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Floating Action Button

Floating action button Mini

From Google material design documentation.

A floating action button represents the primary action in an application. A floating action button is used for a promoted action.

Shaped like a circled icon floating above the UI, it changes color upon focus and lifts upon selection. When pressed, it may contain more related actions.

How to add?

I. In your build.gradle, add latest appcompat and design libraries.

dependencies {  
    compile 'com.android.support:appcompat-v7:X.X.X' // where X.X.X version
    compile 'com.android.support:design:X.X.X' // where X.X.X version
}

II. Make your activity extend android.support.v7.app.AppCompatActivity.

public class MainActivity extends AppCompatActivity {  
    ...
}

III. Declare your FloatingActionButton inside any layout.xml file.

<android.support.design.widget.FloatingActionButton
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:src="@drawable/ic_call" />

How to style

Floating action button Mini

Background color

I. Declare custom style in your values/styles.xml file.

<style name="MyFloatingButton" parent="Theme.AppCompat.Light">
    <item name="colorAccent">@color/pink</item>
</style>

II. Apply this style to your FloatingActionButton via android:theme attribute.

<android.support.design.widget.FloatingActionButton
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:src="@drawable/ic_call"
    android:theme="@style/MyFloatingButton" />

Ripple color

To change the color for the ripple effects when FloatingActionButton is pressed use app:rippleColor attribute.

<android.support.design.widget.FloatingActionButton
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:src="@drawable/ic_call"
    app:rippleColor="@color/indigo" />

Icon

To change FloatingActionButton icon use android:src attribute.

<android.support.design.widget.FloatingActionButton
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:src="@drawable/ic_favorite"/>

Size

Floating action buttons come in two sizes: - Default size: For most use cases - Mini size: Only used to create visual continuity with other screen elements

To change FloatingActionButton size use app:fabSize attribute with one of pre-defined constant values: mini or normal.

<android.support.design.widget.FloatingActionButton
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:src="@drawable/ic_mini"
    app:fabSize="mini"/>