如何将BottomAppBar + FAB与BottomNavigationView结合

Question

我想使用FloatingActionButton以及锚定在BottomNavigationView顶部的BottomAppBar上时的行为。

我想出了一个相当“ hacky”的技巧，将其BottomNavigationView放置在BottomAppBar的顶部而不提供背景，从而使其透明。

乍一看，这似乎很好用，但是我发现只有在触摸按钮的上半部分时才能单击fab按钮（因此BottomNavigationView顶部没有透明的地方）。

<androidx.constraintlayout.widget.ConstraintLayout 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">

    <androidx.coordinatorlayout.widget.CoordinatorLayout
        android:layout_width="match_parent"
        android:layout_height="120dp"
        android:layout_gravity="bottom"
        app:layout_constraintBottom_toBottomOf="parent">

        <com.google.android.material.floatingactionbutton.FloatingActionButton
            android:id="@+id/fab"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:clickable="true"
            android:focusable="true"
            app:layout_anchor="@id/bar" />

        <com.google.android.material.bottomappbar.BottomAppBar
            android:id="@+id/bar"
            android:layout_width="match_parent"
            android:layout_height="58dp"
            android:layout_gravity="bottom"
            android:backgroundTint="@color/colorPrimaryDark" />

        <com.google.android.material.bottomnavigation.BottomNavigationView
            android:id="@+id/bottomNavigation"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_gravity="bottom"
            app:itemIconTint="@android:color/darker_gray"
            app:itemTextColor="@android:color/white"
            app:labelVisibilityMode="labeled"
            app:menu="@menu/navigation" />

    </androidx.coordinatorlayout.widget.CoordinatorLayout>
</androidx.constraintlayout.widget.ConstraintLayout>

有什么办法可以实现我完全可以点击的想法FloatingActionButton？

Answer 1

有一种更简单的方法来组合这 3 个小部件。我们可以有类似的东西：

<androidx.coordinatorlayout.widget.CoordinatorLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:id="@+id/coordinator"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <androidx.fragment.app.FragmentContainerView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_marginBottom="?attr/actionBarSize" />

    <com.google.android.material.bottomappbar.BottomAppBar
        android:id="@+id/bottomBar"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_gravity="bottom"
        app:backgroundTint="?attr/colorPrimary"
        app:contentInsetEnd="0dp"
        app:contentInsetStart="0dp"
        app:fabAlignmentMode="end">

        <com.google.android.material.bottomnavigation.BottomNavigationView
            android:id="@+id/bottomNavigation"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            app:backgroundTint="@android:color/transparent"
            app:elevation="0dp"
            android:layout_marginEnd="100dp"
            app:itemIconTint="@android:color/white"
            app:itemRippleColor="@android:color/white"
            app:itemTextColor="@android:color/white"
            app:menu="@menu/menu_activity_home_bottom_navigation" />

    </com.google.android.material.bottomappbar.BottomAppBar>

    <com.google.android.material.floatingactionbutton.FloatingActionButton
        android:id="@+id/fab"
        android:src="@drawable/ic_add_white_24dp"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        app:layout_anchor="@id/bottomBar" />


</androidx.coordinatorlayout.widget.CoordinatorLayout>

就是这样。

根据 FAB 的固定位置 (CENTER|END)，菜单图标将放置在左侧或中间：

对于此示例，结果将类似于：

如果您认为有更好的方法，请随时编辑/评论，以便我修复帖子:)

Answer 2

第一路

试试这个你可以创建一个 CustomBottomNavigationView

这是好文章 CustomBottomNavigationView

我如何在BottomNavigationView中绘制自定义形状

样本代码

import android.content.Context;
import android.graphics.*;
import android.support.design.widget.BottomNavigationView;
import android.support.v4.content.ContextCompat;
import android.util.AttributeSet;

public class CustomBottomNavigationView extends BottomNavigationView {

    private Path mPath;
    private Paint mPaint;

    /** the CURVE_CIRCLE_RADIUS represent the radius of the fab button */
    private final int CURVE_CIRCLE_RADIUS = 128 / 2;
    // the coordinates of the first curve
    private Point mFirstCurveStartPoint = new Point();
    private Point mFirstCurveEndPoint = new Point();
    private Point mFirstCurveControlPoint1 = new Point();
    private Point mFirstCurveControlPoint2 = new Point();

    //the coordinates of the second curve
    @SuppressWarnings("FieldCanBeLocal")
    private Point mSecondCurveStartPoint = new Point();
    private Point mSecondCurveEndPoint = new Point();
    private Point mSecondCurveControlPoint1 = new Point();
    private Point mSecondCurveControlPoint2 = new Point();
    private int mNavigationBarWidth;
    private int mNavigationBarHeight;

    public CustomBottomNavigationView(Context context) {
        super(context);
        init();
    }

    public CustomBottomNavigationView(Context context, AttributeSet attrs) {
        super(context, attrs);
        init();
    }

    public CustomBottomNavigationView(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        init();
    }

    private void init() {
        mPath = new Path();
        mPaint = new Paint();
        mPaint.setStyle(Paint.Style.FILL_AND_STROKE);
        mPaint.setColor(ContextCompat.getColor(getContext(),R.color.colorAccent));
        setBackgroundColor(Color.TRANSPARENT);
    }

    @Override
    protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
        super.onLayout(changed, left, top, right, bottom);

    }

    @Override
    protected void onSizeChanged(int w, int h, int oldw, int oldh) {
        super.onSizeChanged(w, h, oldw, oldh);
        // get width and height of navigation bar
        // Navigation bar bounds (width & height)
        mNavigationBarWidth = getWidth();
        mNavigationBarHeight = getHeight();
        // the coordinates (x,y) of the start point before curve
        mFirstCurveStartPoint.set((mNavigationBarWidth / 2) - (CURVE_CIRCLE_RADIUS * 2) - (CURVE_CIRCLE_RADIUS / 3), 0);
        // the coordinates (x,y) of the end point after curve
        mFirstCurveEndPoint.set(mNavigationBarWidth / 2, CURVE_CIRCLE_RADIUS + (CURVE_CIRCLE_RADIUS / 4));
        // same thing for the second curve
        mSecondCurveStartPoint = mFirstCurveEndPoint;
        mSecondCurveEndPoint.set((mNavigationBarWidth / 2) + (CURVE_CIRCLE_RADIUS * 2) + (CURVE_CIRCLE_RADIUS / 3), 0);

        // the coordinates (x,y)  of the 1st control point on a cubic curve
        mFirstCurveControlPoint1.set(mFirstCurveStartPoint.x + CURVE_CIRCLE_RADIUS + (CURVE_CIRCLE_RADIUS / 4), mFirstCurveStartPoint.y);
        // the coordinates (x,y)  of the 2nd control point on a cubic curve
        mFirstCurveControlPoint2.set(mFirstCurveEndPoint.x - (CURVE_CIRCLE_RADIUS * 2) + CURVE_CIRCLE_RADIUS, mFirstCurveEndPoint.y);

        mSecondCurveControlPoint1.set(mSecondCurveStartPoint.x + (CURVE_CIRCLE_RADIUS * 2) - CURVE_CIRCLE_RADIUS, mSecondCurveStartPoint.y);
        mSecondCurveControlPoint2.set(mSecondCurveEndPoint.x - (CURVE_CIRCLE_RADIUS + (CURVE_CIRCLE_RADIUS / 4)), mSecondCurveEndPoint.y);

        mPath.reset();
        mPath.moveTo(0, 0);
        mPath.lineTo(mFirstCurveStartPoint.x, mFirstCurveStartPoint.y);

        mPath.cubicTo(mFirstCurveControlPoint1.x, mFirstCurveControlPoint1.y,
                mFirstCurveControlPoint2.x, mFirstCurveControlPoint2.y,
                mFirstCurveEndPoint.x, mFirstCurveEndPoint.y);

        mPath.cubicTo(mSecondCurveControlPoint1.x, mSecondCurveControlPoint1.y,
                mSecondCurveControlPoint2.x, mSecondCurveControlPoint2.y,
                mSecondCurveEndPoint.x, mSecondCurveEndPoint.y);

        mPath.lineTo(mNavigationBarWidth, 0);
        mPath.lineTo(mNavigationBarWidth, mNavigationBarHeight);
        mPath.lineTo(0, mNavigationBarHeight);
        mPath.close();
    }

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        canvas.drawPath(mPath, mPaint);
    }
}

现在这样使用

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

    <android.support.design.widget.FloatingActionButton
        android:id="@+id/fab"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:layout_centerInParent="true"
        android:layout_marginBottom="30dp"
        android:clickable="true"
        android:focusable="true" />

    <neel.com.demo.CustomBottomNavigationView
        android:id="@+id/customBottomBar"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:background="@color/colorAccent"
        app:labelVisibilityMode="labeled" />


</RelativeLayout>

活动

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        CustomBottomNavigationView curvedBottomNavigationView = findViewById(R.id.customBottomBar);
        curvedBottomNavigationView.inflateMenu(R.menu.bottom_menu);
    }
}

输出值

第二路

    <androidx.coordinatorlayout.widget.CoordinatorLayout 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="120dp"
    android:layout_gravity="bottom">

    <com.google.android.material.floatingactionbutton.FloatingActionButton
        android:id="@+id/fab"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:clickable="true"
        android:focusable="true"
        app:layout_anchor="@id/bar" />

    <com.google.android.material.bottomappbar.BottomAppBar
        android:id="@+id/bar"
        android:layout_width="match_parent"
        android:layout_height="58dp"
        android:layout_gravity="bottom"
        android:backgroundTint="@color/colorPrimaryDark">

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:orientation="horizontal">

            <TextView
                style="?android:attr/borderlessButtonStyle"
                android:layout_width="0dp"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:background="?android:attr/selectableItemBackground"
                android:drawableTop="@drawable/ic_favorite"
                android:gravity="center"
                android:orientation="vertical"
                android:text="Personal"
                android:textColor="#FFFFFF">

            </TextView>

            <TextView
                style="?android:attr/borderlessButtonStyle"
                android:layout_width="0dp"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:background="?android:attr/selectableItemBackground"
                android:drawableTop="@drawable/ic_favorite"
                android:gravity="center"
                android:orientation="vertical"
                android:text="Personal"
                android:textColor="#FFFFFF">

            </TextView>

            <TextView
                style="?android:attr/borderlessButtonStyle"
                android:layout_width="0dp"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:background="?android:attr/selectableItemBackground"
                android:drawableTop="@drawable/ic_favorite"
                android:gravity="center"
                android:orientation="vertical"
                android:textColor="#FFFFFF"
                android:visibility="invisible">

            </TextView>

            <TextView
                style="?android:attr/borderlessButtonStyle"
                android:layout_width="0dp"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:background="?android:attr/selectableItemBackground"
                android:drawableTop="@drawable/ic_favorite"
                android:gravity="center"
                android:orientation="vertical"
                android:text="Personal"
                android:textColor="#FFFFFF">

            </TextView>

            <TextView
                style="?android:attr/borderlessButtonStyle"
                android:layout_width="0dp"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:background="?android:attr/selectableItemBackground"
                android:drawableTop="@drawable/ic_favorite"
                android:gravity="center"
                android:orientation="vertical"
                android:text="Personal"
                android:textColor="#FFFFFF">

            </TextView>

        </LinearLayout>

    </com.google.android.material.bottomappbar.BottomAppBar>

</androidx.coordinatorlayout.widget.CoordinatorLayout>

输出值

Answer 3

我找到了一个更快的解决方案。我将 bottomnavigationview 包裹在 frameLayout 中，一切都按预期工作。尝试这个：

    <?xml version="1.0" encoding="utf-8"?>
    <androidx.coordinatorlayout.widget.CoordinatorLayout 
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:id="@+id/lt_content"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@color/white"
    android:fitsSystemWindows="false">


    <ViewPager
        android:id="@+id/main_pager"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_above="@+id/bottom_navigation"
        android:layout_alignParentStart="true"
        app:layout_behavior="@string/appbar_scrolling_view_behavior" />

    <com.google.android.material.bottomappbar.BottomAppBar
        android:id="@+id/bottom_bar"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_gravity="bottom"
        android:clickable="false"
        app:fabAlignmentMode="center" />


    <FrameLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_gravity="bottom">

        <com.google.android.material.bottomnavigation.BottomNavigationView
            android:id="@+id/bottom_navigation"
            style="@style/BottomNavigationStyle"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:clickable="false"
            app:menu="@menu/bottom_menu" />


    </FrameLayout>


    <com.google.android.material.floatingactionbutton.FloatingActionButton
        android:id="@+id/fab"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        app:layout_anchor="@id/bottom_bar" />


</androidx.coordinatorlayout.widget.CoordinatorLayout>

Answer 4

对于所有使用Nilesh Rathod 评论中的第二种方法并希望在第一个文本视图之前删除意外空格的人：

刚刚设置app:contentInsetStart="0dp"为BottomAppBar