iOS抽屉效果开发案例分享

#import "ViewController.h"
 
@interface ViewController ()
@property(nonatomic, weak) UIView *mainV;
@property(nonatomic, weak) UIView *leftV;
@property(nonatomic, weak) UIView *rightV;
@end

#pragma mark - 添加子控件
- (void)setUpChildViews {  
 UIView *leftV = [[UIView alloc]initWithFrame:self.view.bounds];  
 leftV.backgroundColor = [UIColor orangeColor];  
 [self.view addSubview:leftV];  
 _leftV = leftV;  
 UIView *rightV = [[UIView alloc]initWithFrame:self.view.bounds];  
 rightV.backgroundColor = [UIColor groupTableViewBackgroundColor];  
 [self.view addSubview:rightV];  
 _rightV = rightV;  
 UIView *mainV = [[UIView alloc]initWithFrame:self.view.bounds];  
 mainV.backgroundColor = [UIColor yellowColor];  
 [self.view addSubview:mainV];  
 _mainV = mainV;
}
 
- (void)viewDidLoad {
 [super viewDidLoad];
  
 //添加子控件
 [self setUpChildViews];
  
 //添加Pan手势
 UIPanGestureRecognizer *pan = [[UIPanGestureRecognizer alloc]initWithTarget:self action:@selector(pan:)];
  
 [self.view addGestureRecognizer:pan];
  
 //添加点按手势，在主视图上任意位置点击回到屏幕开始位置
 UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc]initWithTarget:self action:@selector(tap)];
  
 [self.view addGestureRecognizer:tap];
  
}

#pragma mark - 手势识别方法
#define targetL -230
#define targetR 200
#define screenW [UIScreen mainScreen].bounds.size.width
- (void)pan:(UIPanGestureRecognizer *)pan {
  
 //获取手势移动的位置
 CGPoint tranP = [pan translationInView:self.view];
  
 //获取x的偏移量
 CGFloat offsetX = tranP.x;
  
 //修改mainV的frame
 _mainV.frame = [self frameWithOffsetX:offsetX];
  
 //判断mainV的x是否大于0
 [self observeValueForKeyPath:nil ofObject:nil change:nil context:nil];
  
 //复位
 [pan setTranslation:CGPointZero inView:self.view];
  
 //判断当手势结束的时候，定位
 if (pan.state == UIGestureRecognizerStateEnded) {
   
  CGFloat target = 0;
   
  if (_mainV.frame.origin.x > screenW * 0.5) {
   //定位到右边
   target = targetR;
  }else if(CGRectGetMaxX(_mainV.frame) < screenW * 0.5) {
   //定位到左边
   target = targetL;
  }
   
  //获取X轴需要移动的偏移量
  CGFloat offsetX = target - _mainV.frame.origin.x;
   
  [UIView animateWithDuration:0.25 animations:^{
    
   _mainV.frame = target == 0 ? self.view.bounds : [self frameWithOffsetX:offsetX];
 
  }];
   
 }
  
}

- (void)tap {
  
 [UIView animateWithDuration:0.25 animations:^{
  _mainV.frame = self.view.bounds;
 }];
  
}

#define kMaxY 80
#pragma mark - 根据offsetX计算mainV的frame
- (CGRect)frameWithOffsetX:(CGFloat)offsetX {
  
 //获取上一次的frame
 CGRect frame = _mainV.frame;
  
 //获取屏幕的高度
 CGFloat screenH = [UIScreen mainScreen].bounds.size.height;
  
 //获取屏幕的宽度
 //CGFloat screenW = [UIScreen mainScreen].bounds.size.width;
  
 //X轴平移一点对应Y轴需要平移的距离
 CGFloat offsetY = offsetX * kMaxY / screenW;
  
 //获取上一次的高度
 CGFloat preH = frame.size.height;
  
 //获取上一次的宽度
 CGFloat preW = frame.size.width;
  
 //获取当前高度
 CGFloat curH = preH - 2 * offsetY;
 //如果是向左滑动
 if(frame.origin.x < 0) {
  curH = preH + 2 * offsetY;
 }
  
 //获取尺寸的缩放比例
 CGFloat scale = curH / preH;
  
 //获取当前宽度
 CGFloat curW = preW * scale;
  
 //获取当前x
 frame.origin.x += offsetX;
  
 //获取当前y
 CGFloat y = (screenH - curH) / 2;
 frame.origin.y = y;
  
 frame.size.width = curW;
 frame.size.height = curH;
  
 return frame;
  
}

- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary<NSString *,id> *)change context:(void *)context {
  
 if(_mainV.frame.origin.x > 0) {//往右边滑动
  _rightV.hidden = YES;
 }else if(_mainV.frame.origin.x < 0) {//往左边滑动
  _rightV.hidden = NO;
 }
  
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
 
 return 30;
}
 
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
  
  
 static NSString *ID = @"cell";
  
 UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:ID];
  
 if(cell == nil) {
  cell = [[UITableViewCell alloc]initWithStyle:UITableViewCellStyleDefault reuseIdentifier:ID];
 }
  
 cell.textLabel.text = [NSString stringWithFormat:@"第%ld行", indexPath.row];
  
 return cell;
}

- (void)viewDidLoad {
 [super viewDidLoad];
  
 XXViewController *vc = [[XXViewController alloc]init];
 vc.view.frame = self.view.bounds;
  
 //让vc成为主视图控制器的子控制器
 [self addChildViewController:vc];
  
 //主视图展示tableView
 [self.mainV addSubview:vc.view];
  
}

#import <UIKit/UIKit.h>
 
@interface ViewController : UIViewController
@property(nonatomic, weak, readonly) UIView *mainV;
@property(nonatomic, weak, readonly) UIView *leftV;
@property(nonatomic, weak, readonly) UIView *rightV;
@end