polymer-2.x - Polymer 就绪与 connectedCallback

Question

我想知道 ready() 方法在 polymer 中的重要性是什么，这种方法的准时初始化是什么意思，以及 read( ) 和 connectedCallback() ???

Answer 1

以下应该有所帮助。

connectedCallback can be called more than once

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Generally all setup work in connectedCallback should be balanced with associated teardown work in disconnectedCallback; if not it usually means connectedCallback is the wrong place to do it

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At this point it's hard to contrive general a use case where ready is the only/best place to do work, although they do come up from time to time in very specific cases.

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ready is called only once, so work done here based on a property value may become invalidated if the property value is changed at a later point by the user

参见 https://github.com/Polymer/polymer/issues/4108#issuecomment-258983943