我需要创建多个具有 MARQUEE 效果的 UIView,如 HTML <marquee>
标签。
我首先需要动态创建 UIView。
为动态创建的UIView添加MARQUEE效果后。
我们将不胜感激。
最佳答案
您的意思是一个 View 可以通过从右向左缓慢滚动来显示比 View 宽度更宽的字符串集合?你需要构建它。我做过一次,像这样子类化 UIScrollView:
// CrawlView.h
#import <UIKit/UIKit.h>
@interface CrawlView : UIScrollView
@property (assign, nonatomic) NSTimeInterval period;
@property (strong, nonatomic) NSMutableArray *messages;
- (void)go;
@end
// CrawlView.m
#import "CrawlView.h"
// distance between neighboring strings. could make this a public property
#define kPADDING 16.0
@interface CrawlView ()
@property (assign, nonatomic) CGFloat messagesWidth;
@end
@implementation CrawlView
@synthesize period=_period;
@synthesize messages=_messages;
@synthesize messagesWidth=_messagesWidth;
- (void)buildSubviews {
for (UIView *subview in [self subviews]) {
if ([subview isKindOfClass:[UILabel self]]) {
[subview removeFromSuperview];
}
}
CGFloat xPos = kPADDING;
for (NSString *message in self.messages) {
UILabel *label = [[UILabel alloc] initWithFrame:CGRectZero];
label.text = message;
CGSize size = [message sizeWithFont:label.font];
CGFloat width = size.width + kPADDING;
label.frame = CGRectMake(xPos, 0.0, width, self.frame.size.height);
[self addSubview:label];
xPos += width;
}
self.messagesWidth = xPos;
self.contentSize = CGSizeMake(xPos, self.frame.size.height);
self.contentOffset = CGPointMake(-self.frame.size.width, 0.0);
}
- (void)setMessages:(NSMutableArray *)messages {
if (_messages != messages) {
_messages = messages;
[self buildSubviews];
}
}
- (void)go {
if (!self.period) self.period = self.messagesWidth / 100;
// so it always takes about the same (fudged, but reasonable) amount of time to scroll the whole array
[UIView animateWithDuration:self.period
delay:0.0
options:UIViewAnimationOptionCurveLinear |UIViewAnimationOptionRepeat
animations:^{
self.contentOffset = CGPointMake(self.messagesWidth, 0.0);
} completion:^(BOOL finished){}];
}
@end
关于iphone - 如何在 iphone 中创建具有 Marquee Effect 的动态多个 uiview,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/9919455/