     }
 }
 
-// TODO: @implementation QMUIGhostButton (UIAppearance)
-
 /**
  *  用于 `QMUIFillButton.cornerRadius` 属性，当 `cornerRadius` 为 `QMUIFillButtonCornerRadiusAdjustsBounds` 时，`QMUIFillButton` 会在高度变化时自动调整 `cornerRadius`，使其始终保持为高度的 1/2。
  */
-let QMUIFillButtonCornerRadiusAdjustsBounds: CGFloat = -1
+fileprivate let QMUIFillButtonCornerRadiusAdjustsBounds: CGFloat = -1
 
 /**
  *  QMUIFillButton

        super.init(coder: aDecoder)
        self.ghostColor = GhostButtonColorBlue
    }

    private func updateImageColor() {
        imageView?.tintColor = adjustsImageWithGhostColor ? ghostColor : nil


extension QMUIGhostButton {
    
    public override static func appearance() -> QMUIGhostButton {
        
        return QMUIGhostButton(ghostType: .blue)
    }
    
    static func setDefaultAppearance() {
        let appearance = QMUIGhostButton.appearance()
        appearance.borderWidth = 1
        appearance.cornerRadius = QMUIGhostButtonCornerRadiusAdjustsBounds
