Convert java to kotlin breaks contextmenu - java

I've been converting a project to Kotlin and discovered a problem. The context menu from the java code is broken in the generated kotlin.This is a simplified test of the source from the project. It consists of only a main activity with a single layout and a context menu. The java version works but the kotlin version crashes. The only thing I can think of that is unusual is that the view I'm registering is an imageView in a RelativeLayout.
java.lang.NullPointerException:
Parameter specified as non-null is null:
method kotlin.jvm.internal.Intrinsics.checkNotNullParameter
, parameter menuInfo
at com...MainActivity.onCreateContextMenu(MainActivity.kt)
at android.view.View.createContextMenu(View.java:8392)
at com.android.internal.view.menu.ContextMenuBuilder
.show(ContextMenuBuilder.java:81)
at com.android.internal.policy.impl
.PhoneWindow$DecorView
.showContextMenuForChild(PhoneWindow.java:2517)
at android.view.ViewGroup.showContextMenuForChild(ViewGroup.java:658)
MainActivity.java is:
public class MainActivity extends AppCompatActivity {
private static int animationSpeed = 0;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
registerForContextMenu(findViewById(R.id.imageView));
}
#Override
public void onCreateContextMenu(ContextMenu menu, View v,
ContextMenu.ContextMenuInfo menuInfo) {
super.onCreateContextMenu(menu, v, menuInfo);
MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.speed_select, menu);
menu.getItem(animationSpeed).setChecked(true);
}
#Override
public boolean onContextItemSelected(MenuItem item) {
int itemId = item.getItemId();
boolean rv = true;
switch(itemId) {
case R.id.animate_slow: animationSpeed = 0; break;
case R.id.animate_normal: animationSpeed = 1; break;
case R.id.animate_fast: animationSpeed = 2; break;
default: Log.d("onContextItemSelected", String.format(
"menu item unhandled:0x%08x", itemId)
);
rv = false;
}
return rv;
}
}
MainActivity.kt is:
class MainActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
registerForContextMenu(findViewById(R.id.imageView))
}
override fun onCreateContextMenu(menu: ContextMenu, v: View,
menuInfo: ContextMenuInfo) {
super.onCreateContextMenu(menu, v, menuInfo)
val inflater = menuInflater
inflater.inflate(R.menu.speed_select, menu)
menu.getItem(animationSpeed).isChecked = true
}
override fun onContextItemSelected(item: MenuItem): Boolean {
val itemId = item.itemId
var rv = true
when (itemId) {
R.id.animate_slow -> animationSpeed = 0
R.id.animate_normal -> animationSpeed = 1
R.id.animate_fast -> animationSpeed = 2
else -> {
Log.d("onContextItemSelected", String.format(
"menu item unhandled:0x%08x", itemId))
rv = false
}
}
return rv
}
companion object {
private var animationSpeed = 0
}
}
My menu file is:
<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android" >
<group
android:checkableBehavior="single"
android:id="#+id/animate_speed" >
<item android:id="#+id/animate_slow"
android:title="#string/slow" />
<item android:id="#+id/animate_normal"
android:title="#string/normal" />
<item android:id="#+id/animate_fast"
android:title="#string/fast" />
</group>
</menu>
The activity layout is:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/relative_layout"
android:layout_width="match_parent"
android:layout_height="match_parent">
<ImageView
android:id="#+id/imageView"
android:layout_width="250dp"
android:layout_height="250dp"
android:layout_centerInParent="true"
android:background="#drawable/andy"
/>
</RelativeLayout>
I've tried breaking in the onCreateContextMenu but never get there.
I'm using Kotlin 1.40, AndroidStudio 4.01, SDK 30, and gradle 4.01. I've been looking at the docs and the code for a couple of days now and to me, the generated kotlin looks right.Thanks!
Thanks to John Healy below this was solved.
John said he thought it might be in Kotlin's null-safety handling. I doubted so I added a log statement to the working Java code and menuInfo was coming in as a null. I added a #Nullable annotation to the Java declaration which gave me:
public void onCreateContextMenu(
ContextMenu menu, View v,
#Nullable ContextMenu.ContextMenuInfo menuInfo)
Testing of the Java code showed the compiler and lint were happy and the code still ran. I again ran the jave through the conversion process and the resulting kotlin signature for the function is:
override fun onCreateContextMenu(
menu: ContextMenu, v: View,
menuInfo: ContextMenuInfo?)
I tested the Kotlin and it now works too!
NOTE: for your edification and amusement I posted the source on
git hub.

I'm only puting up this reply to my question so people will notice a solution was found thanks to a commentor. This fix only applies if you are using a menu list rather than creating individual menu items and the fix is only necessary for Kotlin because of the way in which Kotlin handles null-safety. Please look at the end of the question and at my comment to that question,
Steve S.

Related

Drag and drop ImageView into a container for verification

To understand it better read this :
First game :
Skate QuestionMark
Archery QuestionMark
Swim QuestionMark
---------------------------
Water Bow Wheel
If user drags Water to Skate or Archery QuestionMark it will animate to the list (because it is not correct)
If user drags twice incorrect (it will mark the one that is correct from the answer list)
If user still fail in the third try it will drag to the incorrect one and then it will highlight or just change the color doesn't matter to red.
If user drags to the correct one it will highlight green and replace QuestionMark with the correct one (I do not want to be draggable anymore that image)
------
Game 2 (is more or less the same...)
There's no QuestionMark column, there's only :
Skate
Swim
Archery
--------------
(Lot of answers)
Now the way to play is the same (about the fails and etc) the thing is now when I drag any answer to the correct one it won't replace the correct one, it will just disappear and if it fails instead of highlighting all the corrects one it will highlight the correct answer (for instance; if I drag wheel to Swim once, it doesn't happen anything just animate to the place where it was, if I do it twice it will highlight the Skate one, and if it fails at third one it just drag wherever he did and highlight with red)
I'm planning to build an app that does a simple check, I'm calling an endpoint and I'll get some params, and then I'll know how many ImageView are going to be displayed in the screen.
This is like a puzzle, and it would look like this :
So I have different options, which contains only one correct answer, I'm planing the way to achieve this, could be able to drag "Bow" to the questionmark infront of "skateboarding" and then says that is not correct, then drag it to the "archery" one and replace the questionmark for the ImageView from the bottom that contains the word "Arrow".
Layout should contain one column for Question (this should be the sports) then another one in front of the Question one and should be the Answer one, then below them should contain the Options one.
Was it clear? Otherwise let me know and I'll try to explain it a little bit with more details.
EDIT
What I thought is having like a class that contains a list of Answers or just create like :
RightList : (id:1,id:2,id:3)
LeftList : (id:1, id:2, id:3)
DownList : (Bow = id:2),(Skate = id:1), (Ball = id:3)
Then doing the drag and drop thing when the DragEvent.ACTION_DROP or DragEvent.ACTION_DRAG_ENDEDI do not know which one, check (Pseudocode below)
if(imageDragged.id==location.id) then replace the question mark image for imageDragged
else animate the image to the place where it comes
I do not know if creating a class that implements onDragListener() or something like that, I'd like to have it generic so I can use it on different games like for instance :
SKATE(id:1) ARCHERY(id:2) FOOTBALL(id:3)
Answers : TABLE(C.A. id:1) BOW(C.A. id:2) GRASS(C.A. id:3) GOAL(C.A. id:3) BALL(C.A. id:3) ARROW(C.A. id:2) AXES(C.A. id:1) WHEELS(C.A. id:1)
So if I drag and drop for instance BOW to FOOTBALL then it should display that is bad, otherwise say that it's good.
EXAMPLE 1/3
Just for reference and summarize everything. Here is one 100 lines code, within single Activity and imports, representing all this behavior even with simple animation.
class MainActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
bind()
}
private fun bind() {
addQuestions()
addAnswers()
}
#SuppressLint("InflateParams")
private fun addQuestions() {
val inflater = getSystemService(
Context.LAYOUT_INFLATER_SERVICE
) as LayoutInflater
for (i in 1..8) {
val view = inflater.inflate(R.layout.item_question, null)
view.setOnDragListener(DragListener())
questionContainer.addView(view)
}
}
#SuppressLint("InflateParams")
private fun addAnswers() {
val inflater = getSystemService(
Context.LAYOUT_INFLATER_SERVICE
) as LayoutInflater
for (i in 1..8) {
val view = inflater.inflate(R.layout.item_answer, null)
view.setOnTouchListener(DragItemTouchListener())
answerContainer.addView(view)
}
}
private inner class DragItemTouchListener : OnTouchListener {
override fun onTouch(view: View, motionEvent: MotionEvent): Boolean {
return if (motionEvent.action == MotionEvent.ACTION_DOWN) {
dragMultiple(view)
true
} else {
false
}
}
private fun dragMultiple(view : View) {
val data = ClipData.newPlainText("", "")
val shadowBuilder = DragShadowBuilder(
view
)
val parent = view.parent as ViewGroup
view.startDragAndDrop(data, shadowBuilder, view, 0)
parent.removeView(view)
}
}
private inner class DragListener : OnDragListener {
override fun onDrag(v: View, event: DragEvent): Boolean {
when (event.action) {
DragEvent.ACTION_DRAG_STARTED -> {
}
DragEvent.ACTION_DRAG_ENTERED -> {
}
DragEvent.ACTION_DRAG_EXITED -> {
}
DragEvent.ACTION_DROP -> {
animateDropEffect(v as ViewGroup, event.localState as View)
}
DragEvent.ACTION_DRAG_ENDED -> {
}
else -> {
}
}
return true
}
private fun animateDropEffect(into: ViewGroup, view: View) {
into.addView(view)
val params = (view.layoutParams as FrameLayout.LayoutParams)
.apply {
gravity = Gravity.END
}
view.layoutParams = params
}
}
}
All Xmls used. Below xml for all examples below.
/* activity_main.xml */
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout
android:id="#+id/mainContainer"
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">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context=".MainActivity">
<ScrollView
android:layout_width="match_parent"
android:layout_height="500dp"
android:animateLayoutChanges="true">
<LinearLayout
android:id="#+id/questionContainer"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:animateLayoutChanges="true"
android:orientation="vertical">
</LinearLayout>
</ScrollView>
<HorizontalScrollView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:animateLayoutChanges="true">
<LinearLayout
android:id="#+id/answerContainer"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:animateLayoutChanges="true"
android:orientation="horizontal">
</LinearLayout>
</HorizontalScrollView>
</LinearLayout>
</FrameLayout>
/* item_question.xml */
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:animateLayoutChanges="true"
android:padding="5dp">
<View
android:layout_width="100dp"
android:layout_height="100dp"
android:layout_gravity="start"
android:background="#android:color/holo_blue_bright">
</View>
<View
android:id="#+id/questionView"
android:layout_width="100dp"
android:layout_height="100dp"
android:layout_gravity="end"
android:background="#android:color/holo_orange_light">
</View>
</FrameLayout>
/* item_answer.xml */
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical"
android:padding="5dp"
android:tag="Test">
<LinearLayout
android:layout_width="100dp"
android:layout_height="100dp"
android:layout_gravity="center"
android:background="#android:color/darker_gray">
</LinearLayout>
</FrameLayout>
EXAMPLE 2/3
It's not a problem to make dragging for few elements following with a the same approach. Here is a little crappy, but simple example.
Modified code for second example. Xml stay the same.
class MainActivity : AppCompatActivity() {
var activeOneDrag : Boolean = false
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
bind()
}
private fun bind() {
addQuestions()
addAnswers()
}
fun getRandomColor(): Int {
return Color.argb(255, Random.nextInt(255),
Random.nextInt(255), Random.nextInt(255))
}
#SuppressLint("InflateParams")
private fun addQuestions() {
val inflater = getSystemService(
Context.LAYOUT_INFLATER_SERVICE
) as LayoutInflater
for (i in 1..8) {
val view = inflater.inflate(R.layout.item_question, null)
view.setOnDragListener(DragListener())
questionContainer.addView(view)
}
}
#SuppressLint("InflateParams")
private fun addAnswers() {
val inflater = getSystemService(
Context.LAYOUT_INFLATER_SERVICE
) as LayoutInflater
for (i in 1..8) {
val view = inflater.inflate(R.layout.item_answer, null)
(view as ViewGroup).getChildAt(0).setBackgroundColor(getRandomColor())
view.setOnTouchListener(DragItemTouchListener())
answerContainer.addView(view)
}
}
private inner class DragItemTouchListener : OnTouchListener {
override fun onTouch(view: View, motionEvent: MotionEvent): Boolean {
return if (motionEvent.action == MotionEvent.ACTION_DOWN) {
dragMultiple(view)
true
} else {
false
}
}
private fun dragMultiple(view : View) {
val parent = view.parent as ViewGroup
parent.removeView(view)
/**
* Some other logic with selective multiple View.
* Just getting neighbor in our case
*/
var anotherView : View? = null
if (!activeOneDrag) {
anotherView = parent.getChildAt(
parent.indexOfChild(view) + 1)
parent.removeView(anotherView)
}
activeOneDrag = !activeOneDrag
/**
* As you can see, there is postDelay here.
* But only for our case with animateLayoutChanges,
* with delays removing View! In your samples, you could remove it
* with listener on your own animation, if any!
*/
parent.postDelayed({
val layout = LinearLayout(this#MainActivity)
val params = FrameLayout.LayoutParams(
FrameLayout.LayoutParams.WRAP_CONTENT,
FrameLayout.LayoutParams.WRAP_CONTENT)
params.gravity = Gravity.BOTTOM
layout.layoutParams = params
layout.orientation = LinearLayout.HORIZONTAL
layout.addView(view)
if (anotherView != null) {
layout.addView(anotherView)
}
layout.visibility = INVISIBLE
mainContainer.addView(layout)
parent.post {
layout.startDragAndDrop(
ClipData.newPlainText("", ""),
DragShadowBuilder(layout), layout, 0)
}
}, 400)
}
}
private inner class DragListener : OnDragListener {
override fun onDrag(v: View, event: DragEvent): Boolean {
when (event.action) {
DragEvent.ACTION_DRAG_STARTED -> {
}
DragEvent.ACTION_DRAG_ENTERED -> {
}
DragEvent.ACTION_DRAG_EXITED -> {
}
DragEvent.ACTION_DROP -> {
val view = event.localState as View
(view.parent as ViewGroup).removeView(view)
view.visibility = VISIBLE
animateDropEffect(v as ViewGroup, event.localState as View)
}
DragEvent.ACTION_DRAG_ENDED -> {
}
else -> {
}
}
return true
}
private fun animateDropEffect(into: ViewGroup, view: View) {
into.addView(view)
val params = (view.layoutParams as FrameLayout.LayoutParams)
.apply {
gravity = Gravity.END
}
view.layoutParams = params
}
}
}
EXAMPLE 3/3
As I see, it's not clear, how to change simple actions with animation or Drag listening area. Here is another simple example of doing all actions
class MainActivity : AppCompatActivity() {
#Volatile
var state : State = State.INACTIVE
enum class State {
ACTIVE, INACTIVE, HANDLED
}
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
bind()
}
private fun bind() {
addQuestions()
addAnswers()
}
private fun getRandomColor(): Int {
return Color.argb(255, Random.nextInt(255),
Random.nextInt(255), Random.nextInt(255))
}
#SuppressLint("InflateParams")
private fun addQuestions() {
val inflater = getSystemService(
Context.LAYOUT_INFLATER_SERVICE
) as LayoutInflater
for (i in 1..8) {
val view = inflater.inflate(R.layout.item_question, null)
view.findViewById<View>(R.id.questionView)
.setOnDragListener(DragListener())
questionContainer.addView(view)
}
}
#SuppressLint("InflateParams")
private fun addAnswers() {
val inflater = getSystemService(
Context.LAYOUT_INFLATER_SERVICE
) as LayoutInflater
for (i in 1..8) {
val view = inflater.inflate(R.layout.item_answer, null)
(view as ViewGroup).getChildAt(0).setBackgroundColor(getRandomColor())
view.setOnTouchListener(DragItemTouchListener())
answerContainer.addView(view)
}
}
private inner class DragItemTouchListener : OnTouchListener {
val ITEM_INDEX_D = "Index-From"
override fun onTouch(view: View, motionEvent: MotionEvent): Boolean {
return if (motionEvent.action == MotionEvent.ACTION_DOWN) {
createDrag(view)
true
} else {
false
}
}
private fun createDrag(view : View) {
val parent = view.parent as ViewGroup
view.tag = Pair(ITEM_INDEX_D,
parent.indexOfChild(view))
view.startDragAndDrop(ClipData.newPlainText("", ""),
DragShadowBuilder(view), view, 0)
parent.removeView(view)
parent.setBackgroundColor(Color.WHITE)
}
}
private inner class DragListener : OnDragListener {
override fun onDrag(parent: View, event: DragEvent): Boolean {
val view = event.localState as View
when (event.action) {
DragEvent.ACTION_DRAG_STARTED -> {
state = State.ACTIVE
}
DragEvent.ACTION_DRAG_ENTERED -> {
}
DragEvent.ACTION_DRAG_EXITED -> {
}
DragEvent.ACTION_DROP -> {
state = State.HANDLED
animateDropEffect(parent, view)
return true
}
DragEvent.ACTION_DRAG_ENDED -> {
if (state == State.ACTIVE) {
state = State.INACTIVE
animateMoveBack(view,
(view.tag as Pair<*, *>).second as Int)
}
return true
}
else -> {
}
}
return true
}
private fun animateMoveBack(view: View, index : Int) {
answerContainer.addView(view, index)
}
private fun animateDropEffect(into: View, view: View) {
val parent = (into.parent as ViewGroup)
parent.addView(view)
val params = (view.layoutParams as FrameLayout.LayoutParams)
.apply {
gravity = Gravity.END
}
view.layoutParams = params
checkIsCorrect(parent)
}
private fun checkIsCorrect(parent : ViewGroup) {
val correct = Random.nextBoolean()
val colorFrom = Color.WHITE
val colorTo : Int = if (correct) 0x8000ff00.toInt() else 0x80ff0000.toInt()
ObjectAnimator.ofObject(
parent,
"backgroundColor",
ArgbEvaluator(),
colorFrom,
colorTo
)
.setDuration(1000)
.start()
}
}
}
UPDATE
The last update from the comments sections. I think it's enough, and of course you would need you changes. So just change two "if" statement to align with your requirements and animation.
class MainActivity : AppCompatActivity() {
enum class State {
ACTIVE, INACTIVE, HANDLED
}
var state : State = State.INACTIVE
var failsCount = 0
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
bind()
}
private fun bind() {
addQuestions()
addAnswers()
}
private fun getRandomColor(): Int {
return Color.argb(255, Random.nextInt(255),
Random.nextInt(255), Random.nextInt(255))
}
#SuppressLint("InflateParams")
private fun addQuestions() {
val inflater = getSystemService(
Context.LAYOUT_INFLATER_SERVICE
) as LayoutInflater
for (i in 1..3) {
val view = inflater.inflate(R.layout.item_question, null)
view.findViewById<View>(R.id.questionView)
.setOnDragListener(DragListener())
questionContainer.addView(view)
}
}
#SuppressLint("InflateParams")
private fun addAnswers() {
val inflater = getSystemService(
Context.LAYOUT_INFLATER_SERVICE
) as LayoutInflater
for (i in 1..3) {
val view = inflater.inflate(R.layout.item_answer, null)
(view as ViewGroup).getChildAt(0).setBackgroundColor(getRandomColor())
view.setOnTouchListener(DragItemTouchListener())
answerContainer.addView(view)
}
}
private inner class DragItemTouchListener : OnTouchListener {
val ITEM_INDEX_D = "Index-From"
override fun onTouch(view: View, motionEvent: MotionEvent): Boolean {
return if (motionEvent.action == MotionEvent.ACTION_DOWN) {
createDrag(view)
true
} else {
false
}
}
private fun createDrag(view : View) {
val parent = view.parent as ViewGroup
view.tag = Pair(ITEM_INDEX_D,
parent.indexOfChild(view))
view.startDragAndDrop(ClipData.newPlainText("", ""),
DragShadowBuilder(view), view, 0)
parent.removeView(view)
parent.setBackgroundColor(Color.WHITE)
}
}
private inner class DragListener : OnDragListener {
val ANIM_DURATION_LONG = TimeUnit.SECONDS.toMillis(1)
val ANIM_DURATION_SHORT = TimeUnit.MILLISECONDS.toMillis(500)
val GREEN_ALPHA = 0x8000ff00.toInt()
val RED_ALPHA = 0x80ff0000.toInt()
val ANIM_COLOR = "backgroundColor"
override fun onDrag(parent: View, event: DragEvent): Boolean {
val view = event.localState as View
when (event.action) {
DragEvent.ACTION_DRAG_STARTED -> {
state = State.ACTIVE
}
DragEvent.ACTION_DRAG_ENTERED -> {
}
DragEvent.ACTION_DRAG_EXITED -> {
}
DragEvent.ACTION_DROP -> {
state = State.HANDLED
animateDropEffect(parent, view)
return true
}
DragEvent.ACTION_DRAG_ENDED -> {
if (state == State.ACTIVE) {
state = State.INACTIVE
animateMoveBack(view,
(view.tag as Pair<*, *>).second as Int)
}
return true
}
else -> {
}
}
return true
}
private fun animateMoveBack(view: View, index : Int) {
answerContainer.addView(view, index)
}
private fun animateDropEffect(into: View, view: View) {
val parent = (into.parent as ViewGroup)
parent.addView(view)
val params = (view.layoutParams as FrameLayout.LayoutParams)
.apply {
gravity = Gravity.END
}
view.layoutParams = params
checkIsCorrect(parent)
}
private fun checkIsCorrect(parent : ViewGroup) {
val correct = false
if (correct) {
animateColorChange(parent, true)
return
}
if (++failsCount > Companion.MAX_FAIL_COUNT) {
animateColorChange(parent, false)
return
}
animateWrongAttempt(parent)
}
private fun animateWrongAttempt(parent: ViewGroup) {
val questionMark = parent.findViewById<View>(R.id.questionView)
questionMark.setBackgroundColor(Color.RED)
val va = ValueAnimator.ofFloat(1f, 1.1f)
va.interpolator = BounceInterpolator()
va.duration = ANIM_DURATION_SHORT
va.addUpdateListener { animation ->
questionMark.scaleX = animation.animatedValue as Float
questionMark.scaleY = animation.animatedValue as Float
}
va.start()
}
private fun animateColorChange(parent : ViewGroup, right : Boolean) {
val colorFrom = Color.WHITE
ObjectAnimator
.ofObject(parent, ANIM_COLOR,
ArgbEvaluator(), colorFrom,
if (right) GREEN_ALPHA else RED_ALPHA)
.setDuration(ANIM_DURATION_LONG)
.start()
}
}
companion object {
const val MAX_FAIL_COUNT = 2
}
}
And new xml.
/* activity_main.xml */
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout
android:id="#+id/mainContainer"
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">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context=".MainActivity">
<ScrollView
android:layout_width="match_parent"
android:layout_height="500dp"
android:animateLayoutChanges="true">
<LinearLayout
android:id="#+id/questionContainer"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:animateLayoutChanges="true"
android:orientation="vertical">
</LinearLayout>
</ScrollView>
<HorizontalScrollView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:animateLayoutChanges="true">
<LinearLayout
android:id="#+id/answerContainer"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:animateLayoutChanges="true"
android:orientation="horizontal">
</LinearLayout>
</HorizontalScrollView>
</LinearLayout>
</FrameLayout>
/* item_question.xml */
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:animateLayoutChanges="true"
android:paddingTop="10dp">
<View
android:layout_width="100dp"
android:layout_height="100dp"
android:layout_gravity="start"
android:layout_margin="5dp"
android:background="#android:color/holo_blue_bright">
</View>
<View
android:id="#+id/questionView"
android:layout_width="100dp"
android:layout_height="100dp"
android:layout_gravity="end"
android:layout_margin="5dp"
android:background="#android:color/holo_orange_light">
</View>
</FrameLayout>
/* item_answer.xml */
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical"
android:padding="5dp"
android:tag="Test">
<LinearLayout
android:layout_width="100dp"
android:layout_height="100dp"
android:layout_gravity="center"
android:background="#android:color/darker_gray">
</LinearLayout>
</FrameLayout>
I think, there are various ways to do it. For me, seems nice, to split the screen into two main sections. a) To have single vertical list with Items and connections to "Question mark", refer to the image below.
Single row in a vertical list
So it's easy to change size to the item list, which you are retrieving from Server, by dynamically adding and removing simple View. Once correct tile would be places on the top of "Question mark" you will change new View on the top of this View. b) To create bottom list with possible "Answers" there will be Horizontal list, with this items. As you mentioned in our question.
Bottom horizontal list
Description
a) I really do't like implementation of such kind of task with Android widgets like RecyclerView. With small list of items, we could bring a lot of customization. For the first list I would use VerticalScrollView with LinearLayout and View (with any your layout).
Note. Your last layout could be ConstraintLayout. Ex. 1. In this case your dragged items would stick on exact places, where you live it. And In case it's stick on specific row with more than half size, you could change view for it (to green or red). Ex 2. Maybe even better way would be animate moving from place where live the tiles, to the nearest "Question mark" with "Property Animation"
b) To create bottom list I would use the same structure with `HorizontalListView". This will help to use "Property Animation" and not just animate dragging, but also move an object with your grading trajectory. Using dynamically added items in the containers with simple views will reflect on changes in bottom, or top lists.
Implementation
1) Initial listeners for each your "Answer" tiles.
// Assign the touch listener to your view which you want to move
findViewById(R.id.myimage1).setOnTouchListener(new MyTouchListener());
// This defines your touch listener
private final class MyTouchListener implements OnTouchListener {
public boolean onTouch(View view, MotionEvent motionEvent) {
if (motionEvent.getAction() == MotionEvent.ACTION_DOWN) {
ClipData data = ClipData.newPlainText("", "");
DragShadowBuilder shadowBuilder = new View.DragShadowBuilder(
view);
view.startDrag(data, shadowBuilder, view, 0);
view.setVisibility(View.INVISIBLE);
return true;
} else {
return false;
}
}
}
2) Define each of your target Views in the top list.
findViewById(R.id.bottomright).setOnDragListener(new MyDragListener());
class MyDragListener implements OnDragListener {
Drawable enterShape = getResources().getDrawable(
R.drawable.shape_droptarget);
Drawable normalShape = getResources().getDrawable(R.drawable.shape);
#Override
public boolean onDrag(View v, DragEvent event) {
int action = event.getAction();
switch (event.getAction()) {
case DragEvent.ACTION_DRAG_STARTED:
// do nothing
break;
case DragEvent.ACTION_DRAG_ENTERED:
v.setBackgroundDrawable(enterShape);
break;
case DragEvent.ACTION_DRAG_EXITED:
v.setBackgroundDrawable(normalShape);
break;
case DragEvent.ACTION_DROP:
// Dropped, reassign View to ViewGroup
View view = (View) event.getLocalState();
ViewGroup owner = (ViewGroup) view.getParent();
owner.removeView(view);
LinearLayout container = (LinearLayout) v;
container.addView(view);
view.setVisibility(View.VISIBLE);
break;
case DragEvent.ACTION_DRAG_ENDED:
v.setBackgroundDrawable(normalShape);
default:
break;
}
return true;
}
}
3) That is it you need to create dragging. Just to make another setup in the Activity and View changes.
However you could check few other examples of drag and drop implementation. But since you were using simple Views and Scrollable containers, you can align every sample to work with your lists.

Keep Android Spinner from dropping list

I have an Android spinner that I would like to disable when there's less than one item in my list. What I mean by that is I would like the title to show up, but I don't want a list to drop down when I click it.
I've tried isClickable = false, and isEnabled = false like in many of the posts out there, but I still can't get it to work.
I successfully get ride of the spinner dropdown icon, but I can still click the text and get the list.
class CustomSpinnerAdapter(private val ctx: Context, val locations: List<Location>) : ArrayAdapter<Location>(ctx, R.layout.list_item_spinner_view) {
override fun isEmpty() = locations.isEmpty()
override fun getView(position: Int, convertView: View?, parent: ViewGroup): View {
val context = parent.context
val inflater = LayoutInflater.from(context)
var view = convertView
if (view == null)
view = inflater.inflate(R.layout.list_item_spinner_view, parent, false)
view!!.location_spinner_name.text = locations[position].name
if (count < 2) {
view.location_spinner.visibility = View.GONE
view.better_name.isEnabled = false
view.better_name.isClickable = false
}
view.location_spinner_name.typeface = Typeface.createFromAsset(ctx.assets, ctx.getString(R.string.font_bold))
return view
}
Here is the view for my title
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:id="#+id/better_name">
<TextView
android:id="#+id/location_spinner_name"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:singleLine="true"
style="#style/TextAppearance.Widget.AppCompat.Toolbar.Title"/>
<com.ge.cbyge.view.TintableImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/ic_arrow_drop_down_black"
android:tint="#color/medium_gray"
android:paddingTop="#dimen/activity_home_spinner_dropdown_padding_top"/>
</LinearLayout>
Hopefully this will be helpful. It is not a re-write of your app, but maybe an idea that you can integrate:
You could create your own Spinner class like this:
class MySpinner extends AppCompatSpinner {
public MySpinner(Context context) {
super(context);
}
public MySpinner(Context context, AttributeSet attrs) {
super(context, attrs);
}
#Override
public boolean performClick() {
if ( getCount() == 0 ) {
return true; // we do nothing because adapter contents = 0
}
else {
return super.performClick(); // we proceed as normal
}
}
}
Then alter your XML references from "Spinner" to "[yourPackageName].MySpinner"

Spinner updating only on user actions

I have IconText that has image and text views inside it, both class and xml.
I then populate the Spinner inside of the MainActivity with these IconTexts, using extended BaseAdapter (IconTextAdapter) as adapter.
Now, IconText works fine (shows as it should).
Spinner however doesn't.
When I start the app, it shows the first IconText as it should.
When I open the choose dialog, everything is showing as it should.
When I select another item, the choose dialog collapses and spinner displays no IconText (ie. only "arrow down" for opening choose dialog).
I can still open the choose dialog and choose another.
I've noticed that if I exit from app (return button, not really quiting the app) and enter again that the proper IconText is shown.
I guess that the fault lies with the adapter?
I will try avoiding posting a lot of code [:
IconText.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="horizontal">
<ImageView android:id="#+id/it_image"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:src="#drawable/home"/>
<TextView
android:id="#+id/it_text"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:paddingLeft="20sp"
android:text="ABC"
android:textColor="#color/black_overlay"
android:textSize="20sp"
android:textStyle="bold" />
</LinearLayout>
IconText.java
public class IconText {
static LayoutInflater inflator;
public ImageView icon;
public TextView text;
public View view;
public IconText(String title, int icon_id){
Log.d("IconText", "Create");
view = inflator.inflate(R.layout.icon_text, null);
text = (TextView) view.findViewById(R.id.it_text);
icon = (ImageView) view.findViewById(R.id.it_image);
text.setText(title);
icon.setImageResource(icon_id);
}
public static void initInflator(Context context){
if(inflator != null) return;
Log.d("IconText", "Init inflator");
inflator = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
}
}
IconTextAdapter.java
public class IconTextAdapter extends BaseAdapter implements SpinnerAdapter{
public ArrayList<IconText> items;
public IconTextAdapter(){
super();
items = new ArrayList<>();
}
#Override
public int getCount() {
return items.size();
}
#Override
public Object getItem(int arg0) {
return items.get(arg0);
}
#Override
public long getItemId(int position) {
return items.get(position).view.getId();
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
return items.get(position).view;
}
}
MainActivity, relevant code
void initFilter(){
Log.d("MainAction", "Find Filter");
filter = (Spinner) findViewById(R.id.filter);
Log.d("MainAction", "Create Adapter");
IconTextAdapter adapter = new IconTextAdapter();
Log.d("MainAction", "Create items");
for(int i=0; i<ETypes.names.length; i++){
IconText it = new IconText(ETypes.names[i], ETypes.icons[i]);
adapter.items.add(it);
}
Log.d("MainAction", "Setting adapter");
filter.setAdapter(adapter);
}
ETypes names[string] and icons[id] are static.
Inflator is initialized succesfully.
I haven't worked much in Android. If it were Java/Swing, I guess I would just call a redraw or something.
I know there are some bad practices here (all public variables, and so on). This code is still in early prototype stage, it will be fixed soon. I'm not looking for optimization, just for the solution to my problem.
Update 1:
So I saw I didn't implement getDropDownView so I did, the same code as getView (no need to post it?).
Also I made an experiment: At the end of IconText contrusctor I added
view = text
And it works just fine (showing only text).
I guess this pinpoints that the problem originates from custom view?
Update 2:
Did another experiment with IconText, setting view = icon; and it doesn't behave as it should, ie. it behaves like it's a custom view.
Doesn't really solve this specific bug, but it solves my problem.
Custom Image and Text View in Spinner Solution.
To update the list you must call
adapter.notifyDataSetChanged()
after adding new data to your adapter
Please refer to the following
https://developer.android.com/reference/android/widget/BaseAdapter.html#notifyDataSetChanged()

Glide overlays screen with loaded image parts

Since i could not find anything related in the internet, this is gonna be my first SO question:
Problem Description
I am experiencing the following issue:
In my app i have a RecyclerView with a GridLayoutManager which is displaying images loaded by Glide.
When scrolling slowly everything will work alright.
After scrolling fast up and down (to an extend one could arguably call it "abuse of scrolling") some image parts or whole images will randomly overlay my screen, so that the content below is no longer visible. This is especially the case on the edges of the screen.
The testing device where the described error occurs is a OnePlus One running CM12.1.1 (Android 5.1.1). I didn't test on other devices.
Any hints / help / explanation on why this is happening or how to fix it are appreciated.
CODE
Below is the code for the Adapter with an inner ViewHolder class:
public class PhotoListAdapter extends RecyclerView.Adapter<PhotoListAdapter.PhotoHolder>{
private ArrayList<PhotoDetail> mPhotos;
private String mAccessToken;
private int mUserId;
private int mPageCounter = 1;
private boolean mIsLoading = false;
private boolean mEndReached = false;
public PhotoListAdapter (String accessToken, int userId){
mPhotos = new ArrayList<>();
mAccessToken = accessToken;
mUserId = userId;
fetchPhotos();
}
#Override
public PhotoHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View itemView = LayoutInflater.from(parent.getContext()).inflate(R.layout.fragment_photo_list_item, parent, false);
PhotoHolder photoHolder = new PhotoHolder(itemView);
return photoHolder;
}
#Override
public void onBindViewHolder(PhotoHolder holder, int position) {
holder.bind(mPhotos.get(position));
if (position == mPhotos.size() - 6) fetchPhotos();
}
#Override
public int getItemCount() {
return mPhotos.size();
}
public void fetchPhotos () {
if (mIsLoading || mEndReached) return;
else {
mIsLoading = true;
//Retrofit call which will return a JSON Object with the Photo Details, like the filename
// With this information i can build the URL of the image
ApiProvider.getInstance().getApi().getPhotos(mUserId, mAccessToken, "time", "all", mPageCounter, mUserId, 32).enqueue(new Callback<PhotoResponseWrapper>() {
#Override
public void onResponse(Call<PhotoResponseWrapper> call, Response<PhotoResponseWrapper> response) {
if (response.code() == HttpURLConnection.HTTP_OK){
int photoCount = response.body().getPhotoResponse().getPhotosCount();
if (photoCount != 32) mEndReached = true;
Collections.addAll(mPhotos, response.body().getPhotoResponse().getPhotos());
notifyItemRangeInserted(mPhotos.size() - photoCount,photoCount);
mPageCounter++;
}
mIsLoading = false;
}
#Override
public void onFailure(Call<PhotoResponseWrapper> call, Throwable t) {
mIsLoading = false;
}
});
}
}
class PhotoHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
private ImageView mPhotoView;
private PhotoDetail mPhotoDetail;
public PhotoHolder(View itemView) {
super(itemView);
mPhotoView = (ImageView) itemView.findViewById(R.id.img_photo);
mPhotoView.setOnClickListener(this);
}
public void bind (PhotoDetail photoDetail){
mPhotoDetail = photoDetail;
String photoUrl = Api.Endpoints.PHOTOS_SMALL + photoDetail.getUserId() + '/' + photoDetail.getFileName();
mPhotoView.setContentDescription(photoDetail.getDescription());
// First stop all pending image loads
Glide.clear(mPhotoView);
// Then load new url
Glide.with(mPhotoView.getContext())
.load(photoUrl)
.into(mPhotoView);
}
#Override
public void onClick(View v) {
}
}
}
Below is the XML of a single Item:
<?xml version="1.0" encoding="utf-8"?>
<ImageView
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/img_photo"
android:clickable="true"
android:layout_width="match_parent"
android:layout_height="#dimen/height_photo_item"
android:padding="#dimen/padding_photo_item"
android:scaleType="centerCrop"/>
Below is the XML of the RecyclerView:
<android.support.v4.widget.SwipeRefreshLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/layout_swipe_refresh"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingRight="#dimen/padding_photo_item"
android:paddingLeft="#dimen/padding_photo_item"
android:paddingTop="#dimen/padding_photo_item"
tools:context=".fragments.PhotoListFragment">
<android.support.v7.widget.RecyclerView
android:id="#+id/recycler_view"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</android.support.v4.widget.SwipeRefreshLayout>
EXAMPLES
Some visual examples of the bug are these screenshots:
You have to use placeholder image.
Glide.with(mPhotoView.getContext())
.load(photoUrl)
.placeholder(R.drawable.image_placeholder) // Your placeholder image
.into(mPhotoView);
I had the same problem and setting the placeholder eliminated it for me.
Since I couldn't find any information on how to fix this, i tried out the major alternative image loading & caching library - Picasso.
With this library the bug mentioned above wasn't reproducible for me, so i guess it is really Glide specific.

Hide Android-PullToRefresh along with Action Bar

I have three tabs and hiding the Action Bar on the middle tab. The third tab had pull to refresh. Android does a great job of animating the sliding in and out of the Action Bar but when I pull to refresh on the third tab and switch to the middle tab (where the Action Bar is hidden) I see the following:
The action bar is hidden from the PageAdapter and hidden as follows:
#Override
public void onPageSelected(int position) {
if (position == 1) {
mActionBar.hide();
} else {
mActionBar.show();
}
}
Pull to Refresh is implemented in a fragment (third tab) with the layout as:
<?xml version="1.0" encoding="utf-8"?>
<uk.co.senab.actionbarpulltorefresh.extras.actionbarsherlock.PullToRefreshLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/ptr_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#color/grey_canvas_bg"
android:orientation="vertical"
>
<se.emilsjolander.stickylistheaders.StickyListHeadersListView
android:id="#+id/list_feed"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</uk.co.senab.actionbarpulltorefresh.extras.actionbarsherlock.PullToRefreshLayout>
and initialised in the OnCreateView as follows:
mPullToRefreshLayout = (PullToRefreshLayout) view.findViewById(R.id.ptr_layout);
ActionBarPullToRefresh.from(getActivity())
.allChildrenArePullable()
.useViewDelegate(StickyListHeadersListView.class, new ViewDelegate() {
#Override
public boolean isReadyForPull(View view, float v, float v2) {
View childView = updatesListView.getChildAt(0);
int top = (childView == null) ? 0 : childView.getTop();
return top >= 0;
}
})
.listener(this)
.setup(mPullToRefreshLayout);
Thanks for any help!

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