1.代理类的实现文件
#import "AppDelegate.h"
#import"MainViewController.h"
@interface AppDelegate ()
@end
@implementation AppDelegate
//程序一旦启动会调用的方法
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
//获取当前设备的屏幕的宽和高
CGRect rect = [[UIScreen mainScreen] bounds];
//主窗口的创建过程 主窗口有且仅有一个 UIView:视图类
self.window=[[UIWindow alloc] initWithFrame:CGRectMake(0, 0, rect.size.width, rect.size.height)];
//self.window.backgroundColor=[UIColor blackColor];
self.window.backgroundColor=[UIColor colorWithRed:255/255.0 green:0.0 blue:0.0 alpha:1.0];
UILabel* label=[[UILabel alloc] initWithFrame:CGRectMake(100, 100, 100, 44)];//实例化
label.text=@"用户名";//设置标签的文本
label.textAlignment=NSTextAlignmentCenter;//设置文本的显示方式（居中，左对齐，右对齐）
label.font=[UIFont systemFontOfSize:18];//设置标签文本的字体大小
label.textColor=[UIColor greenColor];//设置文本的颜色
[self.window addSubview:label];//添加子视图
//UIViewController视图控制器类
//UIViewController* ctr=[[UIViewController alloc] init];
//[UIColor clearColor]; //透明色
MainViewController* ma=[[MainViewController alloc] init];
[self.window setRootViewController:ma];//视图控制器类：分层管理视图
[self.window makeKeyAndVisible];//让主窗口可见
return YES;
}
//程序即将取消活跃状态会回调的方法
- (void)applicationWillResignActive:(UIApplication *)application {
}
//程序确实进入后台会回调的方法
- (void)applicationDidEnterBackground:(UIApplication *)application {
}
//程序即将进入前台会回调的方法
- (void)applicationWillEnterForeground:(UIApplication *)application {
}
//程序为活跃状态会回调的方法
- (void)applicationDidBecomeActive:(UIApplication *)application {
}
//如果设备不支持后台运行，点击home键 程序退出， 此方法会被回调
//程序不支持后台运行设置：FirstApp-Info.plist文件->增加键值对Application does not run in background=YES 即可。
- (void)applicationWillTerminate:(UIApplication *)application {
}
@end
2.控制器类的实现文件
#import "MainViewController.h"
#import"UIColor+Random.h"
@interface MainViewController ()
@end
@implementation MainViewController
- (void)viewDidLoad {
[super viewDidLoad];
//设置当前类的属性View背景色
self.view.backgroundColor=[UIColor blackColor];
//获取plist文件中的内容
NSString* path=[[NSBundle mainBundle] pathForResource:@"弹幕" ofType:@"plist"];
self.array=[NSArray arrayWithContentsOfFile:path];
//用指定路径文件内容初始化数组
//计时器
[NSTimer scheduledTimerWithTimeInterval:0.3 target:self selector:@selector(initDate) userInfo:nil repeats:YES];
//参数一：时间间隔 参数二：目标 参数三:指定方法 参数四：是否重复执行指定的方法
// Do any additional setup after loading the view.
}
- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
//创建标签并添加到视图中
-(void)initDate
{
UILabel* label=[[UILabel alloc] init];
[label setFrame:CGRectMake(300, arc4random_uniform(568), 360, 44)];
label.textAlignment=NSTextAlignmentLeft;
label.text = [self.array objectAtIndex:arc4random_uniform(11)];
//从数组总随机获取字符串作为标签的文本
label.textColor = [UIColor randomColor];
label.font = [UIFont systemFontOfSize:14];
[self.view addSubview:label];
[self move:label];
}
//移动标签
-(void)move:(UILabel*)_label
{
[UIView animateWithDuration:5.0 animations:^(){
[_label setFrame:CGRectMake(-180, _label.frame.origin.y, _label.frame.size.width, _label.frame.size.height)];
} completion:^(BOOL finished) {
[_label removeFromSuperview];
}];//参数一：动画的持续时间， 参数二：指定动画 参数三：动画结束后所作的操作。
}
/*
#pragma mark - Navigation
// In a storyboard-based application, you will often want to do a little preparation before navigation
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
}
*/
@end
3.效果：