为什么Apple以这种方式创建它的视图 [英] Why does Apple create its views this way

问题描述

希望修复我的另一个帖子的错误我想知道为什么苹果写这个（为它的元素示例）

In the hope of fixing a bug of mine from another post i would like to know why apple writes this (for it's Elements example)

UIView *localContainerView = [[UIView alloc] initWithFrame:[[UIScreen mainScreen] applicationFrame]];
self.containerView = localContainerView;
[localContainerView release];

而不是更简单的方法：

containerView = [[UIView alloc] initWithFrame:[[UIScreen mainScreen] applicationFrame]];

推荐答案

self.containerView = 实际上是 [self setContainerView：] 之前分配新值。当你直接赋值时，你必须知道该成员没有引用任何东西，例如因为你刚刚释放它或检查一个 nil 值。

self.containerView = is actually [self setContainerView:], which will usually release any previous value before assigning a new value. When you assign directly, you have to know that the member was not holding a reference to anything, for example because you just released it or checked for a nil value.

[self setContainerView：] 还可以处理任何其他处理。

[self setContainerView:] can also handle any additional processing.

这篇关于为什么Apple以这种方式创建它的视图的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！