如何解决如何从登录屏幕中删除底部导航栏
ScreenShot of login screen with bottom navigation bar
嗨, 我在我的大学项目中遇到了一个问题。在上图中,您可以看到在我的登录屏幕中有一个底部导航栏,我想将其删除,但我尝试过的所有内容都以编译问题告终。 我的 MainActivity.KT 是
package com.example.integratedmodulateoroperationroom
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.view.Menu
import android.view.MenuItem
import androidx.navigation.NavController
import androidx.navigation.fragment.NavHostFragment
import androidx.navigation.fragment.findNavController
import androidx.navigation.ui.*
import kotlinx.android.synthetic.main.activity_main.*
class MainActivity : AppCompatActivity() {
private lateinit var navController: NavController
private lateinit var appBarConfiguration: AppBarConfiguration
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
val navHostFragment = supportFragmentManager.findFragmentById(R.id.nav_host_fragment) as NavHostFragment
navController = navHostFragment.findNavController()
appBarConfiguration = AppBarConfiguration(
setof(R.id.homeFragment,R.id.loginFragment),drawer_layout
)
setSupportActionBar(toolbar)
setupActionBarWithNavController(navController,appBarConfiguration)
bottom_nav.setupWithNavController(navController)
}
override fun onCreateOptionsMenu(menu: Menu?): Boolean {
menuInflater.inflate(R.menu.options_menu,menu)
return true
}
override fun onoptionsItemSelected(item: MenuItem): Boolean {
return item.onNavDestinationSelected(navController) || super.onoptionsItemSelected(item)
}
override fun onSupportNavigateUp(): Boolean {
return navController.navigateUp(appBarConfiguration) || super.onSupportNavigateUp()
}
}
Main_Activity.xml
<?xml version="1.0" encoding="utf-8"?>
<androidx.drawerlayout.widget.DrawerLayout
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:id="@+id/drawer_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
<androidx.constraintlayout.widget.ConstraintLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<androidx.appcompat.widget.Toolbar
android:id="@+id/toolbar"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="@color/design_default_color_primary"
android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:popupTheme="@style/ThemeOverlay.AppCompat.Light" />
<androidx.fragment.app.FragmentContainerView
android:id="@+id/nav_host_fragment"
android:name="androidx.navigation.fragment.NavHostFragment"
android:layout_width="match_parent"
android:layout_height="0dp"
app:defaultNavHost="true"
app:layout_constraintBottom_toTopOf="@+id/bottom_nav"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/toolbar"
app:navGraph="@navigation/nav_graph" />
<com.google.android.material.bottomnavigation.BottomNavigationView
android:id="@+id/bottom_nav"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:menu="@menu/bottom_nav_menu" />
</androidx.constraintlayout.widget.ConstraintLayout>
<com.google.android.material.navigation.NavigationView
android:id="@+id/nav_view"
android:layout_gravity="start"
app:menu="@menu/drawer_nav_menu"
android:layout_width="wrap_content"
android:layout_height="match_parent" />
</androidx.drawerlayout.widget.DrawerLayout>
登录片段.KT
package com.example.integratedmodulateoroperationroom
import android.os.Bundle
import android.view.View
import androidx.fragment.app.Fragment
import androidx.navigation.fragment.findNavController
import kotlinx.android.synthetic.main.fragment_login.*
class LoginFragment : Fragment (R.layout.fragment_login) {
override fun onViewCreated(view: View,savedInstanceState: Bundle?) {
super.onViewCreated(view,savedInstanceState)
button_goToHomeScreen.setonClickListener {
val action = LoginFragmentDirections.actionLoginFragmentToHomeFragment()
findNavController().navigate(action)
}
}
}
fragment_login
<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=".LoginFragment">
<EditText
android:id="@+id/editTextTextPersonName"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:ems="10"
android:hint="Login ID"
android:inputType="textPersonName"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<EditText
android:id="@+id/editTextTextPassword"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="16dp"
android:ems="10"
android:hint="Password"
android:inputType="textPassword"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/editTextTextPersonName" />
<Button
android:id="@+id/button_goToHomeScreen"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="24dp"
android:text="Login"
app:backgroundTint="#9E9E9E"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/editTextTextPassword" />
<ImageView
android:id="@+id/imageView4"
android:layout_width="0dp"
android:layout_height="274dp"
android:layout_marginStart="16dp"
android:layout_marginLeft="16dp"
android:layout_marginEnd="16dp"
android:layout_marginRight="16dp"
android:src="@drawable/logo"
app:layout_constraintBottom_toTopOf="@+id/editTextTextPersonName"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
导航图
<?xml version="1.0" encoding="utf-8"?>
<navigation 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:id="@+id/nav_graph"
app:startDestination="@id/homeFragment">
<fragment
android:id="@+id/homeFragment"
android:name="com.example.integratedmodulateoroperationroom.HomeFragment"
android:label="Integrated Module OR (Operation Room)"
tools:layout="@layout/fragment_home">
<action
android:id="@+id/action_homeFragment_to_otFragment"
app:destination="@id/otFragment"
app:enteranim="@anim/slide_in_right"
app:exitAnim="@anim/slide_out_left"
app:popEnteranim="@anim/slide_in_left"
app:popExitAnim="@anim/slide_out_right" />
<action
android:id="@+id/action_homeFragment_to_surgicalFragment"
app:destination="@id/surgicalFragment"
app:enteranim="@anim/slide_in_right"
app:exitAnim="@anim/slide_out_left"
app:popEnteranim="@anim/slide_in_left"
app:popExitAnim="@anim/slide_out_right" />
<action
android:id="@+id/action_homeFragment_to_laminarFragment"
app:destination="@id/laminarFragment" />
</fragment>
<fragment
android:id="@+id/otFragment"
android:name="com.example.integratedmodulateoroperationroom.OtFragment"
android:label="OT Lights"
tools:layout="@layout/fragment_ot" />
<fragment
android:id="@+id/surgicalFragment"
android:name="com.example.integratedmodulateoroperationroom.SurgicalFragment"
android:label="Surgical Lights"
tools:layout="@layout/fragment_surgical" />
<fragment
android:id="@+id/settingsFragment"
android:name="com.example.integratedmodulateoroperationroom.SettingsFragment"
android:label="Settings"
tools:layout="@layout/fragment_settings" />
<fragment
android:id="@+id/laminarFragment"
android:name="com.example.integratedmodulateoroperationroom.LaminarFragment"
android:label="Laminar Airflow"
tools:layout="@layout/fragment_laminar" />
<fragment
android:id="@+id/loginFragment"
android:name="com.example.integratedmodulateoroperationroom.LoginFragment"
android:label="Login"
tools:layout="@layout/fragment_login" >
<action
android:id="@+id/action_loginFragment_to_homeFragment"
app:destination="@id/homeFragment"
app:enteranim="@anim/slide_in_right"
app:exitAnim="@anim/slide_out_left"
app:popEnteranim="@anim/slide_in_left"
app:popExitAnim="@anim/slide_out_right" />
</fragment>
</navigation>
解决方法
您可以在活动的 onCreate 中执行类似操作。当导航栏中的某个项目被选中时,它将根据片段 ID 显示或隐藏导航。
private fun setupNav() {
val navController = findNavController(R.id.nav_host_fragment)
findViewById<BottomNavigationView>(R.id.bottomNav)
.setupWithNavController(navController)
navController.addOnDestinationChangedListener { _,destination,_ ->
when (destination.id) {
R.id.mainFragment -> showBottomNav()
R.id.mineFragment -> showBottomNav()
else -> hideBottomNav()
}
}
}
private fun showBottomNav() {
bottomNav.visibility = View.VISIBLE
}
private fun hideBottomNav() {
bottomNav.visibility = View.GONE
}
,
NavController
提供了一个 OnDestinationChangedListener
接口,当 NavController 的当前目标或其参数发生变化时会调用该接口,当您在片段之间导航时,该接口可用于更新 UI 元素,例如 BottomNavigationBar
。
MainActivity.KT
// in oncreate
private val bottomNavigationView = findViewById<BottomNavigationView>(R.id.bottom_nav)
navController.addOnDestinationChangedListener { _,_ ->
bottomNavigationView.visibility = if(destination.id == R.id.loginFragment) {
View.GONE
} else {
View.VISIBLE
}
}
版权声明:本文内容由互联网用户自发贡献,该文观点与技术仅代表作者本人。本站仅提供信息存储空间服务,不拥有所有权,不承担相关法律责任。如发现本站有涉嫌侵权/违法违规的内容, 请发送邮件至 dio@foxmail.com 举报,一经查实,本站将立刻删除。