首页 > 解决方案 > 查看某个 Fragment 时隐藏 AppBarLayout

问题描述

我是 android 新手并尝试使用选项卡实现主要活动,每个选项卡都包含一个片段,并且在其中一个片段上我希望整个应用栏消失(它打算成为相机片段),留下某个片段在全屏模式下,这是我目前所拥有的:

文件:MainActivity.java

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
       //this.getWindow().addFlags(WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS);
        SectionsPagerAdapter sectionsPagerAdapter = new SectionsPagerAdapter(this, getSupportFragmentManager());
        ViewPager viewPager = findViewById(R.id.view_pager);
        viewPager.setAdapter(sectionsPagerAdapter);
        TabLayout tabs = findViewById(R.id.tabs);
        tabs.setupWithViewPager(viewPager);
        FloatingActionButton fab = findViewById(R.id.fab);


        final AppBarLayout bar = findViewById(R.id.appBarLayout2); // the app bar layout that i want gone

        tabs.addOnTabSelectedListener(new TabLayout.OnTabSelectedListener() {
            @Override
            public void onTabSelected(TabLayout.Tab tab)
            {
                
            }

            @Override
            public void onTabUnselected(TabLayout.Tab tab)
            {

            }

            @Override
            public void onTabReselected(TabLayout.Tab tab)
            {
                onTabSelected(tab);
            }
        });

如您所见,我正在尝试与 ViewPager 一起实现选项卡侦听器,我尝试在 bar.position() 上的 if 语句中实现:

文件:main_activity.xml

<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"
    tools:context=".UIActivity">

    <com.google.android.material.appbar.AppBarLayout
        android:id="@+id/appBarLayout2"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:theme="@style/AppTheme.AppBarOverlay"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="@+id/view_pager">

        <ImageView
            android:id="@+id/imageView1"
            android:layout_width="80dp"
            android:layout_height="50dp"
            android:layout_gravity="center"
            android:src="@mipmap/logo1" />

        <com.google.android.material.tabs.TabLayout
            android:id="@+id/tabs"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:background="?attr/colorPrimary"
            app:tabIndicatorColor="#ffffff"
            app:tabIndicatorHeight="2dp" /><!-- #86B2E8 -->
    </com.google.android.material.appbar.AppBarLayout>

    <androidx.viewpager.widget.ViewPager
        android:id="@+id/view_pager"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:layout_behavior="@string/appbar_scrolling_view_behavior"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <com.google.android.material.floatingactionbutton.FloatingActionButton
        android:id="@+id/fab"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginEnd="8dp"
        android:layout_marginRight="8dp"
        android:layout_marginBottom="16dp"
        app:layout_constraintBottom_toBottomOf="@+id/view_pager"
        app:layout_constraintEnd_toEndOf="parent"
        app:srcCompat="@android:drawable/ic_dialog_email" />
</androidx.constraintlayout.widget.ConstraintLayout>


cameraFragment.java 和 xml 文件是标准文件,我仍然不知道如何在用户单击相机选项卡时隐藏应用栏,并在他滑回另一个片段时将其返回。

标签: androidandroid-studioandroid-fragmentsandroid-designer

解决方案


操作栏属于活动,而不是您的片段。但是您可以创建一个没有操作栏的样式并更改片段开头的样式。

基于https://stackoverflow.com/a/15496425/8244139,您应该使用以下代码:

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {

    // create ContextThemeWrapper from the original Activity Context with the custom theme
    final Context contextThemeWrapper = new ContextThemeWrapper(getActivity(), R.style.yourCustomTheme);

    // clone the inflater using the ContextThemeWrapper
    LayoutInflater localInflater = inflater.cloneInContext(contextThemeWrapper);

    // inflate the layout using the cloned inflater, not default inflater
    return localInflater.inflate(R.layout.yourLayout, container, false);
}

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