UIView背景颜色始终为白色

Question

我正在按钮操作上创建UIView：

-(IBAction)addSmiley{
    if(kSmiley == FALSE)
    {
        CGRect frame = CGRectMake(0, toolbar.frame.origin.y+50, 320, 50);
        viewSmiley = [[UIView alloc]initWithFrame:frame];
        [viewSmiley setBackgroundColor:[UIColor blackColor]];    
        [self.view addSubview:viewSmiley];
        tbl.frame = CGRectMake(tbl.frame.origin.x, 0, 320, tbl.frame.size.height-50);
        kSmiley = TRUE;
    }
    else
    {
        [viewSmiley removeFromSuperview];
        viewSmiley = nil;
        [viewSmiley release];
        tbl.frame = CGRectMake(0, 0, 320, tbl.frame.size.height+50);
        kSmiley = FALSE;
    }

}  

我能看到UIView但是有白色背景。我无法设置其背景颜色。可能是什么原因？

Answer 1

请参阅此https://developer.apple.com/library/ios/#documentation/WindowsViews/Conceptual/ViewPG_iPhoneOS/CreatingViews/CreatingViews.html

尝试在添加为子视图后更改视图的颜色。