Question

在iOS应用程序中将文字像字幕样式从下到上移动。我已经尝试了很长时间使用谷歌搜索，但我无法得到这个问题的完美答案，请提供此问题的任何代码。我是iOS应用程序的新手。

Answer 1

试试这个

#import "ViewController.h"

@interface ViewController ()

@end

@implementation ViewController

NSTimer *timer;
UILabel *label ;

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
    if (self) {
    }
    return self;
}

- (void)viewDidLoad
{
    [super viewDidLoad];
    timer =[NSTimer scheduledTimerWithTimeInterval:0.1 target:self selector:@selector(scrollText:) userInfo:nil repeats:YES];
    label = [[UILabel alloc] initWithFrame:CGRectMake(20, 50, 250, 20)];

    label.text =@"This is a string to be scroll";
    [self.view addSubview:label];

}

-(void)scrollText:(id)parameter{
    if (label.frame.origin.y <= 50) {
        [label setFrame:CGRectMake(label.frame.origin.x, 400, label.frame.size.width, label.frame.size.height)];
    }
    else
    [label setFrame:CGRectMake(label.frame.origin.x, label.frame.origin.y-5, label.frame.size.width, label.frame.size.height)];
}

@end

Answer 2

检查这个答案。

<强>·H

NSTimer *timer; 

float timeDuration;

<强>的.m

-(void)viewDidLoad  {

 [super viewDidLoad];
 timeDuration=1.0f; 
 timer = [NSTimer scheduledTimerWithTimeInterval:timeDuration   target:self selector:@selector(marqueeAnimation) userInfo:nil repeats:YES]; 
}

-(void)marqueeAnimation{

 UIImageView *imgView=[[UIImageView alloc]initWithFrame:CGRectMake(100, -100, 100, 100)];
 [imgView setImage:[UIImage imageNamed:@"root.PNG"]];
 [self.view addSubview:imgView];

 NSString *keyPath = @"transform.translation.y";

 CAKeyframeAnimation *translation = [CAKeyframeAnimation animationWithKeyPath:keyPath];

 translation.duration = timeDuration;
 translation.autoreverses = NO;
 NSMutableArray *values = [[NSMutableArray alloc] init];
 [values addObject:[NSNumber numberWithFloat:0.0f]];
 CGFloat height = [[UIScreen mainScreen] applicationFrame].size.height;
 [values addObject:[NSNumber numberWithFloat:height]];
 translation.values = values;

 NSMutableArray *timingFunctions = [[NSMutableArray alloc] init];
 [timingFunctions addObject:[CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionLinear]];
 translation.timingFunctions = timingFunctions;

 [imgView.layer addAnimation:translation forKey:keyPath]; 

 }

Answer 3

您可以在以下链接中找到相同的实现。这是COCOA CONTROL非常棒的地方。

COCOA CONTROLS

Answer 4

试试这个。这有效。在示例应用中尝试此操作，然后将其包含在您的应用中。

#import "ViewController.h"

@interface ViewController ()
@property(nonatomic, retain) NSTimer *timer;
@end

@implementation ViewController
- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
    [_txtView setText:@"hi..."];
    _timer = [NSTimer scheduledTimerWithTimeInterval:0.01f target:self selector:@selector(marqueeScroll) userInfo:nil repeats:YES];
}

-(void) marqueeScroll
{
    [_txtView setFrame:CGRectMake(_txtView.frame.origin.x, _txtView.frame.origin.y-1.0, _txtView.frame.size.width, _txtView.frame.size.height)];
    CGRect screen = [[UIScreen mainScreen] bounds];

    if(_txtView.frame.origin.y <= 0 )
    {
        [_txtView setFrame:CGRectMake(_txtView.frame.origin.x, screen.size.height,_txtView.frame.size.width, _txtView.frame.size.height)] ;
    }
}

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

@end

如果有任何错误，请告诉我。

使用textView在iOS应用程序中像字幕样式一样从下到上移动文本

4 个答案: