实现下拉弹出视图和Block的简单实现

实现效果如下:

实现代码如下:

 @interface ViewController ()<UIViewControllerTransitioningDelegate>

 {

     UILabel *optionLabel;   //显示选中值得label

     BOOL isPresentingOrDismissingOption;

     UIView *buildingOptionView;  //选择的视图

 }

 @end

 @implementation ViewController

 - (void)viewDidLoad {

     [super viewDidLoad];

     self.view.backgroundColor = [UIColor greenColor];

     buildingOptionView = [[UIView alloc] initWithFrame:CGRectMake(, , , )];

     [self.view addSubview:buildingOptionView];

     buildingOptionView.backgroundColor = [UIColor redColor];

     buildingOptionView.layer.cornerRadius = ;

     buildingOptionView.clipsToBounds = YES;

     UIGestureRecognizer *tapOnBuildingOpetionView = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(tapOnBuildingOpetionView:)];

     [buildingOptionView addGestureRecognizer:tapOnBuildingOpetionView];

     optionLabel = [[UILabel alloc] initWithFrame:CGRectMake(, , buildingOptionView.width - , )];

     optionLabel.text = @"第一教学楼";

     [buildingOptionView addSubview:optionLabel];

     optionLabel.textColor = [UIColor blackColor];

     UIImageView *arrowImageView = [[UIImageView alloc] initWithFrame:CGRectMake(optionLabel.right + ,optionLabel.top + ,,)];

     arrowImageView.image = [UIImage imageNamed:@"classroom_arrow_icon"];

     [buildingOptionView addSubview:arrowImageView];

 }

 //手势触发方法

 - (void)tapOnBuildingOpetionView:(UITapGestureRecognizer *)tap{

     NSLog(@"列表选择");

  //弹出选择列表

     OptionTableView *optionView = [[OptionTableView alloc]initWithFrame:CGRectMake(buildingOptionView.left + ,buildingOptionView.bottom + ,,) style:UITableViewStylePlain];

     optionView.buildingsArray = @[@"第一教学楼", @"第二教学楼", @"第三教学楼", @"第四教学楼", @"第五教学楼", @"第六教学楼", @"第七教学楼", @"第八教学楼"];

     [self.view addSubview:optionView];

     //block的实现,给label赋值

     [optionView setDismissOnBuilding:^(NSString *selectedBuilding) {

         optionLabel.text = selectedBuilding;

     }];

 }

OptionTableView的实现代码如下:

 #import <UIKit/UIKit.h>

 @interface OptionTableView : UITableView<UITableViewDataSource,UITableViewDelegate>

 @property (nonatomic, strong) NSArray *buildingsArray;
 @property (nonatomic, copy) void (^dismissOnBuilding)(NSString *building);

 @end

 static NSString *const buildingOptionCellId = @"Cell";

 @interface OptionTableView ()

 @end
 @implementation OptionTableView

 - (id)initWithFrame:(CGRect)frame style:(UITableViewStyle)style{

     self = [super initWithFrame:frame style:style];
     if (self) {

         self.dataSource = self;
         self.delegate = self;

         [self registerClass:[UITableViewCell class] forCellReuseIdentifier:buildingOptionCellId];
         self.backgroundColor = [UIColor blueColor];

     }
     return self;

 }

 #pragma mark - Table view dataSource

 //行数
 - (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section;
 {

     return self.buildingsArray.count;

 }

 //创建单元格
 - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath;

 {
     UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:buildingOptionCellId forIndexPath:indexPath];
     cell.textLabel.text = self.buildingsArray[indexPath.row];
     return cell;

 }

 #pragma mark - Table view delegate

 - (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {

     //block实现选中的值的传递

     if (self.dismissOnBuilding) {
         self.dismissOnBuilding(self.buildingsArray[indexPath.row]);
     }

     //当选择完毕表视图收起
     self.frame = CGRectZero;
 }

写的不好,有更好的方法,欢迎大家告诉我,谢谢!!!