Fragment Creator

Fragment Creator is a code generation library to manage fragment class creation and arguments for Android.

I wrote the newInstance method every time when declaring a new Fragment. Then, call Fragment#getArguments() and call a get method that is adapted parameter type (ex. getString(), getParcelable()). It's so a boring boilerplate code.

This library helps you to manage fragment class creation and arguments.

How to use

Annotate the arguments of Fragment

@FragmentCreator public class MainFragment extends Fragment {

@Args
  String keyword;

@Args(require = false)
  String userId; 
}

Then, MainFragmentCreator is generated.

Create fragment with the FragmentCreator

MainFragment instance = MainFragmentCreator

  .newBuilder("keyword")

  .build();
  MainFragment instance = MainFragmentCreator

  .newBuilder("keyword")  // required

  .setUserId("mike")

// optional

  .build();

Read the arguments with the FragmentCreator

public MainFragment extends Fragment {

@Args
  String keyword;

@Args(require = false)
  String userId;

@Override
  public void onCreate(@Nullable Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

MainFragmentCreator.read(this);

 // this.keyword, this.userId are initialized.
  
}
 
}

Default value

You can set default value.

public MainFragment extends Fragment {

// The default value can be set only if the argument is optional.
  @Args(require = false, defaultString = "unknown")
  String keyword;

@Args(require = false, defaultInt = -1)
  int userId;  
}

Supported types

• primitive type
• java.lang.String
• java.lang.Boolean
• java.lang.Byte
• java.lang.Character
• java.lang.Short
• java.lang.Integer
• java.lang.Long
• java.lang.Float
• java.lang.Double

Private field

You should declare a setter method if using private field.

public MainFragment extends Fragment {

@Args
  String keyword;

@Args(require = false)
  private String userId;

public String setUserId(String userId){

this.userId = userId;
  
}
 
}

Type Serializer

If you want to use the class such as the following, you can use the ArgsSerializer.

// It is not Serializable or Parcelable. public class Product {

public int id;

public String name; 
}

At first, define a class that implements the ArgsSerializer.

public class StringSerializer implements ArgsSerializer<Product, String> {

@Override
  public String serialize(Product product) {

return product.getId() + "," + product.getName();

  
}

@Override
  public Product deserialize(String str) {

String[] split = str.split(",");

Product product = new Product();

product.setId(Integer.parseInt(split[0]));

product.setName(split[1]);

return product;
  
}
 
}

Set @Serializer.

@FragmentCreator public class MainFragment extends Fragment {

  @Args
  @Serializer(to = String.class, serializer = StringSerializer.class)
  Product product; //...

Supported types

• primitive type
• java.lang.String
• java.lang.Boolean
• java.lang.Byte
• java.lang.Character
• java.lang.Short
• java.lang.Integer
• java.lang.Long
• java.lang.Float
• java.lang.Double
• java.lang.CharSequence
• android.os.Parcelable
• java.io.Serializable
• java.util.ArrayList<? extends android.os.Parcelable>
• java.util.ArrayList<java.lang.Integer>
• java.util.ArrayList<java.lang.String>
• java.util.ArrayList<java.lang.CharSequence>

Not supported yet

• android.os.Parcelable[]
• android.util.SparseArray<? extends android.os.Parcelable>
• boolean[]
• byte[]
• short[]
• char[]
• int[]
• long[]
• float[]
• double[]
• java.lang.String[]
• java.lang.CharSequence[]
• android.os.Bundle

Installation

This library is distributed by JitPack. Add dependencies your build.gradle

apt 'com.github.sys1yagi.fragment-creator:processor:0.8.1' compile 'com.github.sys1yagi.fragment-creator:library:0.8.1' 

Development

Show version

$ ./gradlew version 

Bump version

$ ./gradlew bumpMajor $ ./gradlew bumpMinor $ ./gradlew bumpPatch 

Generate README

$ ./gradlew genReadMe