packages/SystemUI/res/layout/remote_input.xml

<?xml version="1.0" encoding="utf-8"?>

<!--
  ~ Copyright (C) 2015 The Android Open Source Project
  ~
  ~ Licensed under the Apache License, Version 2.0 (the "License");
  ~ you may not use this file except in compliance with the License.
  ~ You may obtain a copy of the License at
  ~
  ~      http://www.apache.org/licenses/LICENSE-2.0
  ~
  ~ Unless required by applicable law or agreed to in writing, software
  ~ distributed under the License is distributed on an "AS IS" BASIS,
  ~ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  ~ See the License for the specific language governing permissions and
  ~ limitations under the License
  -->

<!-- LinearLayout -->
<com.android.systemui.statusbar.policy.RemoteInputView
        xmlns:android="http://schemas.android.com/apk/res/android"
        android:id="@+id/remote_input"
        android:forceHasOverlappingRendering="false"
        android:layout_height="match_parent"
        android:layout_width="match_parent">
    <LinearLayout
        android:layout_height="wrap_content"
        android:layout_width="wrap_content"
        android:id="@+id/remote_input_content"
        android:orientation="vertical"
        android:clipToPadding="false"
        android:layout_marginEnd="0dp"
        android:layout_marginStart="16dp"
        android:layout_marginTop="5dp"
        android:layout_marginBottom="16dp"
        android:layout_weight="1">
        <FrameLayout
            android:id="@+id/remote_input_content_container"
            android:layout_height="66dp"
            android:layout_width="66dp"
            android:layout_marginTop="0dp"
            android:layout_marginStart="4dp"
            android:layout_marginBottom="0dp"
            android:visibility="gone"
            android:layout_gravity="center_vertical">
            <ImageView
                android:id="@+id/remote_input_attachment_image"
                android:layout_width="48dp"
                android:layout_height="48dp"
                android:layout_gravity="start|bottom"
                android:clipToOutline="true"
                android:background="@drawable/rounded_rect_background"
                android:scaleType="centerCrop" />
            <ImageView
                android:id="@+id/remote_input_delete_bg"
                android:paddingTop="6dp"
                android:paddingEnd="6dp"
                android:paddingStart="18dp"
                android:paddingBottom="18dp"
                android:layout_width="48dp"
                android:layout_height="48dp"
                android:layout_gravity="end|top"
                android:src="@drawable/thumbnail_delete_btn_bg"/>
            <ImageView
                android:id="@+id/remote_input_delete"
                android:paddingTop="9dp"
                android:paddingEnd="9dp"
                android:paddingStart="21dp"
                android:paddingBottom="21dp"
                android:layout_width="48dp"
                android:layout_height="48dp"
                android:layout_gravity="end|top"
                android:src="@drawable/ic_close"
                android:contentDescription="@string/notif_inline_reply_remove_attachment_description"/>
        </FrameLayout>

        <view class="com.android.systemui.statusbar.policy.RemoteInputView$RemoteEditText"
                android:id="@+id/remote_input_text"
                android:layout_height="wrap_content"
                android:layout_width="match_parent"
                android:layout_weight="1"
                android:paddingTop="14dp"
                android:paddingStart="4dp"
                android:paddingBottom="16dp"
                android:paddingEnd="12dp"
                android:layout_gravity="start|center_vertical"
                android:textAppearance="?android:attr/textAppearance"
                android:textColor="@color/remote_input_text"
                android:textColorHint="@color/remote_input_hint"
                android:textSize="16sp"
                android:background="@null"
                android:ellipsize="start"
                android:inputType="textShortMessage|textMultiLine|textAutoCorrect|textCapSentences"
                android:imeOptions="actionSend|flagNoExtractUi|flagNoFullscreen" />
    </LinearLayout>

    <FrameLayout
            android:layout_width="56dp"
            android:layout_height="match_parent"
            android:layout_gravity="center_vertical">

        <ImageButton
                android:layout_width="48dp"
                android:layout_height="48dp"
                android:layout_gravity="center_horizontal|bottom"
                android:layout_marginBottom="22dp"
                android:id="@+id/remote_input_send"
                android:src="@drawable/ic_send"
                android:contentDescription="@*android:string/ime_action_send"
                android:tint="@color/remote_input_send"
                android:tintMode="src_in"
                android:background="@drawable/ripple_drawable" />

        <ProgressBar
                android:id="@+id/remote_input_progress"
                android:layout_width="24dp"
                android:layout_height="24dp"
                android:layout_marginBottom="34dp"
                android:layout_gravity="center_horizontal|bottom"
                android:visibility="invisible"
                android:indeterminate="true"
                style="?android:attr/progressBarStyleSmall" />

    </FrameLayout>

</com.android.systemui.statusbar.policy.RemoteInputView>