Android Bottom Sheet is a component that slides up from the bottom to up in an application. For example, when you have a video to share and you click on the Share button, it will open a one slider from bottom, which contains available apps in your device.
Sometimes it can also have a menu option. In a simple word, the Android Bottom sheet is an area (surface) that containing extra useful content at the bottom of the screen. It’s hidden in the bottom or partial show to the user will be shown to the user on the action.
In this tutorial, you will learn the following:
- What is Android Bottom Sheet and it’s type
- Example and code of Bottom sheet.
Types of Bottom Sheets
There are two types of bottom sheets, Standard Bottom Sheet and Modal Bottom Sheet.
- Standard bottom sheets: Display content that complements the screen’s primary content. Remain visible screen users can interact with the primary content. Like, google maps are shown at the bottom how much time and km etc detail of the destination from your point. Here user can interact with both the bottom sheet and the remain of screen content.
- Modal bottom sheets: This can be an alternative to inline menus or simple dialogs on mobile, providing room for additional items, longer descriptions, and iconography. They must be dismissed in order to interact with the underlying content. Example share the location in Google Maps.
Bottom Sheet behavior and States :
Bottom sheets have 5 states:
STATE_COLLAPSED: The bottom sheet is visible but only showing its peek height. This state is usually the ‘resting position’ of a Bottom Sheet
STATE_EXPANDED: The bottom sheet is visible and its maximum height and it is neither dragging or settling.
STATE_DRAGGING: The user is actively dragging the bottom sheet up or down.
STATE_SETTLING: The bottom sheet is settling to specific height after a drag/swipe gesture. This will be the peek height, expanded height, or 0, in case the user action caused the bottom sheet to hide.
STATE_HIDDEN: The bottom sheet is no longer visible.
Source : https://material.io/develop/android/components/bottom-sheet-behavior/
Let’s Build an Example of Android Bottom Sheet
Step 1. Create new project “Build Your First Android App in Kotlin“
Step 2. Add following color code in “color.xml” layout file
<?xml version="1.0" encoding="utf-8"?>
<resources>
<color name="colorPrimary">#3F51B5</color>
<color name="colorPrimaryDark">#303F9F</color>
<color name="colorAccent">#FF4081</color>
<color name="colorApp">#049CA2</color>
<color name="colorGrey">#f2f2f2</color>
<color name="colorWhite">#FFFFFF</color>
</resources>
Step 3. Create “bottom_sheet.xml” and Add code
This will be use for standard bottom sheet.
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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/bottom_sheet"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="@color/colorWhite"
android:orientation="vertical"
android:paddingBottom="10dp"
app:behavior_hideable="true"
app:behavior_peekHeight="56dp"
app:layout_behavior="android.support.design.widget.BottomSheetBehavior">
<TextView
android:layout_width="match_parent"
android:layout_height="56dp"
android:layout_gravity="center"
android:background="@color/colorPrimary"
android:gravity="center"
android:text="About"
android:textColor="@android:color/white"
android:textSize="22sp" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_margin="16dp"
android:text="About : tutorial.eyehunt.in" />
<Button
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="30dp"
android:text="Done" />
</LinearLayout>Step 4. Create “bottom_sheet_dialog.xml” and Add code
You must add image in mipmap folder.
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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:orientation="vertical"
android:padding="16dp">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:clickable="true"
android:foreground="?attr/selectableItemBackground"
android:orientation="horizontal"
android:padding="8dp">
<ImageView
android:layout_width="24dp"
android:layout_height="24dp"
android:layout_marginRight="32dp"
android:src="@mipmap/baseline_share_black_24dp"
android:tint="#737373" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_vertical"
android:text="Share File"
android:textColor="#737373"
android:textSize="16sp" />
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:clickable="true"
android:foreground="?attr/selectableItemBackground"
android:orientation="horizontal"
android:padding="8dp">
<ImageView
android:layout_width="24dp"
android:layout_height="24dp"
android:layout_marginRight="32dp"
android:src="@mipmap/baseline_cloud_upload_black_24dp"
android:tint="#737373" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_vertical"
android:text="Upload"
android:textColor="#737373"
android:textSize="16sp" />
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:clickable="true"
android:foreground="?attr/selectableItemBackground"
android:orientation="horizontal"
android:padding="8dp">
<ImageView
android:layout_width="24dp"
android:layout_height="24dp"
android:layout_marginRight="32dp"
android:src="@mipmap/baseline_cloud_download_black_24dp"
android:tint="#737373" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_vertical"
android:text="Download"
android:textColor="#737373"
android:textSize="16sp" />
</LinearLayout>
</LinearLayout>Step 5. Create “main_content.xml” and Add code
Its your app main content with 2 Button to perform a show and hide Android Bottom Sheet.
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@color/colorGrey"
tools:context=".MainActivity"
tools:showIn="@layout/activity_main">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="30dp"
android:orientation="vertical"
android:padding="10dp"
android:paddingBottom="20dp">
<Button
android:id="@+id/btBottomSheet"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Bottom Sheet" />
<Button
android:id="@+id/btBottomSheetDialog"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="5dp"
android:text="Bottom Sheet Dialog" />
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="8dp"
android:paddingBottom="30dp"
android:text="Android Bottom Sheet Example"
android:textSize="18dp" />
</LinearLayout>
</LinearLayout>
Step 6. Add following code in “activity_main.xml“
A holding all xml file (main_content.xml & bottom_sheet.xml) in one place, using <include>...</include>. its a good practice to use if your screen have common or long code.
<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true"
tools:context=".MainActivity">
<include layout="@layout/main_content" />
<!-- Adding bottom sheet after main content -->
<include layout="@layout/bottom_sheet" />
</android.support.design.widget.CoordinatorLayout>
Step 7. Open the “MainActivity.kt” and add following code
Setting a listener in button and handling behaviour or bottom sheet.
package `in`.eyehunt.androidbottomsheet
import android.support.v7.app.AppCompatActivity
import android.os.Bundle
import android.support.design.widget.BottomSheetBehavior
import android.support.design.widget.BottomSheetDialog
import android.view.View
import android.widget.LinearLayout
import kotlinx.android.synthetic.main.bottom_sheet.*
import kotlinx.android.synthetic.main.main_content.*
class MainActivity : AppCompatActivity() {
private lateinit var sheetBehavior: BottomSheetBehavior<LinearLayout>
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
sheetBehavior = BottomSheetBehavior.from<LinearLayout>(bottom_sheet)
/**
* bottom sheet state change listener
* we are changing button text when sheet changed state
* */
sheetBehavior.setBottomSheetCallback(object : BottomSheetBehavior.BottomSheetCallback() {
override fun onStateChanged(bottomSheet: View, newState: Int) {
when (newState) {
BottomSheetBehavior.STATE_HIDDEN -> {
}
BottomSheetBehavior.STATE_EXPANDED ->
btBottomSheet.text = "Close Bottom Sheet"
BottomSheetBehavior.STATE_COLLAPSED ->
btBottomSheet.text = "Expand Bottom Sheet"
BottomSheetBehavior.STATE_DRAGGING -> {
}
BottomSheetBehavior.STATE_SETTLING -> {
}
}
}
override fun onSlide(bottomSheet: View, slideOffset: Float) {
}
})
btBottomSheet.setOnClickListener(View.OnClickListener {
expandCloseSheet()
})
btBottomSheetDialog.setOnClickListener(View.OnClickListener {
val view = layoutInflater.inflate(R.layout.bottom_sheet_dialog, null)
val dialog = BottomSheetDialog(this)
dialog.setContentView(view)
dialog.show()
})
}
private fun expandCloseSheet() {
if (sheetBehavior!!.state != BottomSheetBehavior.STATE_EXPANDED) {
sheetBehavior!!.state = BottomSheetBehavior.STATE_EXPANDED
btBottomSheet.text = "Close Bottom Sheet"
} else {
sheetBehavior!!.state = BottomSheetBehavior.STATE_COLLAPSED
btBottomSheet.text = "Expand Bottom Sheet"
}
}
}
Step 8. Now Run the application, in emulator or On you android device
Output screenshot Android Bottom Sheet example :
Video Output
Download source code Android BottomSheet in kotlin
Do comment if you have any doubt and suggestion on this tutorial.
Note : This example (Project) is developed in Android Studio 3.1.3 . Tested on Android 9 ( Android-P), compile SDK version API 27: Android 8.0 (Oreo)
MinSdkVersion=”15″
TargetSdkVersion=”27″
Coding in Kotlin