46366b86a0b237dac93be6b2281ac70b98a8].

The problem was that XML elements (proxy object) in some cases were created using custom XML
classes constructors and lxml.etree.Element() call and live python
patching. This causes that lxml backend doesn't know that custom python class
should be used for these XML elements.
Proxy object can be move/deleted and recreated by lxml
backend at any point in time or this can be done in python by copy/deepcopy operations.
If this happens, then newly created
proxy elements are using default class lxml.etree._Element. And all
custom functionality is lost.

All created XML elements should be always created through corresponding
parser and class lookup callback done by lxml backend.
It's described in more details in lxml documentation:
https://lxml.de/element_classes.html
#!/usr/bin/env python
# -*- coding: utf-8 -*-

# This file is part of Beremiz, a Integrated Development Environment for
# programming IEC 61131-3 automates supporting plcopen standard and CanFestival.
#
# Copyright (C) 2007: Edouard TISSERANT and Laurent BESSARD
#
# See COPYING file for copyrights details.
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.

from __future__ import absolute_import
import wx

from controls.CustomStyledTextCtrl import faces

TOOLTIP_MAX_CHARACTERS = 30  # Maximum number of characters by line in ToolTip
TOOLTIP_MAX_LINE = 5         # Maximum number of line in ToolTip
TOOLTIP_WAIT_PERIOD = 0.5    # Wait period before displaying tooltip in second

# -------------------------------------------------------------------------------
#                               Custom ToolTip
# -------------------------------------------------------------------------------


class CustomToolTip(wx.PopupWindow):
    """
    Class that implements a custom tool tip
    """

    def __init__(self, parent, tip, restricted=True):
        """
        Constructor
        @param parent: Parent window
        @param tip: Tip text (may be multiline)
        @param restricted: Tool tip must follow size restriction in line and
            characters number defined (default True)
        """
        wx.PopupWindow.__init__(self, parent)

        self.Restricted = restricted

        self.SetBackgroundStyle(wx.BG_STYLE_CUSTOM)
        self.SetTip(tip)

        # Initialize text font style
        self.Font = wx.Font(
            faces["size"],
            wx.SWISS,
            wx.NORMAL,
            wx.NORMAL,
            faceName=faces["mono"])

        self.Bind(wx.EVT_PAINT, self.OnPaint)

    def SetFont(self, font):
        """
        Set tool tip text font style
        @param font: wx.Font object containing font style
        """
        self.Font = font
        self.RefreshTip()

    def SetTip(self, tip):
        """
        Set tool tip text
        @param tip: Tool tip text
        """
        if self.Restricted:
            # Compute tip text line return
            self.Tip = []
            for line in tip.splitlines():
                if line != "":
                    words = line.split()
                    new_line = words[0]
                    for word in words[1:]:
                        # Add word to line
                        if len(new_line + " " + word) <= TOOLTIP_MAX_CHARACTERS:
                            new_line += " " + word
                        # Create new line
                        else:
                            self.Tip.append(new_line)
                            new_line = word
                    self.Tip.append(new_line)
                else:
                    self.Tip.append(line)

            # Restrict number of lines
            if len(self.Tip) > TOOLTIP_MAX_LINE:
                self.Tip = self.Tip[:TOOLTIP_MAX_LINE]

                # Add ... to the end of last line to indicate that tool tip
                # text is too long
                if len(self.Tip[-1]) < TOOLTIP_MAX_CHARACTERS - 3:
                    self.Tip[-1] += "..."
                else:
                    self.Tip[-1] = self.Tip[-1][:TOOLTIP_MAX_CHARACTERS - 3] + \
                                   "..."
        else:
            self.Tip = tip.splitlines()

        # Prevent to call wx method in non-wx threads
        wx.CallAfter(self.RefreshTip)

    def SetToolTipPosition(self, pos):
        """
        Set tool tip position
        @param pos: New tool tip position
        """
        # Get screen size to prevent tool tip to go out of the screen
        screen_width, screen_height = wx.GetDisplaySize()

        # Calculate position of tool tip to stay in screen limits
        tip_width, tip_height = self.GetToolTipSize()
        self.SetPosition(wx.Point(
            max(0, min(pos.x, screen_width - tip_width)),
            max(0, min(pos.y, screen_height - tip_height))))

    def GetToolTipSize(self):
        """
        Get tool tip size according to tip text and restriction
        @return: wx.Size(tool_tip_width, tool_tip_height)
        """
        max_width = max_height = 0

        # Create a memory DC for calculating text extent
        dc = wx.MemoryDC(wx.EmptyBitmap(1, 1))
        dc.SetFont(self.Font)

        # Compute max tip text size
        for line in self.Tip:
            w, h = dc.GetTextExtent(line)
            max_width = max(max_width, w)
            max_height += h

        return wx.Size(max_width + 4, max_height + 4)

    def RefreshTip(self):
        """
        Refresh tip on screen
        """
        # Prevent to call this function if tool tip destroyed
        if self:
            # Refresh tool tip size and position
            self.SetClientSize(self.GetToolTipSize())

            # Redraw tool tip
            self.Refresh()

    def OnPaint(self, event):
        """
        Callback for Paint Event
        @param event: Paint event
        """
        # Get buffered paint DC for tool tip
        dc = wx.AutoBufferedPaintDC(self)
        dc.Clear()

        # Set DC drawing style
        dc.SetPen(wx.BLACK_PEN)
        dc.SetBrush(wx.Brush(wx.Colour(255, 238, 170)))
        dc.SetFont(self.Font)

        # Draw Tool tip
        dc.BeginDrawing()
        tip_width, tip_height = self.GetToolTipSize()

        # Draw background rectangle
        dc.DrawRectangle(0, 0, tip_width, tip_height)

        # Draw tool tip text
        line_offset = 0
        for line in self.Tip:
            dc.DrawText(line, 2, line_offset + 2)
            _line_width, line_height = dc.GetTextExtent(line)
            line_offset += line_height

        dc.EndDrawing()

        event.Skip()