iOS开发基础知识--碎片25
iOS开发基础知识--碎片25
1:使用@protocol实现delegate和datasource模式
#import <UIKit/UIKit.h> @protocol MyViewDataSource,MyViewDelegate; @interface myView : UIView<UIAlertViewDelegate> @property(nonatomic,assign)id<MyViewDelegate> myViewDelegate; @property(nonatomic,assign)id<MyViewDataSource> myViewDataSource; -(void)myShowAlert; @end @protocol MyViewDelegate <NSObject> @optional -(void)alertDidPop:(myView *)myView; -(void)alertConfirmShow:(myView *)myView clickedButtonAtIndex:(NSInteger)buttonIndex; @end @protocol MyViewDataSource <NSObject> @optional -(NSString *)textOfAlert:(myView *)myView; @required - (NSUInteger)numberOfItemsInMyView:(myView *)myView; @required @end
#import "myView.h" @implementation myView -(void)myShowAlert { UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"测试实例" message:@"message" delegate:self cancelButtonTitle:@"取消" otherButtonTitles:@"确定",nil]; alert.message = [self.myViewDataSource textOfAlert:self]; [alert show]; } - (void)didPresentAlertView:(UIAlertView *)alertView { [self.myViewDelegate alertDidPop:self]; } -(void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex { [self.myViewDelegate alertConfirmShow:self clickedButtonAtIndex:buttonIndex]; } @end
使用方式:
#import "myView.h" @interface ViewController ()<MyViewDataSource,MyViewDelegate> @end
- (void)viewDidLoad { [super viewDidLoad]; myView *myVw = [[myView alloc]initWithFrame:CGRectMake(0, 0, 320, 460)]; myVw.myViewDataSource = self; myVw.myViewDelegate = self; [self.view addSubview:myVw]; [myVw myShowAlert]; }
代理实现的方法: - (void)alertDidPop:(UIView *)myView { myView.backgroundColor = [UIColor yellowColor]; } -(NSString *)textOfAlert:(myView *)myView { return @"信息"; } -(void)alertConfirmShow:(myView *)myView clickedButtonAtIndex:(NSInteger)buttonIndex { NSLog(@"你选中了%d",buttonIndex); }
2:动画 UIView animateWithDuration 使用详解
+ (void)animateWithDuration:(NSTimeInterval)duration animations:(void (^)(void))animations + (void)animateWithDuration:(NSTimeInterval)duration animations:(void (^)(void))animations completion:(void (^)(BOOL finished))completion + (void)animateWithDuration:(NSTimeInterval)duration delay:(NSTimeInterval)delay options:(UIViewAnimationOptions)options animations:(void (^)(void))animations completion:(void (^)(BOOL finished))completion
duration为动画持续的时间。animations为动画效果的代码块
可设动作属性:
- frame
- bounds
- center
- transform
- alpha
- backgroundColor
- contentStretch
例如一个视图淡出屏幕,另外一个视图出现的代码
[UIView animateWithDuration:1.0 animations:^{ firstView.alpha = 0.0; secondView.alpha = 1.0; }];
连续动画(可以在completion代码块中添加动画):
[UIView animateWithDuration:2.0 animations:^{ oldImageView.alpha = 0.0; newImageView.alpha = 1.0; //imageView.center = CGPointMake(500.0, 512.0); } completion:^(BOOL finished){ [UIView animateWithDuration:4.0 animations:^{ newImageView.center = CGPointMake(500.0, 512.0); }]; }];
从上往下一个动作(默认是左上角,把要改变的值放在animations里):
-(UIView *)myView { if (!_myView) { _myView=[[UIView alloc]initWithFrame:CGRectZero]; _myView.backgroundColor=[UIColor redColor]; } return _myView; } - (IBAction)BtnAction:(id)sender { self.myView.frame = CGRectMake(0,44, 320, 0); [self.view addSubview:self.myView]; [UIView animateWithDuration:0.3 animations:^{ self.myView.backgroundColor=[UIColor redColor]; self.myView.frame = CGRectMake(0,44, 320, 100); } completion:^(BOOL finished) { }]; }
3:UIView 的旋转和缩放
label.transform = CGAffineTransformMakeRotation(90 *M_PI / 180.0); //顺时针旋转 90度 label.transform = CGAffineTransformMakeRotation(180 *M_PI / 180.0); //顺时针 旋转180度 label.transform = CGAffineTransformMakeRotation(270 *M_PI / 180.0); //顺时针旋转270度 CGAffineTransform transform = label.transform; transform = CGAffineTransformScale(transform, 2,0.5);//前面的2表示横向放大2倍,后边的0.5表示纵向缩小一半 label.transform = transform;