我什么时候应该打电话给超级? [英] When should I call super?

问题描述

[super ... any method name] 的最佳用法是什么.最近我发现在 dealloc 中 [super dealloc] 必须站在同一端.因为如果我们在 [super dealloc] 之后设置它，任何之前没有使用过的变量都会被垃圾填充.这是一种罕见的事情，但它是可能的.在此之后，我们的应用程序将崩溃.

What is the best using of [super ... any method name]. Recently I have found out that In dealloc the [super dealloc] must stand in the same end. Because any variable what didn't use before can be filled by garbage if we set it after [super dealloc] It's a rare thing, but it's possible. After this we will have crash in our app.

那么什么是超级方法的最佳用途，例如什么是最好的用于-(void)viewWillAppear:(BOOL)animated.[super viewWillAppear:(BOOL)animated] 正文开头或结尾的最佳位置在哪里?

So what is the best using of super method, for example what is best using for -(void)viewWillAppear:(BOOL)animated. Where is the best place for [super viewWillAppear:(BOOL)animated] in the begin of body or in the end?

推荐答案

通常的经验法则是，当你覆盖一个进行某种初始化的方法时，你首先调用 super 然后做你的事情.当你重写某种拆卸方法时，你调用 super last :

The usual rule of thumb is that when you are overriding a method that does some kind of initialization, you call super first and then do your stuff. And when you override some kind of teardown method, you call super last:

- (void) setupSomething {
    [super setupSomething];
    …
}

- (void) tearDownSomething {
    …
    [super tearDownSomething];
}

第一类是像 init...、viewWillAppear、viewDidLoad 或 setUp 这样的方法.第二个是诸如 dealloc、viewDidUnload、viewWillDisappear 或 tearDown 之类的东西.这不是硬性规定，它只是遵循方法所做的事情.

The first kind are methods like init…, viewWillAppear, viewDidLoad or setUp. The second are things like dealloc, viewDidUnload, viewWillDisappear or tearDown. This is no hard rule, it just follows from the things the methods do.

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