获取extension，判断第一次

CustomKeyboard/View/KBToolBar.m

@@ -9,12 +9,13 @@
 
 @implementation KBToolBar
 
-/*
-// Only override drawRect: if you perform custom drawing.
-// An empty implementation adversely affects performance during animation.
-- (void)drawRect:(CGRect)rect {
-    // Drawing code
+- (instancetype)initWithFrame:(CGRect)frame{
+    if (self = [super initWithFrame:frame]) {
+        
+    }
+    return self;
 }
-*/
+
+
 
 @end