PythonOCC进阶学习：界面设计——重新打造主界面

总目录 >> PythonOCC入门进阶到实战(目前已更新入门篇、基础篇和进阶篇)

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写在前面

刚开始的时候，只是比较多的关注功能层的实现，但是随着项目的推进，慢慢发现现有官方提供的主界面过于简单，再加上一些cad开发者也在不断地询问哪里有界面开发的教程，我想稍微总结一下之前做界面的经历，希望能够给大家一些启发和帮助。如果你觉得有用，关注下我，这就是对我最大的支持。

1.开发前提

首先要确认你已经安装了pyqt5，没有安装的，自行安装pip install pyqt5
关于使用pyside，wxpython的朋友，这方面我没太研究，但是本质应该差别不大。

本教程只是对主界面进行一个初步开发，如果你想拥有比较完善美观的界面，可以参考下这本书：pyqt5快速开发与实践

2.依赖文件 qtDisplay. py

将如下代码复制到名为qtDisplay. py，放到和主程序mainwindow（下面讲）同一文件夹

import logging
import os
import sys

from OCC.Display import OCCViewer

from PyQt5 import QtCore, QtGui, QtWidgets, QtOpenGL
# check if signal available, not available
# on PySide
HAVE_PYQT_SIGNAL = hasattr(QtCore, 'pyqtSignal')

logging.basicConfig(stream=sys.stdout, level=logging.DEBUG)
log = logging.getLogger(__name__)


class point(object):
    def __init__(self, obj=None):
        self.x = 0
        self.y = 0
        if obj is not None:
            self.set(obj)

    def set(self, obj):
        self.x = obj.x()
        self.y = obj.y()


class qtBaseViewer(QtOpenGL.QGLWidget):
    ''' The base Qt Widget for an OCC viewer
    '''

    def __init__(self, parent=None):
        QtOpenGL.QGLWidget.__init__(self, parent)
        self._display = None
        self._inited = False

        # enable Mouse Tracking
        self.setMouseTracking(True)
        # Strong focus
        self.setFocusPolicy(QtCore.Qt.WheelFocus)

        # required for overpainting the widget
        self.setAttribute(QtCore.Qt.WA_PaintOnScreen)
        self.setAttribute(QtCore.Qt.WA_NoSystemBackground)
        self.setAutoFillBackground(False)

    def GetHandle(self):
        ''' returns an the identifier of the GUI widget.
        It must be an integer
        '''
        win_id = self.winId()  # this returns either an int or voitptr

        if "%s" % type(win_id) == "<type 'PyCObject'>":  # PySide
            ### with PySide, self.winId() does not return an integer
            if sys.platform == "win32":
                ## Be careful, this hack is py27 specific
                ## does not work with python31 or higher
                ## since the PyCObject api was changed
                import ctypes
                ctypes.pythonapi.PyCObject_AsVoidPtr.restype = ctypes.c_void_p
                ctypes.pythonapi.PyCObject_AsVoidPtr.argtypes = [
                    ctypes.py_object]
                win_id = ctypes.pythonapi.PyCObject_AsVoidPtr(win_id)
        elif not isinstance(win_id, int):  # PyQt4 or 5
            ## below integer cast may be required because self.winId() can
            ## returns a sip.voitptr according to the PyQt version used
            ## as well as the python version
            win_id = int(win_id)
        return win_id

    def resizeEvent(self, event):
        if self._inited:
            super(qtBaseViewer,self).resizeEvent(event)
            self._display.OnResize()


class qtViewer3d(qtBaseViewer):

    # emit signal when selection is changed
    # is a list of TopoDS_*
    if HAVE_PYQT_SIGNAL:
        sig_topods_selected = QtCore.pyqtSignal(list)

    def __init__(self, *kargs):
        qtBaseViewer.__init__(self, *kargs)

        self.setObjectName("qt_viewer_3d")

        self._drawbox = False
        self._zoom_area = False
        self._select_area = False
        self._inited = False
        self._leftisdown = False
        self._middleisdown = False
        self._rightisdown = False
        self._selection = None
        self._drawtext = True
        self._qApp = QtWidgets.QApplication.instance(