I am developing android news app using bottomnavigation view but when I run the app I am getting following exception
Process: yodgorbek.komilov.musobaqayangiliklari, PID: 19590
java.lang.RuntimeException: Unable to start activity ComponentInfo{yodgorbek.komilov.musobaqayangiliklari/yodgorbek.komilov.musobaqayangiliklari.MainActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'void com.google.android.material.bottomnavigation.BottomNavigationView.setOnNavigationItemSelectedListener(com.google.android.material.bottomnavigation.BottomNavigationView$OnNavigationItemSelectedListener)' on a null object reference`
below MainActivity.kt
class MainActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
val bottomNavigationView = findViewById<BottomNavigationView>(R.id.bottom)
bottomNavigationView.setOnNavigationItemSelectedListener {
var selectedFragment = Fragment()
when (it.itemId) {
R.id.top_headline -> selectedFragment = TopHeadlinesFragment()
R.id.espn_news -> selectedFragment = ESPNFragment()
R.id.bbc_sport -> selectedFragment = BBCSportFragment()
R.id.football_italia -> selectedFragment = FootballItaliaFragment()
}
val transaction = supportFragmentManager.beginTransaction()
transaction.replace(R.id.frame_layout, selectedFragment)
transaction.commit()
return#setOnNavigationItemSelectedListener true
}
}
}
below activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout 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">
<com.google.android.material.bottomnavigation.BottomNavigationView
android:layout_gravity="bottom"
app:menu="#menu/bottomnews_nav"
android:layout_width="match_parent"
android:layout_height="wrap_content"/>
</FrameLayout>
In your layout there is no id for the bottomNavigationView nor the framelayout.Add id's for both of them
Related
I am trying to display notes in my recycler view. the note body is like this:
Note Title in one text view
Note Content in the other text view below the title
So, this will get displayed in one Item and then the next note in the next item. But the issue is that,
one item is containing the note title, and the other one is containing its content.
Here is my NotesAdapter Class:
class NotesAdapter(private var noteView: ArrayList<String>):
RecyclerView.Adapter<NotesAdapter.MyViewHolder>() {
inner class MyViewHolder(noteView: View) : RecyclerView.ViewHolder(noteView)
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): MyViewHolder {
val noteView : View =LayoutInflater.from(parent.context).inflate(R.layout.note_card,parent,false)
return MyViewHolder(noteView)
}
override fun onBindViewHolder(holder: MyViewHolder, position: Int) {
//Set data here
holder.itemView.apply {
note_title_TV.text = noteView[position]
note_content_TV.text = noteView[position]
}
}
override fun getItemCount(): Int {
return noteView.size
}
}
My Main Activity Class (This class contains my firebase code too, as I am reading data from there and storing that into a list) :
class HomeActivity : AppCompatActivity() {
var nList = ArrayList<String>();
private lateinit var recyclerView: RecyclerView
private lateinit var viewAdapter: RecyclerView.Adapter<*>
private lateinit var viewManager: RecyclerView.LayoutManager
val rootReference = Firebase.database.reference //app root in firebase database
val currentUser = FirebaseAuth.getInstance().currentUser
val uid = currentUser?.uid.toString()
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_home)
//Show user's name in welcome message
//get the name of user from firebase
val nameFromFirebase: FirebaseDatabase = FirebaseDatabase.getInstance()
var nameReference = rootReference.child("users").child(uid).child("name")
nameReference.addListenerForSingleValueEvent(object : ValueEventListener {
override fun onDataChange(snapshot: DataSnapshot) {
val result = snapshot.value
tv_User_Name.text = result.toString()
}
override fun onCancelled(error: DatabaseError) {
TODO("Not yet implemented")
}
})
btn_createNote.setOnClickListener {
Intent(this, AddNoteActivity::class.java).also {
startActivity(it)
}
}
//Read notes from database
readNotesFromFirebaseDatabase()
//Updating Layout to display notes in RecyclerView
recyclerView = findViewById<RecyclerView>(R.id.rv_displayNotesInRecyclerView)
recyclerView.setHasFixedSize(true)
recyclerView.layoutManager=LinearLayoutManager(this)
//RecyclerView Adapter being passed the notes list
val adapter = NotesAdapter(nList)
rv_displayNotesInRecyclerView.adapter = adapter
}
fun readNotesFromFirebaseDatabase(){
val noteReference = rootReference.child("users").child(uid).child("Notes")
noteReference.addValueEventListener(object:ValueEventListener{
override fun onDataChange(snapshot: DataSnapshot) {
val noteContent = snapshot.child("noteContent").getValue(String::class.java)
val noteTitle = snapshot.child("noteTitle").getValue(String::class.java)
//Add Notes to the ArrayList of Notes
nList.add(noteTitle.toString())
nList.add(noteContent.toString())
}
override fun onCancelled(error: DatabaseError) {
TODO("Not yet implemented")
}
})
}
}
Note_item XML Layout File:
<?xml version="1.0" encoding="UTF-8"?>
<androidx.coordinatorlayout.widget.CoordinatorLayout 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="wrap_content">
<androidx.cardview.widget.CardView
android:id="#+id/prompt_cardview"
android:layout_width="390dp"
android:layout_height="89dp"
android:layout_marginLeft="10dp"
android:layout_marginTop="5dp"
android:layout_marginRight="10dp"
android:layout_marginBottom="10dp"
android:minHeight="120dp"
app:cardCornerRadius="15dp"
app:cardElevation="3dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent">
<androidx.constraintlayout.widget.ConstraintLayout
android:layout_width="384dp"
android:layout_height="match_parent"
android:minHeight="120dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="1.0"
app:layout_constraintTop_toTopOf="parent">
<TextView
android:id="#+id/note_title_TV"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="16dp"
android:layout_marginEnd="8dp"
android:fontFamily="#font/lato"
android:lineHeight="22dp"
android:text="Title"
android:textAlignment="gravity"
android:textColor="#4F4B4B"
android:textSize="18sp"
android:textStyle="bold"
android:paddingLeft="2dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.037"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintVertical_bias="0.0" />
<TextView
android:id="#+id/note_content_TV"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_margin="8dp"
android:layout_marginStart="12dp"
android:layout_marginTop="10dp"
android:layout_marginEnd="8dp"
android:fontFamily="#font/lato"
android:paddingLeft="5dp"
android:lineHeight="14dp"
android:singleLine="false"
android:text="#string/some_comments_are_here_to_stay_you_know"
android:textAlignment="center"
android:textColor=" #877B7B"
android:textSize="12sp"
android:textStyle="bold"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.0"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/note_title_TV"
app:layout_constraintVertical_bias="0.0" />
<ImageButton
android:id="#+id/btn_edit"
android:layout_width="25dp"
android:layout_height="25dp"
android:layout_marginTop="8dp"
android:layout_marginBottom="8dp"
android:background="#drawable/round_button_edit"
android:src="#drawable/icon_btn_edit"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toStartOf="#+id/btn_delete"
app:layout_constraintHorizontal_bias="0.972"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/note_content_TV"
app:layout_constraintVertical_bias="1.0" />
<ImageButton
android:id="#+id/btn_delete"
android:layout_width="25dp"
android:layout_height="25dp"
android:layout_marginTop="8dp"
android:layout_marginBottom="8dp"
android:background="#drawable/round_button_delete"
android:src="#drawable/icon_btn_delete"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.983"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/note_content_TV"
app:layout_constraintVertical_bias="1.0" />
</androidx.constraintlayout.widget.ConstraintLayout>
</androidx.cardview.widget.CardView>
</androidx.coordinatorlayout.widget.CoordinatorLayout>
I Also have made a Note Class (if it may be of any assistance) :
class Note (val noteContent:String , val noteTitle: String) {
}
This is my Firebase Database Note Entry, 1:https://i.stack.imgur.com/bixCW.png
Now, I am getting this output, 2: https://i.stack.imgur.com/VV7l7.png
P.S I know there are some posts regarding this like this one: How to create Multiple View Type in Recycler View but they are in Java and I am getting stuck while converting that here.
Try this:
Create a model class with 2 variables
class Notes{
val title: String = ""
val content: String = ""
}
after that creates an array list using that model class instead of String which looks like this:
val list: MutableList<Notes> = Notes()
val nots : Notes = Notes()
notes.title = "test"
notes.content = "Good Work!"
list.add(notes)
Once your list is created pass that list to adapter and you are good to go
class NotesAdapter(private var list: ArrayList<Note>):
RecyclerView.Adapter<NotesAdapter.MyViewHolder>() {
inner class MyViewHolder(noteView: View) : RecyclerView.ViewHolder(noteView)
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): MyViewHolder {
val noteView : View = LayoutInflater.from(parent.context).inflate(R.layout.note_card,parent,false)
return MyViewHolder(noteView)
}
override fun onBindViewHolder(holder: MyViewHolder, position: Int) {
holder.itemView.apply {
note_title_TV.text = list[position].title
note_content_TV.text = list[position].content
}
}
override fun getItemCount(): Int {
return list.size
}
}
The problem is solved.
Change the ArrayList from String to Note
And in the Main Activity Class, edited this block of code:
//Add Notes to the ArrayList of Notes
var note : Note
note.noteContent = noteTitle.toString()
note.noteTitle = noteTitle.toString()
In the NotesAdapter Class (Posting the complete correct code):
class NotesAdapter(private var noteView: ArrayList<Note>):
RecyclerView.Adapter<NotesAdapter.MyViewHolder>() {
inner class MyViewHolder(noteView: View) : RecyclerView.ViewHolder(noteView)
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): MyViewHolder {
val noteView : View = LayoutInflater.from(parent.context).inflate(R.layout.note_card,parent,false)
return MyViewHolder(noteView)
}
override fun onBindViewHolder(holder: MyViewHolder, position: Int) {
//Set data here
holder.itemView.apply {
note_title_TV.text = noteView[position].noteContent
note_content_TV.text = noteView[position].noteTitle
}
}
override fun getItemCount(): Int {
return noteView.size
}
}
Am trying to use a spinner in a layout. I can add and select items to the spinner but I cannot retrieve the selected item. This is the main activity:
class pageNewPurchaseOrder : AppCompatActivity() {
lateinit var spinnerVendorX: androidx.appcompat.widget.AppCompatSpinner
var spinnerArray: java.util.ArrayList<CharSequence> = ArrayList<CharSequence>()
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_page_new_purchase_order)
setSupportActionBar(toolbar)
supportActionBar?.setDisplayShowTitleEnabled(false)
spinnerVendorX = findViewById(R.id.spinnerVendorX)
spinnerVendorX.adapter = ArrayAdapter(this#pageNewPurchaseOrder, android.R.layout.simple_spinner_item, spinnerArray)
spinnerVendorX.onItemSelectedListener = object : AdapterView.OnItemSelectedListener {
override fun onNothingSelected(parent: AdapterView<*>?) {
}
override fun onItemSelected(parent: AdapterView<*>?, view: View?, position: Int, id: Long) {
Log.d("aaa", "This code is not running!")
}
}
}
}
This is the layout activity
<?xml version="1.0" encoding="utf-8"?>
<androidx.core.widget.NestedScrollView 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"
android:background="?attr/colorPrimary"
android:fillViewport="true"
android:focusable="true"
android:focusableInTouchMode="true"
app:layout_behavior="#string/appbar_scrolling_view_behavior"
tools:context=".pageNewPurchaseOrder"
tools:showIn="#layout/activity_page_new_purchase_order">
<androidx.appcompat.widget.AppCompatSpinner
android:padding="10dp"
android:background="#drawable/bgselect"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="10dp"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toBottomOf="#+id/lbl2"
android:id="#+id/spinnerVendorX" />
</androidx.core.widget.NestedScrollView>
Am getting result this on the logcat when I select an item: E/ViewRootImpl(31835): sendUserActionEvent() mView == null.I get tj=he same results even when I use <Spinner instead of <androidx.appcompat.widget.AppCompatSpinner
User must have to add data in the ArrayList. Here, you are initialising arrayList and set it but not adding data in ArrayList. Please add data in ArrayList then try it. Thank you.
THIS IS MY XML
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
xmlns:app="http://schemas.android.com/apk/res-auto"
tools:context=".MakeComplaint.Category_Description"
android:background="#drawable/fragmentgradient_bg">
<androidx.constraintlayout.widget.ConstraintLayout
android:id="#+id/heading_constraint"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
tools:layout_editor_absoluteX="17dp">
<ImageView
android:id="#+id/backToHistory"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:paddingHorizontal="20dp"
android:layout_weight="2"
android:src="#drawable/ic_backarrow"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintRight_toLeftOf="#+id/location_title"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<TextView
android:id="#+id/location_title"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:paddingHorizontal="20dp"
android:fontFamily="#font/pathway_gothic_one"
android:gravity="center"
android:textSize="40sp"
android:text="Further Details"
app:layout_constraintHorizontal_bias="0.35"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintLeft_toRightOf="#+id/backToHistory"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
<androidx.cardview.widget.CardView
android:id="#+id/details_card"
android:layout_width="0dp"
android:layout_height="0dp"
android:elevation="#dimen/card_spacing"
app:cardUseCompatPadding="true"
app:layout_constraintTop_toBottomOf="#+id/heading_constraint"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintBottom_toBottomOf="parent"
app:cardCornerRadius="#dimen/card_spacing"
>
<ScrollView
android:id="#+id/scroll"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fillViewport="true">
<androidx.constraintlayout.widget.ConstraintLayout
android:id="#+id/inner_constraint"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:padding="#dimen/card_spacing">
<TextView
android:id="#+id/guide"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:fontFamily="#font/pathway_gothic_one"
android:gravity="left"
android:text="Please enter any further details you would like to add:"
android:textSize="20sp"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<com.google.android.material.textfield.TextInputLayout
android:id="#+id/description_text_input"
style="#style/Widget.MaterialComponents.TextInputLayout.OutlinedBox"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="20dp"
app:boxStrokeColor="#color/teal"
app:boxStrokeWidth="#dimen/card_spacing"
app:counterEnabled="true"
app:counterMaxLength="500"
android:hint="Additional Notes"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toBottomOf="#id/guide"
app:prefixTextColor="#color/colorPrimaryDark"
android:outlineAmbientShadowColor="#color/teal"
android:outlineSpotShadowColor="#color/teal"
android:scrollbarAlwaysDrawHorizontalTrack="true"
app:layout_constraintBaseline_creator="#android:integer/config_longAnimTime"
>
<com.google.android.material.textfield.TextInputEditText
android:id="#+id/description"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:inputType="textCapSentences|textMultiLine"
android:maxLength="500"
/>
</com.google.android.material.textfield.TextInputLayout>
<!--ImageView where image will be set-->
<ImageView
android:id="#+id/display_image"
android:scaleType="centerCrop"
android:layout_width="250dp"
android:layout_height="250dp"
android:adjustViewBounds="true"
app:layout_constraintTop_toBottomOf="#+id/description_text_input"
app:layout_constraintBottom_toTopOf="#+id/FAB_buttons"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintLeft_toLeftOf="parent"/>
<androidx.appcompat.widget.LinearLayoutCompat
android:id="#+id/FAB_buttons"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:layout_constraintTop_toBottomOf="#+id/description_text_input"
app:layout_constraintRight_toRightOf="parent"
android:layout_marginVertical="5dp">
<com.google.android.material.floatingactionbutton.FloatingActionButton
android:id="#+id/camera"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_margin="16dp"
app:backgroundTint="#color/teal"
android:layout_marginHorizontal="#dimen/card_spacing"
android:src="#android:drawable/ic_menu_camera"
app:layout_constraintRight_toLeftOf="#+id/camera"
app:layout_constraintTop_toBottomOf="#+id/name_text_input"
/>
<com.google.android.material.floatingactionbutton.FloatingActionButton
android:id="#+id/upload"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_margin="16dp"
app:backgroundTint="#color/teal"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toBottomOf="#+id/name_text_input"
android:src="#android:drawable/ic_menu_gallery"
/>
</androidx.appcompat.widget.LinearLayoutCompat>
<com.google.android.material.button.MaterialButton
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Make Complaint"
app:layout_constraintTop_toBottomOf="#+id/FAB_buttons"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:backgroundTint="#color/teal"
/>
</androidx.constraintlayout.widget.ConstraintLayout>
</ScrollView>
</androidx.cardview.widget.CardView>
</androidx.constraintlayout.widget.ConstraintLayout>```
**THIS IS MY KOTLIN FILE**
package com.example.atry.MakeComplaint
class Category_Description : Fragment() {
private val ALL_PERMISSIONS_RESULT = 107
private val IMAGE_RESULT = 200
private val REQUEST_IMAGE_CAPTURE = 12345
var mBitmap: Bitmap? = null
val permission = 1
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
arguments?.let {
}
}
override fun onCreateView(
inflater: LayoutInflater, container: ViewGroup?,
savedInstanceState: Bundle?
): View? {
// Inflate the layout for this fragment
val v = inflater.inflate(com.example.atry.R.layout.fragment_category__description, container, false)
val camera_FAB: View = v.findViewById(com.example.atry.R.id.camera)
val upload_FAB: View = v.findViewById(com.example.atry.R.id.upload)
val imageView = v.findViewById<ImageView>(com.example.atry.R.id.display_image)
upload_FAB.setOnClickListener {
pickImageFromGallery()
}
camera_FAB.setOnClickListener{
val intent = Intent(MediaStore.ACTION_IMAGE_CAPTURE)
val frag = this
/** Pass your fragment reference **/
frag.startActivityForResult(
intent,
REQUEST_IMAGE_CAPTURE
) // REQUEST_IMAGE_CAPTURE = 12345
}
fun hasPermissionInManifest(context: Context, permissionName: String): Boolean {
val packageName = context.packageName
try {
val packageInfo = context.packageManager
.getPackageInfo(packageName, PackageManager.GET_PERMISSIONS)
val declaredPermisisons = packageInfo.requestedPermissions
if (declaredPermisisons != null && declaredPermisisons.size > 0) {
for (p in declaredPermisisons) {
if (p == permissionName) {
return true
}
}
}
} catch (e: PackageManager.NameNotFoundException) {
}
return false
}
v.backToHistory.setOnClickListener {
backFragment()
}
// Inflate the layout for this fragment
return v
}
private fun pickImageFromGallery() {
//Intent to pick image
val intent = Intent(Intent.ACTION_PICK)
intent.type = "image/*"
startActivityForResult(intent, IMAGE_PICK_CODE)
}
companion object {
//image pick code
private val IMAGE_PICK_CODE = 1000;
//Permission code
private val PERMISSION_CODE = 1001;
}
private fun backFragment() {
val manager = (context as AppCompatActivity).supportFragmentManager
manager.popBackStackImmediate()
}
override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
super.onActivityResult(requestCode, resultCode, data)
if (resultCode == Activity.RESULT_OK && data !=null) {
if (requestCode == REQUEST_IMAGE_CAPTURE || requestCode== IMAGE_PICK_CODE) {
// Do something with imagePath
val extras = data.getExtras()
val photo = extras.get("data") as Bitmap
val imageView = view!!.findViewById<ImageView>(com.example.atry.R.id.display_image)
imageView.setImageBitmap(photo)
// CALL THIS METHOD TO GET THE URI FROM THE BITMAP
var selectedImage = activity.let { getImageUri( it!!,photo) }
val realPath = selectedImage.let { getRealPathFromURI(it) }
selectedImage = Uri.parse(realPath)
}
}
super.onActivityResult(requestCode, resultCode, data)
}
fun getImageUri(inContext: Context, inImage: Bitmap): Uri {
val bytes = ByteArrayOutputStream()
inImage.compress(Bitmap.CompressFormat.JPEG, 100, bytes)
val path =
MediaStore.Images.Media.insertImage(inContext.contentResolver, inImage, "Title", null)
return Uri.parse(path)
}
fun getRealPathFromURI(contentUri: Uri): String {
var cursor: Cursor? = null
try {
val proj = arrayOf(MediaStore.Images.Media.DATA)
cursor = getActivity()?.getContentResolver()?.query(contentUri, proj, null, null, null)
val column_index = cursor!!.getColumnIndexOrThrow(MediaStore.Images.Media.DATA)
cursor!!.moveToFirst()
return cursor!!.getString(column_index)
} finally {
if (cursor != null) {
cursor!!.close()
}
}
}
}```
For capturing the image everything works fine until the screen appears where I click on the tick to approve that the picture is okay...but then I am unable to view anything on the ImageView.
For the upload button when I am on the screen that allows me to select the picture ...when i click on it the app crashes and gives me the following error: java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.Object android.os.Bundle.get(java.lang.String)' on a null object reference
I have searched the internet for days and couldn't find a proper solution to this. I would appreciate it if anyone could find me a solution to this.
URI of the selected image is not returned in Intent extras, but in the data of intent. You can get the selected image's URI as follows.
override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
super.onActivityResult(requestCode, resultCode, data)
if (resultCode == Activity.RESULT_OK && data !=null) {
if (requestCode == REQUEST_IMAGE_CAPTURE || requestCode== IMAGE_PICK_CODE) {
// Get image URI From intent
var imageUri = data.data
// do something with the image URI
your_image_view.setImageURI(imageUri)
}
}
super.onActivityResult(requestCode, resultCode, data)
}
I'm new to Kotlin and im trying to build a HomePage where there is a BottomNavigation with 3 Fragment pages but in 1 of the pages I set a ListView and whenever I call the ID it gives the following errer(Caused by: java.lang.IllegalStateException: categoryListView must not be null)
Here is how Im calling it in my HomePage which is where the content appears:
class HomePage : AppCompatActivity(), NavigationView.OnNavigationItemSelectedListener {
lateinit var adapter : CategoryAdapter
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_home_page)
adapter = CategoryAdapter(this, DataService.categories)
categoryListView.adapter = adapter
navView.setNavigationItemSelectedListener(this)
bottomNavigation.setOnNavigationItemSelectedListener(mOnNavigationItemSelectedListener)
replaceFragment(HomeFragment())
}
private val mOnNavigationItemSelectedListener = BottomNavigationView.OnNavigationItemSelectedListener { item ->
when(item.itemId) {
R.id.Bottom_Nav_Home -> {
println("Home pressed")
replaceFragment(HomeFragment())
return#OnNavigationItemSelectedListener true
}
R.id.Bottom_Nav_Notifs -> {
println("Notification pressed")
replaceFragment(NotifsFragment())
return#OnNavigationItemSelectedListener true
}
R.id.Bottom_Nav_List -> {
println("List pressed")
replaceFragment(ListFragment())
return#OnNavigationItemSelectedListener true
}
}
false
}
private fun replaceFragment(fragment: Fragment) {
val fragmentTransaction = supportFragmentManager.beginTransaction()
fragmentTransaction.replace(R.id.NavPageFragment, fragment)
fragmentTransaction.commit()
}
}
am I doing it correct? or am I supposed to call the categoryListView elsewhere? because I tried in my ListFragment which is where my activity code is and it gave a context error
here is how the Fragment activity looks:
<?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:id="#+id/Bottom_List"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".Fragments.ListFragment">
<ListView
android:id="#+id/categoryListView"
android:layout_width="wrap_content"
android:layout_height="0dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
You are trying to get the categoryListView resolved inside the activity but it is (as far as I understand) part of the fragment. This simply does not work.
The CategoryAdapter and the ListView should be used inside your HomeFragment class and this will work then.
So move this code into your fragment:
adapter = CategoryAdapter(this, DataService.categories)
categoryListView.adapter = adapter
Update
I would move it into the onViewCreated() method. There you can simply rely on the fact that there is a view available with a context.
override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
adapter = CategoryAdapter(view.context, DataService.categories)
categoryListView.adapter = adapter // categoryListView will be not null here
}
How can I replace the fragment when i click on an item inside a recyclerView
I've tried inside onClickListener of adapter
childFragmentManager
.beginTransaction()
.replace(R.id.framefragment2, Fragment2())
.commit()
with no succes it returns me
java.lang.IllegalArgumentException: No view found for id 0x7f0a0137 (com.test.justaapp:id/framefragment1) for fragment Fragmetnone{1ebd5fc #0 id=0x7f0a0137}
Here is mi xml of 1st fragment already inflated
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="#+id/framefragment1"
android:layout_width="match_parent"
android:layout_height="match_parent">
and the second frame layout
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#C0C0C0">
<FrameLayout
android:id="#+id/framefragment2"
android:layout_width="match_parent"
android:layout_height="match_parent">
I've been searching for hours and can't get it to work, any ideas? maybe I'm mimssing something very simple, any help would be apreciated Greets.
You can implement an interface on your ViewHolder, then you pass an implementation of this interface to your adapter from your activity. In your adapter your pass the implementation when you create the CustomViewHolder instance (create method).
In your activity/fragment:
private val adapter = YourAdapter(object: CustomViewHolder.Listener {
fun onClick() {
// change the fragment here with the fragment manager of your activity/fragment.
}
})
In your adapter:
class YourAdapter(private val listener: CustomViewHolder.Listener): RecyclerView.Adapter {
...
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
return CustomViewHolder(
LayoutInflater.from(context).inflate(R.layout.view_layout, parent, false),
listener
)
}
}
ViewHolder implementation:
class CustomViewHolder(view: View, private val listener: Listener): ViewHolder(view) {
...
interface Listener {
fun onClick()
}
fun onCreate(parent: View, listener: Listener): CustomViewHolder {
// inflate the view and return an instance of CustomViewHolder
}
fun onBind() {
button.setOnClickListener {
listener.onClick()
}
}
}
I didn't test this code but the logic is here. You just need to adapt it to your project.