<com.nikoyuwono.toolbarpanel.ToolbarPanelLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:id="@+id/sliding_down_toolbar_layout"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    app:panelId="@+id/panel"
    app:pullableToolbarId="@+id/toolbar">

    <RelativeLayout
        android:id="@+id/content_container"
        android:layout_width="match_parent"
        android:layout_height="match_parent">
        //Your content here
    </RelativeLayout>

    <android.support.v7.widget.Toolbar
        android:id="@+id/toolbar"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="@color/color_primary" />

    <RelativeLayout
        android:id="@+id/panel"
        android:layout_width="match_parent"
        android:layout_height="match_parent">
        //Your panel content here
    </RelativeLayout>
</com.nikoyuwono.toolbarpanel.ToolbarPanelLayout>

ToolbarPanelLayout.openPanel(); // Open the panel
ToolbarPanelLayout.closePanel(); // Close the panel

/**
 * The drawer is unlocked.
 */
public static final int LOCK_MODE_UNLOCKED = 0;

/**
 * The drawer is locked closed. The user may not open it, though the app may open it
 * programmatically.
 */
public static final int LOCK_MODE_LOCKED_CLOSED = 1;

/**
 * The drawer is locked open. The user may not close it, though the app may close it
 * programmatically.
 */
public static final int LOCK_MODE_LOCKED_OPEN = 2;

/**
 * Called when a panel's position changes.
 */
public void onPanelSlide(Toolbar toolbar, View panelView, float slideOffset);

/**
 * Called when a panel has settled in a completely open state.
 * The panel is interactive at this point.
 */
public void onPanelOpened(Toolbar toolbar, View panelView);

/**
 * Called when a panel has settled in a completely closed state.
 */
public void onPanelClosed(Toolbar toolbar, View panelView);

compile 'com.nikoyuwono:toolbar-panel:0.1.1'

The MIT License (MIT)

Copyright (c) 2015 Niko Yuwono

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.