android - 如何为 Android 实现 BottomAppBar？

Question

我正在尝试像 Android 文档中那样实现 BottomAppBar:

Android BottomAppBar

这是我能做到的最接近的结果:

我想要像 Android 一样在抽屉上有标题栏，并且能够滚动它并用顶角的 X 关闭它。

这是我目前的实现-

fragment_bottomsheet.xml:

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content">


    <com.google.android.material.navigation.NavigationView
        android:id="@+id/navigation_view"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_gravity="bottom"
        android:layout_marginStart="8dp"
        android:layout_marginTop="8dp"
        android:layout_marginEnd="8dp"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:menu="@menu/activity_main_drawer">
        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text=""/>
    </com.google.android.material.navigation.NavigationView>

</androidx.constraintlayout.widget.ConstraintLayout>

BottomNavigationDrawerFragment.java:

package com.jggdevelopment.wannacook.dialog_fragments;

import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

import com.google.android.material.bottomsheet.BottomSheetDialogFragment;
import com.jggdevelopment.wannacook.R;

import androidx.annotation.NonNull;
import androidx.annotation.Nullable;

public class BottomNavigationDrawerFragment extends BottomSheetDialogFragment {

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

和 MainActivity.java:

package com.jggdevelopment.wannacook;

import android.content.Intent;
import androidx.fragment.app.FragmentManager;
import android.os.Bundle;

import com.google.android.material.bottomappbar.BottomAppBar;
import com.google.android.material.navigation.NavigationView;
import androidx.appcompat.app.AppCompatActivity;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.WindowManager;

import com.google.android.material.floatingactionbutton.FloatingActionButton;

import com.google.firebase.auth.FirebaseAuth;
import com.google.firebase.database.DatabaseReference;
import com.google.firebase.database.FirebaseDatabase;
import com.jggdevelopment.wannacook.dialog_fragments.AddShoppingListItemDialog;
import com.jggdevelopment.wannacook.dialog_fragments.BottomNavigationDrawerFragment;
import com.jggdevelopment.wannacook.fragments.FridgeFragment;
import com.jggdevelopment.wannacook.fragments.ShoppingListFragment;
import com.jggdevelopment.wannacook.fragments.PantryFragment;
import com.jggdevelopment.wannacook.R;

/**
 * Main activity for the application, handles general housekeeping and side navigation
 */
public class MainActivity extends AppCompatActivity implements NavigationView.OnNavigationItemSelectedListener {

    private BottomAppBar bottomAppBar;
    private FloatingActionButton mFab;
    private FirebaseDatabase database = FirebaseDatabase.getInstance();
    private DatabaseReference db = database.getReference();

    private static final int RC_SIGN_IN = 123;

    /**
     * instantiates fields and sets the main screen to be the ShoppingListFragment
     * @param savedInstanceState
     */
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);
        setSupportActionBar(bottomAppBar);

        mFab = findViewById(R.id.fab);
        bottomAppBar = findViewById(R.id.bottom_app_bar);
        ShoppingListFragment shoppingListFragment = new ShoppingListFragment();

        getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_HIDDEN);
        getSupportFragmentManager().beginTransaction()
                .add(R.id.relative_layout_for_fragment, shoppingListFragment).commit();

        mFab.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                FragmentManager fm = getSupportFragmentManager();
                AddShoppingListItemDialog addItemDialogFragment = AddShoppingListItemDialog.newInstance("Title");
                addItemDialogFragment.show(fm, "new_shopping_list_item_dialog");
            }
        });

        bottomAppBar.setNavigationOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                BottomNavigationDrawerFragment bndf = new BottomNavigationDrawerFragment();
                bndf.show(getSupportFragmentManager(), bndf.getTag());
            }
        });
    }

    /**
     * handles functionality for the three dots option menu in the toolbar
     * @param menu menu to create
     * @return true
     */
    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.activity_main_drawer, menu);
        return true;
    }

    /**
     * handles what should happen when one of the options in the toolbar menu is selected
     * @param item
     * @return
     */
    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.

        if (item.getItemId() == R.id.action_sign_out) {
            FirebaseAuth.getInstance().signOut();
            Intent intent = new Intent(this, SignInActivity.class);
            intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
            startActivity(intent);
            return true;
        }

        return super.onOptionsItemSelected(item);
    }

    /**
     * handles what should happen when one of the options in the navigation menu is selected
     * @param item
     * @return
     */
    @Override
    public boolean onNavigationItemSelected(MenuItem item) {
        // Handle navigation view item clicks here.
        int id = item.getItemId();

        // home button
        if (id == R.id.nav_shopping_list) {
            ShoppingListFragment shoppingListFragment = new ShoppingListFragment();
            FragmentManager manager = getSupportFragmentManager();
            manager.beginTransaction().replace(
                    R.id.relative_layout_for_fragment,
                    shoppingListFragment,
                    shoppingListFragment.getTag()
            ).commit();
        }

        // fridge button
        else if (id == R.id.nav_fridge) {
            FridgeFragment fridgeFragment = new FridgeFragment();
            FragmentManager manager = getSupportFragmentManager();
            manager.beginTransaction().replace(
                    R.id.relative_layout_for_fragment,
                    fridgeFragment,
                    fridgeFragment.getTag()
            ).commit();
        }

        // pantry button
        else if (id == R.id.nav_pantry) {
            PantryFragment pantryFragment = new PantryFragment();
            FragmentManager manager = getSupportFragmentManager();
            manager.beginTransaction().replace(
                    R.id.relative_layout_for_fragment,
                    pantryFragment,
                    pantryFragment.getTag()
            ).commit();
        }

        // share button
        else if (id == R.id.nav_share) {
            // TODO: allow user to share app link with other people
        }

        // contact developer button
        else if (id == R.id.nav_contact) {
            // TODO: send intent to email application to email developer
        }

        return true;
    }


}

Answer 1

你实际上很接近。只需为 ButtomNavigationDrawerFragment 创建一个布局，如下所示:

<?xml version="1.0" encoding="utf-8"?>
<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/navigation_view_layout"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    app:behavior_hideable="true"
    app:layout_behavior="@string/bottom_sheet_behavior">

    <com.google.android.material.navigation.NavigationView
        android:id="@+id/navigation_view"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_gravity="bottom"
        android:layout_marginTop="4dp"
        android:paddingBottom="40dp"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.0"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/view2"
        app:menu="@menu/bottom_nav_drawer_menu"
        app:theme="@style/NavigationDrawerStyle" />

    <TextView
        android:id="@+id/textView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginStart="12dp"
        android:layout_marginTop="16dp"
        android:fontFamily="@font/rubik_medium"
        android:text="@string/bottom_sheet_name"
        android:textColor="@color/colorAccent"
        android:textSize="18sp"
        android:textStyle="bold"
        app:layout_constraintStart_toEndOf="@+id/imageView"
        app:layout_constraintTop_toTopOf="parent" />

    <TextView
        android:id="@+id/textView2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="2dp"
        android:text="@string/bottom_sheet_email"
        android:textColor="@color/colorAccent"
        app:layout_constraintStart_toStartOf="@+id/textView"
        app:layout_constraintTop_toBottomOf="@+id/textView" />

    <ImageView
        android:id="@+id/imageView"
        android:layout_width="48dp"
        android:layout_height="48dp"
        android:layout_marginStart="24dp"
        android:background="@drawable/baseline_account_circle_black_48"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="@+id/textView" />

    <View
        android:id="@+id/view2"
        android:layout_width="match_parent"
        android:layout_height="2dip"
        android:layout_marginTop="15dp"
        android:background="#447e7e7e"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.0"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/textView2" />

    <ImageView
        android:id="@+id/close_imageview"
        android:layout_width="24dp"
        android:layout_height="24dp"
        android:layout_marginTop="8dp"
        android:layout_marginEnd="16dp"
        android:layout_marginBottom="8dp"
        android:background="@drawable/baseline_close_black_24"
        android:visibility="gone"
        app:layout_constraintBottom_toBottomOf="@+id/textView2"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintTop_toTopOf="@+id/textView" />

</androidx.constraintlayout.widget.ConstraintLayout>

然后在 onCreateDialog() 中使用 setBottomSheetCallback() 和 onStateChanged() 来膨胀布局并实现预期的行为:( Kotlin )

class BottomNavigationDrawerFragment: BottomSheetDialogFragment() {

    override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
        return inflater.inflate(R.layout.fragment_bottom_navigation_drawer, container, false)
    }

    override fun onActivityCreated(savedInstanceState: Bundle?) {
        super.onActivityCreated(savedInstanceState)

        navigation_view.setNavigationItemSelectedListener { menuItem ->
            // Bottom Navigation Drawer menu item clicks
            when (menuItem.itemId) {
//                R.id.nav1 -> context!!.toast(getString(R.string.nav1_clicked))
            }
            // Add code here to update the UI based on the item selected
            // For example, swap UI fragments here
            true
        }

        close_imageview.setOnClickListener {
            this.dismiss()
        }

        disableNavigationViewScrollbars(navigation_view)

    }

    override fun onCreateDialog(savedInstanceState: Bundle?): Dialog {
        val dialog = super.onCreateDialog(savedInstanceState) as BottomSheetDialog

        dialog.setOnShowListener { dialog ->
            val d = dialog as BottomSheetDialog

            val bottomSheet = d.findViewById<View>(R.id.design_bottom_sheet) as FrameLayout?
            val bottomSheetBehavior = BottomSheetBehavior.from(bottomSheet!!)
            bottomSheetBehavior.setBottomSheetCallback(object: BottomSheetBehavior.BottomSheetCallback() {
                override fun onSlide(bottomSheet: View, slideOffset: Float) {
                    if (slideOffset > 0.5) {
                        close_imageview.visibility = View.VISIBLE
                    } else {
                        close_imageview.visibility = View.GONE
                    }
                }

                override fun onStateChanged(bottomSheet: View, newState: Int) {
                    when (newState) {
                        BottomSheetBehavior.STATE_HIDDEN-> dismiss()
//                        else -> close_imageview.visibility = View.GONE
                    }
                }
            })
        }

        return dialog
    }

    private fun disableNavigationViewScrollbars(navigationView: NavigationView?) {
        val navigationMenuView = navigationView?.getChildAt(0) as NavigationMenuView
        navigationMenuView.isVerticalScrollBarEnabled = false
    }


}

您正在寻找的确切行为可用in this GitHub repo . (和 the medium link )

结果将是: