objective-c - 拖放而不移除 UIButton

Question

我正在 iPhone 应用程序中实现拖放系统。到目前为止，我设法实现了可拖动按钮并且工作正常。这是我的代码:

首先，我将操作分配给按钮:

[button addTarget:self action:@selector(imageMoved:withEvent:) forControlEvents:UIControlEventTouchDragInside];

然后，我创建拖动:

- (IBAction) imageMoved:(id) sender withEvent:(UIEvent *) event
{
    NSLog(@"moved");
    CGPoint point = [[[event allTouches] anyObject] locationInView:self.view];
    UIControl *control = sender;
    control.center = point;
}

但是，我想要实现的是被拖动的按钮不会从它所在的位置移除。所以我想到了一个解决方案，就是创建一个类似于第一个的新按钮，然后移动这个新创建的按钮。但是我在实现最后一部分时遇到了麻烦。有什么帮助吗？非常感谢!

Answer 1

- (IBAction) imageMoved:(id) sender withEvent:(UIEvent *) event {
    NSLog(@"moved");          

    CGPoint point = [[[event allTouches] anyObject] locationInView:self.view];

    if (![self.view viewWithTag:11]) {

        NSData *archivedData = [NSKeyedArchiver archivedDataWithRootObject:(UIButton*)sender];                

        UIButton *anotherButton =(UIButton*) [NSKeyedUnarchiver unarchiveObjectWithData:archivedData];

        anotherButton.tag = 11;    


        UIImage *senderImage=[(UIButton *)sender imageForState:UIControlStateNormal];




        CGImageRef cgImage = [senderImage CGImage];


        UIImage *copyOfImage = [[UIImage alloc] initWithCGImage:cgImage];



        [anotherButton setImage:copyOfImage forState:UIControlStateNormal];

        [self.view addSubview:anotherButton];
    }

    [self.view viewWithTag:11].center = point;
}