I’m trying to get a popup to show up when I press a button. I wanted to make sure it even shows up before working on the details but the app just crashes when i press it. The commented block is what I originally intended the button to do (just adding an item to the recyclerview) but I decided I wanted to do something a bit different. It only had the problem of crashing when I started adding the popup window stuff. The app still runs fine even if I remove the popup window stuff and leave the commented block commented out. So I don’t know if the listadapter class is relevant but ill just include it.
MainActivity.kt
class MainActivity : AppCompatActivity() {
private lateinit var listAdapter: ListAdapter
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
listAdapter = ListAdapter(mutableListOf())
recyclerView.adapter = listAdapter
recyclerView.layoutManager = LinearLayoutManager(this)
btn_add.setOnClickListener {
/*
//get text from textbox
val itemText = et_reminder.text.toString()
if (itemText.isNotEmpty()){
//create item with text
val item = Item (itemText)
//add to list
listAdapter.addItem((item))
//clear textbox
et_reminder.text.clear()
}*/
val view : View = LayoutInflater.from(applicationContext).inflate (R.layout.popup_s,null)
val popup: PopupWindow = PopupWindow(view, 250, 250,true)
popup.showAtLocation(view, Gravity.NO_GRAVITY, 0,0)
}
}
}
ListAdapter.kt
class ListAdapter(
private val items: MutableList<Item>
): RecyclerView.Adapter<ListAdapter.ListViewHolder>()
{
class ListViewHolder(itemView: View):RecyclerView.ViewHolder(itemView)
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ListViewHolder {
val itemView: View =
LayoutInflater.from(parent.context).inflate (R.layout.list_item, parent, false)
return ListViewHolder(itemView)
}
override fun onBindViewHolder(holder: ListViewHolder, position: Int) {
val curr_item = items [position]
holder.itemView.apply {
tv_reminder.text = curr_item.text;
cb_check.isChecked = curr_item.checked
cb_check.setOnCheckedChangeListener { _, isChecked ->
//changing status of checked
curr_item.checked = isChecked
for (i in items.indices.reversed()) {
if (items[i].checked) {
items.removeAt(i)
notifyItemRemoved(i)
}
}
}
}
}
override fun getItemCount(): Int {
return items.size
}
fun addItem (new_item: Item){
items.add (new_item)
notifyItemInserted(items.size - 1)
}
}
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
<androidx.recyclerview.widget.RecyclerView
android:id="@+id/recyclerView"
android:layout_width="match_parent"
android:layout_height="0dp"
android:background="@color/basically_black"
app:layout_constraintBottom_toTopOf="@+id/et_reminder"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<EditText
android:id="@+id/et_reminder"
android:layout_width="0dp"
android:layout_height="45dp"
android:hint="Reminder"
android:textSize="20sp"
android:textColorHint="@color/white_purple"
android:textColor="@color/white_purple"
android:background="@color/basically_black"
android:paddingStart="10dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toStartOf="@+id/btn_add"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@id/recyclerView"/>
<Button
android:id="@+id/btn_add"
android:layout_width="45dp"
android:layout_height="wrap_content"
android:text="+"
android:textSize="20sp"
android:background="@color/basically_black"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
list_item.xml
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="55dp"
android:paddingStart="10dp">
<TextView
android:id="@+id/tv_reminder"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:paddingTop="0dp"
android:text="temp"
android:textColor="@color/white_purple"
android:textSize="20sp"
android:maxLines="1"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toStartOf="@+id/cb_check"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<CheckBox
android:id="@+id/cb_check"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
popup_s.xml
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true">
<EditText
android:id="@+id/et_r"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:hint="Reminder"
android:textColor="@color/white_purple"
android:textColorHint="@color/gray"
android:textSize="20sp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="1.0"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintVertical_bias="1.0">
</EditText>
</androidx.constraintlayout.widget.ConstraintLayout>
Answer
I think that happen because you are trying to pass applicationContext it will give you Unable to add window — token null is not valid; is your activity running?
try to pass the current activity context instead cause PopupWindow can only be attached to an Activity
val view : View = LayoutInflater.from(this).inflate (R.layout.popup_s,null)
val popup = PopupWindow(view, 250, 250,true)
popup.showAtLocation(view, Gravity.NO_GRAVITY, 0,0)