我正在尝试从 wxPython 示例中修改 DragImage 演示，以便拖动图像会产生一个可拖动的新副本，而不是仅仅移动图像，而保留原始的“源”图像。一个不错的类比是原始图像就像一组可供选择的小部件；单击并拖动其中任何一个都会生成一个小部件，您可以将其放置在任何地方（这可以多次完成），而源小部件仍然存在。
import os
import glob
import wx
import wx.lib.scrolledpanel as scrolled
class MainWindow(wx.Frame):
def __init__(self, parent, title):
wx.Frame.__init__(self, parent)
frm_pnl = MainPanel(self)
self.Show()
class DragShape:
def __init__(self, bmp):
self.bmp = bmp
self.pos = (0,0)
self.shown = True
self.text = None
self.fullscreen = False
def HitTest(self, pt):
rect = self.GetRect()
return rect.InsideXY(pt.x, pt.y)
def GetRect(self):
#return wx.Rect(self.pos[0], self.pos[1], self.bmp.GetWidth(), self.bmp.GetHeight())
return wx.Rect(self.pos[0], self.pos[1], self.bmp.GetWidth()/2, self.bmp.GetHeight()/2)
def Draw(self, dc, op = wx.COPY):
if self.bmp.Ok():
memDC = wx.MemoryDC()
memDC.SelectObject(self.bmp)
#dc.Blit(self.pos[0], self.pos[1],
# self.bmp.GetWidth(), self.bmp.GetHeight(),
# memDC, 0, 0, op, True)
dc.Blit(self.pos[0], self.pos[1],
self.bmp.GetWidth()/2, self.bmp.GetHeight()/2,
memDC, 0, 0, op, True)
return True
else:
return False
class MainPanel(wx.Panel):
def __init__(self, parent):
wx.Panel.__init__(self, parent, -1, size = (900, 700))
self.shapes = []
#panel for mechanisms
mechPnl = MechanismPanel(self)
mechSzr = wx.BoxSizer(wx.HORIZONTAL)
mechSzr.Add(mechPnl, 1)
selfSizer = wx.BoxSizer(wx.VERTICAL)
selfSizer.Add(mechSzr, 0, wx.EXPAND)
selfSizer.Layout()
self.SetSizer(selfSizer)
self.dragImage = None
self.dragShape = None
self.hiliteShape = None
self.SetCursor(wx.StockCursor(wx.CURSOR_ARROW))
#self.Bind(wx.EVT_ERASE_BACKGROUND, self.OnEraseBackground)
self.Bind(wx.EVT_PAINT, self.OnPaint)
mechPnl.Bind(wx.EVT_LEFT_DOWN, self.OnLeftDown)
mechPnl.Bind(wx.EVT_LEFT_UP, self.OnLeftUp)
mechPnl.Bind(wx.EVT_MOTION, self.OnMotion)
mechPnl.Bind(wx.EVT_LEAVE_WINDOW, self.OnLeaveWindow)
# The mouse is moving
def OnMotion(self, evt):
print "On motion!"
# Ignore mouse movement if we're not dragging.
if not self.dragShape or not evt.Dragging() or not evt.LeftIsDown():
return
# if we have a shape, but haven't started dragging yet
if self.dragShape and not self.dragImage:
# only start the drag after having moved a couple pixels
tolerance = 2
pt = evt.GetPosition()
dx = abs(pt.x - self.dragStartPos.x)
dy = abs(pt.y - self.dragStartPos.y)
if dx <= tolerance and dy <= tolerance:
return
# refresh the area of the window where the shape was so it
# will get erased.
self.dragShape.shown = False
self.RefreshRect(self.dragShape.GetRect(), True)
self.Update()
if self.dragShape.text:
self.dragImage = wx.DragString(self.dragShape.text,
wx.StockCursor(wx.CURSOR_HAND))
else:
self.dragImage = wx.DragImage(self.dragShape.bmp,
wx.StockCursor(wx.CURSOR_HAND))
hotspot = self.dragStartPos - self.dragShape.pos
self.dragImage.BeginDrag(hotspot, self, self.dragShape.fullscreen)
self.dragImage.Move(pt)
self.dragImage.Show()
# if we have shape and image then move it, posibly highlighting another shape.
elif self.dragShape and self.dragImage:
onShape = self.FindShape(evt.GetPosition())
unhiliteOld = False
hiliteNew = False
# figure out what to hilite and what to unhilite
if self.hiliteShape:
if onShape is None or self.hiliteShape is not onShape:
unhiliteOld = True
if onShape and onShape is not self.hiliteShape and onShape.shown:
hiliteNew = True
# if needed, hide the drag image so we can update the window
if unhiliteOld or hiliteNew:
self.dragImage.Hide()
if unhiliteOld:
dc = wx.ClientDC(self)
self.hiliteShape.Draw(dc)
self.hiliteShape = None
if hiliteNew:
dc = wx.ClientDC(self)
self.hiliteShape = onShape
self.hiliteShape.Draw(dc, wx.INVERT)
# now move it and show it again if needed
self.dragImage.Move(evt.GetPosition())
if unhiliteOld or hiliteNew:
self.dragImage.Show()
# Left mouse button up.
def OnLeftUp(self, evt):
print "On left up!"
if not self.dragImage or not self.dragShape:
self.dragImage = None
self.dragShape = None
return
# Hide the image, end dragging, and nuke out the drag image.
self.dragImage.Hide()
self.dragImage.EndDrag()
self.dragImage = None
if self.hiliteShape:
self.RefreshRect(self.hiliteShape.GetRect())
self.hiliteShape = None
# reposition and draw the shape
# Note by jmg 11/28/03
# Here's the original:
#
# self.dragShape.pos = self.dragShape.pos + evt.GetPosition() - self.dragStartPos
#
# So if there are any problems associated with this, use that as
# a starting place in your investigation. I've tried to simulate the
# wx.Point __add__ method here -- it won't work for tuples as we
# have now from the various methods
#
# There must be a better way to do this :-)
#
self.dragShape.pos = (
self.dragShape.pos[0] + evt.GetPosition()[0] - self.dragStartPos[0],
self.dragShape.pos[1] + evt.GetPosition()[1] - self.dragStartPos[1]
)
self.dragShape.shown = True
self.RefreshRect(self.dragShape.GetRect())
self.dragShape = None
# Fired whenever a paint event occurs
def OnPaint(self, evt):
print "On paint!"
dc = wx.PaintDC(self)
self.PrepareDC(dc)
self.DrawShapes(dc)
# Left mouse button is down.
def OnLeftDown(self, evt):
print "On left down!"
# Did the mouse go down on one of our shapes?
shape = self.FindShape(evt.GetPosition())
# If a shape was 'hit', then set that as the shape we're going to
# drag around. Get our start position. Dragging has not yet started.
# That will happen once the mouse moves, OR the mouse is released.
if shape:
self.dragShape = shape
self.dragStartPos = evt.GetPosition()
# Go through our list of shapes and draw them in whatever place they are.
def DrawShapes(self, dc):
for shape in self.shapes:
if shape.shown:
shape.Draw(dc)
# This is actually a sophisticated 'hit test', but in this
# case we're also determining which shape, if any, was 'hit'.
def FindShape(self, pt):
for shape in self.shapes:
if shape.HitTest(pt):
return shape
return None
# Clears the background, then redraws it. If the DC is passed, then
# we only do so in the area so designated. Otherwise, it's the whole thing.
def OnEraseBackground(self, evt):
dc = evt.GetDC()
if not dc:
dc = wx.ClientDC(self)
rect = self.GetUpdateRegion().GetBox()
dc.SetClippingRect(rect)
self.TileBackground(dc)
# tile the background bitmap
def TileBackground(self, dc):
sz = self.GetClientSize()
w = self.bg_bmp.GetWidth()
h = self.bg_bmp.GetHeight()
x = 0
while x < sz.width:
y = 0
while y < sz.height:
dc.DrawBitmap(self.bg_bmp, x, y)
y = y + h
x = x + w
# We're not doing anything here, but you might have reason to.
# for example, if you were dragging something, you might elect to
# 'drop it' when the cursor left the window.
def OnLeaveWindow(self, evt):
pass
class MechanismPanel(scrolled.ScrolledPanel):
def __init__(self, parent):
scrolled.ScrolledPanel.__init__(self, parent, -1, size = (400, 140))
self.SetBackgroundColour((211, 211, 211))
mechPnlSzr = wx.BoxSizer(wx.HORIZONTAL)
os.chdir("./figures")
position = 50
for file in glob.glob("icon*.png"):
print file
imgIcon = wx.Image(file, wx.BITMAP_TYPE_PNG).ConvertToBitmap()
staticBitmap = wx.StaticBitmap(self, -1, imgIcon, (position, 50), (50, 50))
shape = DragShape(staticBitmap.GetBitmap())
shape.pos = (position, 50)
position = position + 100
shape.fullscreen = True
parent.shapes.append(shape)
mechPnlSzr.Add(staticBitmap, 0, wx.FIXED, border = 20)
self.SetSizer(mechPnlSzr)
self.SetAutoLayout(1)
self.SetupScrolling()#scroll_y = False)
app = wx.App(False)
frame = MainWindow(None, "Trading Client")
app.MainLoop()