Question

I have a view containing a segmented controller and a UIDatePicker that only shows 24-h time. I want to be able to set different times depending on what the segmented control says. So “Mon” would correspond to one time, “Tue” to another and so on. I have this working. However, I also would like to animate the picker when the user changes button on the segmented controller. As of now I have in my action method linked to the segmented controller this:

[timePicker setDate:date animate:YES];

Where date is a NSDate formatted like so: HH:mm

As I said, it will change to the date but it will not animate the operation. Anyone knows why it doesn’t animate?

BTW, although I have set the formatter to be “HH:mm” if I use NSLog to print it I still get the whole 1970-01-01 +02:00:00 string printed. I assume that the only HH:mm is sent to the datepicker anyway and that it is just NSLog that prints the whole thing?

EDIT: Here is the code for the actual view controller, and this is running SDK4

#import "FlipsideViewController.h"

@implementation FlipsideViewController

@synthesize delegate, times, weatherImage, condition, timePicker;


- (void)viewDidLoad {

    [super viewDidLoad];
    self.view.backgroundColor = [UIColor viewFlipsideBackgroundColor];

    UIImage *image = [UIImage imageNamed:@"sunny.png"];
    weatherImage.image = image;

    WeatherClockAppDelegate *appDelegate = (WeatherClockAppDelegate *)[[UIApplication sharedApplication] delegate];

    times = appDelegate.times;

    [timePicker addTarget:self action:@selector(timePickerAction:) forControlEvents:UIControlEventValueChanged];

    NSDateFormatter *df = [[NSDateFormatter alloc] init];
    [df setDateFormat:@"HH:mm"];
    NSDate *sunnyDate = [df dateFromString: [times objectAtIndex:0]];
    [df release];

    [timePicker setDate:sunnyDate animated:NO];


}

- (IBAction)done:(id)sender {

    if (!busy) {

        [self.parentViewController dismissModalViewControllerAnimated:YES];

        for (NSString *s in times) {
            NSLog(@"Set times: %@", s);
        }
    }

}

- (IBAction)segmentedAction {

    NSDateFormatter *df = [[NSDateFormatter alloc] init];
    [df setDateFormat:@"HH:mm"];

    switch (self.condition.selectedSegmentIndex) {

        case 0:

            self.weatherImage.image = [UIImage imageNamed:@"sunny.png"];

            NSDate *sunnyDate = [df dateFromString: [times objectAtIndex:0]];

            [timePicker setDate:sunnyDate animated:YES];

            break;

        case 1:

            self.weatherImage.image = [UIImage imageNamed:@"cloudy.png"];

            NSDate *cloudyDate = [df dateFromString: [times objectAtIndex:1]];

            NSLog(@"Cloudydate: %@", cloudyDate);

            [timePicker setDate:cloudyDate animated:YES];

            break;

        case 2:

            self.weatherImage.image = [UIImage imageNamed:@"rain.png"];

            NSDate *rainyDate = [df dateFromString: [times objectAtIndex:2]];

            [timePicker setDate:rainyDate animated:YES];

            break;

        case 3:

            self.weatherImage.image = [UIImage imageNamed:@"final.png"];

            NSDate *finalDate = [df dateFromString: [times objectAtIndex:3]];

            [timePicker setDate:finalDate animated:YES];

            break;

    }

    [df release];
}


- (IBAction)timePickerAction:(id)sender {

    NSDateFormatter *df = [[NSDateFormatter alloc] init];
    [df setDateFormat:@"HH:mm"];
    NSString *date = [NSString stringWithFormat:@"%@", [df stringFromDate:timePicker.date]];
    NSLog(@"%@", date);
    [df release];

    switch (self.condition.selectedSegmentIndex) {

        case 0:

            [times replaceObjectAtIndex:0 withObject:date];

            break;

        case 1:

            [times replaceObjectAtIndex:1 withObject:date];

            break;

        case 2:

            [times replaceObjectAtIndex:2 withObject:date];         

            break;

        case 3:

            [times replaceObjectAtIndex:3 withObject:date];

            break;

    }

}


- (void)didReceiveMemoryWarning {
    // Releases the view if it doesn't have a superview.
    [super didReceiveMemoryWarning];

    // Release any cached data, images, etc that aren't in use.
}


- (void)viewDidUnload {
    // Release any retained subviews of the main view.
    // e.g. self.myOutlet = nil;
}


/*
 // Override to allow orientations other than the default portrait orientation.
 - (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation {
 // Return YES for supported orientations
 return (interfaceOrientation == UIInterfaceOrientationPortrait);
 }
 */


- (void)dealloc {

    [times release];
    [weatherImage release];
    [condition release];
    [timePicker release];
    [super dealloc];
}


@end

Answer 1

It’s not animating for me too on iOS4.0.1 SDK, both on simulator and device. No idea if it was working before 4.0.1.

To try it out, add the following code into the sample project UICatalog, PickerViewController.m in – (void)viewDidLoad

UIButton *button = [UIButton buttonWithType:UIButtonTypeRoundedRect];
button.frame = labelFrame;
[button setTitle:@"Spin me" forState:UIControlStateNormal];
[button addTarget:self action:@selector(spin) forControlEvents:UIControlEventTouchUpInside];
[self.view addSubview:button];

Add also a method above – (void)viewDidLoad in PickerViewController.m

- (void) spin {
    [datePickerView setDate:[NSDate date] animated:YES];
}

Based on the code, if you run the project, navigate to Pickers, select UIDatePicker, spin the date wheel to any date other than today, hit the ‘Spin Me’ button, it should set the wheel back to today, BUT it wouldn’t animate.

I’m having a hard time figuring out if this is just a bug, and if there’s any workaround. Pretty surprise to hear that setDate:animated: is working for some of you.