Question

我想隐藏底部导航栏，所以我使用底部导航行为它有效，当我有其他代码，但在这似乎不起作用我尝试但底部导航栏不会隐藏这是代码

 package com.blipclap.creativegraphy.Helper;
import android.content.Context;
import android.support.annotation.NonNull;
import android.support.design.widget.CoordinatorLayout;
import android.support.design.widget.Snackbar;
import android.support.v4.view.ViewCompat;
import android.util.AttributeSet;
import android.view.Gravity;
import android.view.View;

import static java.lang.Float.parseFloat;

public class BottomNavigationBehaviour extends CoordinatorLayout.Behavior {

    public BottomNavigationBehaviour() {
    }

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

    @Override
    public boolean onStartNestedScroll(@NonNull CoordinatorLayout coordinatorLayout, @NonNull View child, @NonNull View directTargetChild, @NonNull View target, int axes, int type) {
        return axes== ViewCompat.SCROLL_AXIS_VERTICAL;
    }

    @Override
    public void onNestedScroll(@NonNull CoordinatorLayout coordinatorLayout, @NonNull View child, @NonNull View target, int dxConsumed, int dyConsumed, int dxUnconsumed, int dyUnconsumed, int type) {
        super.onNestedScroll(coordinatorLayout, child, target, dxConsumed, dyConsumed, dxUnconsumed, dyUnconsumed, type);
        child.setTranslationY(Math.max(0f,
                Math.min(Float.parseFloat(String.valueOf(child.getHeight())),child.getTranslationY()+dyConsumed)));
    }

    @Override
    public boolean layoutDependsOn(CoordinatorLayout parent, View child, View dependency) {
        if (dependency instanceof Snackbar.SnackbarLayout)
            updateSnackbar(child,dependency);
        return super.layoutDependsOn(parent, child, dependency);
    }

    private void updateSnackbar(View child, View dependency) {
        if (dependency.getLayoutParams()instanceof CoordinatorLayout.LayoutParams) {
            CoordinatorLayout.LayoutParams params = (CoordinatorLayout.LayoutParams) dependency.getLayoutParams();

            params.setAnchorId(child.getId());
            params.anchorGravity= Gravity.TOP;
            params.gravity=Gravity.TOP;
            dependency.setLayoutParams(params);

        }
    }
}

这是我的布局内容布局我尝试更改相对布局但不幸的是app停止了所以我无法改变它

<android.support.design.widget.CoordinatorLayout 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:layout_width="match_parent"
    android:layout_height="match_parent"
    app:layout_behavior="@string/appbar_scrolling_view_behavior"
    tools:context="com.blipclap.creativegraphy.HomeActivity"
    tools:showIn="@layout/app_bar_home">

    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="@android:color/white">

        <android.support.design.widget.TabLayout
            android:id="@+id/tabLayout"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"></android.support.design.widget.TabLayout>

        <android.support.v4.view.ViewPager
            android:id="@+id/viewPager"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            app:layoutManager="android.support.v7.widget.LinearLayoutManager"
            app:layout_behavior="@string/appbar_scrolling_view_behavior"
            android:layout_above="@+id/navigation"
            android:layout_below="@+id/tabLayout"></android.support.v4.view.ViewPager>

        <android.support.design.widget.BottomNavigationView
            android:id="@+id/navigation"
            android:layout_gravity="bottom"
            app:layout_behavior=".Helper.BottomNavigationBehavior"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_alignParentBottom="true"
            android:background="@color/colorPrimary"
            app:itemIconTint="@android:color/background_dark"
            app:itemTextColor="@android:color/background_dark"
            app:menu="@menu/bottom_navigation_menu"></android.support.design.widget.BottomNavigationView>
    </RelativeLayout>

</android.support.design.widget.CoordinatorLayout>

这是我正在使用的3个片段，当我滚动底部导航栏不隐藏分类

 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    tools:context="com.blipclap.creativegraphy.Fragment.CategoryFragment">

    <android.support.v7.widget.RecyclerView
        android:id="@+id/recycler_category"
        app:layoutManager="android.support.v7.widget.LinearLayoutManager"
        app:layout_behavior="@string/appbar_scrolling_view_behavior"
        android:layout_width="match_parent"
        android:layout_height="match_parent"></android.support.v7.widget.RecyclerView>

</RelativeLayout>

每日流行

 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    tools:context="com.blipclap.creativegraphy.Fragment.CategoryFragment">

    <android.support.v7.widget.RecyclerView
        android:id="@+id/recycler_trending"
        app:layoutManager="android.support.v7.widget.LinearLayoutManager"
        app:layout_behavior="@string/appbar_scrolling_view_behavior"
        android:layout_width="match_parent"
        android:layout_height="match_parent"></android.support.v7.widget.RecyclerView>

</RelativeLayout>

最近

    <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    tools:context="com.blipclap.creativegraphy.Fragment.CategoryFragment">

    <android.support.v7.widget.RecyclerView
        android:id="@+id/recycler_recent"
        app:layoutManager="android.support.v7.widget.LinearLayoutManager"
        app:layout_behavior="@string/appbar_scrolling_view_behavior"
        android:layout_width="match_parent"
        android:layout_height="match_parent"></android.support.v7.widget.RecyclerView>

</RelativeLayout>

此代码对我不起作用我应该做什么解决方案

refrence

bottom navigation behavior reference 1

bottom navigation behavior reference 2

bottom navigation behavior reference 3

我跟着最后一个，但它不起作用

Answer 1

有两件事：

1）您不应该覆盖onNestedScroll，它应该是onNestedPreScroll，删除onNestedScroll并将其替换为：

@Override
public void onNestedPreScroll(@NonNull CoordinatorLayout coordinatorLayout, @NonNull View child, @NonNull View target, int dx, int dy, @NonNull int[] consumed, int type) {
    super.onNestedPreScroll(coordinatorLayout, child, target, dx, dy, consumed, type);
    child.setTranslationY(Math.max(0f,
            Math.min(Float.parseFloat(String.valueOf(child.getHeight())),child.getTranslationY()+dy)));
}

2）在您的XML文件中，您输入

app:layout_behavior=".Helper.BottomNavigationBehavior"

您的班级名称是

BottomNavigationBehaviour

你可以看到一个是Behavi 我们的，另一个是Behav ior ，通常它会抛出运行时错误，应用程序应该无法运行，这可能是你的错字，但我提到它以防万一。

但请注意，此代码有错误，如果您尝试向下或向上滚动，RecyclerView项目将无法点击几秒钟，我有一个similar bug 。目前，我的选择是使用动画隐藏BottomNavigationView，如this帖子中所述。

修改

由于BottomNavigationView不是CoordinatorLayout的直接子项，因此可能未应用此行为，因此您可以完全删除RelativeLayout或删除BottomNavigationView ：

<android.support.design.widget.CoordinatorLayout 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:layout_width="match_parent" android:layout_height="match_parent" app:layout_behavior="@string/appbar_scrolling_view_behavior" tools:context="com.blipclap.creativegraphy.HomeActivity" tools:showIn="@layout/app_bar_home"> <RelativeLayout android:layout_width="match_parent" android:layout_height="wrap_content" android:background="@android:color/white"> <android.support.design.widget.TabLayout android:id="@+id/tabLayout" android:layout_width="match_parent" android:layout_height="wrap_content"></android.support.design.widget.TabLayout> <android.support.v4.view.ViewPager android:id="@+id/viewPager" android:layout_width="match_parent" android:layout_height="match_parent" app:layoutManager="android.support.v7.widget.LinearLayoutManager" app:layout_behavior="@string/appbar_scrolling_view_behavior" android:layout_above="@+id/navigation" android:layout_below="@+id/tabLayout"></android.support.v4.view.ViewPager> </RelativeLayout> <android.support.design.widget.BottomNavigationView android:id="@+id/navigation" android:layout_gravity="bottom" app:layout_behavior=".Helper.BottomNavigationBehavior" android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_alignParentBottom="true" android:background="@color/colorPrimary" app:itemIconTint="@android:color/background_dark" app:itemTextColor="@android:color/background_dark" app:menu="@menu/bottom_navigation_menu"> </android.support.design.widget.BottomNavigationView> </android.support.design.widget.CoordinatorLayout>

Answer 2

BottomLayoutBehavior.java

package com.utility.behaviour;

import android.content.Context;
import android.util.AttributeSet;
import android.view.View;

import androidx.annotation.NonNull;
import androidx.coordinatorlayout.widget.CoordinatorLayout;
import androidx.core.view.ViewCompat;

public class BottomLayoutBehavior<V extends View> extends CoordinatorLayout.Behavior<V> {

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

    @Override
    public boolean onStartNestedScroll(@NonNull CoordinatorLayout coordinatorLayout, @NonNull V child,
                                       @NonNull View directTargetChild, @NonNull View target, int axes, int type) {
        return axes == ViewCompat.SCROLL_AXIS_VERTICAL;
    }

    @Override
    public void onNestedPreScroll(@NonNull CoordinatorLayout coordinatorLayout, @NonNull V child,
                                  @NonNull View target, int dx, int dy, @NonNull int[] consumed, int type) {
        child.setTranslationY(Math.max(0f, Math.min(child.getHeight(), child.getTranslationY() + dy)));
        super.onNestedPreScroll(coordinatorLayout, child, target, dx, dy, consumed, type);
    }
}

activity_main.xml

<androidx.coordinatorlayout.widget.CoordinatorLayout
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <com.google.android.material.appbar.AppBarLayout
        android:id="@+id/appbar"
        android:layout_width="match_parent"
        android:layout_height="wrap_content">

        <include layout="@layout/app_bar" />
    </com.google.android.material.appbar.AppBarLayout>

    <com.utility.viewpager.SwipeOnOffViewPager
        android:id="@+id/viewpager"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:layout_behavior="@string/appbar_scrolling_view_behavior" />

    <com.google.android.material.bottomnavigation.BottomNavigationView
        android:id="@+id/bnvHome"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_gravity="bottom"
        android:background="@color/white"
        app:itemIconTint="@color/home_tab_bg"
        app:itemTextColor="@color/home_tab_bg"
        app:labelVisibilityMode="labeled"
        app:layout_anchorGravity="center"
        app:layout_behavior="com.utility.behaviour.BottomLayoutBehavior"
        app:menu="@menu/home_bottom_navigation_items" />
    <!--app:itemBackground="@drawable/home_bottom_bar_gap"-->
</androidx.coordinatorlayout.widget.CoordinatorLayout>

注意：android:layout_gravity="bottom"和app:layout_behavior="com.utility.behaviour.BottomLayoutBehavior"是必填项。

当滚动底部导航栏不隐藏时 - BottomNavigationBehavior

2 个答案: