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AnimatedVisibility 与 Crossfade

为显示状态和内容切换添加动画。

AnimatedVisibility 与 Crossfade 是 CoddyKit 上的免费 Jetpack Compose Academy 课时。这是第 2 节课，共 4 节。你可以在下方免费阅读本课时的完整内容 — 然后在浏览器中使用内置代码编辑器和全天候 AI 导师进行实践。这是 Jetpack Compose Academy 学习路径的一部分，你的进度在网页和 CoddyKit 应用中同步。 Jetpack Compose Academy 课程共包含 4 节课。

本课时的部分内容尚未翻译，以英文显示。

Animating What Appears

Sometimes you want content to slide or fade in rather than pop. AnimatedVisibility animates a Composable as it enters and exits the screen. ✨

Wrap What You Show

Give AnimatedVisibility a boolean and a content lambda. When the boolean flips, it animates that content in or out for you.

AnimatedVisibility(visible = show) {
  Text("Hello!")
}

Default Enter and Exit

Out of the box it uses a gentle fade plus expand and shrink. The element appears and disappears smoothly without any extra configuration.

Customize the Entrance

Set the enter parameter to choose how content arrives. Combine transitions like fadeIn and slideInVertically with the plus operator.

enter = fadeIn() + slideInVertically()

Customize the Exit

The exit parameter controls how content leaves. You can mirror the entrance or pick a different effect like shrinkOut for variety.

exit = fadeOut() + shrinkVertically()

Slide, Expand, Scale

Compose ships many transitions: slideIn, expandHorizontally, scaleIn, and their exit pairs. Mix them to design exactly the motion you want.

Swapping Content Smoothly

To replace one Composable with another, reach for Crossfade. It fades the old content out while the new content fades in. 🔀

Crossfade on a Key

Give Crossfade a targetState. Whenever that value changes, it animates between the content produced for the old and new states.

Crossfade(targetState = screen) { current ->
  ScreenFor(current)
}

Great for Tabs and Screens

Crossfade shines when switching between distinct views, like loading versus loaded states or two tabs, giving a polished blend instead of a jarring swap.

Tune the Crossfade Timing

Pass an animationSpec to Crossfade to slow down or speed up the blend. A longer tween makes the transition feel softer and more deliberate.

Crossfade(state, animationSpec = tween(700)) { ... }

Pick the Right Tool

Use AnimatedVisibility to show or hide one thing, and Crossfade to swap between alternatives. Each solves a different appearance problem.

Quick Check

Which Composable smoothly swaps one piece of content for another?

Recap: Enter, Exit, Swap

You now animate appearance with AnimatedVisibility and blend between views with Crossfade, customizing enter, exit, and timing. 🎉

常见问题解答

「AnimatedVisibility 与 Crossfade」课时是免费的吗？

是的 — 「AnimatedVisibility 与 Crossfade」的完整文本可在网页上免费阅读。要进行交互式练习（内置代码编辑器和全天候 AI 导师）并解锁 Jetpack Compose Academy 课程的其余内容，请升级到 CoddyKit PRO。 Jetpack Compose Academy 课程共包含 4 节课。

「AnimatedVisibility 与 Crossfade」这节课中我会学到什么？

为显示状态和内容切换添加动画。你通过在浏览器中直接运行的动手代码来练习 Jetpack Compose Academy，全天候 AI 导师会在你学习这节课的过程中回答你的问题。

学习 Jetpack Compose Academy 需要有经验吗？

无需任何先前经验。CoddyKit 上的 Jetpack Compose Academy 课程适合初学者到高级学习者，你可以从这里开始或从头开始，按照自己的节奏学习。这是第 2 节课，共 4 节。

「AnimatedVisibility 与 Crossfade」课时需要多长时间？

大多数 CoddyKit 课程大约需要 5–10 分钟。每节课都很精短且互动，所以你能稳步进步，并在网页和应用中从离开的地方继续。

我能在这节 Jetpack Compose Academy 课中编写并运行代码吗？

能。每节 Jetpack Compose Academy 课都包含内置代码编辑器，你可以在浏览器中直接编写并运行真实代码，并获得即时 AI 反馈 — 无需本地设置。

此课程中的所有课时

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