android - paddingStart/Left 和 paddingEnd/Right

Question

在最近的代码编写过程中，我看到单个元素仅包含 paddingLeft/Right、paddingStart/End，以及两者。

似乎找不到任何更好的东西以及为什么。任何人有任何见解/何时使用一个或另一个或两者？

Answer 1

您需要新的开始/结束属性来创建漂亮的从右到左布局，用于人们从右到左阅读的国家/地区。

没有更好的版本，只有更新的版本。

如果要支持 Android 4.2 之前的 Android 版本，则应同时使用旧属性和新属性。如果您只想支持 Android 4.2 和更新版本，可以只使用新属性 paddingStart(而不是 paddingLeft)。

Android Developers Blog 上有很好的解释:

To take advantage of RTL layout mirroring, simply make the following changes to your app:

1. Declare in your app manifest that your app supports RTL mirroring.

   • Specifically, add android:supportsRtl="true" to the element in your manifest file.

2. Change all of your app's "left/right" layout properties to new "start/end" equivalents.

   • If you are targeting your app to Android 4.2 (the app's targetSdkVersion or minSdkVersion is 17 or higher), then you should use “start” and “end” instead of “left” and “right”. For example, android:paddingLeft should become android:paddingStart.

   • If you want your app to work with versions earlier than Android 4.2 (the app's targetSdkVersion or minSdkVersion is 16 or less), then you should add “start” and end” in addition to “left” and “right”. For example, you’d use both android:paddingLeft and android:paddingStart.