iOS UIScrollView的代理的使用及縮放時代理監聽的幾個方法

iOS UIScrollView的代理的使用及縮放時代理監聽的幾個方法

必須至少有三個步驟：

一，實現協議

二，建立關係

三，設定縮放的範圍

具體見代碼：

 

#import "ViewController.h"@interface ViewController ()  //一定要先遵守這個協議@property (weak, nonatomic) IBOutlet UIScrollView *ScrollView;@property (weak, nonatomic) IBOutlet UIImageView *minionPic;@end@implementation ViewController//滾動過程中，一直會調用該方法- (void)scrollViewDidScroll:(UIScrollView *)scrollView{    //NSLog(@"scrollViewDidScroll");}//開始滾動時調用該方法，在拖拽一次，該方法只調用一次且為最初開始時調用一次-(void)scrollViewWillBeginDragging:(UIScrollView *)scrollView{    //NSLog(@"scrollViewWillBeginDragging");}//當使用者開始縮放動作時代理要觸發的事件- (void)scrollViewWillBeginZooming:(UIScrollView *)scrollView withView:(UIView *)view{    NSLog(@"scrollViewWillBeginZooming");}//當使用者縮放時，要設定綻放哪個View？- (UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView{    return self.minionPic;}- (void)viewDidLoad {        [super viewDidLoad];        //設定ScrollView的內容大小contentSize    self.ScrollView.contentSize= self.minionPic.frame.size;    //綁定代理，建立ScrollView與代理的關係    self.ScrollView.delegate = self;        //設定縮放的範圍    self.ScrollView.minimumZoomScale = 0.2;    self.ScrollView.maximumZoomScale =2.0;                // Do any additional setup after loading the view, typically from a nib.}- (void)didReceiveMemoryWarning {    [super didReceiveMemoryWarning];    // Dispose of any resources that can be recreated.}@end