java - 无法正确隐藏底部导航栏

问题描述

我已经从 android studio 模板创建了一个抽屉活动，并且我确实激活了 che 全粘性沉浸式模式，因此我并不总是看到标题栏和底部导航栏，但事实是该栏仍然占据屏幕上的空间并让我无法将物品放在上面（与酒吧重叠）。我希望该栏根本不存在，只有在某人在屏幕上向上或向下滑动时才显示，并且在显示时与屏幕底部的任何项目位置重叠。看看这个例子：

应该如何

怎么样

另外，我将此代码放在 MainActivity 中以使用粘性完全沉浸模式

    @Override
    public void onWindowFocusChanged(boolean hasFocus) {
        super.onWindowFocusChanged(hasFocus);
        if (hasFocus) {
            hideSystemUI();
        }
    }

    private void hideSystemUI() {
        // Enables regular immersive mode.
        // For "lean back" mode, remove SYSTEM_UI_FLAG_IMMERSIVE.
        // Or for "sticky immersive," replace it with SYSTEM_UI_FLAG_IMMERSIVE_STICKY
        View decorView = getWindow().getDecorView();
        decorView.setSystemUiVisibility(
                View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY
                        | View.SYSTEM_UI_FLAG_LAYOUT_STABLE // Set the content to appear under the system bars so that the
                        | View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION// content doesn't resize when the system bars hide and show.
                        | View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
                        // Hide the nav bar and status bar
                        | View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
                        | View.SYSTEM_UI_FLAG_FULLSCREEN);
    }

    // Shows the system bars by removing all the flags
// except for the ones that make the content appear under the system bars.
    private void showSystemUI() {
        View decorView = getWindow().getDecorView();
        decorView.setSystemUiVisibility(
                View.SYSTEM_UI_FLAG_LAYOUT_STABLE
                        | View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
                        | View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN);
    }

这是清单

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.prova3">

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@android:style/Theme.NoTitleBar.Fullscreen">
        <activity
            android:name=".MainActivity"
            android:label="@string/app_name"
            android:theme="@style/AppTheme.NoActionBar">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

这是我发布的特定片段的 xml：

<?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:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@drawable/background"
    tools:context=".ui.login.LoginFragment">


    <TextView
        android:id="@+id/textView2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="104dp"
        android:text="Bentornato"
        android:textColor="@android:color/black"
        android:textSize="20sp"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <EditText
        android:id="@+id/editText2"
        android:layout_width="325dp"
        android:layout_height="46dp"
        android:layout_marginTop="148dp"
        android:ems="10"
        android:inputType="textPersonName"
        android:hint="Email"
        android:textColorHint="@android:color/white"
        android:textColor="@android:color/white"
        android:backgroundTint="@android:color/white"
        app:layout_constraintEnd_toEndOf="parent"
        android:drawableRight="@drawable/ic_user"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/textView2" />

    <EditText
        android:id="@+id/editText3"
        android:layout_width="322dp"
        android:layout_height="46dp"
        android:layout_marginTop="16dp"
        android:ems="10"
        android:hint="Password"
        android:inputType="textPassword"
        android:textColor="@android:color/white"
        android:backgroundTint="@android:color/white"
        android:textColorHint="@android:color/white"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.483"
        app:layout_constraintStart_toStartOf="parent"
        android:drawableRight="@drawable/ic_key"
        app:layout_constraintTop_toBottomOf="@+id/editText2" />

    <Button
        android:id="@+id/button"
        android:layout_width="114dp"
        android:layout_height="33dp"
        android:layout_marginTop="76dp"
        android:background="@drawable/button_bg"
        android:backgroundTint="#7AFFFFFF"
        android:text="Login"
        android:textColor="@android:color/white"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.498"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/editText3" />

    <ImageButton
        android:id="@+id/backButton"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginStart="16dp"
        android:layout_marginTop="16dp"
        android:backgroundTint="#00FFFFFF"
        android:src="@drawable/ic_back_arrow"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

</androidx.constraintlayout.widget.ConstraintLayout>

这是托管片段的主要活动之一：

<?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:layout_width="match_parent"
    android:layout_height="match_parent"
    app:layout_behavior="@string/appbar_scrolling_view_behavior"
    tools:showIn="@layout/app_bar_main">

    <fragment
        android:id="@+id/nav_host_fragment"
        android:name="androidx.navigation.fragment.NavHostFragment"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:defaultNavHost="true"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:navGraph="@navigation/mobile_navigation" />
</androidx.constraintlayout.widget.ConstraintLayout>

标签： javaandroidandroid-layoutnavigationandroid-bottomnav

java - 无法正确隐藏底部导航栏

问题描述

解决方案

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