java - Bottom Sheet 展开时最小化带有动画的底部导航栏

Question

我有一个底部导航栏和其上方的 Bottom Sheet 。 Bottom Sheet 可以扩展以填充整个屏幕，我想添加一个动画，在 Bottom Sheet 扩展时隐藏底部导航栏。下面是我的布局的屏幕截图，展开的图像显示了它当前的样子，所需的图像显示了我想要的样子。我查看了 Bottom Sheet 文档，但找不到任何有用的内容。

折叠:/image/lrqjA.png

扩展:/image/rr2K8.png

所需:/image/P8a1W.png

下面是我的布局

<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/constraintLayout"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <com.google.android.material.bottomnavigation.BottomNavigationView
        android:id="@+id/navigation_bar"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        app:backgroundTint="?attr/colorSurface"
        android:elevation="16dp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:menu="@menu/bottom_nav_menu">
    </com.google.android.material.bottomnavigation.BottomNavigationView>

    <fragment
        android:id="@+id/map"
        android:name="com.google.android.gms.maps.SupportMapFragment"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        app:cameraZoom="13.8"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        tools:context=".MainActivity" />

    <androidx.coordinatorlayout.widget.CoordinatorLayout
        android:id="@+id/coordinatorLayout"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        app:layout_constraintBottom_toTopOf="@+id/navigation_bar"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        android:elevation="16dp" >

        <include layout="@layout/bottom_sheet" />

        <LinearLayout
            android:id="@+id/floating_action_buttons"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="bottom|end"
            android:clipToPadding="false"
            android:gravity="center"
            android:orientation="vertical"
            android:padding="16dp"
            app:layout_behavior="jonathan.gpsapp.FloatingButtonBehavior">

            <com.google.android.material.floatingactionbutton.FloatingActionButton
                android:id="@+id/center_map"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_marginBottom="8dp"
                android:clickable="true"
                android:src="@drawable/ic_center"
                app:backgroundTint="?attr/colorSurface"
                app:fabSize="mini"
                app:tint="?attr/colorPrimary" />

            <com.google.android.material.floatingactionbutton.FloatingActionButton
                android:id="@+id/record"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:clickable="true"
                android:src="@drawable/ic_record"
                app:backgroundTint="?attr/colorPrimary"
                app:fabSize="auto"
                app:tint="#f2f2f2" />
        </LinearLayout>

    </androidx.coordinatorlayout.widget.CoordinatorLayout>

</androidx.constraintlayout.widget.ConstraintLayout>```

Answer 1

您需要使用addBottomSheetCallback来监听BottomSheet的滑动位置，通过这个值您可以顺利隐藏BottomNavigation:

private int navigationHeight;

bottomSheet.addBottomSheetCallback(new BottomSheetBehavior.BottomSheetCallback() {
            @Override
            public void onStateChanged(@NonNull View bottomSheet, int newState) {
              
            }

            @Override
            public void onSlide(@NonNull View bottomSheet, float slideOffset) {
               if (navigationHeight == 0)
                     navigationHeight = navigation.getHeight(); //the height of the navigationView
               float slideY = navigationHeight - navigationHeight * (1 - slideOffset);
               navigation.setTranslationY(slideY);//Translate the navigatinView
            }
        });

注意:为了获得良好的结果，您必须移动协调器布局上的底部导航