Question

我已经通过这样的代码创建了图像视图 -

- (void)viewDidLoad
{
  [super viewDidLoad];
  // Do any additional setup after loading the view, typically from a nib

  UIImageView *dot =[[UIImageView alloc] initWithFrame:CGRectMake(50,50,20,20)];
  dot.image=[UIImage imageNamed:@"draw.png"];
  [self.view addSubview:dot];

}

我想向此UIImageView添加用户互动，然后在点击时为此UIImageView创建一个选择器或操作，该如何完成？

Answer 1

试试这样： -

UIImageView *dot =[[UIImageView alloc] initWithFrame:CGRectMake(50,50,20,20)];
dot.image=[UIImage imageNamed:@"draw.png"];
[self.view addSubview:dot];

1）要实现所需的触摸次数为1，请参阅： -

UITapGestureRecognizer *doubleTapRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(scrollViewDoubleTapped:)];
doubleTapRecognizer.numberOfTapsRequired = 2;
doubleTapRecognizer.numberOfTouchesRequired = 1;
[dot addGestureRecognizer:doubleTapRecognizer];

- (void)doubleTapped:(UITapGestureRecognizer*)recognizer
{

}

2）要实现所需的触摸次数为2，请参阅： -

UITapGestureRecognizer *twoFingerTapRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(scrollViewTwoFingerTapped:)];
twoFingerTapRecognizer.numberOfTapsRequired = 1;
twoFingerTapRecognizer.numberOfTouchesRequired = 2;
[dot addGestureRecognizer:twoFingerTapRecognizer];

- (void)twoFingerTapped:(UITapGestureRecognizer*)recognizer
{

}

Answer 2

这取决于你想要达到的行动类型。一般来说，您使用的是UIGestureRecognizer。例如，如果您希望图像响应轻击手势，那么您将拥有以下内容 - （void）viewDidLoad { [super viewDidLoad]; //在加载视图后进行任何其他设置，通常是从笔尖 dotArray = [NSMutableArray alloc] init]; UITapGestureRecognizer * tapGesture = [[UITapGestureRecognizer alloc] initWithTarget：self action：@selector（handleTapGesture：）];

  for(int i = 0; i< 30; i++) {
     UIImageView *dot =[[UIImageView alloc] ...
     dot.image=[UIImage imageNamed:@"draw.png"];
     dot.tag = i; //identify dot image.
     [self.view addSubview:dot];
     [dotArray addObject:dot];
     [dot addGestureRecognizer:tapGesture];
     ...
  }

  [tapGesture release];
}

然后处理轻击手势的方法......

-(void)handleTapGesture:(id)sender {
  UITapGestureRecognizer * tapGesture = (UITapGestureRecognizer*)sender;
  for(int i = 0; i<[dotArray count]; i++) {
     UIImageView * dot = (UIImageView*)[dotArray objectAtIndex:i];
     if(dot.tag == [tapGesture view].tag) {
       //fade out animation
       [UIView beginAnimations:nil context:NULL];
       [UIView setAnimationDuration:0.5f];
       dot.alpha = 0.0f;
       [UIView commitAnimations];
}

要使其工作，您需要创建一个点数组并将其声明为实例变量，否则该方法无法访问该点。

Answer 3

谢谢大家的帮助，我把每个人的答案放在一起，并把它作为我的最终代码。

 //
    //  ViewController.m
    //  InvaderRush
    //
    //  Created by Ajay Venkat on 13/12/2014.
    //  Copyright (c) 2014 AJTech. All rights reserved.
    //

    #import "ViewController.h"

    @interface ViewController ()
    {
        NSArray *dotArray;

    }
    @end

    @implementation ViewController
    - (void)viewDidLoad {

        UIImageView *dot =[[UIImageView alloc] initWithFrame:CGRectMake(50,50,100,100)];
        dot.image=[UIImage imageNamed:@"invader.jpg"];
        [self.view addSubview:dot];
        dot.tag = 1; //identify dot image.


        UITapGestureRecognizer *doubleTapRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(doubleTapped:)];
        doubleTapRecognizer.numberOfTouchesRequired = 1;
        [dot addGestureRecognizer:doubleTapRecognizer];
            dot.userInteractionEnabled = YES;
       NSMutableArray *images =[[NSMutableArray alloc] initWithObjects: dot,nil];


    }

    - (void)didReceiveMemoryWarning {
        [super didReceiveMemoryWarning];
        // Dispose of any resources that can be recreated.
    }

    -(void)doubleTapped:(id)sender {
        UIGestureRecognizer *recognizer = (UIGestureRecognizer*)sender;
        UIImageView *imageView = (UIImageView *)recognizer.view;

        if(imageView.tag==1) {
            [imageView setImage:[UIImage imageNamed:@"space_invader.jpg"]];
        }
    }

    -(void)handleTapGesture:(id)sender {
       }
    @end

将操作添加到以编程方式创建的ImageView

3 个答案: