以编程方式在BottomSheetDialogFragment中设置Peek高度

Question

我有一个BottomSheetDialogFragment，我希望能在任何屏幕上显示它。我已经花了一天的时间尝试编程更改该表的peek高度，但似乎没有任何变化。

这是我的布局，bottom_sheet.xml：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">

    <LinearLayout
        android:id="@+id/bottom_sheet"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="@color/white"
        android:orientation="vertical"
        app:behavior_hideable="true"
        app:behavior_peekHeight="96dp"
        app:layout_behavior="@string/bottom_sheet_behavior">

        <androidx.core.widget.NestedScrollView
            android:id="@+id/content"
            android:layout_width="match_parent"
            android:layout_height="wrap_content" />

    </LinearLayout>

</LinearLayout>

您会注意到我有一个空的NestedScrollView。这是因为当我在不同的屏幕上显示底部表时，我使内容可定制，因此我通过代码加载自定义布局。

这是我的片段类：

public class BottomSheetFragment extends BottomSheetDialogFragment {

    private LinearLayout bottomSheet;
    private NestedScrollView contentView;

    public BottomSheetFragment() {

    }

    @Override
    public void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
    }

    @Nullable
    @Override
    public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        return inflater.inflate(R.layout.bottom_sheet, container, false);
    }

    @Override
    public void onViewCreated(@NotNull View view, Bundle savedInstanceState) {
        super.onViewCreated(view, savedInstanceState);

        bottomSheet = view.findViewById(R.id.bottom_sheet);
        contentView = view.findViewById(R.id.content);
    }

    // Set the layout of the NestedScrollView by passing a layout ID
    public void setLayout(int layoutId) {
        if (contentView != null) {
            contentView.removeAllViews();

            View view = getLayoutInflater().inflate(layoutId, contentView, false);

            if (view != null) {
                contentView.addView(view);
            }
        }
    }
}

然后，在我想显示底部表单的地方，我这样做：

BottomSheetFragment bottomSheetFragment = new BottomSheetFragment();
bottomSheetFragment.show(getSupportFragmentManager(), bottomSheetFragment.getTag());

我希望表格的最高点距离屏幕顶部为64dp。 我应该在哪里以编程方式实现这一点？

我还发现，即使我在布局中更改app：behavior_peekHeight =“96dp”的值为500dp之类的值，当我显示表格时仍然没有任何变化。

- user9846951

Answer 1

你的底部弹出表中没有视图元素，这就是为什么当你试着调整peekheight时看不到任何变化。

给底部弹出表设置一些高度以便查看更改。 例如，如果你设置高度为300，你将清楚地看到peek height生效。

例如，

<LinearLayout
            app:layout_constraintLeft_toLeftOf="parent"
            app:layout_constraintTop_toTopOf="parent"
            android:layout_width="match_parent"
            android:layout_height="300dp"
            android:background="@color/colorPrimary"
            android:orientation="vertical"
            android:id="@+id/bottom_sheet"
            app:layout_behavior="@string/bottom_sheet_behavior"
            app:behavior_peekHeight="96dp"
            app:behavior_hideable="true">

            <androidx.core.widget.NestedScrollView
                android:id="@+id/content"
                android:layout_width="match_parent"
                android:layout_height="wrap_content" />

        </LinearLayout>

将导致结果为

以编程方式设置peekheight

首先，您必须将您的底部工作表放置在坐标布局中，就像这样

<androidx.coordinatorlayout.widget.CoordinatorLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content">
        <LinearLayout
            app:layout_constraintLeft_toLeftOf="parent"
            app:layout_constraintTop_toTopOf="parent"
            android:layout_width="match_parent"
            android:layout_height="300dp"
            android:background="@color/colorPrimary"
            android:orientation="vertical"
            android:id="@+id/bottom_sheet"
            app:layout_behavior="@string/bottom_sheet_behavior"
            app:behavior_peekHeight="96dp"
            app:behavior_hideable="true">

            <androidx.core.widget.NestedScrollView
                android:id="@+id/content"
                android:layout_width="match_parent"
                android:layout_height="wrap_content" />

        </LinearLayout>
    </androidx.coordinatorlayout.widget.CoordinatorLayout>

在你的班级里，你这样做。

@Override
    public void onViewCreated(final View view, @Nullable Bundle savedInstanceState) {
        super.onViewCreated(view, savedInstanceState);
        View bottomSheet = view.findViewById(R.id.bottom_sheet);
        BottomSheetBehavior behavior = BottomSheetBehavior.from(bottomSheet);
        behavior.setPeekHeight(150); 
    }

- Usman Zafer

---

有没有一种方法可以不使用 Coordinator Layout 来实现它？我发现如果使用它，会破坏其他东西。 - user9846951

不完全是。您必须坚持使用CoordinatorLayout。根据文档，BottomSheetBehavior是CoordinatorLayout的子视图的交互行为插件。 - Usman Zafer

CoordinatorLayout 可以在不通过编程方式改变高度的情况下适用于此高度。谢谢。 - Dhanunjaya

Answer 2

你可以在 BottomSheetShow 上设置状态 STATE_EXPANDED。这是我的工作代码片段。

@Override
    public Dialog onCreateDialog(Bundle savedInstanceState) {

        BottomSheetDialog dialog = (BottomSheetDialog) super.onCreateDialog(savedInstanceState);

        dialog.setOnShowListener((DialogInterface.OnShowListener) dialog1 -> {
            BottomSheetDialog d = (BottomSheetDialog) dialog1;
            FrameLayout bottomSheet = (FrameLayout) d.findViewById(com.google.android.material.R.id.design_bottom_sheet);
            if (bottomSheet != null)
                BottomSheetBehavior.from(bottomSheet).setState(BottomSheetBehavior.STATE_EXPANDED);
        });

        return dialog;
    }

- Amrish Kakadiya

Answer 3

为了以编程方式设置最大高度，您可以：

1. 在您的 BottomSheetDialogFragment 中覆盖 onCreateDialog
2. 强制转换为 BottomSheetDialog
3. 在 behavior（BottomSheetBehavior）上调用setPeekHeight（int，boolean）

override fun onCreateDialog(savedInstanceState: Bundle?): Dialog {
    return super.onCreateDialog(savedInstanceState).apply {
        (this as? BottomSheetDialog)
                ?.behavior
                ?.setPeekHeight(BottomSheetBehavior.PEEK_HEIGHT_AUTO, true)
    }
}

BottomSheetBehavior.PEEK_HEIGHT_AUTO 设置为 16:9 的比例，true 表示是否进行动画。

- Shazbot

Answer 4

你可以通过在BottomSheetFragment中覆盖OnCreateDialog方法并获取其引用来设置底部工作表的最小高度。

public class BottomSheetFragment extends BottomSheetDialogFragment {

    private LinearLayout bottomSheet;
    private NestedScrollView contentView;

    public BottomSheetFragment() {

    }

    @Override
    public void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
    }

    @Nullable
    @Override
    public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        return inflater.inflate(R.layout.bottom_sheet, container, false);
    }

    @Override
    public void onViewCreated(@NotNull View view, Bundle savedInstanceState) {
        super.onViewCreated(view, savedInstanceState);

        bottomSheet = view.findViewById(R.id.bottom_sheet);
        contentView = view.findViewById(R.id.content);
    }

    /**
     * 
     * Your code to modify the bottom sheet behavior to set peek height which will be used in collapsed state
     * Here I set it to 80 percent of height of my screen
     * You can directly setPeekHeight() to your requirement
     */
    @NonNull @Override
    public Dialog onCreateDialog(Bundle savedInstanceState) {

        dialog = (BottomSheetDialog) super.onCreateDialog(savedInstanceState);

        dialog.setOnShowListener(new DialogInterface.OnShowListener() {
            @Override
            public void onShow(DialogInterface dialog) {
                BottomSheetDialog bottom_dialog = (BottomSheetDialog) dialog;

                FrameLayout bottomSheet = (FrameLayout) bottom_dialog.findViewById(com.google.android.material.R.id.design_bottom_sheet);
                assert bottomSheet != null;
                //BottomSheetBehavior.from(bottomSheet).setState(BottomSheetBehavior.STATE_EXPANDED);
                DisplayMetrics displayMetrics = requireActivity().getResources().getDisplayMetrics();
                int height = displayMetrics.heightPixels;
                int maxHeight = (int) (height*0.80);
                BottomSheetBehavior.from(bottomSheet).setPeekHeight(maxHeight);
            }
        });

        return dialog;
    }

    // Set the layout of the NestedScrollView by passing a layout ID
    public void setLayout(int layoutId) {
        if (contentView != null) {
            contentView.removeAllViews();

            View view = getLayoutInflater().inflate(layoutId, contentView, false);

            if (view != null) {
                contentView.addView(view);
            }
        }
    }
}

- GowthamGnanajothi

Answer 5

你需要重写 onCreateDialog 方法，并将 super.onCreateDialog(savedInstanceState) 强制转换为 BottomSheetDialog，该对话框包含了方法 behavior.setPeekHeight(Int)

override fun onCreateDialog(savedInstanceState: Bundle?): Dialog {
    return (super.onCreateDialog(savedInstanceState) as BottomSheetDialog).apply {
      behavior.setPeekHeight(resources.displayMetrics.heightPixels / 2)
    }
}

- Aziz