Python画在屏幕上

Question

我正在编写一个需要选择屏幕区域的应用程序.我需要将光标更改为十字形,然后在用户选择上绘制一个矩形.我搜索的第一件事是如何操纵光标,我遇到了wxPython.使用wxPython我可以轻松地在带有面板的Frame上执行此操作,问题是我需要窗口是透明的,这样用户可以在选择所需区域时看到他的屏幕,但是如果我制作框架和面板对象透明一切都变得越来越糟糕

所以,我对任何解决方案持开放态度,要么使用wxPython,要么不使用它,因为我真的不知道我是否正确使用它.

我是Python的新手,我不是英语母语人士,所以如果你不明白的话,我很抱歉.

这就是我编码的内容

import wx

class SelectableFrame(wx.Frame):

    c1 = None
    c2 = None

    def __init__(self, parent=None, id=-1, title=""):
        wx.Frame.__init__(self, parent, id, title, size=wx.DisplaySize(), style=wx.TRANSPARENT_WINDOW)

        self.panel = wx.Panel(self, size=self.GetSize(), style=wx.TRANSPARENT_WINDOW)

        self.panel.Bind(wx.EVT_MOTION, self.OnMouseMove)
        self.panel.Bind(wx.EVT_LEFT_DOWN, self.OnMouseDown)
        self.panel.Bind(wx.EVT_LEFT_UP, self.OnMouseUp)
        self.panel.Bind(wx.EVT_PAINT, self.OnPaint)

        self.SetCursor(wx.StockCursor(wx.CURSOR_CROSS))

    def OnMouseMove(self, event):
        if event.Dragging() and event.LeftIsDown():
            self.c2 = event.GetPosition()
            self.Refresh()

    def OnMouseDown(self, event):
        self.c1 = event.GetPosition()

    def OnMouseUp(self, event):
        self.SetCursor(wx.StockCursor(wx.CURSOR_ARROW))

    def OnPaint(self, event):
        if self.c1 is None or self.c2 is None: return

        dc = wx.PaintDC(self.panel)
        dc.SetPen(wx.Pen('red', 1))
        dc.SetBrush(wx.Brush(wx.Color(0, 0, 0), wx.TRANSPARENT))

        dc.DrawRectangle(self.c1.x, self.c1.y, self.c2.x - self.c1.x, self.c2.y - self.c1.y)

    def PrintPosition(self, pos):
        return str(pos.x) + " " + str(pos.y)


class MyApp(wx.App):

    def OnInit(self):
        frame = SelectableFrame()
        frame.Show(True)
        self.SetTopWindow(frame)

        return True



app = MyApp(0)
app.MainLoop()

Answer 1

您不应该在窗口创建中使用wx.TRANSPARENT,它主要用于wxDC绘制命令.要使窗口透明,只需调用win.SetTransparent(amount),其中amount为0-255,255表示不透明,0表示完全透明.见http://www.wxpython.org/docs/api/wx.Window-class.html#SetTransparent

我修改了你的代码,它只有在你的平台支持透明窗口时才有效,你可以通过CanSetTransparent检查它.我在Windows XP上测试过它.

import wx

class SelectableFrame(wx.Frame):

    c1 = None
    c2 = None

    def __init__(self, parent=None, id=-1, title=""):
        wx.Frame.__init__(self, parent, id, title, size=wx.DisplaySize())

        self.panel = wx.Panel(self, size=self.GetSize())

        self.panel.Bind(wx.EVT_MOTION, self.OnMouseMove)
        self.panel.Bind(wx.EVT_LEFT_DOWN, self.OnMouseDown)
        self.panel.Bind(wx.EVT_LEFT_UP, self.OnMouseUp)
        self.panel.Bind(wx.EVT_PAINT, self.OnPaint)

        self.SetCursor(wx.StockCursor(wx.CURSOR_CROSS))

        self.SetTransparent(50)

    def OnMouseMove(self, event):
        if event.Dragging() and event.LeftIsDown():
            self.c2 = event.GetPosition()
            self.Refresh()

    def OnMouseDown(self, event):
        self.c1 = event.GetPosition()

    def OnMouseUp(self, event):
        self.SetCursor(wx.StockCursor(wx.CURSOR_ARROW))

    def OnPaint(self, event):
        if self.c1 is None or self.c2 is None: return

        dc = wx.PaintDC(self.panel)
        dc.SetPen(wx.Pen('red', 1))
        dc.SetBrush(wx.Brush(wx.Color(0, 0, 0), wx.TRANSPARENT))

        dc.DrawRectangle(self.c1.x, self.c1.y, self.c2.x - self.c1.x, self.c2.y - self.c1.y)

    def PrintPosition(self, pos):
        return str(pos.x) + " " + str(pos.y)


class MyApp(wx.App):

    def OnInit(self):
        frame = SelectableFrame()
        frame.Show(True)
        self.SetTopWindow(frame)

        return True


app = MyApp(0)
app.MainLoop()