我正在从python书创建一个小型绘图应用程序“wxPython in Action”,它使用self.GetClientSize()来获取窗口的大小。由于某种原因,这是我的返回(0,0)而不是预期的值(800,600)。
当调用wx.EmptyBitmap时,程序崩溃,其中0,0为其参数。如果我放 wx.EmptyBitmap(800,600)整个程序运行正常,减去调整大小。
以下是相关方法
def InitBuffer(self):
size = self.GetClientSizeTuple()
print size
sys.exit(1)
self.buffer = wx.EmptyBitmap(size.width, size.height)
dc = wx.BufferedDC(None, self.buffer)
dc.SetBackground(wx.Brush(self.GetBackgroundColour()))
dc.Clear()
self.DrawLines(dc)
self.reInitBuffer = False
这是完整的代码
#!/usr/bin/arch -i386 /usr/bin/python2.6 -tt
import sys
import wx
class SketchWindow(wx.Window):
def __init__(self, parent, ID):
wx.Window.__init__(self, parent, ID)
self.SetBackgroundColour("White")
self.color = "Black"
self.thickness = 1
self.pen = wx.Pen(self.color, self.thickness, wx.SOLID)
self.lines = []
self.curLine = []
self.pos = (0, 0)
self.InitBuffer()
self.Bind(wx.EVT_LEFT_DOWN, self.OnLeftDown)
self.Bind(wx.EVT_LEFT_UP, self.OnLeftUp)
self.Bind(wx.EVT_SIZE, self.OnSize)
self.Bind(wx.EVT_MOTION, self.OnMotion)
self.Bind(wx.EVT_IDLE, self.OnIdle)
self.Bind(wx.EVT_PAINT, self.OnPaint)
def InitBuffer(self):
size = self.GetClientSizeTuple()
print size
sys.exit(1)
self.buffer = wx.EmptyBitmap(size.width, size.height)
dc = wx.BufferedDC(None, self.buffer)
dc.SetBackground(wx.Brush(self.GetBackgroundColour()))
dc.Clear()
self.DrawLines(dc)
self.reInitBuffer = False
def GetLinesData(self):
return self.lines[:]
def SetLinesData(self, lines):
self.lines = lines[:]
self.InitBuffer()
self.Refresh()
def OnLeftDown(self, event):
self.curLine = []
self.pos = event.GetPositionTuple()
self.CaptureMouse()
def OnLeftUp(self, event):
if self.HasCapture():
self.lines.append((self.color, self.thickness, self.curLine))
self.curLine = []
self.ReleaseMouse()
def OnMotion(self, event):
if event.Dragging() and event.LeftIsDown():
dc = wx.BufferedDC(wx.ClientDC(self), self.buffer)
self.drawMotion(dc, event)
event.Skip()
def drawMotion(self, dc, event):
dc.SetPen(self.pen)
newPos = event.GetPositionTuple()
coords = self.pos + newPos
self.curLine.append(coords)
dc.DrawLine(*coords)
self.pos = newPos
def OnSize(self, event):
self.reInitBuffer = True
def OnIdle(self, event):
if self.reInitBuffer:
self.InitBuffer()
self.Refresh(False)
def OnPaint(self, event):
dc = wx.BufferedPaintDC(self, self.buffer)
def DrawLines(self, dc):
for (colour, thickness, line) in self.lines:
pen = wx.Pen(colour, thickness, wx.SOLID)
dc.SetPen(pen)
for coord in line:
dc.DrawLine(*coord)
def SetColor(self, color):
self.color = color
self.pen = wx.Pen(self.color, self.thickness, wx.SOLID)
def GetColor(self):
return self.color
def SetThickness(self, thickness):
self.thickness = thickness
self.pen = wx.Pen(self.color, self.thickness, wx.SOLID)
class SketchFrame(wx.Frame):
def __init__(self, parent):
wx.Frame.__init__(self, parent, -1, 'Sketch Frame', size=(800, 600))
self.sketch = SketchWindow(self, -1)
def main():
app = wx.PySimpleApp()
frame = SketchFrame(None)
frame.Show(True)
app.MainLoop()
if __name__ == '__main__':
main()
答案 0 :(得分:1)
我不知道是否有更好的解决方案,但问题是当对象初始化时它还没有父级,所以它不知道应该是什么大小。因此,它是宽度0和高度0.但是,它需要初始化缓冲区。我为解决这个问题做了什么
if size == (0, 0):
size.width = 1
size.height = 1
一旦将其添加到框架中,它将获得新的大小并调整缓冲区的大小。所以我猜这有用!
我认为另一个解决方案是将size参数传递给 init 方法,但如果不需要,我不希望这样做。
如果您有其他解决方案,请发布其他解决方案=)
答案 1 :(得分:1)
这是因为您在GetSize
方法中调用__init__()
- 在此方法完成之前,窗口未完全创建。因此,它的宽度和高度没有正确设置。
您可以使用wx.CallAfter / CallLater推迟调用此函数,直到窗口创建完全完成。