Question

我必须管理每个UITableViewCell的倒数计时器。当那个时间结束时，必须删除cell。我已经开始实施，但坚持如何删除那个时间完成的特定cell。我的应用程序有多行，但出于演示目的，我只显示了三行。

我的方法是：在TableViewController.m

#import "TableViewController.h"
#import "CountdownTimer.h"

@interface TableViewController () <CountdownTimerDelegate>
@property (nonatomic, strong) NSArray *demoList;
@end

@implementation TableViewController

- (void)viewDidLoad
{
    [super viewDidLoad];

    self.demoList = [self dataSource];
}

- (NSArray *)dataSource {
    NSDictionary *demoOne = @{@"DemoId": [NSNumber numberWithInt:1],
                                 @"DemoName": @"Timer One",
                                 @"DueDate": [[NSDate date] dateByAddingTimeInterval:60]};

    NSDictionary *demoTwo = @{@"DemoId": [NSNumber numberWithInt:2],
                                 @"DemoName": @"Timer Two",
                                 @"DueDate": [[NSDate date] dateByAddingTimeInterval:120]};

    NSDictionary *demoThree = @{@"DemoId": [NSNumber numberWithInt:3],
                                   @"DemoName": @"Timer Theree",
                                   @"DueDate": [[NSDate date] dateByAddingTimeInterval:180]};

    return @[demoOne, demoTwo, demoThree];
}

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

#pragma mark - Table view data source

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
    // Return the number of sections.
    return 1;
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
    // Return the number of rows in the section.
    return self.demoList.count;
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    static NSString *CellIdentifier = @"Cell";
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath];

    // Configure the cell...
    if (cell == nil) {
        cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:CellIdentifier];
    }

    cell.textLabel.text = [[self.demoList objectAtIndex:indexPath.row] objectForKey:@"DemoName"];

    NSDate *dueDate = [[self.demoList objectAtIndex:indexPath.row] objectForKey:@"DueDate"];
    NSNumber *demoId = [[self.demoList objectAtIndex:indexPath.row] objectForKey:@"DemoId"];

    CountdownTimer *timer = [[CountdownTimer alloc] init];
    timer.delegate = self;
    [timer startCountdownTimerFordemo:demoId endDate:dueDate withUpdatingLable:cell.detailTextLabel];

    return cell;
}

#pragma mark - CountdownTimerDelegate

- (void)countdownTimer:(CountdownTimer *)ct didFinishTimerFordemo:(NSNumber *)demoId
{
    // Here I have to delete row having this demoId.
}

In CountdownTimer.h
@protocol CountdownTimerDelegate;

@interface CountdownTimer : NSObject

@property (assign) id <CountdownTimerDelegate> delegate;
- (void)startCountdownTimerFordemo:(NSNumber *)dId endDate:(NSDate *)date withUpdatingLable:(UILabel *)label;
@end

@protocol CountdownTimerDelegate <NSObject>
- (void)countdownTimer:(CountdownTimer *)ct didFinishTimerFordemo:(NSNumber *)demoId;
@end

In CountdownTimer.m
@interface CountdownTimer () {
    NSDate *dueDate;
    NSNumber *demoId;
}

// The repeating timer is a assign/weak property.
@property (assign) NSTimer *countdownTimer;
@property (retain, nonatomic) UILabel *updatingLabel;

@end

@implementation CountdownTimer

- (void)startCountdownTimerFordemo:(NSNumber *)dId endDate:(NSDate *)date withUpdatingLable:(UILabel *)label
{
    self.updatingLabel = label;
    demoId = dId;
    dueDate = date;

    // Cancel a preexisting timer.
    [self.countdownTimer invalidate];

    NSTimer *timer = [NSTimer scheduledTimerWithTimeInterval:1
                                                      target:self selector:@selector(updateRemainingTime:)
                                                    userInfo:nil repeats:YES];

    self.countdownTimer = timer;
}

- (void)updateRemainingTime:(NSTimer*)theTimer
{
    int interval = (int)[dueDate timeIntervalSinceDate:[NSDate date]];

    int minutes = floor(interval/60);
    int seconds = round(interval - minutes * 60);

    if ((minutes > 0 || seconds >= 0) && minutes >= 0) {
        if (minutes >= 0)
            [self.updatingLabel setText:[NSString stringWithFormat:@"%d:%02d", minutes, seconds]];

        if (seconds == 0) {
            seconds = 59;
            minutes = minutes - 1;
        } else {
            seconds = seconds - 1;
        }
    } else {
        [self.countdownTimer invalidate];
        [self.delegate countdownTimer:self didFinishTimerFordemo:demoId];
    }
}

Answer 1

你可以比较数组中存在的每个对象你必须使用可变数组听到的是代码

    @property (nonatomic, retain) NSMutableArray *demoList; //change to NSMutableArray

    - (NSMutableArray *)dataSource {
   NSDictionary *demoOne = @{@"DemoId": [NSNumber numberWithInt:1],
   @"DemoName": @"Timer One",
   @"DueDate": [[NSDate date] dateByAddingTimeInterval:60]};

   NSDictionary *demoTwo = @{@"DemoId": [NSNumber numberWithInt:2],
   @"DemoName": @"Timer Two",
   @"DueDate": [[NSDate date] dateByAddingTimeInterval:120]};

   NSDictionary *demoThree = @{@"DemoId": [NSNumber numberWithInt:3],
   @"DemoName": @"Timer Theree",
   @"DueDate": [[NSDate date] dateByAddingTimeInterval:180]};

   return [[[NSMutableArray alloc]initWithObjects:demoOne,demoTwo,demoThree,nil]autorelease]; //return a NSMutableArray
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{

  // return [mutArray count];
    int k = self.demoList.count;
    if(k > 0)
      return k;
    else
      return 0;
 }

- (void)countdownTimer:(CountdownTimer *)ct didFinishTimerFordemo:(NSNumber *)demoId
{
  // Here I have to delete row having this demoId.
  int count = [self.demoList count];
  int indxTodelete;
  NSString *key = @"DemoId";
  for(int i = 0; i < count ; i++)
  {

     NSDictionary *aDict = [self.demoList objectAtIndex:i];
     NSNumber *aNum = [aDict objectForKey:key];
     if([aNum isEqualToNumber:demoId])
     {
         indxTodelete = i;
     }

 }
  [self.aTableView beginUpdates];
  [self.demoList removeObjectAtIndex:indxTodelete];
   NSIndexPath *indexPath = [NSIndexPath indexPathForRow:indxTodelete inSection:0];
   [self.aTableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationFade];
   [self.aTableView endUpdates];

 }

希望这会有所帮助：）

管理每个UITableViewCell的倒数计时器

1 个答案: