I created a scrollView programmaticaly that contains 20 views each with an image and a text.
I have two questions :
1 - is the id assignment correct and is my setOnClickListener correct?
2 - By which method onClick can I know which view of the scrollView the user has clicked?
See my code below
private var integerList: MutableList<Int>? = mutableListOf()
private var cellNo: MutableList<String>? = mutableListOf()
private var sv_mvmtChoosed = ""
private fun showSpinner() {
/* SCROllL VIEW */
var linearLayout: LinearLayout? = null
linearLayout = findViewById(R.id.linear1)
val layoutInflater = LayoutInflater.from(this)
var randIndex = 0
for (posIndex in 0..19) {
val rand = Random()
randIndex = rand.nextInt(20)
while (integerList!!.contains(randIndex)) {
randIndex = rand.nextInt(20)
}
integerList!!.add(randIndex)
// Create the view...
val view: View = layoutInflater.inflate(R.layout.scroll_bckgrnd, linearLayout, false)
// give it an id
view.id = generateViewId()
view.setOnClickListener(this)
cellNo!!.add(view.id.toString())
println(cellNo)
//... then populate it with image and text
val iv = view.findViewById<ImageView>(R.id.iv)
iv.setImageResource(sv_photoImage[randIndex])
val tv = view.findViewById<TextView>(R.id.tv)
tv.text = sv_photoName[randIndex]
linearLayout?.addView(view)
}
// which view the user did select?
fun onClick(view: View?) {
when (view!!.id) {
??? -> doSomething
}
}
}
Any idea to get me back on track will be welcome.
Its probably better to make a new OnClickListener for every view.
view.setOnClickListener(this)
needs to be this
view.setOnClickListener {
// do something
}
or
view.setOnClickListener(createOnClickListner())
fun createOnClickListner():View.OnClickListener{
return object :View.OnClickListener{
override fun onClick(view : View) {
//do something with the view that was clicked
}
}
}
Thanks a lot avalerio.
I finally found a solution as follow :
I replaced :
// give it an id
view.id = generateViewId()
view.setOnClickListener(this)
cellNo!!.add(view.id.toString())
println(cellNo)
with :
// give it an id
view.id = posIndex
view.setOnClickListener(this)
then I did this :
// the onClickListener for my 20 images/text
override fun onClick(view: View?) {
when (view!!.id) {
// Now de position clicked on the ScrollView
in 0..19 -> didHeSucceeded(view!!.id)
}
}
And use the result:
private fun didHeSucceeded(scrllPos: Int) {
// TODO: close de scrollView, how ? :-)
spinnerChoice = nameOfTechScrollVw[scrllPos]
succes = (!allreadyChoosedArray.contains(spinnerChoice)) && (currentArray.contains(spinnerChoice
))
if (succes) {
...
...
}
It works perfectly
I am trying to use a secondary display on an android device (POS terminal).
In the activities onCreate, I have :
val mediaRouter = getSystemService(Context.MEDIA_ROUTER_SERVICE) as MediaRouter
val route = mediaRouter.getSelectedRoute(MediaRouter.ROUTE_TYPE_LIVE_VIDEO)
if (route != null) {
val display = route.presentationDisplay
if (display != null) {
val presentation = TestPresentation(this, display)
presentation.show()
}
}
which correctly checks for a presentation display. Then I have my presentation class :
class TestPresentation(context: Context, display: Display):Presentation(context, display) {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
val linearLayout = LinearLayout(context)
val params = LinearLayout.LayoutParams(MATCH_PARENT, MATCH_PARENT)
linearLayout.layoutParams = params
val composeView = ComposeView(context).apply {
layoutParams = ViewGroup.LayoutParams(MATCH_PARENT, MATCH_PARENT)
setContent {
Text(text = "Hello")
}
}
linearLayout.addView(composeView)
setContentView(linearLayout)
}
At runtime I get an exception :
java.lang.IllegalStateException: ViewTreeLifecycleOwner not set for this ComposeView. If you are adding this ComposeView to an AppCompatActivity, make sure you are using AppCompat version 1.3+. If you are adding this ComposeView to a Fragment, make sure you are using Fragment version 1.3+. For other cases, manually set owners on this view by using `ViewTreeLifecycleOwner.set()` and `ViewTreeSavedStateRegistryOwner.set()`.
How do I use ViewTreeLifecycleOwner.set() and ViewTreeSavedStateRegistryOwner.set() in this case ?
I've been searching for a solution but had no luck.
An example would be great.
I have added CameraX to my ongoing development app a while ago. I know it was in alpha but I was ready to make the change when beta or final release will be available.
So I started working on it today. I have updated from
implementation 'androidx.camera:camera-core:1.0.0-alpha04'
implementation 'androidx.camera:camera-camera2:1.0.0-alpha04'
to this:
implementation 'androidx.camera:camera-core:1.0.0-beta01'
implementation 'androidx.camera:camera-camera2:1.0.0-beta01'
implementation 'androidx.camera:camera-lifecycle:1.0.0-beta01'
My Previous Working Code (alpha-04):
class ScannerX : AppCompatActivity() {
private lateinit var context: Context
var isOtpAuthCode = true
private val immersiveFlagTimeout = 500L
private val flagsFullscreen = View.SYSTEM_UI_FLAG_LOW_PROFILE or View.SYSTEM_UI_FLAG_FULLSCREEN or View.SYSTEM_UI_FLAG_LAYOUT_STABLE or
View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY or View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION or View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
private var preview: Preview? = null
private var lensFacing = CameraX.LensFacing.BACK
private var imageAnalyzer: ImageAnalysis? = null
private lateinit var analyzerThread: HandlerThread
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_scanner_x)
context = this
btnCancel.setOnClickListener {
finish()
}
analyzerThread = if (GoogleApiAvailability.getInstance().isGooglePlayServicesAvailable(context) == ConnectionResult.SUCCESS) {
HandlerThread("BarcodeFirebaseAnalyzer").apply { start() }
} else {
HandlerThread("BarcodeZxingAnalyzer").apply { start() }
}
Dexter.withActivity(this)
.withPermissions(Manifest.permission.CAMERA)
.withListener(object : MultiplePermissionsListener {
override fun onPermissionsChecked(report: MultiplePermissionsReport?) {
textureView.post {
val metrics = DisplayMetrics().also { textureView.display.getRealMetrics(it) }
val screenAspectRatio = Rational(metrics.widthPixels, metrics.heightPixels)
val previewConfig = PreviewConfig.Builder().apply {
setLensFacing(lensFacing)
// We request aspect ratio but no resolution to let CameraX optimize our use cases
setTargetAspectRatio(screenAspectRatio)
// Set initial target rotation, we will have to call this again if rotation changes
// during the lifecycle of this use case
setTargetRotation(textureView.display.rotation)
}.build()
val analyzerConfig = ImageAnalysisConfig.Builder().apply {
setLensFacing(lensFacing)
// Use a worker thread for image analysis to prevent preview glitches
setCallbackHandler(Handler(analyzerThread.looper))
// In our analysis, we care more about the latest image than analyzing *every* image
setImageReaderMode(ImageAnalysis.ImageReaderMode.ACQUIRE_LATEST_IMAGE)
// Set initial target rotation, we will have to call this again if rotation changes
// during the lifecycle of this use case
setTargetRotation(textureView.display.rotation)
}.build()
preview = AutoFitPreviewBuilder.build(previewConfig, textureView)
imageAnalyzer = ImageAnalysis(analyzerConfig).apply {
analyzer = if (GoogleApiAvailability.getInstance().isGooglePlayServicesAvailable(context) == ConnectionResult.SUCCESS) {
BarcodeFirebaseAnalyzer { qrCode ->
if (isOtpAuthCode) {
if (qrCode.startsWith("otpauth")) {
toAddAuth(qrCode)
}
} else {
toAddAuth(qrCode)
}
}
} else {
BarcodeZxingAnalyzer { qrCode ->
if (isOtpAuthCode) {
if (qrCode.startsWith("otpauth")) {
toAddAuth(qrCode)
}
} else {
toAddAuth(qrCode)
}
}
}
}
// Apply declared configs to CameraX using the same lifecycle owner
CameraX.bindToLifecycle(this#ScannerX, preview, imageAnalyzer)
}
}
override fun onPermissionRationaleShouldBeShown(permissions: MutableList<PermissionRequest>?, token: PermissionToken?) {
//
}
}).check()
}
override fun onStart() {
super.onStart()
// Before setting full screen flags, we must wait a bit to let UI settle; otherwise, we may
// be trying to set app to immersive mode before it's ready and the flags do not stick
textureView.postDelayed({
textureView.systemUiVisibility = flagsFullscreen
}, immersiveFlagTimeout)
}
override fun onDestroy() {
analyzerThread.quit()
super.onDestroy()
}
private fun toAddAuth(scannedCode: String) {
if (CameraX.isBound(imageAnalyzer)) {
CameraX.unbind(imageAnalyzer)
}
val intent = Intent()
intent.putExtra("scanResult", scannedCode)
setResult(RESULT_OK, intent)
finish()
}
companion object {
private const val RESULT_OK = 666
}
}
And the code I have changed is as follows (beta-01):
class ScannerX : AppCompatActivity() {
private lateinit var context: Context
var isOtpAuthCode = true
private val immersiveFlagTimeout = 500L
private val flagsFullscreen = View.SYSTEM_UI_FLAG_LOW_PROFILE or View.SYSTEM_UI_FLAG_FULLSCREEN or View.SYSTEM_UI_FLAG_LAYOUT_STABLE or
View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY or View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION or View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
private var preview: Preview? = null
private var lensFacing = CameraSelector.DEFAULT_BACK_CAMERA
private var imageAnalyzer: ImageAnalysis? = null
private lateinit var analysisExecutor: ExecutorService
private lateinit var processCameraProvider: ListenableFuture<ProcessCameraProvider>
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_scanner_x)
context = this
btnCancel.setOnClickListener {
finish()
}
Dexter.withActivity(this)
.withPermissions(Manifest.permission.CAMERA)
.withListener(object : MultiplePermissionsListener {
override fun onPermissionsChecked(report: MultiplePermissionsReport?) {
textureView.post {
analysisExecutor = Executors.newSingleThreadExecutor()
processCameraProvider = ProcessCameraProvider.getInstance(context)
preview = Preview.Builder()
.setTargetAspectRatio(AspectRatio.RATIO_16_9)
.setTargetRotation(textureView.display.rotation)
.build()
imageAnalyzer = ImageAnalysis.Builder()
.setBackpressureStrategy(ImageAnalysis.STRATEGY_KEEP_ONLY_LATEST)
.setTargetRotation(textureView.display.rotation)
.build()
if (GoogleApiAvailability.getInstance().isGooglePlayServicesAvailable(context) == ConnectionResult.SUCCESS) {
imageAnalyzer?.apply {
setAnalyzer(analysisExecutor, BarcodeFirebaseAnalyzer { qrCode ->
if (isOtpAuthCode) {
if (qrCode.startsWith("otpauth")) {
toAddAuth(qrCode)
}
} else {
toAddAuth(qrCode)
}
})
}
} else {
imageAnalyzer?.apply {
setAnalyzer(analysisExecutor, BarcodeZxingAnalyzer { qrCode ->
if (isOtpAuthCode) {
if (qrCode.startsWith("otpauth")) {
toAddAuth(qrCode)
}
} else {
toAddAuth(qrCode)
}
})
}
}
processCameraProvider.get().bindToLifecycle(this#ScannerX, lensFacing, imageAnalyzer)
}
}
override fun onPermissionRationaleShouldBeShown(permissions: MutableList<PermissionRequest>?, token: PermissionToken?) {
//
}
}).check()
}
override fun onStart() {
super.onStart()
// Before setting full screen flags, we must wait a bit to let UI settle; otherwise, we may
// be trying to set app to immersive mode before it's ready and the flags do not stick
textureView.postDelayed({
textureView.systemUiVisibility = flagsFullscreen
}, immersiveFlagTimeout)
}
override fun onDestroy() {
if (!analysisExecutor.isShutdown) {
analysisExecutor.shutdown()
}
super.onDestroy()
}
private fun toAddAuth(scannedCode: String) {
/*if (CameraX.isBound(imageAnalyzer)) {
CameraX.unbind(imageAnalyzer)
}*/
val intent = Intent()
intent.putExtra("scanResult", scannedCode)
setResult(RESULT_OK, intent)
finish()
}
companion object {
private const val RESULT_OK = 666
}
}
After I upgraded there were so many changes in library and now I cant make it work.
I also cant use Google Provided AutoFitPreview Class along with initial alpha release of this library. This was not necessary even with alpha04 since the only problem without this class was camera view little bit stretched out but scanning and analyzing worked properly.
/**
* Builder for [Preview] that takes in a [WeakReference] of the view finder and [PreviewConfig],
* then instantiates a [Preview] which automatically resizes and rotates reacting to config changes.
*/
class AutoFitPreviewBuilder private constructor(config: PreviewConfig, viewFinderRef: WeakReference<TextureView>) {
/** Public instance of preview use-case which can be used by consumers of this adapter */
val useCase: Preview
/** Internal variable used to keep track of the use case's output rotation */
private var bufferRotation: Int = 0
/** Internal variable used to keep track of the view's rotation */
private var viewFinderRotation: Int? = null
/** Internal variable used to keep track of the use-case's output dimension */
private var bufferDimens: Size = Size(0, 0)
/** Internal variable used to keep track of the view's dimension */
private var viewFinderDimens: Size = Size(0, 0)
/** Internal variable used to keep track of the view's display */
private var viewFinderDisplay: Int = -1
/** Internal reference of the [DisplayManager] */
private lateinit var displayManager: DisplayManager
/**
* We need a display listener for orientation changes that do not trigger a configuration
* change, for example if we choose to override config change in manifest or for 180-degree
* orientation changes.
*/
private val displayListener = object : DisplayManager.DisplayListener {
override fun onDisplayAdded(displayId: Int) = Unit
override fun onDisplayRemoved(displayId: Int) = Unit
override fun onDisplayChanged(displayId: Int) {
val viewFinder = viewFinderRef.get() ?: return
if (displayId == viewFinderDisplay) {
val display = displayManager.getDisplay(displayId)
val rotation = getDisplaySurfaceRotation(display)
updateTransform(viewFinder, rotation, bufferDimens, viewFinderDimens)
}
}
}
init {
// Make sure that the view finder reference is valid
val viewFinder = viewFinderRef.get() ?:
throw IllegalArgumentException("Invalid reference to view finder used")
// Initialize the display and rotation from texture view information
viewFinderDisplay = viewFinder.display.displayId
viewFinderRotation = getDisplaySurfaceRotation(viewFinder.display) ?: 0
// Initialize public use-case with the given config
useCase = Preview(config)
// Every time the view finder is updated, recompute layout
useCase.onPreviewOutputUpdateListener = Preview.OnPreviewOutputUpdateListener {
val viewFinderI = viewFinderRef.get() ?: return#OnPreviewOutputUpdateListener
Log.d(TAG, "Preview output changed. " +
"Size: ${it.textureSize}. Rotation: ${it.rotationDegrees}")
// To update the SurfaceTexture, we have to remove it and re-add it
val parent = viewFinderI.parent as ViewGroup
parent.removeView(viewFinderI)
parent.addView(viewFinderI, 0)
// Update internal texture
viewFinderI.surfaceTexture = it.surfaceTexture
// Apply relevant transformations
bufferRotation = it.rotationDegrees
val rotation = getDisplaySurfaceRotation(viewFinderI.display)
updateTransform(viewFinderI, rotation, it.textureSize, viewFinderDimens)
}
// Every time the provided texture view changes, recompute layout
viewFinder.addOnLayoutChangeListener { view, left, top, right, bottom, _, _, _, _ ->
val viewFinderII = view as TextureView
val newViewFinderDimens = Size(right - left, bottom - top)
Log.d(TAG, "View finder layout changed. Size: $newViewFinderDimens")
val rotation = getDisplaySurfaceRotation(viewFinderII.display)
updateTransform(viewFinderII, rotation, bufferDimens, newViewFinderDimens)
}
// Every time the orientation of device changes, recompute layout
// NOTE: This is unnecessary if we listen to display orientation changes in the camera
// fragment and call [Preview.setTargetRotation()] (like we do in this sample), which will
// trigger [Preview.OnPreviewOutputUpdateListener] with a new
// [PreviewOutput.rotationDegrees]. CameraX Preview use case will not rotate the frames for
// us, it will just tell us about the buffer rotation with respect to sensor orientation.
// In this sample, we ignore the buffer rotation and instead look at the view finder's
// rotation every time [updateTransform] is called, which gets triggered by
// [CameraFragment] display listener -- but the approach taken in this sample is not the
// only valid one.
displayManager = viewFinder.context
.getSystemService(Context.DISPLAY_SERVICE) as DisplayManager
displayManager.registerDisplayListener(displayListener, null)
// Remove the display listeners when the view is detached to avoid holding a reference to
// it outside of the Fragment that owns the view.
// NOTE: Even though using a weak reference should take care of this, we still try to avoid
// unnecessary calls to the listener this way.
viewFinder.addOnAttachStateChangeListener(object : View.OnAttachStateChangeListener {
override fun onViewAttachedToWindow(view: View?) =
displayManager.registerDisplayListener(displayListener, null)
override fun onViewDetachedFromWindow(view: View?) =
displayManager.unregisterDisplayListener(displayListener)
})
}
/** Helper function that fits a camera preview into the given [TextureView] */
private fun updateTransform(textureView: TextureView?, rotation: Int?, newBufferDimens: Size, newViewFinderDimens: Size) {
// This should not happen anyway, but now the linter knows
val textureViewI = textureView ?: return
if (rotation == viewFinderRotation &&
Objects.equals(newBufferDimens, bufferDimens) &&
Objects.equals(newViewFinderDimens, viewFinderDimens)) {
// Nothing has changed, no need to transform output again
return
}
if (rotation == null) {
// Invalid rotation - wait for valid inputs before setting matrix
return
} else {
// Update internal field with new inputs
viewFinderRotation = rotation
}
if (newBufferDimens.width == 0 || newBufferDimens.height == 0) {
// Invalid buffer dimens - wait for valid inputs before setting matrix
return
} else {
// Update internal field with new inputs
bufferDimens = newBufferDimens
}
if (newViewFinderDimens.width == 0 || newViewFinderDimens.height == 0) {
// Invalid view finder dimens - wait for valid inputs before setting matrix
return
} else {
// Update internal field with new inputs
viewFinderDimens = newViewFinderDimens
}
val matrix = Matrix()
Log.d(TAG, "Applying output transformation.\n" +
"View finder size: $viewFinderDimens.\n" +
"Preview output size: $bufferDimens\n" +
"View finder rotation: $viewFinderRotation\n" +
"Preview output rotation: $bufferRotation")
// Compute the center of the view finder
val centerX = viewFinderDimens.width / 2f
val centerY = viewFinderDimens.height / 2f
// Correct preview output to account for display rotation
matrix.postRotate(-viewFinderRotation!!.toFloat(), centerX, centerY)
// Buffers are rotated relative to the device's 'natural' orientation: swap width and height
val bufferRatio = bufferDimens.height / bufferDimens.width.toFloat()
val scaledWidth: Int
val scaledHeight: Int
// Match longest sides together -- i.e. apply center-crop transformation
if (viewFinderDimens.width > viewFinderDimens.height) {
scaledHeight = viewFinderDimens.width
scaledWidth = (viewFinderDimens.width * bufferRatio).roundToInt()
} else {
scaledHeight = viewFinderDimens.height
scaledWidth = (viewFinderDimens.height * bufferRatio).roundToInt()
}
// Compute the relative scale value
val xScale = scaledWidth / viewFinderDimens.width.toFloat()
val yScale = scaledHeight / viewFinderDimens.height.toFloat()
// Scale input buffers to fill the view finder
matrix.preScale(xScale, yScale, centerX, centerY)
// Finally, apply transformations to our TextureView
textureViewI.setTransform(matrix)
}
companion object {
private val TAG = AutoFitPreviewBuilder::class.java.simpleName
/** Helper function that gets the rotation of a [Display] in degrees */
fun getDisplaySurfaceRotation(display: Display?) = when(display?.rotation) {
Surface.ROTATION_0 -> 0
Surface.ROTATION_90 -> 90
Surface.ROTATION_180 -> 180
Surface.ROTATION_270 -> 270
else -> null
}
/**
* Main entry point for users of this class: instantiates the adapter and returns an instance
* of [Preview] which automatically adjusts in size and rotation to compensate for
* config changes.
*/
fun build(config: PreviewConfig, viewFinder: TextureView) =
AutoFitPreviewBuilder(config, WeakReference(viewFinder)).useCase
}
}
Please Help
I have listView with ringtones
I need change play_arrow image to stop image every time when music started or stoped.
When I click play on one image it become stop image and then I click play on other music item image so previous should become play_arrow and just clicked one should become stop.
The problem is on getting views by position. Everything works great on first 12 music views. And if I try to get view like this parent.getChildAt(previousListened) with previousListened > 12 it returns null.
EDIT: add adapter class
class SoundListAdapter constructor(
private var context: Context,
private val layout: Int,
private var arrayList: ArrayList<Sound>,
private val activity: FragmentActivity,
private val mediaPlayer: MediaPlayer
) : BaseAdapter() {
private var selectedPosition = -1
private var currentListened = -1
private var previousListened = -1
private var isPlaying = false
private var TAG = "SoundListAdapter"
private val mSendSoundUri: SendSoundUri = activity as SendSoundUri
interface SendSoundUri {
fun sendSoundUri(input: String?)
}
override fun getCount(): Int {
return arrayList.size
}
override fun getItem(i: Int): Any {
return ""
}
override fun getItemId(i: Int): Long {
return i.toLong()
}
private inner class ViewHolder {
internal var radioButton: RadioButton? = null
internal var txtName: TextView? = null
internal var ivPlay: ImageView? = null
}
override fun getView(position: Int, convertView: View?, parent: ViewGroup): View {
var convertView = convertView
val viewHolder: ViewHolder
if (convertView == null) {
viewHolder = ViewHolder()
val layoutInflater = context.getSystemService(LAYOUT_INFLATER_SERVICE) as LayoutInflater
convertView = layoutInflater.inflate(layout, null)
viewHolder.txtName = convertView!!.findViewById(R.id.sound_name)
viewHolder.radioButton = convertView.findViewById(R.id.sound_radiobutton)
viewHolder.ivPlay = convertView.findViewById(R.id.ivPlay) as ImageView
convertView.tag = viewHolder
} else {
viewHolder = convertView.tag as ViewHolder
}
//check the radio button if both position and selectedPosition matches
viewHolder.radioButton?.isChecked = (position === selectedPosition)
// TODO add color to checked circle
//Set the position tag to both radio button and label
viewHolder.radioButton?.tag = position
viewHolder.ivPlay?.tag = position
viewHolder.txtName?.tag = position
viewHolder.radioButton?.setOnClickListener { v -> itemCheckChanged(v) }
viewHolder.txtName?.setOnClickListener { v -> itemCheckChanged(v) }
val music = arrayList[position]
viewHolder.txtName!!.text = music.title
// play music
viewHolder.ivPlay!!.setOnClickListener {
previousListened = currentListened
currentListened = it.tag as Int
// TODO add black square when playing
Log.d(TAG, "max items: ${parent.childCount}")
Log.d(TAG, "previousListened: $previousListened")
if (previousListened != -1 && previousListened == currentListened && mediaPlayer.isPlaying) {
mediaPlayer.stop()
} else {
mediaPlayer.reset()
mediaPlayer.setDataSource(context, Uri.parse(music.uri))
mediaPlayer.prepare()
mediaPlayer.start()
}
}
return convertView
}
private fun getSelectedSound(): Sound? {
Log.d(TAG, "sending selectedPosition: $selectedPosition")
if (selectedPosition == -1)
return null
return arrayList[selectedPosition]
}
private fun itemCheckChanged(v: View) {
selectedPosition = v.tag as Int
mSendSoundUri.sendSoundUri(getSelectedSound()?.uri)
Log.d(TAG, "selectedPosition changed to: $selectedPosition")
notifyDataSetChanged()
}
}
Is it possible to get item view of ListView that is outside of visible part in Adapter class?
Is it possible to get item view of ListView that is outside of visible part in Adapter class?
No, you can't. ViewHolder exists only for visible items.
However, in your case, you only need to set your ImageView image inside your getView function.
if (currentListened == position) {
// set here your Stop image
viewHolder.ivPlay.setImageResource(R.drawable.stop);
} else {
// set here your Play image
viewHolder.ivPlay.setImageResource(R.drawable.play);
}
Then, call notifyDataSetChanged
viewHolder.ivPlay!!.setOnClickListener {
...
...
notifyDataSetChanged();
}
notifyDataSetChange will update all visible items.
On the other hand, you don't need to save position in tag variable. You always know which item is clicked because your onClick events are set in getView function.
https://youtu.be/n8MdHNYozgs
I implemented shared element transition between fragment and activity like on the video above
val intent = Intent(context, Main2Activity::class.java)
val list = ArrayList<Pair<View, String>>()
(recyclerView.adapter as Adapter).list.forEachIndexed { index, entity ->
val itemView = recyclerView.findViewHolderForAdapterPosition(index)?.itemView
if (itemView != null) {
list.add(Pair(itemView, entity.id.toString()))
}
}
val options = ActivityOptionsCompat.makeSceneTransitionAnimation(activity, *list.toTypedArray())
startActivity(intent, options.toBundle())
And in the activity I display views in another recycler view.
Could you please give me an advice what I should do to avoid blinking at the end of scaling down images?
I found the solution. The thing is I used itemView as view for transition:
val itemView = recyclerView.findViewHolderForAdapterPosition(index)?.itemView
if (itemView != null) {
list.add(Pair(itemView, entity.id.toString()))
}
But need to use the following code:
val holder = MyRecyclerView.findViewHolderForAdapterPosition(index)
if (holder != null) {
with(holder as MyViewHolder) {
list.add(Pair(this.image, entity.id.toString()))
}
}
And everything works fine.