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This article will explain in detail how to achieve secure conversion in Kotlin. The editor thinks it is very practical, so I share it with you as a reference. I hope you can get something after reading this article.

Safe Typecasting (secure conversion)

Safe type conversions are required in Android. When you first cast in Kotlin, you can do this:

Var feedFragment: FeedFragment? = supportFragmentManager .findFragmentByTag (TAG_FEED_FRAGMENT) as FeedFragment

But in fact, it can only lead to collapse. When "as" is called, it performs object conversion, but an error is reported if the converted object is "null". The correct way to use it should be "as?":

Var feedFragment: FeedFragment? = supportFragmentManager .findFragmentByTag (TAG_FEED_FRAGMENT) as? FeedFragmentif (feedFragment = = null) {feedFragment = FeedFragment.newInstance () supportFragmentManager.beginTransaction () .replace (R.id.root_fragment, feedFragment, TAG_FEED_FRAGMENT) .commit ()} this is the end of the article on "how to achieve secure conversion in Kotlin". I hope the above content can be of some help to you, so that you can learn more knowledge. if you think the article is good, please share it for more people to see.

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