Code Snippet to create Google Space like navigation tab in Android

FabTabBackgroundView.java

public final class FabTabBackgroundView extends View {

    Paint paint;
    Path path;

    @TargetApi(Build.VERSION_CODES.LOLLIPOP)
    public FabTabBackgroundView(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
        super(context, attrs, defStyleAttr, defStyleRes);
        init();
    }

    public FabTabBackgroundView(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        init();
    }

    public FabTabBackgroundView(Context context, AttributeSet attrs) {
        super(context, attrs);
        init();
    }

    public FabTabBackgroundView(Context context) {
        super(context);
        init();
    }

    void init() {
        paint = new Paint();
        Resources localResources = getContext().getResources();
        paint.setStyle(Paint.Style.FILL_AND_STROKE);
        paint.setAntiAlias(true);
        paint.setColor(localResources.getColor(R.color.tab));
        paint.setAlpha(244);
    }

    @Override
    protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
        super.onLayout(changed, left, top, right, bottom);
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
        Resources localResources = getContext().getResources();
        int width = View.MeasureSpec.getSize(widthMeasureSpec);
        int offset = localResources.getDimensionPixelOffset(R.dimen.offset);
        int size = localResources.getDimensionPixelSize(R.dimen.size);
        int j = size + 2 * offset;
        int k = (int) (0.7D * j);
        int m = width / 2 - size;
        int n = width - m;
        int i1 = j - k;
        path = new Path();
        path.reset();
        path.moveTo(0.0F, i1);
        path.lineTo(m, i1);
        //System.out.println("width-->" + width + "offset--->" + offset + "size-->" + size + "j-->" + j + "k-->" + k + "m--->" + m + "n-->" + n + "il--->" + i1);
        //System.out.println();
        path.cubicTo(m + size / 2, i1, (width - size) / 2, 0.0F, width / 2, 0.0F);
        path.cubicTo((width + size) / 2, 0.0F, n - size / 2, i1, n, i1);
        path.lineTo(width, i1);
        path.lineTo(width, j);
        path.lineTo(0.0F, j);
        path.close(); /*the anchors you want, the curve will tend to reach these anchor points; look at the wikipedia article to understand more */
        this.setMeasuredDimension(width, j);
    }

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        canvas.drawPath(path, paint);
    }

    @Override
    protected boolean awakenScrollBars() {
        return super.awakenScrollBars();
    }

    @Override
    protected boolean awakenScrollBars(int startDelay) {
        return super.awakenScrollBars(startDelay);
    }

    @Override
    protected boolean awakenScrollBars(int startDelay, boolean invalidate) {
        return super.awakenScrollBars(startDelay, invalidate);
    }

    @Override
    protected boolean dispatchGenericFocusedEvent(MotionEvent event) {
        return super.dispatchGenericFocusedEvent(event);
    }

    @Override
    protected boolean dispatchGenericPointerEvent(MotionEvent event) {
        return super.dispatchGenericPointerEvent(event);
    }

    @Override
    protected boolean dispatchHoverEvent(MotionEvent event) {
        return super.dispatchHoverEvent(event);
    }


}

navigation_tab.xml

<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:id="@+id/fL"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_gravity="bottom"
    android:clickable="true"
    app:layout_behavior="solutions.epictech.www.epicresearchapp.controller.FloatingActionButtonBehavior">

    <FabTabBackgroundView
        android:id="@+id/fabTab"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_gravity="bottom" />

    <android.support.design.widget.FloatingActionButton
        android:id="@+id/fab"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="bottom|center_horizontal"
        android:layout_marginBottom="10dp"
        android:clickable="true"
        android:src="@drawable/ic_card_giftcard_white_24dp"
        app:borderWidth="0.0dip"
        app:fabSize="normal" />

    <RadioGroup
        android:id="@+id/navGroup"
        android:layout_width="match_parent"
        android:layout_height="70dp"
        android:layout_gravity="bottom"
        android:orientation="horizontal">

        <RadioButton
            android:id="@+id/homeTab"
            android:layout_width="0dp"
            android:layout_height="match_parent"
            android:layout_gravity="center_horizontal|center_vertical"
            android:layout_marginTop="10dp"
            android:layout_weight="1"
            android:button="@null"
            android:drawableLeft="@drawable/home_icon"
            android:gravity="center_horizontal|center_vertical"
            android:paddingLeft="@dimen/leftnav_tab_padding_left"
            android:paddingRight="@dimen/leftnav_tab_padding_left"
            android:text="HOME"
            android:textAlignment="gravity"

            android:textColor="@color/radio_btn"
            android:textSize="13dp"
            android:typeface="sans" />

        <RadioButton
            android:id="@+id/serviceTab"
            android:layout_width="0dp"
            android:layout_height="match_parent"
            android:layout_gravity="center_horizontal|center_vertical"
            android:layout_marginLeft="100dp"
            android:layout_marginTop="10dp"
            android:layout_weight="1"
            android:button="@null"
            android:drawableLeft="@drawable/service_icon"
            android:gravity="center_horizontal|center_vertical"
            android:paddingLeft="@dimen/rightnav_tab_padding_left"
            android:paddingRight="@dimen/rightnav_tab_padding_left"
            android:text="SERVICES"
            android:textAlignment="gravity"

            android:textColor="@color/radio_btn"
            android:textSize="13dp"
            android:typeface="sans" />
    </RadioGroup>
</FrameLayout>

Thankyou so much for this!!! I've been trying for this for months, and thanks to you, I can finally implement it! :D 👍 💯

Welcome :)