您好,我在主要活动中添加了底部导航,其余所有布局都是片段,现在我有一个登录片段,我不想显示底部导航,我什至不想单独将底部导航包含到每个片段中,有什么方法可以禁用某些片段中的底部导航,例如登录片段
<块引用>如果您需要更多参考,请告诉我我会更新问题
Main_Activity.java
public class MainActivity extends AppCompatActivity {
BottomNavigationView bottomNavigationView;
Deque<Integer> integerDeque = new ArrayDeque<>(4);
boolean flag = true;
@RequiresApi(api = Build.VERSION_CODES.LOLLIPOP)
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
AppCompatDelegate.setDefaultNightMode(AppCompatDelegate.MODE_NIGHT_NO);
setContentView(R.layout.activity_main);
Window window = this.getWindow();
window.setStatusBarColor(this.getResources().getColor(R.color.black));
bottomNavigationView = findViewById(R.id.bottom_navigation_view);
integerDeque.push(R.id.nav_home);
loadFragments(new Home_Fragment());
bottomNavigationView.setSelectedItemId(R.id.nav_home);
bottomNavigationView.setOnNavigationItemSelectedListener(
item -> {
int id = item.getItemId();
if (integerDeque.contains(id)) {
if (id == R.id.nav_home) {
integerDeque.size();
if (flag) {
integerDeque.addFirst(R.id.nav_home);
flag = false;
}
}
integerDeque.remove(id);
}
integerDeque.push(id);
loadFragments(getFragment(item.getItemId()));
return false;
}
);
}
@SuppressLint("NonConstantResourceId")
private Fragment getFragment(int itemId) {
switch (itemId) {
case R.id.nav_home:
bottomNavigationView.getMenu().getItem(0).setChecked(true);
return new Home_Fragment();
case R.id.nav_following:
bottomNavigationView.getMenu().getItem(1).setChecked(true);
return new Following_Fragment();
case R.id.nav_upload:
bottomNavigationView.getMenu().getItem(2).setChecked(true);
return new Upload_Fragment();
case R.id.nav_notification:
bottomNavigationView.getMenu().getItem(3).setChecked(true);
return new Notification_Fragment();
case R.id.nav_profile:
bottomNavigationView.getMenu().getItem(4).setChecked(true);
return new Profile_Fragment();
}
bottomNavigationView.getMenu().getItem(0).setChecked(true);
return new Home_Fragment();
}
public void loadFragments(Fragment fragment) {
if (fragment != null) {
getSupportFragmentManager().beginTransaction()
.replace(R.id.fragment_container, fragment, fragment.getClass().getSimpleName())
.commit();
}
}
@Override
public void onBackPressed() {
integerDeque.pop();
if (!integerDeque.isEmpty()) {
loadFragments(getFragment(integerDeque.peek()));
} else {
finish();
}
}
}
Update 1 // 根据答案添加 login_fragment 但它不起作用
Login_Fragment.java
public class Login_Fragment extends Fragment {
@Nullable
@org.jetbrains.annotations.Nullable
@Override
public View onCreateView(@NonNull LayoutInflater inflater, @Nullable @org.jetbrains.annotations.Nullable ViewGroup container, @Nullable @org.jetbrains.annotations.Nullable Bundle savedInstanceState) {
return inflater.inflate(R.layout.login_fragment, container, false);
if (getActivity() != null && getActivity() instanceof MainActivity)
((MainActivity) getActivity()).bottomNavigationView.setVisibility(View.GONE);
}
}
更新一、二方法错误
error: unreachable statement
if (getActivity() != null && getActivity() instanceof MainActivity)
^
答案 0 :(得分:2)
您可以在片段中执行以下操作:
BottomNavigationView navBar = getActivity().findViewById(R.id.bottomBar);
navBar.setVisiblity(View.GONE);
或
public class Login_Fragment extends Fragment {
@Nullable
@org.jetbrains.annotations.Nullable
@Override
public View onCreateView(@NonNull LayoutInflater inflater, @Nullable @org.jetbrains.annotations.Nullable ViewGroup container, @Nullable @org.jetbrains.annotations.Nullable Bundle savedInstanceState) {
if (getActivity() != null && getActivity() instanceof MainActivity)
((MainActivity) getActivity()).bottomNavigationView.setVisibility(View.GONE);
return inflater.inflate(R.layout.login_fragment, container, false);
}
}