手指隨意移動的ICON實作

一個簡當的ICON移動，在實作中會有六個ICON，每一個都可以隨意地用手指來點選移動。

1. 開啓一個專案

2. 加入六張圖片分別當作ICON

3. 加入一個新的Class檔，作為控制圖片移動之用，此處選用UIButton

4.先針對class 的movPicture.h作修改
#import <UIKit/UIKit.h>

@interface movPicture : UIButton
{
    CGPoint beginPoint;
}

@property (nonatomic) BOOL dragEnable;

@end

5. 然後在movPicture.m加入觸控的程式碼
#import "movPicture.h"

@implementation movPicture

@synthesize dragEnable;

- (id)initWithFrame:(CGRect)frame
{
    self = [super initWithFrame:frame];
    if (self) {
        // Initialization code
    }
    return self;
}

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
    if (!dragEnable) {
        return;
    }
    UITouch *touch = [touches anyObject];
   
    beginPoint = [touch locationInView:self];
   
}

- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
    if (!dragEnable) {
        return;
    }
    UITouch *touch = [touches anyObject];
   
    CGPoint nowPoint = [touch locationInView:self];
   
    float offsetX = nowPoint.x - beginPoint.x;
    float offsetY = nowPoint.y - beginPoint.y;
   
    self.center = CGPointMake(self.center.x + offsetX, self.center.y + offsetY);
}

@end


5. 然後在mainViewController.m加上設定的程式碼
#import "mainViewController.h"
#import "movPicture.h"
@interface mainViewController ()

@end

@implementation mainViewController

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
   
    for (int i=0;i<6;i++)
    {
        movPicture *tt = [[movPicture alloc] initWithFrame:CGRectMake(i%3*120, (i/3)*120 , 100, 100)];
       
        [tt setImage:[UIImage imageNamed:[NSString stringWithFormat:@"%d.png",i+1]] forState:UIControlStateNormal];
       
        tt.dragEnable = YES;
     
        tt.tag = i;
       
        [self.view addSubview:tt];
    }
}

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

@end

6. 完成後的執行結果，每一個小圖都可以隨意用手指移動