在ReyclerView中滚动时隐藏Actionbar〔Android Studio〕

Question

如何在Android中滚动RecyclerView时隐藏操作栏。这是我正在使用的代码：

<?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"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.example.myapp.activities.Profile_Page">
<androidx.constraintlayout.widget.ConstraintLayout
android:layout_width="match_parent"
android:layout_height="87dp"
android:background="@color/colorPrimary"
app:layout_constraintBottom_toTopOf="@+id/notifications_view"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.0"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="left|center_vertical"
android:fontFamily="@font/roboto_medium"
android:text="Notifications"
android:textAlignment="center"
android:textColor="#FFFFFF"
android:textSize="27sp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"></TextView>
</androidx.constraintlayout.widget.ConstraintLayout>
<androidx.recyclerview.widget.RecyclerView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_marginTop="87dp"
android:padding="10dp"
android:id="@+id/notifications_view"
app:layout_behavior="@string/appbar_scrolling_view_behavior"
></androidx.recyclerview.widget.RecyclerView>
</androidx.coordinatorlayout.widget.CoordinatorLayout>

为了初始化ActionBar，我在Java文件中添加了以下代码：

getSupportActionBar().setDisplayHomeAsUpEnabled(true);
getSupportActionBar().setDisplayShowTitleEnabled(false);
getSupportActionBar().setElevation(0);

滚动页面时，有哪些方法可以隐藏操作栏？我已经使用Constraint布局以自定义的方式显示活动的标题，并使其看起来很好看。

当用户滚动时，操作栏和ConstraintLayout都应该隐藏。

Answer 1

您需要将约束布局包装在AppBarLayout中，并将layout_scrollFlags添加到约束布局中，如下所示：

<com.google.android.material.appbar.AppBarLayout
android:id="@+id/appbar_layout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:elevation="0dp"
>
<androidx.constraintlayout.widget.ConstraintLayout
android:layout_width="match_parent"
android:layout_height="87dp"
android:background="@color/colorPrimary"
app:layout_constraintBottom_toTopOf="@+id/notifications_view"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.0"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_scrollFlags="scroll|enterAlways|snap"
>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="left|center_vertical"
android:fontFamily="@font/roboto_medium"
android:text="Notifications"
android:textAlignment="center"
android:textColor="#FFFFFF"
android:textSize="27sp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"></TextView>
</androidx.constraintlayout.widget.ConstraintLayout>
</com.google.android.material.appbar.AppBarLayout>

Answer 2

您需要使用CollapsingToolbarLayout和NestedScrollView。我有一部分代码。在那里我写了一个没有完全崩溃的动作栏。

<?xml version="1.0" encoding="utf-8"?>
<FrameLayout 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">
<androidx.coordinatorlayout.widget.CoordinatorLayout
android:id="@+id/cityBlock"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@color/sky_blue"
android:visibility="gone"
tools:visibility="visible">

<com.google.android.material.appbar.AppBarLayout
android:id="@+id/cityAppBar"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="@color/colorPrimaryDark">
<com.google.android.material.appbar.CollapsingToolbarLayout
android:id="@+id/cityToolbar"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:collapsedTitleGravity="start"
app:collapsedTitleTextAppearance="@style/CollapsedAppBar"
app:contentScrim="@color/sky_blue"
app:expandedTitleGravity="center|top"
app:expandedTitleTextAppearance="@style/ExpandedAppBar"
app:layout_scrollFlags="scroll|exitUntilCollapsed|snap"
app:titleEnabled="true">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal|bottom"
android:layout_marginTop="@dimen/huge_margin"
android:layout_marginBottom="@dimen/default_margin"
android:gravity="center"
android:orientation="vertical"
app:layout_collapseMode="parallax"
app:layout_collapseParallaxMultiplier="0.5">
<TextView
android:id="@+id/countryTitle"
style="@style/TextAppearance.MaterialComponents.Subtitle1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textColor="@android:color/white"
tools:text="Russia" />
<TextView
android:id="@+id/weatherDate"
style="@style/TextAppearance.MaterialComponents.Subtitle1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textColor="@android:color/white"
tools:text="20.20.20" />
<ImageView
android:id="@+id/weatherBigImage"
android:layout_width="56dp"
android:layout_height="56dp"
android:layout_margin="@dimen/mini_margin"
tools:src="@drawable/ic_test_icon_2" />
<TextView
android:id="@+id/mainTemp"
style="@style/TemperatureTitle"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
tools:text="10u00B0" />
<TextView
android:id="@+id/minMaxTempFull"
style="@style/MinMaxTemperatureTitle"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_margin="@dimen/default_margin"
tools:text="@string/min_max_temp_pattern" />
</LinearLayout>
<androidx.appcompat.widget.Toolbar
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
app:layout_collapseMode="pin"
app:layout_scrollFlags="scroll|exitUntilCollapsed|snap" />
</com.google.android.material.appbar.CollapsingToolbarLayout>
</com.google.android.material.appbar.AppBarLayout>
<androidx.swiperefreshlayout.widget.SwipeRefreshLayout
android:id="@+id/cityDetailSwipeRefreshLayout"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="com.google.android.material.appbar.AppBarLayout$ScrollingViewBehavior"
app:layout_scrollFlags="scroll|enterAlways">
<androidx.core.widget.NestedScrollView
android:layout_width="match_parent"
android:layout_height="wrap_content">
<androidx.constraintlayout.widget.ConstraintLayout
android:layout_width="match_parent"
android:layout_height="wrap_content">
<androidx.cardview.widget.CardView
android:id="@+id/detailBlock"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="5dp"
app:cardCornerRadius="15dp"
app:cardElevation="5dp"
app:cardUseCompatPadding="true"
app:contentPaddingBottom="@dimen/default_margin"
app:contentPaddingTop="@dimen/default_margin"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent">
<androidx.constraintlayout.widget.ConstraintLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="@dimen/default_margin">
<FrameLayout
android:id="@+id/humidityBlock"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginBottom="@dimen/default_margin"
app:layout_constraintBottom_toTopOf="@id/humidityTitle"
app:layout_constraintEnd_toStartOf="@id/windBlock"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintWidth_percent="30">
<ImageView
android:id="@+id/humidityImage"
android:layout_width="36dp"
android:layout_height="36dp"
android:layout_gravity="center"
android:layout_marginEnd="@dimen/mini_margin"
android:src="@drawable/ic_humidity" />
</FrameLayout>
<FrameLayout
android:id="@+id/windBlock"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginBottom="@dimen/default_margin"
app:layout_constraintBottom_toTopOf="@id/windSpeedTitle"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toEndOf="@id/humidityBlock"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintWidth_percent="70">
<ImageView
android:id="@+id/windImage"
android:layout_width="36dp"
android:layout_height="36dp"
android:layout_gravity="center"
android:layout_marginEnd="@dimen/mini_margin"
android:src="@drawable/ic_wind" />
</FrameLayout>
<TextView
android:id="@+id/humidityTitle"
style="@style/ValuesHint"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginEnd="@dimen/mini_margin"
android:text="@string/humidity_hint"
app:layout_constraintBottom_toTopOf="@id/humidityValue"
app:layout_constraintEnd_toStartOf="@id/windSpeedTitle"
app:layout_constraintStart_toStartOf="@id/humidityBlock"
app:layout_constraintTop_toBottomOf="@id/humidityBlock" />
<TextView
android:id="@+id/humidityValue"
style="@style/ValuesHint"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="@dimen/mini_margin"
android:text="@string/percentage_pattern"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintStart_toStartOf="@id/humidityTitle"
app:layout_constraintTop_toBottomOf="@id/humidityTitle" />
<View
android:id="@+id/mainDivider"
android:layout_width="1dp"
android:layout_height="0dp"
android:background="@color/light_gray"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toStartOf="@id/windSpeedTitle"
app:layout_constraintStart_toEndOf="@id/humidityTitle"
app:layout_constraintTop_toTopOf="parent" />
<TextView
android:id="@+id/windSpeedTitle"
style="@style/ValuesHint"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginEnd="@dimen/mini_margin"
android:text="@string/wind_speed_title"
android:textColor="@android:color/holo_blue_dark"
app:layout_constraintBottom_toTopOf="@id/windSpeedValue"
app:layout_constraintEnd_toStartOf="@id/divider2"
app:layout_constraintStart_toStartOf="@id/windBlock"
app:layout_constraintTop_toBottomOf="@id/windBlock" />
<TextView
android:id="@+id/windSpeedValue"
style="@style/ValuesHint"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_alignParentEnd="true"
android:layout_marginTop="@dimen/mini_margin"
android:textColor="@android:color/holo_blue_dark"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintStart_toStartOf="@id/windSpeedTitle"
app:layout_constraintTop_toBottomOf="@id/windSpeedTitle"
tools:text="@string/wind_speed_pattern" />
<View
android:id="@+id/divider2"
android:layout_width="1dp"
android:layout_height="0dp"
android:layout_marginTop="@dimen/mini_margin"
android:layout_marginEnd="@dimen/mini_margin"
android:background="@color/light_gray"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toStartOf="@id/windDirectionTitle"
app:layout_constraintStart_toEndOf="@id/windSpeedTitle"
app:layout_constraintTop_toBottomOf="@id/humidityBlock" />
<TextView
android:id="@+id/windDirectionTitle"
style="@style/ValuesHint"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginEnd="@dimen/mini_margin"
android:text="@string/wind_direction_title"
android:textColor="@android:color/holo_blue_dark"
app:layout_constraintBottom_toTopOf="@id/windDirectionValue"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toEndOf="@id/divider2"
app:layout_constraintTop_toTopOf="@id/windSpeedTitle" />
<TextView
android:id="@+id/windDirectionValue"
style="@style/ValuesHint"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="@dimen/mini_margin"
android:textColor="@android:color/holo_blue_dark"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintStart_toStartOf="@id/windDirectionTitle"
app:layout_constraintTop_toBottomOf="@id/windDirectionTitle"
tools:text="NorthEast" />
</androidx.constraintlayout.widget.ConstraintLayout>
</androidx.cardview.widget.CardView>
<TextView
android:id="@+id/hourlyTitle"
style="@style/FragmentsTitle"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_margin="@dimen/default_margin"
android:text="@string/hourly_title"
app:layout_constraintBottom_toTopOf="@id/hourlyFragment"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@id/detailBlock" />
<fragment
android:id="@+id/hourlyFragment"
android:name="com.pesiik.goodbadweather.ui.forecast.ForecastFragment"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginTop="@dimen/default_margin"
android:tag="@string/hourly_fragment_tag"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@id/hourlyTitle" />
<TextView
android:id="@+id/dailyTitle"
style="@style/FragmentsTitle"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_margin="@dimen/default_margin"
android:text="@string/daily_title"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@id/hourlyFragment" />
<fragment
android:id="@+id/dailyFragment"
android:name="com.pesiik.goodbadweather.ui.forecast.ForecastFragment"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginTop="@dimen/default_margin"
android:layout_marginBottom="32dp"
android:tag="@string/daily_fragment_tag"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@id/dailyTitle" />
</androidx.constraintlayout.widget.ConstraintLayout>
</androidx.core.widget.NestedScrollView>
</androidx.swiperefreshlayout.widget.SwipeRefreshLayout>
</androidx.coordinatorlayout.widget.CoordinatorLayout>
<androidx.swiperefreshlayout.widget.SwipeRefreshLayout
android:id="@+id/emptyCityBlockResfreshLayout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:visibility="gone">
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:id="@+id/emptyCityTitle"
style="@style/CityTitle"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:layout_margin="@dimen/default_margin"
android:layout_marginTop="100dp"
android:text="@string/empty_city" />
<ImageView
android:layout_width="56dp"
android:layout_height="150dp"
android:layout_below="@id/emptyCityTitle"
android:layout_centerHorizontal="true"
android:src="@drawable/ic_arrow_pointing_down" />
</RelativeLayout>
</androidx.swiperefreshlayout.widget.SwipeRefreshLayout>
</FrameLayout>