移动物体
CABasicAnimation *theAnimation; theAnimation=[CABasicAnimation animationWithKeyPath:@"transform.translation.x"]; theAnimation.duration=1; theAnimation.repeatCount=2; theAnimation.autoreverses=YES; theAnimation.fromValue=[NSNumber numberWithFloat:0]; theAnimation.toValue=[NSNumber numberWithFloat:-60]; [view.layer addAnimation:theAnimation forKey:@"animateLayer"];
参考：
| Field Key Path |
Description |
| rotation.x |
The rotation, in radians, in the x axis. |
| rotation.y |
The rotation, in radians, in the y axis. |
| rotation.z |
The rotation, in radians, in the z axis. |
| rotation |
The rotation, in radians, in the z axis. This is identical to setting the rotation.z field. |
| scale.x |
Scale factor for the x axis. |
| scale.y |
Scale factor for the y axis. |
| scale.z |
Scale factor for the z axis. |
| scale |
Average of all three scale factors. |
| translation.x |
Translate in the x axis. |
| translation.y |
Translate in the y axis. |
| translation.z |
Translate in the z axis. |
| translation |
Translate in the x and y axis. Value is an NSSize or CGSize. |
访问别的类的属性或者方法
myAppDelegate *appDelegate
= (myAppDelegate *)[[UIApplication sharedApplication] delegate];
[[[appDelegate rootViewController] flipsideViewController] myMethod];
遍历子视图
for (UIImageView *anImage in [self.view subviews]) {
if (anImage.tag == 1) {
// do something
}
}
播放音乐
// 设置音乐文件路径
path = [[NSBundle mainBundle] pathForResource:@"mani" ofType:@"mp3"];
// 判断是否可以访问这个文件
if ([[NSFileManager defaultManager] fileExistsAtPath:path])
{
// 设置 player
player = [[AVAudioPlayer alloc] initWithContentsOfURL:
[NSURL fileURLWithPath:path] error:nil];
// 调节音量 (范围从0到1)
player.volume = 0.4f;
// 准备buffer，减少播放延时的时间
[player prepareToPlay];
// 设置播放次数，0为播放一次，负数为循环播放
[player setNumberOfLoops:-1];
[player play];
}
随机数
rand()
例：
[_cloud02 setFrame:CGRectMake(-1024+rand()%600, -768+rand()%300, 2048, 1536)]; [_cloud01 setFrame:CGRectMake(-1024+rand()%600, -768+rand()%300, 2048, 1536)];
Timer
每秒调用
[NSTimer scheduledTimerWithTimeInterval:1
target:self
selector:@selector(myMethod)
userInfo:nil
repeats:YES];
如果需要传递参数的话：
[NSTimer scheduledTimerWithTimeInterval:1 target:self
selector:@selector(myMethod)
userInfo:myObject
repeats:YES];
-(void)myMethod:(NSTimer*)timer {
// Now I can access all the properties and methods of myObject
[[timer userInfo] myObjectMethod];
}
停止Timer
[myTimer invalidate]; myTimer = nil;
时间
CFAbsoluteTime myCurrentTime = CFAbsoluteTimeGetCurrent();
在模拟器里测试 App 的加速度感应功能
在模拟器里可以用鼠标点击模拟 iPhone 的触摸操作，但重力感应（比如用户倾斜机身来操控飞机/赛车）怎么模拟？按住 command 再按左右方向键，就能在电脑模拟器上测试加速度感应了。
