当特定片段处于活动状态时，试图从工具栏菜单中隐藏某些项目时出现问题。 （编辑：在这种情况下，工具栏未设置为ActionBar）
我一直在寻找解决方案，发现可以设置MenuItem的可见性，我尝试实现此功能，但是却收到一条错误消息，指出MenuItem实际上是一个ActionMenuItemView。
我不知道这是否与我使用Androidx有关。之后，我尝试用ActionMenuItemView替换MenuItem来查找是否存在一种可以隐藏视图但找不到任何视图的方法。
这是我的代码（在这种情况下，当备份片段处于活动状态时，我想在工具栏上隐藏刷新图标）：
public class HomeActivity extends AppCompatActivity {
private Toolbar toolbar2;
final Fragment fragment1 = new HomeFragment();
final Fragment fragment2 = new ReportFragment();
final Fragment fragment3 = new BackupFragment();
final Fragment fragment4 = new SettingFragment();
final FragmentManager fm = getSupportFragmentManager();
Fragment active = fragment1;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_home);
//Setting up the Toolbar
toolbar2 = (Toolbar)findViewById(R.id.toolbar_2);
toolbar2.inflateMenu(R.menu.test_menu);
//Setting bottom navaigation view
BottomNavigationView navigation = findViewById(R.id.navigation);
navigation.setOnNavigationItemSelectedListener(mOnNavigationItemSelectedListener);
fm.beginTransaction().add(R.id.main_container, fragment4, "4").hide(fragment4).commit();
fm.beginTransaction().add(R.id.main_container, fragment3, "3").hide(fragment3).commit();
fm.beginTransaction().add(R.id.main_container, fragment2, "2").hide(fragment2).commit();
fm.beginTransaction().add(R.id.main_container,fragment1, "1").commit();
}
private BottomNavigationView.OnNavigationItemSelectedListener mOnNavigationItemSelectedListener
= item -> {
switch (item.getItemId()) {
case R.id.navigation_home:
fm.beginTransaction().hide(active).show(fragment1).commit();
active = fragment1;
toolbar2.setTitle("Submitted Reports");
return true;
case R.id.navigation_report:
fm.beginTransaction().hide(active).show(fragment2).commit();
active = fragment2;
toolbar2.setTitle("Templates Reports");
return true;
case R.id.navigation_backup:
fm.beginTransaction().hide(active).show(fragment3).commit();
active = fragment3;
toolbar2.setTitle("Upload Reports");
MenuItem refresh = (MenuItem)findViewById(R.id.action_refresh);
refresh.setVisible(false);
return true;
case R.id.navigation_setting:
fm.beginTransaction().hide(active).show(fragment4).commit();
active = fragment4;
toolbar2.setTitle("Settings");
return true;
}
return false;
};
布局：
<?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:id="@+id/container"
tools:context="com.shid.form.UI.HomeActivity"
android:fitsSystemWindows="true"
android:background="@color/primary">
<androidx.appcompat.widget.Toolbar
android:id="@+id/toolbar_2"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="@color/colorPrimary"
android:elevation="6dp"
android:minHeight="?attr/actionBarSize"
app:navigationIcon="@drawable/ic_menu"
app:popupTheme="@style/Theme.Popup"
app:theme="@style/Theme.GuidelinesCompat.Toolbar"
app:title="Submitted Reports" />
<!-- Fragments Container -->
<FrameLayout
android:id="@+id/fragment_container"
android:layout_width="0dp"
android:layout_height="0dp"
android:layout_marginTop="25dp"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintBottom_toTopOf="@+id/navigation"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent">
<include
layout="@layout/content_main"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_constraintBottom_toTopOf="@+id/navigation"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintTop_toTopOf="parent"
/>
</FrameLayout>
<!-- app:layout_constraintTop_toBottomOf="@+id/appBarLayout"-->
<!-- Bottom Navigation View -->
<com.google.android.material.bottomnavigation.BottomNavigationView
android:id="@+id/navigation"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginEnd="0dp"
android:layout_marginStart="0dp"
android:background="@color/colorPrimary"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:menu="@menu/navigation"
/>
</androidx.constraintlayout.widget.ConstraintLayout>
最佳答案
我发现了问题所在，由于某种原因，覆盖onCreateOptionsMenu对我来说不起作用，所以我找到了另一种方法：
toolbar2.getMenu().findItem(R.id.action_refresh).setVisible(false);
因此，就我而言，由于我想在特定片段处于活动状态时隐藏该项目，因此我创建了两个方法，并根据片段进行调用：
private void hideMenuItems(){
toolbar2.getMenu().findItem(R.id.action_refresh).setVisible(false);
toolbar2.getMenu().findItem(R.id.action_search).setVisible(false);
}
private void revealMenuItems(){
toolbar2.getMenu().findItem(R.id.action_refresh).setVisible(true);
toolbar2.getMenu().findItem(R.id.action_search).setVisible(true);
}