I want to invoke a method 24 times but between each invocation I want an interval of 1 sec,
now am using
[NSTimer scheduledTimerWithTimeInterval:1 target:self selector:#selector(loadNumber) userInfo:nil repeats:YES];
but how to count invocations, I want to invalidate timer after 24 count can I invalidate that.
Create an instance variable for an int, it doesn't matter what you call it. Set it to "0" before you call the timer.
someInt = 0;
[NSTimer scheduledTimerWithTimeInterval:1 target:self selector:#selector(loadNumber:) userInfo:nil repeats:YES];
In the action that the time calls check the value of this number to make sure the action should be performed and increment the number.
- (void)loadNumber:(NSTimer *)sender
{
if (someInt <= 24) {
//do something
someInt ++;
}else{
[sender invalidate];
someInt = 0;
}
}
You should set up a counter in loadNumber, which will invalidate your NSTimer after your desired repeat counts.
Related
I am trying to use the current time in my movie player to increment a sliders value in my iPad app.
slider.maximumValue=10;
slider.minimumValue=0;
How can I increment slider.value from 0 to 10 in a specific time period?
You can use an NSTimer to repeatedly add 1 to your slider value if you know the specific time period beforehand:
NSTimer *aTimer = [NSTimer scheduledTimerWithTimeInterval:(timePeriod/slider.maximumValue)
target:self selector:#selector(timerFired:) userInfo:nil repeats:YES];
- (void)timerFired:(NSTimer*)theTimer {
[slider setValue:slider.value + 1.0];
if(slider.value == slider.maximumValue) {
[theTimer invalidate];
}
}
I have an application in which I want that when I run my application initially it should show a screen for 2 seconds that displays warning about the app and just after 2 seconds a countdown should start from 5 seconds that should decrement from 5 second to 1 second.
There are two ways:
[NSTimer timerWithTimeInterval: .....]
[self performSelector: withObject: afterDelay:]
so if i got your point you want to display a warning screen and after 2 seconds you want to show the user count down start from 5 and end at 1 .. well this can done easy by using a timer and counter as following :
define a NSTimer and start it once the warning view is shown .. your definition will be like this:
timer = [NSTimer scheduledTimerWithTimeInterval:1 target:self selector:#selector(timerFires) userInfo:nil repeats:YES];
[timer fire];
define a global integer and set its initial Value to 7 (lets suppose you name it counter).
-in timerFires selector you decreament counter by 1 and check its value when its equal to 5 start to show its vlaue on UILabel for example and when its 1 invalidate the timer and do you what you want at this point .. the timerFires will be like this:
- (void)timerFires
{
counter --;
if(counter ==5)
{
//show its Value
}
if(counter ==1)
{
[timer invalidate];
timer = nil;
//Do other stuff
}
}
[NSTimer scheduledTimerWithTimeInterval:60 target:self selector:#selector(updateFunction) userInfo:NULL repeats:YES];
In updateFunction you can write your code for count down.
You can also set "repeats:NO" and to call the updateFunction at the end of itself if it is necessary
I've got a program in which I want to code a timer which checks wether the user is idle or not. For that I wrote following code:
if (!idleTimer) {
NSLog(#"make");
idleTimer=[[NSTimer alloc]initWithFireDate:[NSDate dateWithTimeIntervalSinceNow:10.0]interval:10 target:self selector:#selector(idleTimerExceeded) userInfo:nil repeats:NO];
NSLog(#"madetimer with: %f, %#", idleTimer.timeInterval, idleTimer.fireDate);
}else {
NSLog(#"no reset timer: %f", idleTimer.timeInterval);
if (fabs([idleTimer.fireDate timeIntervalSinceNow]) < 9) {
NSLog(#"reset");
[idleTimer setFireDate:[NSDate dateWithTimeIntervalSinceNow:10]];
}
}
But somehow my logs show that the interval is always 0.0000 . Which means that something is wrong here. Can anybody help me?
ive never seen a timer look so complicated. try this:
write a method that checks if the user is idle (lets say idleChecker)
then make the timer repeatable and calls that method idleChecker
[NSTimer scheduledTimerWithTimeInterval:.5 target:self selector:#selector(idleChecker) userInfo:nil repeats:YES];
remember to declare the idleChecker method in the .h file
take note if u want to stop the timer event then you need to maintain a reference to it
NSTimer aTimer = [NSTimer scheduledTimerWithTimeInterval:.5 target:self selector:#selector(idleChecker) userInfo:nil repeats:YES];
then to stop it
[aTimer invalidate];
as for checking if its running i would just stick a nslog message in there stating something like "check for idle user"
This question already has answers here:
Closed 11 years ago.
Possible Duplicate:
Change the time interval of a Timer
So I have a timer:
timer=[NSTimer scheduledTimerWithTimeInterval:2 target:self selector:#selector(createNewImage) userInfo:nil repeats:YES];
And I would like that the timer decrease every ten seconds, that scheduledTimerWithTimeInterval goes to 1.5 after ten seconds then to 1.0 after 10 seconds... Is it possible to do this, and if it is possible, how can I do it?
You can't modify a timer after you created it. To change the timer interval, invalidate the old timer and create a new one with the new interval.
You don't have to use several timers, all you have to do is add a variable to use for the time interval, then create a method that invalidates the timer, changes the variable and starts the timer again. For instance you could make a method that starts the timer.
int iTimerInterval = 2;
-(void) mTimerStart {
timer = [NSTimer scheduledTimerWithTimeInterval:iTimerInterval target:self selector:#selector(createNewImage) userInfo:nil repeats:YES];
}
-(void) mTimerStop {
[timer invalidate];
iTimerInterval = iTimerInterval + 5;
[self mTimerStart];
}
This would be the simple way to decrease the timer interval and keep the timer going, but I would personally prefer using the one below, because it makes sure that the timer has only ran once, that way it will not duplicate the instance, forcing your app to become glitchy and it also makes things easier for you.
int iTimerInterval = 2;
int iTimerIncrementAmount = 5;
int iTimerCount;
int iTimerChange = 10; //Variable to change the timer after the amount of time
bool bTimerRunning = FALSE;
-(void) mTimerToggle:(BOOL)bTimerShouldRun {
if (bTimerShouldRun == TRUE) {
if (bTimerRunning == FALSE) {
timer = [NSTimer scheduledTimerWithTimeInterval:iTimerInterval target:self selector:#selector(mCreateNewImage) userInfo:nil repeats:YES];
bTimerRunning = TRUE;
}
} else if (bTimerShouldRun == FALSE) {
if (bTimerRunning == TRUE) {
[timer invalidate];
bTimerRunning = FALSE;
}
}
}
-(void) mCreateNewImage {
//Your Code Goes Here
if (iTimerCount % iTimerChange == 0) { //10 Second Increments
iTimerInterval = iTimerInterval + iTimerIncrementAmount; //Increments by Variable's amount
[self mTimerToggle:FALSE]; //Stops Timer
[self mTimerToggle:TRUE]; //Starts Timer
}
iTimerCount ++;
}
-(void) mYourMethodThatStartsTimer {
[self mTimerToggle:TRUE];
}
I didn't finish all of the coding, but this is most of what you will need. Just change a few things and you'll be good to go!
You will need a set or sequence of timers, one for each different time interval. Stop/invalidate one timer and start the next timer when you want to change to the next time interval in your time sequence.
I am new to iPhone,
What I want is that my timer call a function every second but for the very first time it must call the function at 2 second.
Any help will be really appreciated. Thanks
take a variable
BOOL isNotFirstTime;
And in the function that gets triggered after each 4 secs add the following code at the starting
-(void)AfterOneSecondsFuction
{
if(!isNotFirstTime)
{
isNotFirstTime=YES;
return;
}
//YOUR CODE HERE...
}
This is how you give a call to the function
NSTimer scheduledTimerWithTimeInterval:1.0 target:self selector:#selector(AfterOneSecondsFuction) userInfo:nil repeats:YES];
First schedule a timer and have a BOOL variable say isFirstTime set as YES;
[NSTimer scheduledTimerWithTimeInterval:1.0 target:self selector:#selector(doSomething) userInfo:nil repeats:YES];
and in
- (void)doSomething
{
if(isFirstTime)
{
isFirstTime = NO;
return;
}
// Do something
}