在 Android 中更改片段时如何加速

How to speedup when change fragment in Android

为什么没有人帮助我???

在我的应用程序中,我使用 BottomNavBarNavigationGraph 来展示一些 fragments!
在我的一个 fragments 中,我有很多视图(fragment 布局有 1069 行 xml 代码)并且当 select 这个 fragment 来自 BottomNavBar,几秒钟后给我看这个 fragment
换句话说,给我看这个 fragment with delay!

片段代码:

class HomeDashboardFragment : Fragment(), HomeDashboardContracts.View {

    @NonNull
    private var pageTitle: TextView? = null
    @NonNull
    private var menuIcon: TextView? = null
    private lateinit var token: String
    private lateinit var presenter: HomeDashboardPresenterImpl
    private var giftExpireSplit: List<String> = emptyList()
    private var giftExpireDate: List<String> = emptyList()
    private var timeUtils: TimeUtils? = null
    @NonNull
    private var disposable: Disposable? = null

    override fun onCreateView(
        inflater: LayoutInflater, container: ViewGroup?,
        savedInstanceState: Bundle?
    ): View? {
        // Inflate the layout for this fragment
        return inflater.inflate(R.layout.fragment_home_dashboard, container, false)
    }

    @SuppressLint("WrongConstant")
    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
        super.onViewCreated(view, savedInstanceState)
        //Initialize
        presenter = HomeDashboardPresenterImpl(requireContext(), this)
        //Initialize views from activity
        activity?.let { itActivity ->
            pageTitle = itActivity.findViewById(R.id.toolbarMain_title)
            menuIcon = itActivity.findViewById(R.id.toolbarMain_menuIcon)
            //Set title
            pageTitle?.let { itTitle ->
                itTitle.text = getString(R.string.menuHomeDashboard)
            }
            //Open menu
            menuIcon?.let { itMenu ->
                itMenu.setOnClickListener {
                    itActivity.findViewById<AwesomeDrawerLayout>(R.id.homePage_drawerLayout).openDrawer(Gravity.END)
                }
            }
            //Get token
            token = GoodPrefs.getInstance().getString(PrefsKey.USER_JWT_TOKEN.name, "")
            //User registered
            if (GoodPrefs.getInstance().isKeyExists(PrefsKey.USER_JWT_TOKEN.name)) {
                menuIcon?.visibility = View.VISIBLE
            }
            //Set layout
            presenter.checkRegisterUser(token)
            //Load profile data
            if (!isEmptyString(token)) {
                presenter.getProfile(token, USER_NOTIF_ID)
            }
        }
    }

MainActivity 代码集 fragmentsBottomNavBar with NavigationGraph :

private fun setupNavigation() {
    val navController = Navigation.findNavController(this, R.id.homePage_fragmentNavHost)
    NavigationUI.setupWithNavController(homePage_bottomNavBar, navController)
}

override fun onSupportNavigateUp() = Navigation.findNavController(this, R.id.homePage_fragmentNavHost).navigateUp()

我该如何解决这个问题?

您可以添加由单个 viewGroup 组成的布局虚拟对象。然后在 onViewCreated 方法中膨胀真正的布局。例如:

override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?) =
       inflater.inflate(R.layout.layout_dummy, container, false);

override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
        super.onViewCreated(view, savedInstanceState)

        Handler().post {
            val layout = flContainer
            val child = layoutInflater.inflate(R.layout.fragment_real, null)
            layout.removeAllViews()
            layout.addView(child)

            setupToolbar()
            setupWebView()
        }
    }


layout_dummy.xml
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout
        android:id="@+id/flContainer"
        xmlns:android="http://schemas.android.com/apk/res/android"
        android:orientation="vertical"
        android:layout_width="match_parent"
        android:layout_height="match_parent">

</FrameLayout>

您的问题几乎可以肯定是由您庞大的 XML 文件引起的。加载所有这些视图需要时间。你有很多嵌套会减慢速度。

你必须优化你的布局。删除不需要的东西。用 ConstraintLayout 替换尽可能多的嵌套 LinearLayout。如果这是一个长的滚动视图,可以使用 RecyclerView。

希望对您有所帮助。