Attention

I'm not going to support this anymore. Just use a better solution, e.g. this one Indefinite-Pager-Indicator

BubblePagerIndicator

A view pager indicator view to deal with a large amount of pages. Nice scale and transition animations are supported.

Usage

1. Add mavenCentral() to repositories block in your gradle file.
2. Add implementation 'com.github.shuhart:bubblepagerindicator:1.2.0' to your dependencies.
3. Add BubblePageIndicator into your layouts or view hierarchy:

<com.shuhart.bubblepagerindicator.BubblePageIndicator
    android:id="@+id/indicator"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_below="@id/pager"
    android:layout_centerHorizontal="true"
    android:layout_marginBottom="32dp"
    android:layout_marginTop="32dp"
    app:bpi_fillColor="@color/colorAccent"
    app:bpi_pageColor="@color/colorPrimary"
    app:bpi_radius="8dp"
    app:bpi_marginBetweenCircles="6dp"
    app:bpi_onSurfaceCount="@integer/default_bubble_indicator_on_surface_count"
    app:bpi_risingCount="@integer/default_bubble_indicator_rising_count"/>

4. Attach indicator to the ViewPager instance:

pager = findViewById(R.id.pager);
indicator = findViewById(R.id.indicator);
adapter = new ViewPagerAdapter();
pager.setAdapter(adapter);
indicator.setViewPager(pager);

An adapter should be attached to the ViewPager before calling indicator.setViewPager(pager).

5. You can customize the behavior in runtime:

indicator.setOnSurfaceCount(3);
indicator.setRisingCount(2);
// resolved color
indicator.setFillColor(ContextCompat.getColor(this, R.color.colorAccent));
// resolved color
indicator.setPageColor(ContextCompat.getColor(this, R.color.colorPrimary));
// in px
indicator.setRadius(getResources().getDimensionPixelSize(R.dimen.default_bubble_indicator_radius));
// in px
indicator.setMarginBetweenCircles(getResources().getDimensionPixelSize(
            R.dimen.default_bubble_indicator_circles_margin));

Customization

Attribute	Description	Default Value
bpi_pageColor	Current page circle color.	#FFFFFF
bpi_fillColor	Circles color	#000000
bpi_radius	Normal circle radius.	3dp
bpi_marginBetweenCircles	Margin between centers of circles.	3dp
bpi_onSurfaceCount	A number of circles with full radius (bpi_radius)	5
bpi_risingCount	A number of scaled circles.	2

Maximum number of circles visible to the user is bpi_onSurfaceCount + bpi_risingCount * 2 (Default is 9).
At the beginning only bpi_onSurfaceCount + bpi_risingCount (Default is 7) circles are visible.
Radius for a rising circle is scaled by power of 2 with some correction applied.
In every aspect the library is mimicking the Instagram indicator behavior.

Special thanks

@tree1891 for his help in fixing many annoying issues.

License

Copyright 2017 Bogdan Kornev.

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.