wxpython - 调整图像大小而不闪烁？

Question

总的来说，我是 wxPython 和 GUI 的新手。现在应用程序只显示一个工具栏、状态栏和下面的面板。该面板包含一个带有 staticBitmap 的 boxSizer。每当调整窗口大小时，我都会尝试让图像自行调整大小以适合其容器，但我遇到了很多闪烁。

总结
调整窗口大小时调用 resizeImage()（EVT_SIZE 触发）
resizeImage() 调整面板大小以适应新尺寸，然后使用 scaleImage() 缩放图像并将其放置到 staticBitmap 中

resizeImage() 基本上是抓取图像对象，调整大小，设置为位图，然后设置为要显示的静态位图。

代码

class Canvas(wx.Panel):
"""Panel used to display selected images"""

#---------------------------------------------------------------------------
def __init__(self, parent):
    """Constructor"""
    wx.Panel.__init__(self, parent)

    # Globals
    self.image        = wx.EmptyImage(1,1)
    self.control    = wx.StaticBitmap(self, wx.ID_ANY, 
                                     wx.BitmapFromImage(self.image))    
    self.background    = wx.BLACK
    self.padding    = 5
    self.imageList    = []
    self.current    = 0
    self.total        = 0

    # Register Events
    Publisher().subscribe(self.onLoadDirectory, ("load directory"))
    Publisher().subscribe(self.resizeImage, ("resize window"))

    # Set Layout
    self.mainSizer = wx.BoxSizer(wx.VERTICAL)
    self.mainSizer.Add(self.control, 1, wx.ALL|wx.CENTER|wx.EXPAND,
            self.padding)
    self.SetSizer(self.mainSizer)
    self.SetBackgroundColour(self.background)

#---------------------------------------------------------------------------
def scaleImage(self, image, maxWidth, maxHeight):
    """asd"""
    width    = image.GetWidth()
    height    = image.GetHeight()
    ratio    = min( maxWidth / width, maxHeight/ height );
    image    = image.Scale(ratio*width, ratio*height, wx.IMAGE_QUALITY_HIGH)
    result    = wx.BitmapFromImage(image)

    return result

#---------------------------------------------------------------------------
def loadImage(self, image):
    """Load image"""
    self.image = wx.Image(image, wx.BITMAP_TYPE_ANY)
    bmp = wx.BitmapFromImage(self.image)
    w, h = self.mainSizer.GetSize()
    w = w - self.padding*2
    h = h - self.padding*2
    bmp = self.scaleImage(self.image, w, h)        
    self.control.SetBitmap(bmp)

#---------------------------------------------------------------------------
def getImageIndex(self, path):
    """Retrieve index of image from imagePaths"""
    i = 0
    for image in self.imagePaths:
        if image == path:
            return i
        i += 1
    return -1

#---------------------------------------------------------------------------
def resizeImage(self, event):
    self.SetSize(event.data)
    if self.total:
        w = event.data[0] - self.padding*2
        h = event.data[1] - self.padding*2
        bmp = self.scaleImage(self.image, w, h)
        self.control.SetBitmap(bmp)

#---------------------------------------------------------------------------
def onLoadDirectory(self, event):
    """Load the image and compile a list of image files from directory"""
    self.folderPath        = os.path.dirname(event.data)
    self.imagePaths        = glob.glob(self.folderPath + "\\*.jpg")
    self.total            = len(self.imagePaths)
    self.current        = self.getImageIndex(event.data)
    self.SetSize(self.GetSize())
    self.loadImage(self.imagePaths[self.current])

Answer 1

在double buffered DC 上尝试drawing，而不是使用 StaticBitmap。

Answer 2

在您的 resizeImage 方法中，添加 Freeze 和 Thaw 可能会有所帮助，如下所示：

def resizeImage(self, event):
    self.SetSize(event.data)
    if self.total:
        w = event.data[0] - self.padding*2
        h = event.data[1] - self.padding*2
        self.Freeze()
        bmp = self.scaleImage(self.image, w, h)
        self.control.SetBitmap(bmp)
        self.Thaw()