iphone - 带有可重新排列按钮的 UIScrollView

Question

我需要实现一个带有多个按钮的弹出菜单。我已经创建了弹出窗口并向其中动态添加了按钮。现在我需要像 iPhone 主屏幕那样重新排列按钮。当出现长按手势时，按钮需要使用关闭按钮开始动画(就像我们尝试从手机中删除应用程序时出现的那样)。此外，我需要通过拖动来重新排列按钮的位置。我已经为按钮的外观和关闭按钮添加了动画，但我正在努力寻找一种重新排列按钮位置的方法。我搜索了很多，发现了很多关于此功能的链接，但其中大部分都非常冗长和复杂。我只想要一个可以快速实现的快速/简单的。任何想法家伙？

Answer 1

我有同样的问题，我用下面的代码解决了我的问题。

1) 从文档文件夹中获取所有图像
2) 在scrollview中设置
3) 将 UILongPressGestureRecognizer 放在 Imageview 上。并显示十字按钮。
4) 如果删除则重复步骤 2 到 4。

无需排列整个项目，只需从 ScrollView 中删除所有项目并重新填充即可。

    //Document Directory
    #define kAppDirectoryPath   NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES)

    #pragma mark - File Functions - Document/Cache Directory Functions
    - (void)createDocumentDirectory:(NSString*)pStrDirectoryName
    {
        NSString *dataPath = [self getDocumentDirectoryPath:pStrDirectoryName];

        if (![[NSFileManager defaultManager] fileExistsAtPath:dataPath])
            [[NSFileManager defaultManager] createDirectoryAtPath:dataPath withIntermediateDirectories:NO attributes:nil error:NULL];
    }

    - (NSString*)getDocumentDirectoryPath:(NSString*)pStrPathName
    {
        NSString *strPath = @"";
        if(pStrPathName)
            strPath = [[kAppDirectoryPath objectAtIndex:0] stringByAppendingPathComponent:pStrPathName];

        return strPath;
    }



    -(void)setScrollviewItem {

        NSArray* subviews = [[NSArray alloc] initWithArray: scrollObj.subviews];
        for (UIView* view in subviews) {
            if ([view isKindOfClass:[UIImageView class]]) {
                [view removeFromSuperview];
            }
            if ([view isKindOfClass:[UIButton class]]) {
                [view removeFromSuperview];
            }
        }
        [subviews release];

        [arrSaveImage removeAllObjects];  
        NSError *error = nil;
        NSArray *dirContents = [[NSFileManager defaultManager] contentsOfDirectoryAtPath:[slef getDocumentDirectoryPath:@"MyPhotos"] error:&error];// MyPhoto is my Directory Name.
        if (!error) {
            NSPredicate *predicate = [NSPredicate predicateWithFormat:@"self ENDSWITH '.png'"];
            NSArray *imagesOnly = [dirContents filteredArrayUsingPredicate:predicate];

            for (int i=0;i<[imagesOnly count]; i++) {
                [arrSaveImage addObject:[imagesOnly objectAtIndex:i]];
            }
        }

        int px=0;
        for (int i = 0; i < [arrSaveImage count]; i++) {
            UIImageView *imgBackScroll=[[UIImageView alloc] init];
            NSString *strPath=[self getDocumentDirectoryPath:@"MyPhotos"];
            strPath=[NSString stringWithFormat:@"%@/%@",strPath,[arrSaveImage objectAtIndex:i]];
            imgBackScroll.image=[UIImage imageWithData:[NSData dataWithContentsOfFile:strPath]];
            imgBackScroll.frame=CGRectMake(px+5, 10, 90, 80);
            imgBackScroll.layer.cornerRadius = 5.0;
            imgBackScroll.layer.masksToBounds = YES;
            imgBackScroll.tag=i;
            imgBackScroll.userInteractionEnabled = YES;
            [scrollObj addSubview:imgBackScroll];

            UIButton *btn=[UIButton buttonWithType:UIButtonTypeCustom];//This is your Cross delete button on corner
            //[btn setTitle:@"-" forState:UIControlStateNormal];
            [btn setImage:[UIImage imageNamed:@"CrossDelete.png"] forState:UIControlStateNormal];
            [btn addTarget:self action:@selector(deleteButton:) forControlEvents:UIControlEventTouchUpInside];
            btn.frame=CGRectMake(imgBackScroll.frame.origin.x-2, 0, 15, 15);
            btn.hidden=YES;
            btn.tag=i;

            [scrollObj addSubview:btn];


            UILongPressGestureRecognizer *longPressGesture = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(startWobbling:)];
            longPressGesture.view.tag=i;
            [imgBackScroll addGestureRecognizer:longPressGesture];

            [imgBackScroll release];
            [longPressGesture release];

            px=px+95;
        }
        scrollObj.contentSize = CGSizeMake(px, scrollObj.frame.size.height);
    }



    -(void) startWobbling:(UILongPressGestureRecognizer*)gesture{
           CGAffineTransform leftWobble = CGAffineTransformRotate(CGAffineTransformIdentity, RADIANS(-5.0));
            CGAffineTransform rightWobble = CGAffineTransformRotate(CGAffineTransformIdentity, RADIANS(5.0));

            gesture.view.transform = leftWobble;  // starting point

            [UIView beginAnimations:@"wobble" context:gesture.view];
            [UIView setAnimationRepeatAutoreverses:YES]; // important
            [UIView setAnimationRepeatCount:11];
            [UIView setAnimationDuration:0.25];
            [UIView setAnimationDelegate:self];
            [UIView setAnimationDidStopSelector:@selector(wobbleEnded:finished:context:)];

            gesture.view.transform = rightWobble; // end here & auto-reverse

            [UIView commitAnimations];

        NSArray* subviews = [[NSArray alloc] initWithArray: scrollObj.subviews];
        for (UIView* view in subviews) {

            if ([view isKindOfClass:[UIButton class]]) {
                if (view.tag==gesture.view.tag) {
                    view.hidden=NO;
                }
            }
        }
        [subviews release];
    }


    //When Delete button pressed

    -(IBAction)deleteButton:(id)sender {
        UIButton *bt=(UIButton *)sender;
     self.strDeleteFilePath=[FunctionManager getDocumentDirectoryPath:@"MyPhotos"];
        self.strDeleteFilePath=[NSString stringWithFormat:@"%@/%@",strDeleteFilePath,[arrSaveImage objectAtIndex:bt.tag]];
        UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"" message:@"Are you sure you want to delete this photo" delegate:self cancelButtonTitle:@"Delete" otherButtonTitles:@"Cancel", nil];
        [alert show];
        [alert release];
    }

    - (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex{
        if (buttonIndex == 0){
            NSFileManager *fileManager = [NSFileManager defaultManager];
            NSError *error = nil;
            if(![fileManager removeItemAtPath:self.strDeleteFilePath error:&error]) {
                NSLog(@"Delete failed:%@", error);
            } else {
                NSLog(@"image removed: %@",strDeleteFilePath);
            }
            [self setScrollviewItem];
        }
    }