Ios setBackButtonBackgroundImage时应用程序崩溃

我正在尝试使用以下代码全局设置UINavigationBar的外观：

[[UINavigationBar appearance] setBarStyle:UIBarStyleBlack];
[[UINavigationBar appearance] setBackgroundImage:[UIImage imageNamed:@"bg_daohang"] forBarMetrics:UIBarMetricsDefault];
[[UINavigationBar appearance] setBackButtonBackgroundImage:[UIImage imageNamed:@"btn_fanhui_1"] forState:UIControlStateNormal barMetrics:UIBarMetricsDefault];

我已经成功地设置了barStyle和backGroundImage，但是当我设置backButtonBack（第三行）的外观时。应用程序崩溃，我得到如下错误：

Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[_UIAppearance     setBackButtonBackgroundImage:forState:barMetrics:]: unrecognized selector sent to instance 0x1dd7ea00'

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如何全局正确设置backButtonBack的外观？

setBackButtonTitlePositionAdjustment:forBarMetrics:

属于

UIBarButtonItem

使用：

[[UIBarButtonItem appearance] setBackButtonBackgroundImage:[UIImage imageNamed:@"btn_fanhui_1"] forState:UIControlStateNormal barMetrics:UIBarMetricsDefault];