python - 更改 Canvas ScaledText 的背景颜色

Question

我正在使用wxPython Canvas ' AddScaledTextBox(...) 创建缩放文本框。

参见here例如:

Box = Canvas.AddScaledTextBox("A Two Line\nString",
                                  Point,
                                  2,
                                  BackgroundColor = "Yellow",
                                  LineColor = "Red",
                                  LineStyle = "Solid",
                                  PadSize = 5,
                                  Family = wx.TELETYPE,
                                  Position = 'bl')

定义文本框后如何更改背景颜色？(例如用户输入 => 背景颜色更改)

Answer 1

很确定这是一个错误。请参阅lines 1841 - 1845 in the wxPython source - 有一个对 self.BackgroundColor 的引用，但从未使用过。

因此，对于您的示例，您需要设置与文本框关联的画笔的颜色。我根据 Robin Dunn 的示例编写了以下内容。函数SetBoxBackground是重要的部分。

如评论中所述，仅调用 box.Brush.SetColour(color) 或 box.Pen.SetColour(color) 可能会导致问题:如果您有两个具有相同颜色的文本框，更改其中一个的画笔/笔颜色也会影响另一个。 (我不是 100% 确定，但我认为这是因为缓存，例如参见 this comment in the source 。)

import wx
from wx.lib.floatcanvas import FloatCanvas

class TestFrame(wx.Frame):
    def __init__(self, *args, **kwargs):
        wx.Frame.__init__(self, *args, **kwargs)
        self.canvas = FloatCanvas.FloatCanvas(self, BackgroundColor = "black")
        MainSizer = wx.BoxSizer(wx.VERTICAL)
        MainSizer.Add(self.canvas, 4, wx.EXPAND)
        self.SetSizer(MainSizer)
        self.box = self.canvas.AddScaledTextBox("A Two Line\nString",
                                  (0,10),
                                  2,
                                  BackgroundColor = "Yellow",
                                  LineColor = "Red",
                                  LineStyle = "Solid",
                                  PadSize = 5,
                                  Family = wx.TELETYPE,
                                  Position = 'bl')
        self.box2 = self.canvas.AddScaledTextBox("Second Box",
                                  (0,0),
                                  2,
                                  BackgroundColor = "Yellow",
                                  LineColor = "Red",
                                  LineStyle = "Solid",
                                  PadSize = 5,
                                  Family = wx.TELETYPE,
                                  Position = 'bl')
        self.box.Bind(FloatCanvas.EVT_FC_LEFT_DOWN, self.OnRectDown)
        wx.CallAfter(self.canvas.ZoomToBB)

    def OnRectDown(self, event):
        print ('Rectangle: Left Button down clicked at:', event.HitCoords)
        if self.box.Color == 'red':
            self.SetBoxBackground('green', "Solid")
            self.box.SetColor('black')
        else:
            self.SetBoxBackground('white', "Solid")
            self.box.SetColor('red')
        self.canvas.ClearBackground()
        self.canvas.Refresh()
        self.canvas.Draw(True)

    def SetBoxBackground(self, color, style, linewidth=1):
        # See https://github.com/wxWidgets/wxPython/blob/master/wx/lib/floatcanvas/FloatCanvas.py#L1841

        # Create a new brush (fill) with specified color
        self.box.SetBrush(color, style)
        # Create a new pen (line) with specified color
        self.box.SetPen(color, style, linewidth)
        self.box.SetBackgroundColor(color) # Now this works correctly

app = wx.App(0)
frame = TestFrame(None, title="Test")
frame.Show(True)
app.MainLoop()