[UIBarButtonItem appearance] 设置BackBarButtonItem的图片

//返回按钮- (void)createBackBarButtonItem {//设置图片不被拉伸

//40为图片宽度    [[UIBarButtonItem appearance] setBackButtonBackgroundImage:[[UIImage imageNamed:@"backitem@2x"] resizableImageWithCapInsets:UIEdgeInsetsMake(0, 40, 0, 0)] forState:UIControlStateNormal barMetrics:UIBarMetricsDefault];//设置文字，水平偏移到看不见的位置    [[UIBarButtonItem appearance] setBackButtonTitlePositionAdjustment:UIOffsetMake(-500, 0) forBarMetrics:UIBarMetricsDefault];}