Iphone 如何在数组中存储CGPoint

您好，我正在尝试将移动点存储在

NSMutableArray

中，因此我进行了如下尝试

-(void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
UITouch *move = [[event allTouches] anyObject];
    CGPoint MovePoint = [move locationInView:self.view];
if (MovePointsArray==NULL) {
        MovePointsArray=[[NSMutableArray alloc]init];
    }
    [MovePointsArray arrayWithObjects:[NSValue valueWithCGPoint:MovePoint]];
}

---

但这不起作用。如何将这些点存储在

NSMutableArray

中？您应该在最后一行中使用addObject:

-(void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
UITouch *move = [[event allTouches] anyObject];
    CGPoint MovePoint = [move locationInView:self.view];
if (MovePointsArray==NULL) {
        MovePointsArray=[[NSMutableArray alloc]init];
    }
    [MovePointsArray addObject:[NSValue valueWithCGPoint:MovePoint]];
}

---

如果要使用方法

arrayWithObjects

获取数组，还必须添加

nil

作为数组的最后一个元素

像这样：

[MovePointsArray arrayWithObjects:[NSValue valueWithCGPoint:MovePoint], nil];

但要将对象添加到现有数组中，应使用

addObject

方法

[MovePointsArray addObject:[NSValue valueWithCGPoint:MovePoint]];

---

你应该这样做：

-(void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
    UITouch *move = [[event allTouches] anyObject];
    CGPoint MovePoint = [move locationInView:self.view];

    if (MovePointsArray == NULL) {
        MovePointsArray = [[NSMutableArray arrayWithObjects:[NSValue valueWithCGPoint:MovePoint, nil];
    }
    else {
        [MovePointsArray addObject:[NSValue valueWithCGPoint:MovePoint]];
    }
}

不要忘记保留/释放阵列，因为您看不到要使用属性访问器

最好是在init方法中alloc/init数组，然后只在此处执行：

-(void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
    UITouch *move = [[event allTouches] anyObject];
    CGPoint MovePoint = [move locationInView:self.view];

    [MovePointsArray addObject:[NSValue valueWithCGPoint:MovePoint]];
}