navigation中左滑pop的三种方法

<h2 id="系统自带pop方法">系统自带pop方法如果我们没有对navigation中的back按钮进行自定义，我们可以直接使用系统自带的左滑pop方法。但是如果我们对back按钮，进行了自定义，我们就要对

self.navigationController.interactivePopGestureRecognizer

这个属性进行设置了。关键代码__weak typeof(self) weakSelf = self;self.navigationController.interactivePopGestureRecognizer.delegate =weakSelf;

下面是实例代码：

（继承AbeViewController类，就可以使用系统自带的pop方法。）

#import "AbeViewController.h"

@interface AbeViewController ()

@end

@implementation AbeViewController

- (void)viewDidLoad {
[super viewDidLoad];
}

- (void)viewDidAppear:(BOOL)animated{
//**************方法一****************//
//设置滑动回退
__weak typeof(self) weakSelf = self;                self.navigationController.interactivePopGestureRecognizer.delegate = weakSelf;
//判断是否为第一个view
if (self.navigationController && [self.navigationController.viewControllers count] == 1) {
self.navigationController.interactivePopGestureRecognizer.enabled = NO;
}
}

#pragma mark- UIGestureRecognizerDelegate
//**************方法一****************//
- (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer{
return YES;
}

@end

自定义边缘左滑手势方法

就是实现了一个手势方法，触发这个手势方法时pop。

下面是实例代码：

（继承AbeViewController类，就可以使用自定义边缘左滑手势的pop方法。）

#import "AbeViewController.h"

@interface AbeViewController ()

@end

@implementation AbeViewController

- (void)viewDidLoad {
[super viewDidLoad];
}

- (void)viewDidAppear:(BOOL)animated{
//*************方法二*****************//
UIScreenEdgePanGestureRecognizer *edgePanGestureRecognizer = [[UIScreenEdgePanGestureRecognizer alloc] initWithTarget:self action:@selector(edgePanGesture:)];
edgePanGestureRecognizer.delegate = self;
edgePanGestureRecognizer.edges = UIRectEdgeLeft;
[self.view addGestureRecognizer:edgePanGestureRecognizer];
}

- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
}

#pragma mark- private method
//*************方法二*****************//
- (void)edgePanGesture:(UIScreenEdgePanGestureRecognizer*)edgePanGestureRecognizer{
[self.navigationController popViewControllerAnimated:YES];
}

#pragma mark- UIGestureRecognizerDelegate
//**************方法二****************//
- (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer{
if (self.navigationController && [self.navigationController.viewControllers count] == 1) {
return NO;
}
return YES;
}

@end

自定义view任何位置左移pop

在view中，任何位置左移触发pop方法。其实就是建立了一个UIPanGestureRecognizer手势，然后该手势触发方法。知识点：[panGestureRecognizer locationInView:XX] 获取pan手势的CGPoint。panGestureRecognizer.state pan的状态self.interactivePopGestureRecognizer.enabled = NO; 原生左滑无效

下面是实例代码：

（继承ABENavViewController类，就可以使用自定义view左滑手势的pop方法； ABENavViewController为UINavigationController的子类）

#import "ABENavViewController.h"

@interface ABENavViewController ()

@property (strong, nonatomic)UIPanGestureRecognizer *panGestureRecognizer;
@property (strong, nonatomic)UIImageView *backView;

@property (strong, nonatomic)NSMutableArray *backImgs;
@property (assign) CGPoint panBeginPoint;
@property (assign) CGPoint panEndPoint;

@end

@implementation ABENavViewController
- (instancetype)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil{
self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
if (self) {
//initlization
}
return self;
}

- (void)loadView{
[super loadView];

[self initilization];
}

- (void)viewDidLoad {
[super viewDidLoad];
[self loadBaseUI];
}

- (void)initilization{
self.backImgs = [[NSMutableArray alloc] init];
}

- (void)loadBaseUI{
//原生方法无效
self.interactivePopGestureRecognizer.enabled = NO;

//设置手势
self.panGestureRecognizer = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(panGestureRecognizerAction:)];
[self.view addGestureRecognizer:self.panGestureRecognizer];
}

#pragma mark- public method
- (void)pushViewController:(UIViewController *)viewController animated:(BOOL)animated{
//截图
UIGraphicsBeginImageContextWithOptions([UIScreen mainScreen].bounds.size, YES, 1.0);
[[UIApplication sharedApplication].keyWindow.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *img = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
[self.backImgs addObject:img];

[super pushViewController:viewController animated:animated];
}

- (UIViewController *)popViewControllerAnimated:(BOOL)animated{
[_backImgs removeLastObject];

return [super popViewControllerAnimated:animated];
}

#pragma mark- private method
- (void)panGestureRecognizerAction:(UIPanGestureRecognizer*)panGestureRecognizer{
if ([self.viewControllers count] == 1) {
return ;
}

if (panGestureRecognizer.state == UIGestureRecognizerStateBegan) {
NSLog(@"滑动开始");
//存放滑动开始的位置
self.panBeginPoint = [panGestureRecognizer locationInView:[UIApplication sharedApplication].keyWindow];
//插入图片
[self insertLastViewFromSuperView:self.view.superview];

}else if(panGestureRecognizer.state == UIGestureRecognizerStateEnded){
NSLog(@"滑动结束");
//存放数据
self.panEndPoint = [panGestureRecognizer locationInView:[UIApplication sharedApplication].keyWindow];

if ((_panEndPoint.x - _panBeginPoint.x) > 50) {
[UIView animateWithDuration:0.3 animations:^{
[self moveNavigationViewWithLenght:[UIScreen mainScreen].bounds.size.width];
} completion:^(BOOL finished) {
[self removeLastViewFromSuperView];
[self moveNavigationViewWithLenght:0];

4000
[self popViewControllerAnimated:NO];
}];

}else{
[UIView animateWithDuration:0.3 animations:^{
[self moveNavigationViewWithLenght:0];
}];
}
}else{
//添加移动效果
CGFloat panLength = ([panGestureRecognizer locationInView:[UIApplication sharedApplication].keyWindow].x - _panBeginPoint.x);
if (panLength > 0) {
[self moveNavigationViewWithLenght:panLength];
}
}

}

/**
*  移动视图界面
*
*  @param lenght 移动的长度
*/
- (void)moveNavigationViewWithLenght:(CGFloat)lenght{

//图片位置设置
self.view.frame = CGRectMake(lenght, self.view.frame.origin.y, self.view.frame.size.width, self.view.frame.size.height);
//图片动态阴影
_backView.alpha = (lenght/[UIScreen mainScreen].bounds.size.width)*2/3 + 0.33;
}

/**
*  插图上一级图片
*
*  @param superView 图片的superView
*/
- (void)insertLastViewFromSuperView:(UIView *)superView{
//插入上一级视图背景
if (_backView == nil) {
_backView = [[UIImageView alloc] initWithFrame:[UIScreen mainScreen].bounds];
_backView.image = [_backImgs lastObject];;
}
[self.view.superview insertSubview:_backView belowSubview:self.view];
}

/**
*  移除上一级图片
*/
- (void)removeLastViewFromSuperView{
[_backView removeFromSuperview];
_backView = nil;
}

@end