res/layout/extra_button_row.xml

<?xml version="1.0" encoding="utf-8"?>
<!-- Copyright (C) 2012 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.
-->

<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="@drawable/dialpad_background_opaque">
    <!-- The buttons here have a text label floating off to the side
         (which is necessary because these buttons are used only in
         a few rare states, and the meaning of the icon might not be
         obvious.)  The entire row (button + text) is clickable. -->

    <!-- "Manage conference" -->
    <!-- This button is used only on GSM devices, during a conference call. -->
    <LinearLayout android:id="@+id/manageConferenceButton"
        android:orientation="horizontal"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:paddingStart="@dimen/button_cluster_side_padding"
        android:paddingEnd="@dimen/button_cluster_side_padding"
        android:background="?android:attr/selectableItemBackground">
        <!-- The entire LinearLayout here is clickable, so we don't
             care about clicks on the ImageButton itself. -->
        <ImageButton android:id="@+id/manageConferenceButtonImage"
            android:clickable="false"
            style="@style/InCallExtraRowButton"
            android:src="@drawable/ic_groups_holo_dark"
            android:contentDescription="@string/onscreenManageConferenceText" />
        <TextView android:id="@+id/manageConferenceButtonLabel"
            style="@style/InCallExtraRowButtonLabel"
            android:text="@string/onscreenManageConferenceText" />
    </LinearLayout>

    <!-- CDMA-specific "Merge" -->
    <!-- This button is used only on CDMA devices, where we can't use
         the Merge button in the main button row (because the "Add Call"
         button might need to be enabled at the same time.) -->
    <LinearLayout android:id="@+id/cdmaMergeButton"
        android:orientation="horizontal"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:paddingStart="@dimen/button_cluster_side_padding"
        android:paddingEnd="@dimen/button_cluster_side_padding"
        android:background="?android:attr/selectableItemBackground">
        <!-- The entire LinearLayout here is clickable, so we don't
             care about clicks on the ImageButton itself. -->
        <ImageButton android:id="@+id/cdmaMergeButtonImage"
            android:clickable="false"
            style="@style/InCallExtraRowButton"
            android:src="@drawable/ic_merge_holo_dark"
            android:contentDescription="@string/onscreenMergeCallsText" />
        <TextView android:id="@+id/cdmaMergeButtonLabel"
            style="@style/InCallExtraRowButtonLabel"
            android:text="@string/onscreenMergeCallsText" />
    </LinearLayout>

</FrameLayout>