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BottomSheetDialogFragment is not open, small white bar only show

I have created BottomSheetDialogFragment and access into my fragment but it not open fully, it shows only small bar in bottom like below
I am using default BottomSheetDialogFragment file without changing anything.
xml
<?xml version="1.0" encoding="utf-8"?>
<androidx.recyclerview.widget.RecyclerView
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/list"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:clipToPadding="false"
android:paddingTop="#dimen/list_item_spacing_half"
android:paddingBottom="#dimen/list_item_spacing_half"
tools:context=".ui.SettingFragment"
tools:listitem="#layout/fragment_setting_list_dialog_item" />
Show call function
val addBottomDialogFragment: SettingFragment = SettingFragment.newInstance(10)
addBottomDialogFragment.show(supportFragmentManager, "tag")

Height of BottomSheet depend on child content height So first you should add some child view or content under bottom sheet view. If you using RecyclerView then set adapter with data.

Because your BottomSheet don't have content, You have to add content to it

Your bottom sheet root element should be "Linear Layout" or "Relative Layout" set background to Transparent.

Fragment Button is found by Activity's findViewById instead of Fragment's inflated view.findViewById

I'm seeing this strange behavior and couldn't find anything similar to this.
So I have a parent Activity and inside is a Fragment, which I'm including in parent via include element and then in parent's onCreate, create Fragment and replace it with this include layout (Tell me if this is a right way? I was using FrameLayout but then switched to include and defined an id to it).
Activity
<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"
android:fitsSystemWindows="true"
tools:context="com.sourcey.materiallogindemo.CustomerDetailActivity"
tools:ignore="MergeRootFrame">
<com.google.android.material.appbar.AppBarLayout>
<com.google.android.material.appbar.MaterialToolbar />
</com.google.android.material.appbar.AppBarLayout>
<include
android:id="#+id/fragment_container"
android:layout_width="match_parent"
android:layout_height="0dp"
app:layout_constraintTop_toBottomOf="#id/app_bar"
app:layout_constraintBottom_toTopOf="#id/layout_bottom_bar"
layout="#layout/fragment_customer_detail" />
<androidx.coordinatorlayout.widget.CoordinatorLayout>
<com.google.android.material.bottomappbar.BottomAppBar>
</com.google.android.material.bottomappbar.BottomAppBar>
</androidx.coordinatorlayout.widget.CoordinatorLayout>
</androidx.constraintlayout.widget.ConstraintLayout>
Fragment
<androidx.constraintlayout.widget.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
xmlns:app="http://schemas.android.com/apk/res-auto"
tools:context="com.sourcey.materiallogindemo.CustomerDetailFragment"
android:layout_height="match_parent"
android:layout_width="match_parent">
<!-- THIS IS THE CULPRIT -->
<com.google.android.material.button.MaterialButton
android:id="#+id/btn_update_position"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
<com.google.android.material.button.MaterialButton />
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/sku_list"
app:layoutManager="LinearLayoutManager"
tools:context="com.sourcey.materiallogindemo.CustomerDetailFragment"
tools:listitem="#layout/fragment_s_k_u_item" />
</androidx.constraintlayout.widget.ConstraintLayout>
Fragment is inflated correctly but when I do this inside onCreateView
rootView.btn_update_position.setOnClickListener {
// ... log something
}
and press the Button, it doesn't do anything? Even though most findings were led to this suggestion that I should inflate the view and then set onClickListener.
I also tried doing these
rootView.findViewById<MaterialButton>(R.id.btn_update_position).setOnClickListener {
// ... log something
}
and
val button = rootView.findViewById<MaterialButton>(R.id.btn_update_position)
button.setOnClickListener {
// ... log something
}
but none of them works.
I also tried above approaches in onViewCreated to see if maybe I was not getting the reference but no errors were thrown and no reaction was coming.
Only thing that works is this
activity?.findViewById<MaterialButton>(R.id.btn_update_position)
?.setOnClickListener {
// ... log something
}
I'm trying to understand why this happens? Could this be the issue of using include the Fragment?
NOTE I'm not a pro in android just do hobby work in it so don't know very deeply about it.
EDIT As you can see I have a RecyclerView in Fragment layout, I'm inflating the layout and then setting its adapter items which seems to work fine opposed to button.
rootView.sku_list.adapter = Adapter()

I'm bit confused about what you want to do here
First,<include> doesn't create new view, it just include the xml into the parent xml file so basically it still on activity and you need activity to findViewById
Second, about your question what different between FrameLayout and <include>.
With <include> like i said above, it just add xml file to the parent file, the main usage is for re-use layout (you can include it anywhere) .
With FrameLayout, from official doc : "FrameLayout is designed to block out an area on the screen to display a single item". E.g : you want your layout have a header and footer for all screen, only the middle part change so place a frame layout at middle then load different view for each screen, because that flexibility frame layout usually use for display fragment (you can google how to use frame layout for more details)

How to animate height change of views inside a LinearLayout?

I am working on an Android 4+ app which uses a quite simply layout: Multiple views are stacked using a LinearLayout within a ScrollView
<ScrollView
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
tools:ignore="HardcodedText,UseCompoundDrawables,UselessParent"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:focusableInTouchMode="true">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
<!-- Top Container -->
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
<Button... />
</LinearLayout>
<!-- Hidden Container -->
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
... Some Content ...
</LinearLayout>
<!-- Bottom Container -->
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
... Some Content ...
</LinearLayout>
</LinearLayout>
</ScrollView>
The HiddenContainer should not be visible when the layout it created. Thus in the beginning the BottomContainer is directly beneath the TopContainer. A click on the Button within the TopContainer toggles the visibility of the HiddenContainer.
Doing this with hiddenContainer.setVisibility(hiddenContainer.getVisibility() == View.VISIBLE ? View.GONE : View.VISIBLE) works find and without any problem. However it does not look good when the view suddenly appears or disappears. Instead I would like to animate the change.
I was surprised that I was not able to find an easy solution for this:
Using android:animateLayoutChanges="true" does work, however I am not able to control the animation.
While using a ValueAnimator to change hiddenContainer.setScaleY(...) gives me control over the animation setScaleY(0) makes the container invisible without reducing the space it occupies within the layout.
Using the ValueAnimator to change hiddenContainer.setHeight(...) might work, however I don't want to use a fixed height value when showing the container (e.g. hiddenContainer.setHeight(300)) but the height which is determined by the containers content.
So, how to solve this?

For animate your changes of layout (alpha, visibility, height, etc) you can use TransitionManager. For example: I have three static methods and use them when I want to animate layout changes:
public static final int DURATION = 200;
public static void beginAuto(ViewGroup viewGroup) {
AutoTransition transition = new AutoTransition();
transition.setDuration(DURATION);
transition.setOrdering(TransitionSet.ORDERING_TOGETHER);
TransitionManager.beginDelayedTransition(viewGroup, transition);
}
public static void beginFade(ViewGroup viewGroup) {
Fade transition = new Fade();
transition.setDuration(DURATION);
TransitionManager.beginDelayedTransition(viewGroup, transition);
}
public static void beginChangeBounds(ViewGroup viewGroup) {
ChangeBounds transition = new ChangeBounds();
transition.setDuration(DURATION);
TransitionManager.beginDelayedTransition(viewGroup, transition);
}
And when you want to animate layout changes you can just call one of this methods before layout changings:
beginAuto(hiddenContainerParentLayout);
hiddenContainer.setVisibility(hiddenContainer.getVisibility() == View.VISIBLE ? View.GONE : View.VISIBLE)

findViewById() returns null - what should I do?

I am using a bottomSheetBehavior in my android project. See codes below:
onlineGame.java:
// get the bottom sheet view
ConstraintLayout llBottomSheet = findViewById(R.id.end_of_online_game_bottom_sheet_behavior_cl);
// init the bottom sheet behavior
end_of_online_game_popup = BottomSheetBehavior.from(llBottomSheet);
avtivity_online_game.xml:
.
.
.
<android.support.design.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="match_parent"
tools:context="com.androidsample.BottomSheetActivity">
<!-- include bottom sheet -->
<include
android:id="#+id/includeBottomSheetBehavior"
layout="#layout/test_end_of_online_game_popup" />
</android.support.design.widget.CoordinatorLayout>
.
.
.
test_end_of_online_game_popup.xml:
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.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/end_of_online_game_bottom_sheet_behavior_cl"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#color/cardview_light_background"
android:visibility="gone"
app:behavior_hideable="false"
app:behavior_peekHeight="120dp"
app:layout_behavior="android.support.design.widget.BottomSheetBehavior">
.
.
.
The problem is this line:
ConstraintLayout llBottomSheet = findViewById(R.id.end_of_online_game_bottom_sheet_behavior_cl);
is returning null. I even changed the code place to onResume, but it did not work. When I get another element in test_end_of_online_game_popup, it works well and not null.
What is the problem?
tnx

Two choices:
ConstraintLayout llBottomSheet = findViewById(R.id. includeBottomSheetBehavior);
<include layout="#layout/test_end_of_online_game_popup" />

Try this:
View view = findViewById(R.id.includeBottomSheetBehavior);//firstly get the root view ID
ConstraintLayout llBottomSheet = view.findViewById(R.id.end_of_online_game_bottom_sheet_behavior_cl);

As you are using included layouts :
Use the find view on the id you have given to the include tag
findViewById(R.id.includeBottomSheetBehavior)
Or you can omit the id in the layout tag so that its not overridden.
In the < include > tag, only the layout attribute is required. This attribute, is a reference to the layout file you wish to include. This tag also lets you override a few attributes of the included layout.
The above example shows that you can use android:id to specify the id of the root view of the included layout; it will also override the id of the included layout if one is defined. Similarly, you can override all the layout parameters.
Source : http://www.curious-creature.com/2009/02/25/android-layout-trick-2-include-to-reuse/

How to position a view off-screen in Android layout

I'm using the Scene/Transition system introduced in 4.4 to simply move an image view from the left to the center of the screen. So the layout for my first scene requires the image to be off screen. I tried android:layout_marginRight but that no effect. What is the correct way to do this?

Use the property translationX or translationY with a negative value. This property sets the horizontal/vertical location of this view relative to its left/top position. You will not see the view off screen in the preview. Run your app and the view must be hidden.
Example:
<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">
<android.support.design.widget.FloatingActionButton
android:id="#+id/button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="bottom|start"
android:layout_margin="16dp"
android:translationX="-72dp"/>
</FrameLayout>
And then in the activity or fragment simply invoke the animate() function.
FloatingActionButton button = (FloatingActionButton)findViewById(R.id.button);
button.animate().translationX(0);

Was thinking one could make the image be to the right of something that is already at the right side, that should keep it off screen. Also, potentially just make it "gone" and then on transtion make it appear.