解决在自定义tabbar的时候出现双tabbar的问题

 最近有个项目需要自定义tabbar，

我自定义tabbar的一个思路就是完全取代系统自带的tabbar，生成一个继承自UIview的customTabbar，将生成的customTabbar完全覆盖到tabbar上，为了让我们自己生成的tabbar也能使用系统的一些方法，我们需要将customTabbar添加到系统的tabbar上，这就是我的一个大概思路(后期再添加自定义的相关逻辑和代码)

在自定义tabbar的时候出现的问题，在iOS7以后tabbar做了一些修改，如果我们将customTabbar直接添加到系统的tabbar后，我们会发现，在显示的时候出现我们自己的tabbar和系统的tabbar这种效果当然使我们不需要的，怎么解决呢？我提供一个我的思路：我的做法是将系统tabbar生成的UItabbarButton从他的父视图上面移除，

[objc]view plaincopy

for(UIView*button inself.tabBar.subviews) {

if([buttonisKindOfClass:[LXQTabBarclass]]) {

NSLog(@"button == %@",button);

}else{

[buttonremoveFromSuperview];

}

}

这样就完美解决了，但是在后期使用中又发现一个问题，当我们dismiss或则popToViewController的时候，还是会出现系统的tabbarbutton，什么原因呢？我也不清楚，我大概想到可能和view里面的layoutSubviews这个方法有关，（希望有大神能讲解一下这一块的东西，谢谢），但是tabbarController没有这个方法，只有viewwilllayoutsubviews和ViewWilldidlayoutsubsiews这两个方法，最后将删除系统tabbarbutton的方法添加到了ViewWillLayoutSubviews这个方法里面就解决了这个问题

后记：

在更新iOS 10以后又重新出现以前的情况，一时不知道该怎么去解决，后面想了想，一直在外部去修改还不如去内部修改，因此想到了runtime来解决这个问题，通过runtime去修改系统的方法下面列出代码：

一、打印UITabbar系统方法:

[objc]view plaincopy

- (void)systemMethod{

unsignedintcount;

NSMutableArray*array = [NSMutableArrayarray];

Method*meths = class_copyMethodList([UITabBarclass], &count);

for(inti =0; i < count; i ++) {

Method meth = meths[i];

SELsel = method_getName(meth);

constcharchar*name = sel_getName(sel);

NSString*str = [NSStringstringWithFormat:@"-------------- > %s",name];

[arrayaddObject:str];

}

LOG(@"%@",array);

}

打印的结果：

[objc]view plaincopy

(

"-------------- > remove_layoutSubviews",

"-------------- > setDelegate:",

"-------------- > layoutSubviews",

"-------------- > _populateArchivedSubviews:",

"-------------- > hitTest:withEvent:",

"-------------- > _intrinsicSizeWithinSize:",

"-------------- > _contentHuggingDefault_isUsuallyFixedHeight",

"-------------- > sizeThatFits:",

"-------------- > traitCollectionDidChange:",

"-------------- > _backgroundView",

"-------------- > setSemanticContentAttribute:",

"-------------- > setTranslatesAutoresizingMaskIntoConstraints:",

"-------------- > touchesBegan:withEvent:",

"-------------- > touchesMoved:withEvent:",

"-------------- > touchesEnded:withEvent:",

"-------------- > touchesCancelled:withEvent:",

"-------------- > _setVisualAltitude:",

"-------------- > _setVisualAltitudeBias:",

"-------------- > isTranslucent",

"-------------- > isLocked",

"-------------- > didUpdateFocusInContext:withAnimationCoordinator:",

"-------------- > preferredFocusedItem",

"-------------- > setTintColor:",

"-------------- > _isEligibleForFocus",

"-------------- > canBecomeFocused",

"-------------- > removeConstraint:",

"-------------- > addConstraint:",

"-------------- > _didMoveFromWindow:toWindow:",

"-------------- > hitTest:forEvent:",

"-------------- > _didChangeFromIdiom:onScreen:traverseHierarchy:",

"-------------- > _subclassImplementsDrawRect",

"-------------- > backgroundImage",

"-------------- > shadowImage",

"-------------- > setShadowImage:",

"-------------- > _appearanceStorage",

"-------------- > _accessibilityButtonShapesParametersDidChange",

"-------------- > _effectiveBarTintColor",

"-------------- > setItems:animated:",

"-------------- > setLocked:",

"-------------- > setBarStyle:",

"-------------- > _hidesShadow",

"-------------- > _backdropViewLayerGroupName",

"-------------- > _setBackdropViewLayerGroupName:",

"-------------- > _shadowView",

"-------------- > _setBackgroundView:",

"-------------- > _shadowAlpha",

"-------------- > _setShadowAlpha:",

"-------------- > _disableBlurTinting",

"-------------- > _setDisableBlurTinting:",

"-------------- > setBarTintColor:",

"-------------- > _setHidesShadow:",

"-------------- > barStyle",

"-------------- > setTranslucent:",

"-------------- > barTintColor",

"-------------- > _accessoryView",

"-------------- > _isTranslucent",

"-------------- > _setBarOrientation:",

"-------------- > _setAccessoryView:",

"-------------- > setSelectedItem:",

"-------------- > _setPreferredFocusHeading:",

"-------------- > _setFocusedItemHightlightShouldBeVisible:",

"-------------- > _setHiddenAwaitingFocus:",

"-------------- > beginCustomizingItems:",

"-------------- > isCustomizing",

"-------------- > setBackgroundImage:",

"-------------- > _sendAction:withEvent:",

"-------------- > _barMetrics",

"-------------- > _imageStyle",

"-------------- > _setBarMetrics:",

"-------------- > _setImageStyle:",

"-------------- > selectionIndicatorImage",

"-------------- > selectedImageTintColor",

"-------------- > _effectiveUnselectedTabTintColorConsideringView:",

"-------------- > _buttonDown:",

"-------------- > _buttonUp:",

"-------------- > _buttonCancel:",

"-------------- > _showsHighlightedState",

"-------------- > _setShowsHighlightedState:",

"-------------- > _scrollsItems",

"-------------- > itemPositioning",

"-------------- > itemWidth",

"-------------- > itemSpacing",

"-------------- > _configureItems:",

"-------------- > _setBackgroundNeedsUpdate:",

"-------------- > _blurEnabled",

"-------------- > _preferredFocusHeading",

"-------------- > selectedItem",

"-------------- > _focusedItemHighlightShouldBeVisible",

"-------------- > _setBlurEnabled:",

"-------------- > setSelectionIndicatorImage:",

"-------------- > setSelectedImageTintColor:",

"-------------- > _configureTabBarReplacingItem:withNewItem:swapping:",

"-------------- > _positionAllItems",

"-------------- > setItemWidth:",

"-------------- > setItemSpacing:",

"-------------- > _setScrollsItems:",

"-------------- > setItemPositioning:",

"-------------- > _accessibilityButtonShapesEnabledDidChangeNotification:",

"-------------- > setUnselectedItemTintColor:",

"-------------- > _doCommonTabBarInit",

"-------------- > _effectiveBarOrientation",

"-------------- > _updateBackgroundColorForTraitCollection:",

"-------------- > _customizeWithAvailableItems:",

"-------------- > _dismissCustomizeSheet:",

"-------------- > _updateTintedImages:selected:",

"-------------- > _effectiveBarTintColorDidChange",

"-------------- > unselectedItemTintColor",

"-------------- > _effectiveUnselectedTintColor",

"-------------- > _isHiddenAwaitingFocus",

"-------------- > _buttonDownDelayed:",

"-------------- > _adjustButtonSelection:",

"-------------- > _customizeDoneButtonAction:",

"-------------- > _totalDimensionForItems:spacing:dimension:scaleFactor:",

"-------------- > _setBackgroundImage:",

"-------------- > _setSelectionIndicatorImage:",

"-------------- > _setLabelFont:",

"-------------- > _setLabelTextColor:selectedTextColor:",

"-------------- > _setLabelShadowColor:",

"-------------- > _setLabelShadowOffset:",

"-------------- > _setVibrantLabels:",

"-------------- > _vibrantLabels",

"-------------- > _nextSelectionSlideDuration",

"-------------- > _setNextSelectionSlideDuration:",

"-------------- > _backgroundNeedsUpdate",

"-------------- > _setTabBarSizing:",

"-------------- > _setTabButtonWidth:",

"-------------- > _tabButtonWidth",

"-------------- > _setInterTabButtonSpacing:",

"-------------- > _interTabButtonSpacing",

"-------------- > _barOrientation",

"-------------- > endCustomizingAnimated:",

"-------------- > _makeCurrentButtonFirstResponder",

"-------------- > _setDividerImage:forLeftButtonState:rightButtonState:",

"-------------- > _dividerImageForLeftButtonState:rightButtonState:",

"-------------- > _pendingFocusAction",

"-------------- > _setPendingFocusAction:",

"-------------- > _focusedTabBarItem",

"-------------- > _tabBarFinishedAnimating",

"-------------- > dismissCustomizeSheet:",

"-------------- > _scaleFactorForItems:spacing:dimension:maxWidth:",

"-------------- > _updateTabBarItemView:",

"-------------- > _tabBarSizing",

"-------------- > isElementAccessibilityExposedToInterfaceBuilder",

"-------------- > _autolayoutSpacingAtEdge:inContainer:",

"-------------- > _autolayoutSpacingAtEdge:nextToNeighbor:",

"-------------- > _hasCustomAutolayoutNeighborSpacing",

"-------------- > encodeWithCoder:",

"-------------- > initWithCoder:",

"-------------- > delegate",

"-------------- > setBounds:",

"-------------- > .cxx_destruct",

"-------------- > dealloc",

"-------------- > initWithFrame:",

"-------------- > setFrame:",

"-------------- > items",

"-------------- > setItems:",

"-------------- > drawRect:"

)

我接触iOS的时间也不长，不能从这对堆结果中去找到具体设置tabbarbutton的方法，但是我知道layoutSubviews是布局子视图的方法，然后就用runtime替换掉UItabbar中的layoutSubviews方法，在布局子视图的时候将系统自带的UItabbarbutton给移除掉，贴代码:

这段代码是写在UItabbar的分类中的:

[objc]view plaincopy

+ (void)load{

staticdispatch_once_t onceToken;

dispatch_once(&onceToken, ^{

SELsystemSel =@selector(layoutSubviews);

SELlxqSel =@selector(remove_layoutSubviews);

Method systemMethod = class_getInstanceMethod([selfclass], systemSel);

Method lxqMethod = class_getInstanceMethod([selfclass], lxqSel);

BOOLisAdd = class_addMethod(self, systemSel, method_getImplementation(lxqMethod), method_getTypeEncoding(lxqMethod));

if(isAdd) {

class_replaceMethod(self, lxqSel, method_getImplementation(systemMethod), method_getTypeEncoding(systemMethod));

}else{

method_exchangeImplementations(systemMethod, lxqMethod);

}

});

}

- (void)remove_layoutSubviews{

NSArray*subviews =self.subviews;

for(UIView*subview in subviews) {

if([subviewisKindOfClass:[LXQTabBarclass]]) {

}else{

[subviewremoveFromSuperview];

}

}

}

这样就完美解决了iOS10 以及以前系统的问题了，不过就是不知道这样做了之后会不会出现审核不通过的问题！

原文链接 :http://blog.csdn.net/lixingqiao01/article/details/51819358