我找到了一个简单的解决办法。 使用com.google.android.material:material:1.6.1

class MyBottomSheet: BottomSheetDialogFragment() {
    
      override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
            super.onViewCreated(view, savedInstanceState)
            disableShapeAnimation()
        }
    
      @SuppressLint("RestrictedApi", "VisibleForTests")
      private fun disableShapeAnimation() {
            try {
                val dlg = dialog as BottomSheetDialog
                dlg.behavior.disableShapeAnimations()
            } catch (ex: Exception) {
                Log.e("BaseBottomSheet", "disableShapeAnimation Exception:", ex)
            }
        }
}

Koma Yip回答的另一个问题对我有用，你应该试试。

在drawable中创建一个xml，比如dialog_bg.xml <？XML版本="1.0"编码="utf-8"?> <形状xmlns: android = " http://schemas.android.com/apk/res/android " > <固体android:颜色= " @color /白色" / > <corners android:半径="30dp" /> <填充 android:左= " 10 dp” android:顶级= " 10 dp” android:对= " 10 dp” android:底部= " 10 dp " / > < / >形状

把这个放在你的布局XML根节点中:

将其设置为布局XML中的背景 android:背景= " @drawable / dialog_bg”

在onCreateView()中放入:

将对话框的背景设置为透明 dialog.getWindow()。setBackgroundDrawable(新ColorDrawable (Color.TRANSPARENT));

底部对话框设置了默认的白色背景色，这就是为什么角落是不可见的，为了显示它们，你需要通过覆盖底部对话框的风格使对话框的背景透明。

在res/values/styles/styles.xml中定义此样式

<style name="BottomSheetDialog" parent="Theme.Design.Light.BottomSheetDialog">
    <item name="bottomSheetStyle">@style/bottomSheetStyleWrapper</item>
</style>

<style name="bottomSheetStyleWrapper" parent="Widget.Design.BottomSheet.Modal">
    <item name="android:background">@android:color/transparent</item>
</style>

并将此样式设置为您的BottomSheetDialog

View view = getLayoutInflater().inflate(R.layout.chooser_bottom_sheet, null);
BottomSheetDialog dialog = new BottomSheetDialog(this,R.style.BottomSheetDialog); // Style here
dialog.setContentView(view);
dialog.show();

如果您正在使用材质组件主题，您可以通过将背景颜色设置为透明，然后将布局的背景设置为四舍五入来覆盖BottomSheetDialog的默认行为。

    <style name="Theme.MyApp" parent="Theme.MaterialComponents.DayNight.DarkActionBar">
        <!-- Customize your theme here. -->
        <item name="bottomSheetDialogTheme">@style/BottomSheetDialog</item>
    </style>

    <style name="BottomSheetDialog" parent="ThemeOverlay.MaterialComponents.BottomSheetDialog">
        <item name="bottomSheetStyle">@style/bottomSheetStyleWrapper</item>
    </style>

    <style name="bottomSheetStyleWrapper" parent="Widget.MaterialComponents.BottomSheet.Modal">
        <item name="android:backgroundTint">@android:color/transparent</item>
    </style>

rounded_corner.xml:

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="rectangle">
    <solid android:color="@color/white"/>
    <corners android:topLeftRadius="26dp"
        android:topRightRadius="26dp"/>

</shape>

然后将形状应用到你的底部表格根布局的背景:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@drawable/rounded_corner">

    <!-- 
       other layout components
     -->

</LinearLayout>

注意，如果你在底部表单布局中使用Webview这样的组件，你可能无法实现预期的圆角，因为Webview有一个默认的白色背景。在这种情况下，你可以像这样简单地删除背景:

webView.setBackgroundColor(0);

我知道这个问题已经有了一个公认的答案。我想要记录我经历的问题，以及我最终是如何让它工作的，这样它对未来的人是有用的。

Firstly, I was using Theme.AppCompat.Light.DarkActionBar as the parent for our AppTheme. This meant @Gabriele Mariotti solution kept crashing with the error Could not inflate Behavior subclass com.google.android.material.bottomsheet.BottomSheetBehavior. I fixed this by simply changing the parent to Theme.MaterialComponents.Light.DarkActionBar. This did not affect our theme in any way but the RTE was gone. You can also fix this issue by simply including the require items to your style. But I didn't bother figuring out which styles were required by BottomSheetBehavior.

其次，尝试我可能，但我不能得到实际的框架布局(这是BottomSheetDialogFragment)使用圆角。我意识到，将此设置为图像Drawable工作，但不适用于形状或@null。事实证明，这是因为我使用的LinearLayout有一个定义的背景。这覆盖了样式中的任何背景。去掉它最终会产生圆角。

此外，我不需要设置任何背景形状来圆角。@Gabriele Mariotti的解决方案在我做出上述更改后立即起作用。然而，为了设置我想要的背景色，我必须覆盖“backgroundTint”项。

PS:我是Android开发的新手，我正在维护一个旧的应用程序，这是我们学院内部使用的。我不是很熟悉Android的布局系统或材料库。我想这就是为什么我花了3天时间才弄明白。我希望这对将来的人有用。

Create a shape drawable .. which we will use as background for bottom sheet . Provide the appropriate value for radius of top left and right corner . <?xml version="1.0" encoding="utf-8"?> <shape xmlns:android="http://schemas.android.com/apk/res/android" android:shape="rectangle"> <corners android:topLeftRadius="24dp" android:topRightRadius="24dp" /> <padding android:top="2dp" /> <solid android:color="@color/white" /> </shape> Now create style for " Bottom sheet dialog fragment " <style name="BottomSheet" parent="@style/Widget.Design.BottomSheet.Modal"> <item name="android:background">@drawable/drawable_bottomsheet_background</item> </style> <style name="BaseBottomSheetDialog" parent="@style/Theme.Design.Light.BottomSheetDialog"> <item name="android:windowIsFloating">false</item> <item name="bottomSheetStyle">@style/BottomSheet</item> </style> <style name="BottomSheetDialogTheme" parent="BaseBottomSheetDialog" /> Now create a custom class that will extend BottomSheetDilogFragment ,where you provide your style . open class CustomRoundBottomSheet : BottomSheetDialogFragment() { override fun getTheme(): Int = R.style.BottomSheetDialogTheme override fun onCreateDialog(savedInstanceState: Bundle?): Dialog = BottomSheetDialog(requireContext(), theme) } Now use this class wherever you want to have round corner bottom sheet . eg class BottomSheetSuccess : CustomRoundBottomSheet() { override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? { return inflater.inflate(R.layout.bottomsheet_shopcreate_success, container, false) } override fun onViewCreated(view: View, savedInstanceState: Bundle?) { super.onViewCreated(view, savedInstanceState) } }