Question

Linux Mint 17，Python 2.7，wx'2.8.12.1'

我是wx的新手，可能，我无法做出正确的搜索队列。我已经通读了 Dialog's ShowModal() won't send EVT_PAINT 并尝试用self取代self.pnl，但显然不起作用。

代码来自“OpenCV with Python Blueprints”一书，见第19-21页。

我已经制作了丑陋的补丁以使其正常工作（在代码中标记），但对此情况感到好奇。

import cv2
import wx

class BaseLayout(wx.Frame):
    def __init__(self, parent, id, title, capture, fps=24):
        self.fps=fps
        self.capture = capture
        _, frame = self.capture.read()
        self.imgHeight,self.imgWidth = frame.shape[:2]
        self.bmp = wx.BitmapFromBuffer(self.imgWidth,
        self.imgHeight, frame)
        wx.Frame.__init__(self, parent, id, title,size=(self.imgWidth, self.imgHeight+20))
        self._init_base_layout()
        self._create_base_layout()
    def _init_base_layout(self):
        self.timer = wx.Timer(self)
        self.timer.Start(1000./self.fps)
        self.Bind(wx.EVT_TIMER, self._on_next_frame)
        self.Bind(wx.EVT_PAINT, self._on_paint)
    def _on_next_frame(self, event):
        ret, frame = self.capture.read()
        if ret:
            frame = self._process_frame(cv2.cvtColor(frame,cv2.COLOR_BGR2RGB))
            self.bmp.CopyFromBuffer(frame)
            self.Refresh(eraseBackground=False)#this intended to work
            deviceContext = wx.BufferedPaintDC(self.pnl)#this works (ugly patch from on_paint)
            deviceContext.DrawBitmap(self.bmp, 0, 0)#this works(ugly patch from on_paint)
    def _on_paint(self, event):
        print('I can never see this line')
        deviceContext = wx.BufferedPaintDC(self.pnl)
        deviceContext.DrawBitmap(self.bmp, 0, 0)
    def _create_base_layout(self):
        self.pnl = wx.Panel(self, -1,size=(self.imgWidth, self.imgHeight))
        self.pnl.SetBackgroundColour(wx.BLACK)
        self.panels_vertical = wx.BoxSizer(wx.VERTICAL)
        self.panels_vertical.Add(self.pnl, 1, flag=wx.EXPAND)
        self.SetMinSize((self.imgWidth, self.imgHeight))
        self.SetMaxSize((self.imgWidth, self.imgHeight))
        self.SetSizer(self.panels_vertical)
        self.Centre()
    def _process_frame(self, frame):
        return frame#stub

def main():
    capture = cv2.VideoCapture("ScreenFlow9.mov")
    if not(capture.isOpened()):
        capture.open()
    capture.set(cv2.cv.CV_CAP_PROP_FRAME_WIDTH, 640)
    capture.set(cv2.cv.CV_CAP_PROP_FRAME_HEIGHT, 480)
    app = wx.App()
    layout = BaseLayout(None, -1, 'Test', capture)
    layout.Show(True)
    app.MainLoop()
main()

Answer 1

框架没有获得EVT_PAINT事件，因为框架的客户区域都不可见。小组完全覆盖了它。

wx.Frame.Refresh不会发送wx.EVT_PAINT

1 个答案: