iOS开发系列之常用框架开发集—自定义UINavitationController开发1

在实际开发过程中构建我们项目框架时为了用户体验好和个性化往往需要手势返回的功能，虽然ios7以后的系统支持这个但是系统有些不足如：支持手势返回需要ios7.0以上系统，手势非要从左边缘开始拉，触摸拉开效果不能自定义，然而我们今天就给大家开发一款支持手势返回没有系统要求（ios5.0以上），从哪里可以触摸返回可以自定义的一个导航框架。
我这个是以淘宝app的导航框架为例开发。
WHC_NavigationController.h头文件如下：

//
//  WHC_NavigationController.h
//  WHC_NavigationController
//
//  Created by 吴海超 on 15/4/13.
//  Copyright (c) 2015年 吴海超. All rights reserved.
//

#import <UIKit/UIKit.h>
#define KWHC_Nav_Main_VC_Name (@"MyTabBarVC")     //主控制器类名
#define KWHC_Nav_Touch_Back_Rate (0.4)            //触摸拖拽可以返回条件比例
#define KWHC_Nav_Pop_Form_Border (-1)             //note > 0 from border pull < 0 any where pull diatancex > 30
@interface WHC_NavigationController : UINavigationController

//单例默认用KWHC_Nav_Main_VC_Name作为主控制器
+ (instancetype)sharedInstance;

//单例自定义主控制器
+ (instancetype)sharedInstanceWithMainVC:(UIViewController*)mainVC;
@end

WHC_NavigationController.m源文件如下：

//
//  WHC_NavigationController.m
//  SideMenu
//
//  Created by 吴海超 on 15/4/13.
//  Copyright (c) 2015年 吴海超. All rights reserved.
//

#import "WHC_NavigationController.h"
#define KWHC_NAV_LEFT_VIEW_TAG (203994850)                         //左边view的tag
#define KWHC_NAV_LEFT_PUSH_VIEW_TAG (KWHC_NAV_LEFT_VIEW_TAG + 1)   //左边pushView的tag
#define KWHC_NAV_NAVBAR_TAG (KWHC_NAV_LEFT_VIEW_TAG + 2)           //导航条的tag
#define KWHC_NAV_ANIMATION_DURING (0.3)                            //pop或者push动画周期
#define KWHC_NAV_POP_VIEW_CENTERX_OFFSET (0)                       //popView中心x轴偏移 （禁止修改值）
#define KWHC_NAV_PUSH_VIEW_CENTERX_OFFSET (0)                      //pushView中心x偏移  (禁止修改值)
#define KWHC_NAV_POP_VIEW_ALPHA (0.5)                              //popview透明系数
#define KWHC_NAV_ALLOW_PULL_DISTANCE (30.0)                        //可以拉开允许的距离
@interface WHC_NavigationController ()<UINavigationControllerDelegate>{
    UIPanGestureRecognizer           *   _panGesture;              //手势
    CGFloat                              _currentTx;               //存储当前触摸x值

    NSMutableArray                   *   _snapshootList;           //快照数组
    UIView                           *   _popView;                 //弹出view
    UIView                           *   _pushView;                //压站view
    UIView                           *   _topView;                 //顶部视图
    BOOL                                 _willOpen;                //是否将要拉开
    BOOL                                 _didOpen;                 //是否已经拉开
    BOOL                                 _isTouchPop;              //是否触摸弹出
}

@end

static WHC_NavigationController * whc_navigation;

@implementation WHC_NavigationController

//单例实现
+ (instancetype)sharedInstance{
    UIViewController  * rootVC = [[NSClassFromString(KWHC_Nav_Main_VC_Name) alloc]init];
    //        UIViewController  * rootVC = [[NSClassFromString(KWHC_Side_Menu_N_Main_VC_Name) alloc]initWithNibName:KWHC_Nav_Main_VC_Name bundle:nil];
    return [WHC_NavigationController sharedInstanceWithMainVC:rootVC];
}

+ (instancetype)sharedInstanceWithMainVC:(UIViewController*)mainVC{
    static dispatch_once_t predicate;
    dispatch_once(&predicate, ^{
        whc_navigation = [[WHC_NavigationController alloc]initWithRootViewController:mainVC];
        whc_navigation.delegate = whc_navigation;
    });
    return whc_navigation;
}
#pragma mark - initMothed

//重载父类初始化方法
- (instancetype)initWithRootViewController:(UIViewController *)rootViewController{
    self = [super initWithRootViewController:rootViewController];
    if(self){
        [self registPanGesture:YES];
    }
    return self;
}

- (instancetype)initWithCoder:(NSCoder *)aDecoder{
    self = [super initWithCoder:aDecoder];
    if(self != nil){
        [self registPanGesture:YES];
    }
    return self;
}

- (instancetype)init{
    self = [super init];
    if(self != nil){
        [self registPanGesture:YES];
    }
    return self;
}

- (instancetype)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil{
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
    if(self){
        [self registPanGesture:YES];
    }
    return self;
}
#pragma mark - gestureMothed
//注册手势事件
- (void)registPanGesture:(BOOL)b{
    self.interactivePopGestureRecognizer.enabled = NO;
    if(b){
        if(_panGesture == nil){
            _panGesture = [[UIPanGestureRecognizer alloc]initWithTarget:self action:@selector(handlePanGesture:)];
            [_panGesture delaysTouchesBegan];
            [self.view addGestureRecognizer:_panGesture];
        }
    }else{
        if(_panGesture != nil){
            [self.view removeGestureRecognizer:_panGesture];
            _panGesture = nil;
        }
    }
}

#pragma mark - handleGesture
- (void)handlePanGesture:(UIPanGestureRecognizer*)panGesture{

    switch (panGesture.state) {
        case UIGestureRecognizerStateBegan:{
            _currentTx = self.view.transform.tx;
        }
            break;
        case UIGestureRecognizerStateChanged:{
            CGFloat  moveDistance = [panGesture translationInView:panGesture.view].x;
            if(!_willOpen){
                if(KWHC_Nav_Pop_Form_Border < (0)){
                    if(moveDistance < KWHC_NAV_ALLOW_PULL_DISTANCE){
                        return;
                    }
                }else{
                    CGFloat touchX = [panGesture locationInView:panGesture.view].x;
                    if(touchX > KWHC_Nav_Pop_Form_Border){
                        return;
                    }
                }
            }
            CGFloat  oriX = [panGesture velocityInView:panGesture.view].x;
            CGFloat  rate = moveDistance / CGRectGetWidth(self.view.frame);
            if(oriX > 0){//open door
                [self popView];
                if(!_willOpen && _popView != nil){

                    UIView * oldPopView = [self.view.superview viewWithTag:KWHC_NAV_LEFT_VIEW_TAG];
                    if(oldPopView){
                        [oldPopView removeFromSuperview];
                    }
                    [self.view.superview insertSubview:_popView belowSubview:self.view];
                    _willOpen = YES;

                }
                if(_willOpen && moveDistance >= 0.0){

                    self.view.transform = [self initAffineTransform:moveDistance + _currentTx];
                    _popView.center = CGPointMake(KWHC_NAV_POP_VIEW_CENTERX_OFFSET + rate * CGRectGetWidth(_popView.frame) / 2.0, _popView.center.y);
                    _popView.alpha = KWHC_NAV_POP_VIEW_ALPHA * (rate + 1.0);

                }

            }else if(oriX < 0 && _willOpen && moveDistance >= 0.0){//close door

                self.view.transform = [self initAffineTransform:moveDistance + _currentTx];
                _popView.center = CGPointMake(KWHC_NAV_POP_VIEW_CENTERX_OFFSET + rate * CGRectGetWidth(_popView.frame) / 2.0, _popView.center.y);
                _popView.alpha = KWHC_NAV_POP_VIEW_ALPHA * (rate + 1.0);

            }else if(_willOpen){

                if(moveDistance < 0.0 && self.view.transform.tx > 0){
                    self.view.transform = [self initAffineTransform:0.0];
                    _popView.center = CGPointMake(KWHC_NAV_POP_VIEW_CENTERX_OFFSET, _popView.center.y);
                    _popView.alpha = KWHC_NAV_POP_VIEW_ALPHA;
                }
            }
        }
            break;
        case UIGestureRecognizerStateCancelled:
        case UIGestureRecognizerStateEnded:{
            if(_willOpen){
                if(self.view.transform.tx / CGRectGetWidth(self.view.frame) < KWHC_Nav_Touch_Back_Rate){
                    [self closeLeftView:YES];
                }else{
                    [self closeLeftView:NO];
                }
            }
        }
            break;
        default:
            break;
    }
}

//偏移变换
- (CGAffineTransform)initAffineTransform:(CGFloat)x{
    return  CGAffineTransformMakeTranslation(x, 0.0);
}

//对当前控制器进行快照
- (UIImage*)snapshootNavBar:(UIViewController*)vc{

    UIGraphicsBeginImageContextWithOptions(self.view.frame.size, self.view.opaque, 0.0);
    [self.view.layer renderInContext:UIGraphicsGetCurrentContext()];
    UIImage  * snapshootImage = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    return snapshootImage;
}

//获取要弹出view的快照view
- (UIView*)popView{
    if(_snapshootList != nil && _snapshootList.count > 1){
        _popView = [_snapshootList lastObject];
        _popView.center = CGPointMake(KWHC_NAV_POP_VIEW_CENTERX_OFFSET, _popView.center.y);
        _popView.alpha = KWHC_NAV_POP_VIEW_ALPHA;
    }else{
        _popView = nil;
    }
    return _popView;
}

//获取已经push的快照view
- (UIView*)pushView{
    if(_snapshootList != nil && _snapshootList.count > 0){
        _pushView = [_snapshootList lastObject];
        _pushView.center = CGPointMake(KWHC_NAV_PUSH_VIEW_CENTERX_OFFSET, _pushView.center.y);
        _pushView.alpha = 1.0;
    }else{
        _pushView = nil;
    }
    return _pushView;
}

//pop或者取消pop操作
- (void)closeLeftView:(BOOL)isClose{
    [self registPanGesture:NO];
    _willOpen = NO;
    UIView * mainView = self.view;
    __weak  typeof(self) sf = self;
    if(isClose){
        [UIView animateWithDuration:KWHC_NAV_ANIMATION_DURING delay:0 options:UIViewAnimationOptionCurveEaseOut animations:^{
            _popView.center = CGPointMake(KWHC_NAV_POP_VIEW_CENTERX_OFFSET, _popView.center.y);
            _popView.alpha = KWHC_NAV_POP_VIEW_ALPHA;
            mainView.transform = [sf initAffineTransform:0.0];
        } completion:^(BOOL finished) {
            [sf registPanGesture:YES];
            [_popView  removeFromSuperview];
            _popView = nil;
        }];
    }else{//pop opeartion
        [UIView animateWithDuration:KWHC_NAV_ANIMATION_DURING delay:0 options:UIViewAnimationOptionCurveEaseOut animations:^{
            mainView.transform = [sf initAffineTransform:CGRectGetWidth(mainView.frame)];
            _popView.center = CGPointMake(CGRectGetWidth(_popView.frame) / 2.0, _popView.center.y);
            _popView.alpha = 1.0;
        } completion:^(BOOL finished) {
            [sf registPanGesture:YES];
            _isTouchPop = YES;
            mainView.transform = [sf initAffineTransform:0];
            [sf popViewControllerAnimated:NO];
        }];
    }
}

#pragma mark - viewLoad
- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view.
}

- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

//重载父类push方法
- (void)pushViewController:(UIViewController *)viewController animated:(BOOL)animated{
    if(_snapshootList == nil){
        _snapshootList = [NSMutableArray array];
    }
    [_snapshootList addObject:[[UIImageView alloc]initWithImage:[self snapshootNavBar:viewController]]];
    [self pushView];
    //忽略第一次push操作
    if(_pushView && animated && _snapshootList != nil){

        __weak  typeof(self) sf = self;
        //防止重复push
        _topView = self.topViewController.view;
        _topView.userInteractionEnabled = NO;
        [super pushViewController:viewController animated:NO];
        self.view.transform = [self initAffineTransform:CGRectGetWidth(self.view.frame)];
        UIView * oldPushView = [self.view.superview viewWithTag:KWHC_NAV_LEFT_PUSH_VIEW_TAG];
        if(oldPushView){
            [oldPushView removeFromSuperview];
            oldPushView = nil;
        }
        _pushView.center = CGPointMake(CGRectGetWidth(_pushView.frame) / 2.0, _pushView.center.y);
        [self.view.superview insertSubview:_pushView belowSubview:self.view];
        [UIView animateWithDuration:KWHC_NAV_ANIMATION_DURING delay:0 options:UIViewAnimationOptionCurveEaseIn animations:^{
            _pushView.center = CGPointMake(-CGRectGetWidth(_pushView.frame) / 2.0, _pushView.center.y);
            _pushView.alpha = KWHC_NAV_POP_VIEW_ALPHA;
            sf.view.transform = [sf initAffineTransform:0];
        } completion:^(BOOL finished) {
            [_pushView removeFromSuperview];
            _pushView = nil;
        }];

    }else{

        [super pushViewController:viewController animated:animated];
    }
}

//重写父类pop方法
- (UIViewController *)popViewControllerAnimated:(BOOL)animated{
    UIViewController  * viewController = nil;
    if(!_isTouchPop){
        //不是触摸弹出操作
        __weak  typeof(self) sf = self;
        __block UIView  * popView = [[UIImageView alloc]initWithImage:[self snapshootNavBar:nil]];
        viewController = [super popViewControllerAnimated:NO];
        if(popView){
            self.view.transform = [self initAffineTransform:-CGRectGetWidth(self.view.frame)];
            self.view.alpha = KWHC_NAV_POP_VIEW_ALPHA;
            UIView  * oldPopView = [self.view.superview viewWithTag:KWHC_NAV_LEFT_VIEW_TAG];
            if(oldPopView){
                [oldPopView removeFromSuperview];
                oldPopView = nil;
            }
            popView.center = CGPointMake(CGRectGetWidth(popView.frame) / 2.0, popView.center.y);
            [self.view.superview insertSubview:popView belowSubview:self.view];
            [UIView animateWithDuration:KWHC_NAV_ANIMATION_DURING delay:0 options:UIViewAnimationOptionCurveEaseOut animations:^{
                popView.center = CGPointMake(CGRectGetWidth(popView.frame) * 1.5, popView.center.y);
                sf.view.transform = [sf initAffineTransform:0];
                sf.view.alpha = 1.0;
            } completion:^(BOOL finished) {
                [popView removeFromSuperview];
                popView = nil;
                [_snapshootList removeLastObject];
            }];
        }
    }else{
        //清除popview的快照存储
        [_snapshootList removeLastObject];
        [_popView removeFromSuperview];
        _popView = nil;
        viewController = [super popViewControllerAnimated:animated];
    }
    _isTouchPop = NO;
    return viewController;
}

#pragma mark - UINavigationControllerDelegate
- (void)navigationController:(UINavigationController *)navigationController willShowViewController:(UIViewController *)viewController animated:(BOOL)animated{
    }
- (void)navigationController:(UINavigationController *)navigationController didShowViewController:(UIViewController *)viewController animated:(BOOL)animated{
    if(_topView != nil){
        _topView.userInteractionEnabled = YES;
    }
}

@end