我有以下活动
class MainActivity : AppCompatActivity() {
private lateinit var drawerLayout: androidx.drawerlayout.widget.DrawerLayout
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.main_activity)
drawerLayout = drawer_layout
val navController = Navigation.findNavController(this,R.id.fragment_main_navHost)
setSupportActionBar(toolbar)
NavigationUI.setupActionBarWithNavController(this,navController,drawerLayout)
navView_main.setupWithNavController(navController)
}
override fun onSupportNavigateUp(): Boolean {
return NavigationUI.navigateUp(drawerLayout,Navigation.findNavController(this,R.id.fragment_main_navHost))
}
override fun onBackpressed() {
if (drawerLayout.isDrawerOpen(GravityCompat.START)) {
drawerLayout.closeDrawer(GravityCompat.START)
} else {
super.onBackpressed()
}
}
你可以看到它与导航图相关联,我正在使用导航抽屉.当我浏览抽屉中的项目时,我想保留汉堡图标,只有当我点击片段或弹出窗口中的项目时才将其更改为上/后按钮,并确保系统的行为反映了什么用户期望基于显示的图标.那可能吗
解决方法
按照以下步骤操作
1.绑定你的NavigationView with NavigationUI
NavigationUI.setupWithNavController(nav_view,hostFragment.navController)
2.绑定ActionBar With NavController
NavigationUI.setupActionBarWithNavController(this@NavActivity,hostFragment.navController)
3.绑定ActionBar and DrawerLayout With NavController
NavigationUI.setupActionBarWithNavController(this@NavActivity,hostFragment.navController,drawer_layout)
4.覆盖您活动中的onSupportNavigateUp()
override fun onSupportNavigateUp(): Boolean {
return NavigationUI.navigateUp(drawer_layout,hostFragment.navController)
|| super.onSupportNavigateUp()
}
样品：
class NavActivity : AppCompatActivity(),NavigationView.OnNavigationItemSelectedListener {
lateinit var hostFragment: NavHostFragment
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_nav)
setSupportActionBar(toolbar)
fab.setonClickListener { view ->
Snackbar.make(view,"Replace with your own action",Snackbar.LENGTH_LONG)
.setAction("Action",null).show()
}
val toggle = ActionBarDrawerToggle(
this,drawer_layout,toolbar,R.string.navigation_drawer_open,R.string.navigation_drawer_close)
drawer_layout.addDrawerListener(toggle)
toggle.syncState()
nav_view.setNavigationItemSelectedListener(this)
hostFragment = supportFragmentManager.findFragmentById(R.id.my_nav_host_fragment) as NavHostFragment
NavigationUI.setupWithNavController(nav_view,hostFragment.navController)
NavigationUI.setupActionBarWithNavController(this@NavActivity,drawer_layout)
}
override fun onBackpressed() {
if (drawer_layout.isDrawerOpen(GravityCompat.START)) {
drawer_layout.closeDrawer(GravityCompat.START)
} else {
super.onBackpressed()
}
}
override fun onSupportNavigateUp(): Boolean {
return NavigationUI.navigateUp(drawer_layout,hostFragment.navController) || super.onSupportNavigateUp()
}
override fun onCreateOptionsMenu(menu: Menu): Boolean {
// Inflate the menu; this adds items to the action bar if it is present.
menuInflater.inflate(R.menu.nav,menu)
return true
}
override fun onoptionsItemSelected(item: MenuItem): Boolean {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button,so long
// as you specify a parent activity in AndroidManifest.xml.
when (item.itemId) {
R.id.action_settings -> return true
else -> return super.onoptionsItemSelected(item)
}
}
override fun onNavigationItemSelected(item: MenuItem): Boolean {
// Handle navigation view item clicks here.
drawer_layout.closeDrawer(GravityCompat.START)
return true
}
}
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