Android MultiAutoComplete

A library that provides a layer of abstraction over the Android MultiAutoCompleteTextView standard component, to simplify showing a drop down menu with suggestions for auto complete when the user is typing into an editable text view.

• Built-in support for multiple data types in the same MultiAutoCompleteTextView
• Built-in support for different token types: prefix handles (i.e. @johndoe) or comma-separated values
• Built-in support for a simple image/text data type with standard layout
• Fully customizable item layout management, view binders and view holders included
• Fully customizable data filtering strategy and data sorting policies
• Type-specific listeners to detect when a full token is added/removed from the text
• High performance data indexing on a background thread to reduce filtering overhead

Using MultiAutoComplete can be as easy as this:

    List<SimpleItem> itemsList = ...
    MultiAutoComplete autoComplete = MultiAutoComplete.Build.from(itemsList);
    autoComplete.onViewAttached(autoCompleteEditText);

Advantages over using MultiAutoCompleteTextView directly

• No need to write your own Tokenizer implementation for handles
• No need to write the drop down ListView adapter boilerplate code
• No need to write a (thread-safe) Filter subclass for the adapter
• No need to write an adapter composition pattern to support multiple types
• No need to write decorator objects to merge different data types in a single adapter
• Support for the hidden Android API Filter$Delayer through reflection (new in 0.2.5)
• (coming soon) Ability to easily swap between AutoCompleteTextView and MultiAutoCompleteTextView

Download

Due to the announced shutdown of JCenter this library has been migrated to Maven Central repository. At the same time its Group ID has been changed from com.teamwork to com.teamwork.multiautocomplete.

Add dependency via Gradle: In your project's build.gradle:

allprojects {
  repositories {
      mavenCentral()
      ...
  }
  ...
}

then in the module's build.gradle:

dependencies {
    implementation 'com.teamwork.multiautocomplete:android-multiautocomplete:0.4.0'
}

or Maven:

<dependency>
  <groupId>com.teamwork.multiautocomplete</groupId>
  <artifactId>android-multiautocomplete</artifactId>
  <version>0.4.0</version>
  <type>pom</type>
</dependency>

Previous versions of the library can still be found on Bintray (complete shutdown is planned on February 2022).

Add dependency via Gradle (please note the different groupId):

compile 'com.teamwork:android-multiautocomplete:0.3.0'

or Maven:

<dependency>
  <groupId>com.teamwork</groupId>
  <artifactId>android-multiautocomplete</artifactId>
  <version>0.3.0</version>
  <type>pom</type>
</dependency>

Documentation

Javadoc documentation is available here: https://teamwork.github.io/android-multiautocomplete/

Domain language

To understand how to use the library quickly, keep in mind the definition of those recurring words in the API:

• Type adapter: Just like Android adapters (and the Adapter design pattern), a type adapter is used to display and filter a single data type (also called model). Each model requires a separate type adapter.

• Token: A text token is a string that is processed by a filter and recognized as valid for triggering auto completion. A token can be prefixed by a char handle (i.e. @johndoe, where '@' is the handle) or can be a single word with a separator (i.e. a space, or a comma).

• Constraint: a text constraint is similar to a token, but it's used to filter contents from the type adapters. If the token has a handle, i.e. @johndoe, its constraint will be johndoe.

Components

In order to customize MultiAutoComplete to suit your needs, you're going to need to use or implement some or all of these interfaces:

• MultiAutoComplete: The main library component, it manages the type adapters and holds a reference to the MultiAutoCompleteTextView. It provides lifecycle methods to attach/detach the view itself. It holds an "adapter of adapters" internally, with which the presenter can handle multiple data types in the same instance and decide which adapter to use for filtering depending on what kind of token is being typed in.

To create an instance use one of the static factory methods in MultiAutoComplete.Builder or, for full customization, use the Builder itself:

    MultiAutoComplete autoComplete = new MultiAutoComplete.Builder()
        .tokenizer(tokenizer)
        .addTypeAdapter(typeAdapter1)
        .addTypeAdapter(typeAdapter2)
        .build();

• AutoCompleteTypeAdapter: A typed adapter, used to provide a layout, data binding and filter options for a single data type. It holds a ViewBinder and a TokenFilter.

To create an instance use the static factory method AutoCompleteTypeAdapter.Build.from():

        AutoCompleteViewBinder<MyDataType> viewBinder = new MyViewBinder();
        TokenFilter<MyDataType> tokenFilter = new MyTokenFilter();
        AutoCompleteTypeAdapter<MyDataType> myTypeAdapter = AutoCompleteTypeAdapter.Build.from(viewBinder, tokenFilter);

To set (or replace) the items for the type adapter, even after MultiAutoComplete was created, just call:

        List<MyDataType> myItemsList = ...
        myTypeAdapter.setItems(myItemsList);

• AutoCompleteViewBinder: A typed component used by a type adapter to bind the data from an item to the appropriate layout. SimpleItemViewBinder is a concrete implementation provided for the SimpleItem data type.

• TokenFilter: A typed component used by a type adapter that takes care of the filtering strategy for the adapter elements. It also determines whether the type adapter supports the text token that's being currently typed in. Concrete implementations for basic usage are HandleTokenFilter, which support a single handle prefix (like '@'), and SimpleTokenFilter, which just matches any token. Both filter items by matching the current text constraint with the value returned by the item's toString() method.

• Tokenizer: Defined by the MultiAutoCompleteTextView.Tokenizer interface (see javadoc), a tokenizer is used by a MultiAutoCompleteTextView to detect the beginning and ending of a token within a text sequence. Using PrefixTokenizer allows you to match all tokens with a handle which are supported by the type adapters you provide:

        MultiAutoCompleteTextView.Tokenizer tokenizer = new PrefixTokenizer('@',':');

Alternatively, you can use the Android built-in MultiAutoCompleteTextView.CommaTokenizer (see javadoc) to detect comma-separated words or write your own Tokenizer for full customization of the token detection, including which characters and separators to support.

Class diagram

Demo App

The module demo contains simple usage examples of MultiAutoComplete. Pull the source code and run the app to check it out.

License

Copyright 2017-2021 Teamwork.com

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.