我的 customCalendarView 的 InstantiationException

InstantiationException with my customCalendarView

我目前 运行 遇到一个错误,我的自定义日历视图不会 运行 在我的片段布局上。出于某种原因,我 运行 进入了这个 InstantiationException 错误,"java.lang.InstantiationException: The layout involves creation of com.example.road2success.CustomCalendarView over 100 levels deep. Infinite recursion?" 这就是实际错误所说的:

java.lang.InstantiationException: The layout involves creation of com.example.road2success.CustomCalendarView over 100 levels deep. Infinite recursion?
at org.jetbrains.android.uipreview.ViewLoader.loadClass(ViewLoader.java:181)
at org.jetbrains.android.uipreview.ViewLoader.loadView(ViewLoader.java:144)
at com.android.tools.idea.rendering.LayoutlibCallbackImpl.loadView(LayoutlibCallbackImpl.java:309)
at android.view.BridgeInflater.loadCustomView(BridgeInflater.java:418)
at android.view.BridgeInflater.loadCustomView(BridgeInflater.java:429)
at android.view.BridgeInflater.createViewFromTag(BridgeInflater.java:333)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:730)
at android.view.LayoutInflater.rInflate_Original(LayoutInflater.java:863)
at android.view.LayoutInflater_Delegate.rInflate(LayoutInflater_Delegate.java:72)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:837)
at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:824)
at android.view.LayoutInflater.inflate(LayoutInflater.java:515)
at android.view.LayoutInflater.inflate(LayoutInflater.java:423)
at com.example.road2success.CustomCalendarView.<init>(CustomCalendarView.kt:44)
at sun.reflect.GeneratedConstructorAccessor130.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
at org.jetbrains.android.uipreview.ViewLoader.createNewInstance(ViewLoader.java:403)
at org.jetbrains.android.uipreview.ViewLoader.loadClass(ViewLoader.java:186)
at org.jetbrains.android.uipreview.ViewLoader.loadView(ViewLoader.java:144)
at com.android.tools.idea.rendering.LayoutlibCallbackImpl.loadView(LayoutlibCallbackImpl.java:309)
at android.view.BridgeInflater.loadCustomView(BridgeInflater.java:418)
at android.view.BridgeInflater.loadCustomView(BridgeInflater.java:429)
at android.view.BridgeInflater.createViewFromTag(BridgeInflater.java:333)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:730)
at android.view.LayoutInflater.rInflate_Original(LayoutInflater.java:863)
at android.view.LayoutInflater_Delegate.rInflate(LayoutInflater_Delegate.java:72)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:837)
at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:824)
at android.view.LayoutInflater.inflate(LayoutInflater.java:515)
at android.view.LayoutInflater.inflate(LayoutInflater.java:423)
at com.example.road2success.CustomCalendarView.<init>(CustomCalendarView.kt:44)
at sun.reflect.GeneratedConstructorAccessor130.newInstance(Unknown Source)

(无法添加其余部分,但它只是一遍又一遍地重复)

我已经尝试了很多不同的方法来阻止无限递归,但我不确定到底是什么导致了这种情况,所以如果有人能帮我弄清楚那会很棒。错误语句中的第 44 行还引用了视图实例化(var view)。

CustomCalendarView.kt

package com.example.road2success

import android.annotation.SuppressLint
import android.app.AlertDialog
import android.content.Context
import android.database.Cursor
import android.database.sqlite.SQLiteDatabase
import android.util.AttributeSet
import android.util.Log.d
import android.view.LayoutInflater
import android.view.View
import android.widget.*
import androidx.annotation.Nullable
import androidx.core.content.getSystemService
import androidx.core.view.isVisible
import androidx.recyclerview.widget.LinearLayoutManager
import androidx.recyclerview.widget.RecyclerView
import java.text.SimpleDateFormat
import java.util.*
import kotlin.collections.ArrayList


class CustomCalendarView: LinearLayout{
    constructor(context: Context?):super(context)
    constructor(context: Context?, @Nullable attr: AttributeSet?):super(context, attr)
    var stuck = 1
    private var nextButton: ImageButton? = null
    private var prevButton: ImageButton? = null
    private var currentDate: TextView? = null
    private var grid: GridView? = null
    val maxDays = 42
    var calendar: Calendar = Calendar.getInstance(Locale.ENGLISH)
    var dates: ArrayList<Date> = ArrayList()
    var eventList: ArrayList<Events> = ArrayList()
    var dateFormat: SimpleDateFormat = SimpleDateFormat("MMMM yyyy", Locale.ENGLISH)
    var monthFormat: SimpleDateFormat = SimpleDateFormat("MMMM", Locale.ENGLISH)
    var yearFormat: SimpleDateFormat = SimpleDateFormat("yyyy", Locale.ENGLISH)
    var eventFormat: SimpleDateFormat = SimpleDateFormat("yyyy-MM-dd", Locale.ENGLISH)
    var myGrid: MyGridAdapter? = null

    init {
            var inflater=
                context!!.getSystemService(Context.LAYOUT_INFLATER_SERVICE) as LayoutInflater
            var view= inflater.inflate(R.layout.frag_home, this,true)
            nextButton = view.findViewById(R.id.rightButton)
            prevButton = view.findViewById(R.id.leftButton)
            currentDate = view.findViewById(R.id.dateText)
            grid = view.findViewById(R.id.calendar)
            prevButton?.setOnClickListener {
                calendar.add(Calendar.MONTH, -1)
                setUpCalendar()
            }
            nextButton?.setOnClickListener {
                calendar.add(Calendar.MONTH, 1)
                setUpCalendar()
            }
            grid?.setOnItemClickListener { adapterView: AdapterView<*>, view1: View, i: Int, l: Long ->
                var builder: AlertDialog.Builder = AlertDialog.Builder(context)
                builder.setCancelable(true)
                var addView: View =
                    LayoutInflater.from(context).inflate(R.layout.create_a_journey, null)
                var stages: Spinner = addView.findViewById(R.id.interview)
                var stageOther: EditText = addView.findViewById(R.id.stageother)
                var dText: EditText = addView.findViewById(R.id.dateText)
                var day = eventFormat.format(dates.get(i))
                var month = monthFormat.format(dates.get(i))
                var year = yearFormat.format(dates.get(i))
                dText.setText(day + "/" + month + "/" + year)
                var cText: EditText = addView.findViewById(R.id.company)
                var add: ImageButton = addView.findViewById(R.id.addButton)
                var cancel: ImageButton = addView.findViewById(R.id.cancelButton)
                var time: TimePicker = addView.findViewById(R.id.timeClock)
                var timeSet = EditText(context)
                var myAdapter: ArrayAdapter<String> = ArrayAdapter(
                    context,
                    android.R.layout.simple_list_item_1,
                    resources.getStringArray(R.array.stages)
                )
                myAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item)
                stages.adapter = myAdapter
                time.setOnTimeChangedListener { view, hourOfDay, minute ->
                    timeSet.setText(hourOfDay.toString() + ":" + minute.toString())
                }
                stages?.setOnClickListener {
                    stageOther.isVisible = stages?.selectedItem.equals("Other")
                }
                add?.setOnClickListener {
                    if (cText.text.isEmpty() || stages.selectedItem.equals(null)) {
                        Toast.makeText(
                            this.context,
                            "WARNING: Please fill in the stage and the company!",
                            Toast.LENGTH_LONG
                        ).show()
                    } else {
                        if (stages?.selectedItem.equals("Other")) {
                            saveEvent(
                                cText.toString(),
                                stageOther.toString(),
                                timeSet.toString(),
                                dText.toString(),
                                month.toString(),
                                year.toString()
                            )
                        } else {
                            saveEvent(
                                cText.toString(),
                                stages.selectedItem.toString(),
                                timeSet.toString(),
                                dText.toString(),
                                month.toString(),
                                year.toString()
                            )
                        }
                    }
                }
                cancel?.setOnClickListener {
                    Toast.makeText(this.context, "Canceled", Toast.LENGTH_LONG).show()
                }
                builder.setView(addView)
                builder.create()
                builder.show()
            }
            grid?.setOnItemLongClickListener { parent, view, position, id ->
                var date = eventFormat.format(dates.get(position))
                var builder: AlertDialog.Builder = AlertDialog.Builder(context)
                builder.setCancelable(true)
                var addView: View =
                    LayoutInflater.from(context).inflate(R.layout.showjourneys, null)
                var EventT: RecyclerView = addView.findViewById(R.id.eventsBoard)
                var layout: RecyclerView.LayoutManager = LinearLayoutManager(addView.context)
                EventT.layoutManager = layout
                EventT.setHasFixedSize(true)
                var EventTA = EventRecyclerView(CollectJourneys(date))
                EventT.adapter = EventTA
                EventTA.notifyDataSetChanged()

                builder.setView(addView)
                builder.create()
                builder.show()
                return@setOnItemLongClickListener true
            }
    }

    private fun CollectJourneys(date: String?): ArrayList<Events>{
        var aList: ArrayList<Events> = ArrayList()
        var db = DBHelper(context)
        var database: SQLiteDatabase = db.readableDatabase
        var cursor: Cursor? = db.ReadEvents(date,database)
        while(cursor?.moveToNext()!!){
            var company = cursor.getString(cursor.getColumnIndex(DBStructure.company))
            var stage = cursor.getString(cursor.getColumnIndex(DBStructure.stage))
            var time = cursor.getString(cursor.getColumnIndex(DBStructure.time))
            var date = cursor.getString(cursor.getColumnIndex(DBStructure.date))
            var month = cursor.getString(cursor.getColumnIndex(DBStructure.month))
            var year = cursor.getString(cursor.getColumnIndex(DBStructure.year))
            var event = Events(company,stage,time,date,month,year)
            aList.add(event)
        }
        cursor.close()
        database.close()
        return aList
    }


    private fun saveEvent(company:String?,stage:String?,time:String?, date:String?, month:String?, year:String?){
        var db = DBHelper(context)
        var database: SQLiteDatabase = db.writableDatabase
        db.saveEvent(company,stage,time,date,month,year,database)
        db.close()
        Toast.makeText(context,"Event Added", Toast.LENGTH_LONG).show()
    }
    private fun setUpCalendar() {
        var selectedDate = dateFormat.format(calendar.time)
        currentDate?.setText(selectedDate)
        dates.clear()
        var monthCalendar: Calendar = calendar.clone() as Calendar
        monthCalendar.set(Calendar.DAY_OF_MONTH,1)
        var firstDayOfMonth = monthCalendar.get(Calendar.DAY_OF_WEEK)-1
        monthCalendar.add(Calendar.DAY_OF_MONTH,-firstDayOfMonth)
        CollectEventsPerMonth(monthFormat.format(calendar.time),yearFormat.format(calendar.time))

        while(dates.size < maxDays){
            dates.add(monthCalendar.time)
            monthCalendar.add(Calendar.DAY_OF_MONTH,1)
        }
        myGrid = MyGridAdapter(context,dates,calendar,eventList)
        grid?.adapter = myGrid
    }
    private fun CollectEventsPerMonth(month: String?,year: String?){
        var db = DBHelper(context)
        var database: SQLiteDatabase = db.readableDatabase
        var cursor: Cursor? = db.ReadEventsPerMonth(year,month,database)
        while(cursor?.moveToNext()!!){
            var company = cursor.getString(cursor.getColumnIndex(DBStructure.company))
            var stage = cursor.getString(cursor.getColumnIndex(DBStructure.stage))
            var time = cursor.getString(cursor.getColumnIndex(DBStructure.time))
            var date = cursor.getString(cursor.getColumnIndex(DBStructure.date))
            var month = cursor.getString(cursor.getColumnIndex(DBStructure.month))
            var year = cursor.getString(cursor.getColumnIndex(DBStructure.year))
            var event = Events(company,stage,time,date,month,year)
            eventList.add(event)
        }
        cursor.close()
        database.close()
    }

}

frag_home.xml:

    <?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"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <com.example.road2success.CustomCalendarView
        android:id="@+id/customCalView"
        android:layout_width="0dp"
        android:layout_height="0dp"
        android:layout_marginTop="28dp"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.0"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />


</androidx.constraintlayout.widget.ConstraintLayout>

HomeFragment.kt:

package com.example.road2success.home

import android.os.Bundle
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import android.widget.TextView
import androidx.fragment.app.Fragment
import androidx.lifecycle.Observer
import androidx.lifecycle.ViewModelProviders
import com.example.road2success.CustomCalendarView
import com.example.road2success.R

class HomeFragment : Fragment() {
    override fun onCreateView(
        inflater: LayoutInflater,
        container: ViewGroup?,
        savedInstanceState: Bundle?
    ): View? {
        val root = inflater.inflate(R.layout.frag_home, container, false)
        val customCal: CustomCalendarView = root.findViewById(R.id.customCalView)

        return root
    }

}

MainActivity.kt(如果需要):

package com.example.road2success

import android.os.Bundle
import android.view.Menu
import androidx.navigation.findNavController
import androidx.navigation.ui.AppBarConfiguration
import androidx.navigation.ui.navigateUp
import androidx.navigation.ui.setupActionBarWithNavController
import androidx.navigation.ui.setupWithNavController
import androidx.drawerlayout.widget.DrawerLayout
import com.google.android.material.navigation.NavigationView
import androidx.appcompat.app.AppCompatActivity
import androidx.appcompat.widget.Toolbar

class MainActivity : AppCompatActivity() {

    private lateinit var appBarConfiguration: AppBarConfiguration
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        val toolbar: Toolbar = findViewById(R.id.toolBar)
        setSupportActionBar(toolbar)
        val drawerLayout: DrawerLayout = findViewById(R.id.drawMain)
        val navView: NavigationView = findViewById(R.id.NavView)
        val navController = findNavController(R.id.nav_host_fragment)
        // Passing each menu ID as a set of Ids because each
        // menu should be considered as top level destinations.
        appBarConfiguration = AppBarConfiguration(
            setOf(
                R.id.nav_home, R.id.nav_home_day, R.id.nav_home_month,
                R.id.nav_home_week, R.id.nav_home_year, R.id.nav_settings,
                R.id.nav_stats, R.id.nav_create), drawerLayout
        )
        setupActionBarWithNavController(navController, appBarConfiguration)
        navView.setupWithNavController(navController)
    }

    override fun onSupportNavigateUp(): Boolean {
        val navController = findNavController(R.id.nav_host_fragment)
        return navController.navigateUp(appBarConfiguration) || super.onSupportNavigateUp()
    }
}

再次感谢任何帮助,这是我的第一个 post 对于任何错误,我们深表歉意。

您的自定义 View 正在扩充包含您的自定义 View 实例的布局。所以:

  • 您创建了一个自定义实例 View(实例 #1)
  • 实例 #1 扩充创建自定义实例的布局 View(实例 #2)
  • 实例 #2 扩展了一个布局,它创建了一个自定义实例 View(实例 #3)
  • 实例 #3 扩展了一个布局,它创建了一个自定义实例 View(实例 #4)
  • 以此类推

由于您的布局被命名为 frag_home,并且由于它不包含您的自定义 View 期望的任何小部件,我猜您正在膨胀错误的布局。