ios - Using timer in a tableview re creates the timer after any scroll or table reload -

i'm using https://github.com/mineschan/mztimerlabel/ , in tableview cellforrowatindex using timer below:

uilabel *lbltimer=(uilabel *)[cell viewwithtag:10]; mztimerlabel *upgradetimer = [[mztimerlabel alloc] initwithlabel:lbltimer andtimertype:mztimerlabeltypetimer]; [upgradetimer setcountdowntime:timestamp]; [upgradetimer startwithendingblock:^(nstimeinterval timestamp) { lbltimer.text = @"✔"; }]; 

but after table reloading or scrolling, timer behaves strange , seems re-generates multiple timers counting in same place. how should fix while using timer?

appreciate help,

elias

i had @ mztimerlabel, , violates mvc badly. puts belongs model (the timer count's down time) view. problem comes from. views should able recreated without having side effects on model.

i recommend ditch class, , create own. it's quite easy achieve this.

1. create new class saves title , enddate
2. store instances of class in model backs table
3. create one nstimer refreshes tableview
4. set cells.

that's code need basic countdown in table. because not store data in view can scroll as like:

@interface timer : nsobject @property (strong, nonatomic) nsdate *enddate; @property (strong, nonatomic) nsstring *title; @end  @implementation timer @end  @interface masterviewcontroller () {     nsarray *_objects;     nstimer *_refreshtimer; } @end  @implementation masterviewcontroller  - (void)viewdidload {     [super viewdidload];      nsmutablearray *modelstore = [nsmutablearray arraywithcapacity:30];     (nsinteger = 0; < 30; i++) {         timer *timer = [[timer alloc] init];         timer.enddate = [nsdate datewithtimeintervalsincenow:i*30];         timer.title = [nsstring stringwithformat:@"timer %ld seconds", (long)i*30];         [modelstore addobject:timer];     }     _objects = modelstore; }  - (void)viewwillappear:(bool)animated {     [super viewwillappear:animated];     [_refreshtimer invalidate]; // timer should not exist, in case.     _refreshtimer = [nstimer timerwithtimeinterval:0.5f target:self selector:@selector(refreshview:) userinfo:nil repeats:yes];      // should fire while scrolling, need add timer manually:     [[nsrunloop currentrunloop] addtimer:_refreshtimer formode:nsrunloopcommonmodes]; }  - (void)viewdiddisappear:(bool)animated {     [super viewdiddisappear:animated];     [_refreshtimer invalidate];     _refreshtimer = nil; }  - (void)refreshview:(nstimer *)timer {     // refresh visible cells     (uitableviewcell *cell in [self.tableview visiblecells]) {         nsindexpath *indexpath = [self.tableview indexpathforcell:cell];         [self configurecell:cell forrowatindexpath:indexpath];     } }  #pragma mark - table view  - (nsinteger)tableview:(uitableview *)tableview numberofrowsinsection:(nsinteger)section {     return _objects.count; }  - (void)configurecell:(uitableviewcell *)cell forrowatindexpath:(nsindexpath *)indexpath {     timer *timer = _objects[indexpath.row];     cell.textlabel.text = timer.title;     nsinteger timeuntilend = (nsinteger)[timer.enddate timeintervalsincedate:[nsdate date]];     if (timeuntilend <= 0) {         cell.detailtextlabel.text = @"finished";     }     else {         nsinteger seconds = timeuntilend % 60;         nsinteger minutes = (timeuntilend / 60) % 60;         nsinteger hours = (timeuntilend / 3600);         cell.detailtextlabel.text = [nsstring stringwithformat:@"%02ld:%02ld:%02ld", (long)hours, (long)minutes, (long)seconds];     } }  - (uitableviewcell *)tableview:(uitableview *)tableview cellforrowatindexpath:(nsindexpath *)indexpath {     uitableviewcell *cell = [tableview dequeuereusablecellwithidentifier:@"cell" forindexpath:indexpath];     [self configurecell:cell forrowatindexpath:indexpath];     return cell; }  @end