How to write Android switching interface with kotlin

1. Create a new folder , Name it navigation, Then create a... Under this folder .xml file

2.layout In the catalog activity_main Code and rendering , Write a main page , Write a box inside that is easy to jump

<?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"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="com.fos.arfilemanager.activity.main.MainActivity">
    <fragment
        android:id="@+id/nav_host_container"
        android:name="androidx.navigation.fragment.NavHostFragment"
        android:layout_width="match_parent"
        app:layout_constraintBottom_toBottomOf="parent"
        android:layout_height="0dp"
        app:defaultNavHost="true"
        app:layout_constraintTop_toTopOf="@id/gl_h_09"
        app:navGraph="@navigation/nav_home"
        tools:layout="@layout/fragment_recently" />
    <androidx.constraintlayout.widget.Guideline
        android:id="@+id/gl_h_09"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:orientation="horizontal"
        app:layout_constraintGuide_percent="0.09" />

    <com.google.android.material.tabs.TabLayout
        android:id="@+id/tl"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:background="@color/black"
        app:layout_constraintBottom_toBottomOf="@+id/gl_h_09"
        app:layout_constraintTop_toTopOf="parent"
        app:tabIndicatorColor="@color/color_ff3877e0"
        app:tabIndicatorFullWidth="true"
        app:tabTextColor="@color/white">

        <com.google.android.material.tabs.TabItem
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@string/home_1" />

        <com.google.android.material.tabs.TabItem
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@string/home_2"
            />
    </com.google.android.material.tabs.TabLayout>


</androidx.constraintlayout.widget.ConstraintLayout>

3. stay Fragment Draw two pages that need to jump in the class

 ①recently Class is to write the initial page class

package com.fos.arfilemanager.fragment

import android.os.Bundle
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import com.fos.arfilemanager.databinding.FragmentRecentlyBinding

class RecentlyFragment :AbstractFileManagerFragment<FragmentRecentlyBinding>(){
    override fun bindObserver() {
        
    }

    override fun unbindObserver() {
        
    }

    override fun createViewBinding(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): FragmentRecentlyBinding {
        return FragmentRecentlyBinding.inflate(inflater,container,false)
    }

    override fun initView(view: View, savedInstanceState: Bundle?) {
        
    }

    override fun onRenderView() {
        
    }

    override fun onRestoreState(savedInstanceState: Bundle) {
        
    }

    override fun onSaveState(outState: Bundle) {
        
    }
}

②classfiy Class is the page that needs to jump later

package com.fos.arfilemanager.fragment

import android.graphics.BitmapFactory
import android.os.Bundle
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import androidx.recyclerview.widget.GridLayoutManager
import com.fos.arfilemanager.R
import com.fos.arfilemanager.adapter.ClassifyAdapter
import com.fos.arfilemanager.bean.ClassifyBean
import com.fos.arfilemanager.databinding.FragmentClassifyBinding

class ClassifyFragment :AbstractFileManagerFragment<FragmentClassifyBinding>(){
    private val classAdapter = ClassifyAdapter()
    override fun bindObserver() {
        
    }

    override fun unbindObserver() {
        
    }

    override fun createViewBinding(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): FragmentClassifyBinding {
        return FragmentClassifyBinding.inflate(inflater,container,false)
    }

    override fun initView(view: View, savedInstanceState: Bundle?) {
        val list:MutableList<ClassifyBean> = mutableListOf()
            list.add(ClassifyBean(R.mipmap.ic_picture,getString(R.string.classify_1)))
            list.add(ClassifyBean(R.mipmap.ic_video,getString(R.string.classify_2)))
            list.add(ClassifyBean(R.mipmap.ic_document,getString(R.string.classify_3)))
            list.add(ClassifyBean(R.mipmap.ic_voice,getString(R.string.classify_4)))
            list.add(ClassifyBean(R.mipmap.ic_application,getString(R.string.classify_5)))
            list.add(ClassifyBean(R.mipmap.ic_apk,getString(R.string.classify_6)))
//            list.add(ClassifyBean(getString(R.string.classify_2),"${R.mipmap.ic_video}"))
//            list.add(ClassifyBean(getString(R.string.classify_3),"${R.mipmap.ic_document}"))
//            list.add(ClassifyBean(getString(R.string.classify_4),"${R.mipmap.ic_video}"))
//            list.add(ClassifyBean(getString(R.string.classify_5),"${R.mipmap.ic_application}"))
//            list.add(ClassifyBean(getString(R.string.classify_6),"${R.mipmap.ic_apk}"))
        classAdapter.list = list
        bind.rvClassify.adapter = classAdapter
        bind.rvClassify.layoutManager = GridLayoutManager(requireContext(),3)
//        bind.vv.setImageBitmap(BitmapFactory.decodeFile("storage/emulated/0/DCIM/Camera/IMG_20220702_003011_0.jpg"))
    }

    override fun onRenderView() {
        
    }

    override fun onRestoreState(savedInstanceState: Bundle) {
        
    }

    override fun onSaveState(outState: Bundle) {
        
    }

}

4.navigation Under the folder nav_home.xml Document contents and renderings , Write the two switched pages

<?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_home"
    app:startDestination="@id/recentlyFragment">  // binding Fragment


    <fragment
        android:id="@+id/recentlyFragment"
        android:name="com.fos.arfilemanager.fragment.RecentlyFragment"
        android:label="RecentlyFragment"
        tools:layout="@layout/fragment_recently" />
    <fragment
        android:id="@+id/classifyFragment"
        android:name="com.fos.arfilemanager.fragment.ClassifyFragment"
        android:label="ClassifyFragment"
        tools:layout="@layout/fragment_classify" />

</navigation> 

 

5. stay activity.main Under folder MainActivity Write page logic ,RecyclerView Built in page number listener

 

package com.fos.arfilemanager.activity.main

import android.annotation.SuppressLint
import android.os.Bundle
import android.view.KeyEvent
import android.view.MotionEvent
import android.view.View
import android.widget.Toast
import androidx.appcompat.app.AppCompatActivity
import androidx.navigation.NavController
import androidx.navigation.findNavController
import androidx.navigation.fragment.findNavController
import com.fos.arfilemanager.R
import com.fos.arfilemanager.databinding.ActivityMainBinding
import com.google.android.material.tabs.TabLayout


class MainActivity : AppCompatActivity() {
    private lateinit var bind: ActivityMainBinding
    lateinit var navController:NavController
    companion object {
        private const val TAG = "MainActivity"
    }

    @SuppressLint("NewApi")
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        bind = ActivityMainBinding.inflate(layoutInflater)
      setContentView(bind.root)
        bind.tl.addOnTabSelectedListener(object :TabLayout.OnTabSelectedListener{
            override fun onTabSelected(tab: TabLayout.Tab?) {
                when(tab?.position){
                    0 ->{ findNavController(R.id.nav_host_container).navigate(R.id.recentlyFragment) }
                    1 ->{findNavController(R.id.nav_host_container).navigate(R.id.classifyFragment) }
                }
            }

            override fun onTabUnselected(tab: TabLayout.Tab?) {
            }

            override fun onTabReselected(tab: TabLayout.Tab?) {
            }

        })
    }

    interface OnKeyListener {
        fun dispatchKeyEvent(event: KeyEvent?): Boolean
    }

}