Fast scroller alphabet

This is an Open Source Android library that allows developers to easily add fast scroller alphabet to recycler view. Feel free to use it all you want in your Android apps provided that you cite this project and include the license in your app. Support Sdk Version 14 to lastest.

Version

• 1.2.0: Add textColor, textSelectedColor, backgroundColor, backgroundBorderColor options.
• 1.1.0: Fix WRAP_CONTENT on Android Support Library 23.2.0 and wrong alphabet item selection in long alphabet list item.
• 1.0.0: Just work good on RecyclerView support version 23.0.1 and short alphabet list item.

Feature

• Change TextColor: just add <color name="alphabet_text_color">#3F51B5</color> into colors.xml.
• Change TextSelectedColor: just add <color name="alphabet_text_selected_color">#3F51B5</color> into colors.xml.
• Change BackgroundColor: just add <color name="alphabet_background_color">#3F51B5</color> into colors.xml.
• Change BackgroundBorderColor: just add <color name="alphabet_background_border_color">#3F51B5</color> into colors.xml.
• Change FastScrollerAlphabet width: just add <dimen name="alphabet_width">30dp</dimen> into dimens.xml, currently is 30dp.
• Change FastScrollerAlphabet Text Size: just add <dimen name="font_medium">15sp</dimen> into dimens.xml, currently is 15sp.

Dependency

repositories {
    maven { url 'https://oss.sonatype.org/content/groups/public' }
}

dependencies {
    compile 'com.github.viethoa:fastscroller:1.2.0'
}

**Or**:

Download this project and import library in there.

How to use

Step 1: add this to your xml:

<com.viethoa.RecyclerViewFastScroller
        android:id="@+id/fast_scroller"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:layout_alignParentEnd="true"
        android:layout_alignParentRight="true"/>

Step 2: set recycler view for RecyclerViewFastscroller.

fastScroller.setRecyclerView(mRecyclerView);

Step 3: generate alphabet item:

ArrayList<AlphabetItem> mAlphabetItems = new ArrayList<>();
List<String> strAlphabets = new ArrayList<>();
for (int i = 0; i < mDataArray.size(); i++) {
    String name = mDataArray.get(i);
    if (name == null || name.trim().isEmpty())
        continue;

    String word = name.substring(0, 1);
    if (!strAlphabets.contains(word)) {
        strAlphabets.add(word);
        mAlphabetItems.add(new AlphabetItem(i, word, false));
    }
}

fastScroller.setUpAlphabet(mAlphabetItems);

Note: mDataArray: this is your recycler data array model, just get the name you want to fast scroll.

Step 4: implement bubble text getter listener in your RecyclerViewAdapter:

implements RecyclerViewFastScroller.BubbleTextGetter

@Override
public String getTextToShowInBubble(int position) {
    if (pos < 0 || pos >= mDataArray.size())
        return null;

    String name = mDataArray.get(pos);
    if (name == null || name.length() < 1)
        return null;

    return mDataArray.get(pos).substring(0, 1);
}

Note: This function to mapping your RecyclerView with FastScroller alphabet in scrolling.

License

Copyright 2015 Khuat Viet Hoa

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.