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ContentScale 与裁剪

整齐地适配、填充和裁剪图像。

ContentScale 与裁剪 是 CoddyKit 上的免费 Jetpack Compose Academy 课时。这是第 3 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。

When Image and Box Disagree

Your image has its own aspect ratio, but your layout slot has another. ContentScale decides how the picture fits into that space.

The Aspect Ratio Problem

Force a wide photo into a square and it can stretch or squash. ContentScale gives you sane rules so pictures never look distorted by accident.

Crop Fills and Trims

The most common choice is ContentScale.Crop. It fills the whole slot and trims any overflow, so the frame is always full with no gaps.

Image(painter = p, contentDescription = null,
    contentScale = ContentScale.Crop)

Fit Shows Everything

ContentScale.Fit shrinks the image until it all fits inside the slot. Nothing is cut off, but you may see empty space on two sides.

FillBounds Can Distort

ContentScale.FillBounds stretches the image to fill both dimensions exactly. It guarantees no gaps but will warp the aspect ratio.

Width or Height Only

Need to fill just one axis? FillWidth and FillHeight scale to match that single dimension while keeping the ratio.

Inside Crops, None Does Not

Inside only shrinks when too big and never enlarges, while None draws at original size, cropping if it overflows.

Crop Needs a Bounded Size

Crop only has an effect when the Image has fixed bounds. Give it a size or fillMaxWidth with a height, or there is nothing to crop into.

Image(painter = p, contentDescription = null,
    modifier = Modifier.size(120.dp), contentScale = ContentScale.Crop)

Align Within the Frame

When Fit leaves empty space, the alignment argument decides where the image sits, such as Center or TopStart.

Image(painter = p, contentDescription = null, alignment = Alignment.TopCenter)

Crop for Thumbnails

Thumbnails and avatars almost always use Crop. It guarantees a clean, gap-free tile no matter the source photo dimensions.

Pick by Intent

Choose by what matters: use Fit when the whole image must be visible, and Crop when a full, edge-to-edge frame matters more.

Quick Check

You want an avatar tile that is always completely filled with no empty space. Which ContentScale fits best?

Recap: Scaling Images

You can now choose ContentScale wisely: Crop to fill, Fit to show all, and align the result. Next: clipping into shapes! 🔲

常见问题解答

「ContentScale 与裁剪」课时是免费的吗？

是的 — 「ContentScale 与裁剪」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。

「ContentScale 与裁剪」这节课中我会学到什么？

整齐地适配、填充和裁剪图像。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 3 节课，共 4 节。

「ContentScale 与裁剪」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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