1虹蒋、導(dǎo)航欄返回按鈕無文字設(shè)置：
用的下面方法設(shè)置的導(dǎo)致按鈕向下偏移的
[[UIBarButtonItem appearance] setBackButtonTitlePositionAdjustment:UIOffsetMake(0,-60) forBarMetrics:UIBarMetricsDefault];
解決辦法：
[[UIBarButtonItem appearance] setBackButtonTitlePositionAdjustment:UIOffsetMake(-200, 0) forBarMetrics:UIBarMetricsDefault];
2房午、使用tableView時(shí)汰聋，狀態(tài)欄空出20像素
解決辦法：
self.extendedLayoutIncludesOpaqueBars = YES;
if (@available(iOS 11.0, *)) {
self.tableView.contentInsetAdjustmentBehavior = UIScrollViewContentInsetAdjustmentNever;
} else {
self.automaticallyAdjustsScrollViewInsets = NO;
}
3帘营、自定義導(dǎo)航欄返回按鈕，UIBarButtonSystemItemFixedSpace失效
解決辦法：
UIBarButtonItem *leftItem = [[UIBarButtonItem alloc]initWithImage:[UIImage imageNamed:@"back"] style:UIBarButtonItemStyleDone target:self action:@selector(backBtnClick)];
if (@available(ios 11.0,*)) {
leftItem.imageInsets = UIEdgeInsetsMake(0, -10, 0, 0);
self.navigationItem.leftBarButtonItem = leftItem;
} else {
UIBarButtonItem *negativeSpacer = [[UIBarButtonItem alloc]initWithBarButtonSystemItem:UIBarButtonSystemItemFixedSpace target:nil action:nil];
negativeSpacer.width = -10;
self.navigationItem.leftBarButtonItems = [NSArray arrayWithObjects:negativeSpacer, leftItem, nil];
}
