Develop Reference

How to add recylerview in 1/3rd part of activity

I have on activity in which i need to add one horizontal list for showing the formats of image which should be appear in the lower part of the activity. Here is my xml file.
<?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"
android:background="#color/white"
android:fitsSystemWindows="true"
tools:context=".view.quickaction.QuickActionVideoActivity">
<RelativeLayout
android:id="#+id/quick_action_video_header_contatiner"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginLeft="20dp"
android:orientation="vertical"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent">
<TextView
android:id="#+id/quick_action_video_close"
android:layout_width="match_parent"
android:layout_height="25dp"
android:layout_marginTop="20dp"
android:text="#string/button_cancel"
android:textColor="#color/express_purple"
android:textSize="18dp" />
<TextView
android:id="#+id/quick_action_video_title"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="#id/quick_action_video_close"
android:layout_marginTop="30dp"
android:fontFamily="#font/adobe_clean_bold"
android:text="#string/quick_action_resize_video_header"
android:textColor="#color/black_alpha_85"
android:textSize="32dp" />
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="#id/quick_action_video_title"
android:text="#string/powered_by_magicX"
android:textColor="#color/black_alpha_85"
android:textSize="14dp" />
</RelativeLayout>
<androidx.constraintlayout.widget.ConstraintLayout
android:id="#+id/zoom_surface"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_marginStart="15dp"
android:layout_marginTop="30dp"
android:layout_marginEnd="15dp"
android:background="#drawable/rounded_rectangle_rect"
android:visibility="visible"
app:layout_constraintDimensionRatio="H,5:4"
app:layout_constraintEnd_toStartOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#id/quick_action_video_header_contatiner">
<com.otaliastudios.zoom.ZoomSurfaceView
android:id="#+id/surface_view"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_marginTop="25dp"
android:layout_marginBottom="25dp"
app:horizontalPanEnabled="true"
app:verticalPanEnabled="true"
app:zoomEnabled="true" />
</androidx.constraintlayout.widget.ConstraintLayout>
<RelativeLayout
android:id="#+id/relativeLayout3"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="#+id/zoom_surface"
app:layout_constraintBottom_toTopOf="#id/relativeLayout2"
tools:ignore="MissingConstraints">
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/rvList"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="15dp"
android:orientation="horizontal"
app:layout_constrainedHeight="true"/>
</RelativeLayout>
<RelativeLayout
android:id="#+id/relativeLayout2"
android:layout_width="0dp"
android:layout_height="wrap_content"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent">
<Button
android:id="#+id/quick_action_video_save_button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:layout_marginTop="12dp"
android:layout_marginBottom="12dp"
android:layout_weight="1"
android:background="#drawable/button_bg_rounded_corners"
android:fontFamily="#font/adobe_clean_bold"
android:text="#string/save_share_option"
android:textColor="#color/white_alpha_80" />
</RelativeLayout>
</androidx.constraintlayout.widget.ConstraintLayout>
It should look like this:
But this recyler-view while loading taking the whole space of the activity and one header also. Can you tell me what is wrong in this? Can recyler-view won't be able to host inside this view.

The issue is that you don't have a top to bottom of constraint and have set the height as match constraints.. However for layouts like this i have a few tips..
do the layouts first with constant heights like 200 dp or so and change them later
follow a top to bottom or a bottom to top approach that is one view at the top and everything else is done taking that as anchor
use constraint layouts throughout. You don't need any other layout type if you're using constraint layout
<androidx.constraintlayout.widget.ConstraintLayout
android:id="#+id/zoom_surface"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_marginStart="15dp"
android:layout_marginTop="30dp"
android:layout_marginEnd="15dp"
android:background="#drawable/rounded_rectangle_rect"
android:visibility="visible"
app:layout_constraintDimensionRatio="H,5:4"
app:layout_constraintEnd_toStartOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#id/quick_action_video_header_contatiner"
app:layout_constraintBottom_toTopOf=" ">add the suitable id
<com.otaliastudios.zoom.ZoomSurfaceView
android:id="#+id/surface_view"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_marginTop="25dp"
android:layout_marginBottom="25dp"
app:horizontalPanEnabled="true"
app:verticalPanEnabled="true"
app:zoomEnabled="true" />
</androidx.constraintlayout.widget.ConstraintLayout>

windowSoftInput hides items in recycleview

Im creating a chat app and so far it looks something like this:
The moment I start typing it hides the last 2 items and looks like (the edittext hides g,h messages):
My XML file looks as follows:
<?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=".ChatActivity">
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/rv_Messages"
android:layout_width="match_parent"
android:layout_height="0dp"
app:layout_constraintHeight_percent="0.9"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<ImageButton
android:id="#+id/ib_Send"
style="?android:borderlessButtonStyle"
android:layout_width="wrap_content"
android:layout_height="0dp"
android:layout_marginEnd="8dp"
android:layout_marginRight="8dp"
android:adjustViewBounds="true"
android:src="#drawable/ic_location_on_black_24dp"
app:layout_constraintHeight_percent="0.1"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent" />
<EditText
android:id="#+id/et_Message"
android:layout_width="0dp"
android:layout_height="0dp"
android:layout_marginEnd="8dp"
android:layout_marginStart="8dp"
android:hint="enter message here"
android:backgroundTint="#color/colorLightPurple"
android:inputType="textMultiLine|textPersonName"
app:layout_constraintHeight_percent="0.1"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toStartOf="#+id/ib_Send"
app:layout_constraintStart_toStartOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
and I have added to my manifest android:windowSoftInputMode="adjustPan"
Is there a way that I can make sure that my recycleview will always show the lates messages/ make sure the edittext wont hide?
Thank you

Use the combination of relative and linear layout and then use marginBottom inside recyclerview. Hope you will find it.
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 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=".ChatActivity">
<include
android:id="#+id/chat_toolbar"
layout="#layout/app_bar_layout">
</include>
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/private_messages_list_of_users"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_below="#+id/chat_toolbar"
android:layout_above="#+id/chat_linear_layout"
android:layout_marginBottom="6dp"
>
</androidx.recyclerview.widget.RecyclerView>
<RelativeLayout
android:id="#+id/chat_linear_layout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentStart="true"
android:layout_alignParentBottom="true"
android:background="#android:color/background_light"
android:orientation="horizontal"
>
<ImageButton
android:id="#+id/send_files_btn"
android:layout_width="60dp"
android:layout_height="50dp"
android:src="#drawable/ic_attach_file_black_24dp"
android:layout_alignParentStart="true"
android:backgroundTint="#android:color/white"
/>
<EditText
android:id="#+id/input_message"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:hint="type message here..."
android:padding="15dp"
android:maxLines="5"
android:layout_toEndOf="#+id/send_files_btn"
android:layout_toStartOf="#+id/send_message_btn"
/>
<ImageButton
android:id="#+id/send_message_btn"
android:layout_width="60dp"
android:layout_height="wrap_content"
android:src="#drawable/send_message"
android:layout_alignParentEnd="true"
android:backgroundTint="#android:color/white"
/>
</RelativeLayout>
</RelativeLayout>
check out my above example...

Wrong app display on both physical and virtual device

I tried on both emulator and physical device ,with different layouts, but app shows only about sixty percent of layout,like its exceeding the visible screen and some component goes under.
I tried to use a scroll view,but no success.
<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:background="#242323"
tools:context=".MainActivity">
<RelativeLayout
android:layout_width="395dp"
android:layout_height="715dp"
tools:layout_editor_absoluteX="8dp"
tools:layout_editor_absoluteY="8dp">
<EditText
android:id="#+id/edittext"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:hint="blah blah"
android:layout_centerHorizontal="true"
android:layout_centerVertical="true"
/>
<Button
android:id="#+id/button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="press"
android:layout_centerHorizontal="true"
android:layout_below="#id/edittext"
/>
</RelativeLayout>
</androidx.constraintlayout.widget.ConstraintLayout>

In your code,try to change this:
from
<RelativeLayout
android:layout_width="395dp"
android:layout_height="715dp"
tools:layout_editor_absoluteX="8dp"
tools:layout_editor_absoluteY="8dp">
to
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
tools:layout_editor_absoluteX="8dp"
tools:layout_editor_absoluteY="8dp">

When using constraint layout you need to link your views to some other view/boundry. In your case your RelativeLayout was not linked to parent, and you were using an extra Layout so remove the Constraint layout and use just Relative layout.
That will work.
Try the following xml
<RelativeLayout 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="#242323"
tools:context=".MainActivity">
<EditText
android:id="#+id/edittext"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:hint="blah blah"
android:layout_centerHorizontal="true"
android:layout_centerVertical="true"
/>
<Button
android:id="#+id/button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="press"
android:layout_centerHorizontal="true"
android:layout_below="#id/edittext"
/>
</RelativeLayout>

Remove the relative layout and just use constraint layout only. Note that your button and edittext have to be constrained to the parent view. Learn more about Constraint Layout at https://developer.android.com/reference/android/support/constraint/ConstraintLayout
Try the following xml
<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:background="#242323"
tools:context=".MainActivity">
<EditText
android:id="#+id/edittext"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_centerVertical="true"
android:layout_marginStart="8dp"
android:layout_marginTop="8dp"
android:layout_marginEnd="8dp"
android:layout_marginBottom="8dp"
android:hint="blah blah"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<Button
android:id="#+id/button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#id/edittext"
android:layout_centerHorizontal="true"
android:layout_marginStart="8dp"
android:layout_marginTop="8dp"
android:layout_marginEnd="8dp"
android:layout_marginBottom="8dp"
android:text="press"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/edittext" />
</androidx.constraintlayout.widget.ConstraintLayout>

RecycleView get cuts at Bottom

This question is raised by so many people but for my case those solution and tips are not working.
I'm using RecycleView in fragment to display gridview for product display but is't cut last item at bottomside, I have gone through many solution like android:clipToPadding="false" and android:paddingBottom="myactionbarsize" but eventually it's doen't work.
Have a look at my code
<?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"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/ll_parent_vendors"
android:background="#color/bg_main">
<android.support.v7.widget.RecyclerView
android:id="#+id/rv_vendors"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
android:clipToPadding="false"
/>
<TextView
android:id="#+id/txt_empty_vendors"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text=""
android:textColor="#color/edt_hint_color"
android:textSize="#dimen/TextSizeNormal"
android:visibility="gone"
android:layout_margin="16dp"
android:padding="16dp"
android:gravity="center"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
</android.support.constraint.ConstraintLayout>
Here is my item Xml code
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/ll_row_vendor_services"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#color/colorAccent"
android:orientation="vertical"
android:padding="1dp">
<com.customview.SquareImageView
android:id="#+id/img_vendor_services"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#drawable/ic_placeholder"
android:scaleType="fitXY" />
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="bottom"
android:background="#ffffff"
android:orientation="horizontal">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginLeft="4dp"
android:layout_weight="1"
android:gravity="center"
android:orientation="vertical">
<TextView
android:id="#+id/txt_service_title"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:ellipsize="end"
android:lines="1"
android:text="#string/app_name"
android:textColor="#color/edt_color"
android:textSize="#dimen/TextSizeSmall" />
<TextView
android:id="#+id/txt_service_price"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:text="#string/app_name"
android:textColor="#color/colorAccent"
android:textSize="#dimen/TextSizeSmall" />
</LinearLayout>
<LinearLayout
android:id="#+id/ll_chat"
android:layout_width="50dp"
android:layout_height="match_parent"
android:gravity="center">
<ImageView
android:layout_width="25dp"
android:layout_height="25dp"
android:background="#drawable/ic_chat"
android:clickable="false"
android:tint="#color/colorAccent" />
</LinearLayout>
</LinearLayout>
</FrameLayout>
and how I initialize in my fragment
rv_vendors = view.findViewById(R.id.rv_vendors);
rv_vendors.setHasFixedSize(true);
rv_vendors.setLayoutManager(new GridLayoutManager(mContext, 2));
Here are my Screenshot of emulator Pixel API 24 which cuts the layout at bottom.
and other one which is MIA1 real device Screenshot it's perfect with same propertie.
how this happens any hints ?

android scrollview not scrolling down after keyboard opens

I have a textview that is inside of a scrollview, it scrolls fine untill the soft keyboard is opened.
When the keyboard is opened it act like it scrolled up again with the height of the keyboard.
What I have tried
I tried this in the manifest, but yielded the exact same results
android:windowSoftInputMode="adjustResize"
Then this:
android:windowSoftInputMode="adjustPan"
That seemed to work, but the problem was that it was moving the whole screen up and taking the header out of view.
I also tried adding the following in the linear layout
android:focusable="true"
android:focusableInTouchMode="true"
That only caused the app not to focus on the input field (EditText) and the keyboard didn't open automatically, but when you clicked on the input field it would just act the same as before.
This is the XML file code:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#color/lightGray"
android:orientation="vertical" >
<ScrollView
android:id="#+id/scrollView"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_above="#+id/bottom_layout"
android:layout_marginTop="10dip" >
<LinearLayout
android:id="#+id/msg_list_layout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
</LinearLayout>
</ScrollView>
<RelativeLayout
android:id="#+id/bottom_layout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:background="#android:color/background_light">
<Button
android:id="#+id/send_btn"
style="?android:attr/buttonStyleSmall"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:text="#string/txt_send" />
<EditText
android:id="#+id/msg_edit"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignBottom="#+id/send_btn"
android:layout_toLeftOf="#+id/send_btn"
android:inputType="text" >
</EditText>
</RelativeLayout>
Any suggestions?

I had same problem and the solutions is this:
My activity was in fullscreen mode and scroll does not work in this mode this is a bug and we send a report to google.
Just look at your activity in manifest if there is a fullscreen mode just remove it.

I got this problem and it is a headache.
the soloution is instead of drawing an XML layout from the top of the screen, you need to draw it from the bottom of the screen.
look at these examples :
main.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"
android:layout_width="match_parent"
android:layout_height="match_parent">
<ScrollView
android:layout_width="0dp"
android:layout_height="match_parent"
android:fillViewport="true"
android:isScrollContainer="true"
android:orientation="vertical"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent">
<include layout="#layout/main_contents"/>
</ScrollView>
</android.support.constraint.ConstraintLayout>
main_contents.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"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="20dp">
<android.support.constraint.Guideline
android:id="#+id/guideline"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="horizontal"
app:layout_constraintGuide_percent="0.92" />
<android.support.v7.widget.CardView
android:id="#+id/card1"
android:layout_width="0dp"
android:layout_height="250dp"
android:layout_margin="30dp"
android:padding="10dp"
app:cardCornerRadius="10dp"
app:layout_constraintBottom_toTopOf="#+id/guideline"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent">
<android.support.constraint.ConstraintLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:id="#+id/sam3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="16dp"
android:text="sample"
android:textColor="#673AB7"
android:textSize="23sp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<EditText
android:id="#+id/sam2"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="right|center_vertical"
android:backgroundTint="#673AB7"
android:digits="0123456789"
android:gravity="center"
android:hint="sample"
android:inputType="phone"
android:maxLength="11"
android:maxLines="1"
android:nextFocusDown="#id/sam1"
android:textColor="#673AB7"
android:layout_marginStart="40dp"
android:layout_marginEnd="40dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/sam3"
app:layout_constraintVertical_bias="0.3"/>
</android.support.constraint.ConstraintLayout>
</android.support.v7.widget.CardView>
<Button
android:id="#+id/sam1"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:textColor="#fff"
android:background="#673AB7"
android:text="sample"
android:layout_marginLeft="60dp"
android:layout_marginRight="60dp"
android:textSize="18sp"
app:layout_constraintBottom_toBottomOf="#+id/card1"
app:layout_constraintEnd_toEndOf="#+id/card1"
app:layout_constraintStart_toStartOf="#+id/card1"
app:layout_constraintTop_toBottomOf="#+id/card1" />
</android.support.constraint.ConstraintLayout>
main_contents2.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:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="20dp">
<android.support.constraint.Guideline
android:id="#+id/guideline"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="horizontal"
app:layout_constraintGuide_percent="0.45" />
<android.support.v7.widget.CardView
android:id="#+id/card1"
android:layout_width="0dp"
android:layout_height="250dp"
android:layout_margin="30dp"
android:padding="10dp"
app:cardCornerRadius="10dp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="#+id/guideline">
<android.support.constraint.ConstraintLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<EditText
android:id="#+id/sam2"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="right|center_vertical"
android:layout_marginStart="40dp"
android:layout_marginEnd="40dp"
android:backgroundTint="#673AB7"
android:digits="0123456789"
android:gravity="center"
android:hint="sample"
android:inputType="phone"
android:maxLength="11"
android:maxLines="1"
android:nextFocusDown="#id/sam1"
android:textColor="#673AB7"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/sam3"
app:layout_constraintVertical_bias="0.3" />
<TextView
android:id="#+id/sam3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="16dp"
android:text="sample"
android:textColor="#673AB7"
android:textSize="23sp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
</android.support.constraint.ConstraintLayout>
</android.support.v7.widget.CardView>
<Button
android:id="#+id/sam1"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:textColor="#fff"
android:background="#673AB7"
android:text="sample"
android:layout_marginLeft="60dp"
android:layout_marginRight="60dp"
android:textSize="18sp"
app:layout_constraintBottom_toBottomOf="#+id/card1"
app:layout_constraintEnd_toEndOf="#+id/card1"
app:layout_constraintStart_toStartOf="#+id/card1"
app:layout_constraintTop_toBottomOf="#+id/card1" />
</android.support.constraint.ConstraintLayout>
the second XML file main_contents2 drew from top and android just put the EditText from top of the keyboard.BUT the main_contents drawn from the bottom of the screen. so when the soft keyboard comes up the layout resizes.

Try changing the layout_height of scrollview to wrap_content.

All you need to do is
android:isScrollContainer="true"