Factolize

Generate Android's Activity & Fragment's factory method that can pass arguments easily and safely.

Requirement

• Android 4.0.3 (API 15) or later

Install

Add the following gradle dependency exchanging x.x.x for the latest release.

Java

dependencies {
    implementation 'com.kazakago.factolize:factolize:x.x.x'
    annotationProcessor 'com.kazakago.factolize:factolize-processor:x.x.x'
}

Kotlin

apply plugin: 'kotlin-kapt'

dependencies {
    implementation 'com.kazakago.factolize:factolize:x.x.x'
    kapt 'com.kazakago.factolize:factolize-processor:x.x.x'
}

Usage

add @Factory　annotation to Activity / Fragment class you want to generate Factory method.
Also add @FactoryParam annotation to the field variable you want to specify as an argument.

@Factory // `@Factory` is nessesary to generate Factory class & method.
public class SubActivity extends Activity {

    @FactoryParam // `@FactoryParam` is nessesary to add factory method arguments.
    String param;

    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_sub);

        // This method assigns arguments to field variables.
        SubActivityFactory.injectArgument(this);
        
        System.out.print(param);　// print "your parameter."
    }

}

When building, [ACTIVITY_OR_FRAGMENT_NAME] + Factory class is auto generated based on the class with @Factory annotation.

public class MainActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        
        Button goToSubActivityButton = view.findViewById(R.id.goToSubActivityButton);
        goToSubActivityButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                // `SubActivityFactory` class is auto generated.
                Intent intent = SubActivityFactory.createIntent(getActivity(), "your parameter.");
                startActivity(intent);
            }
        });
    }

}

Refer to the sample module (Java & Kotlin) for details.

Advanced

Required flag & Overload factory method.

If you want to make an argument optional, you can make it arbitrary by describing @FactoryParam(requred = false). This default is true.

@Factory
public class SubActivity extends Activity {

    @FactoryParam
    String param1; //this parameter is required. (added @NonNull)
    @FactoryParam(required = true)
    String param2; //this parameter is required. (added @NonNull)
    @FactoryParam(required = false)
    String param3; //this parameter is optional. (added @Nullable)

}

If you specify @FactoryParam(required = false), an overloaded method will be added.

Intent intent = SubActivityFactory.createIntent(getActivity(), "parameter1", "parameter2", "parameter3"); // with optional argments
Intent intent = SubActivityFactory.createIntent(getActivity(), "parameter1", "parameter2"); // only required argments

Handling Activity / Fragment lifecycle & recreate behavior.

If you consider Andifid's Lifecycle, pass savedInstanceState to the injectArgment() method argument.
If this is specified, if Activity / Fragment recreates, it will not assign to the parameter.

In this case, implementing the saving process of the variable across the recreation of Activity / Fragment. More details.

@Factory
public class SubActivity extends Activity {

    @FactoryParam
    String param;

    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_sub);

        SubActivityFactory.injectArgument(this, savedInstanceState); // pass savedInstanceState
    }

}

This behavior is the same as the following code.

if (savedInstanceState == null) {
    SubActivityFactory.injectArgument(this);
}

Supported Type

• Interface
  • Parcelable
  • Serializable
• Interface[]
  • Parcelable[]
• Class
  • String
  • CharSequence
  • Size
  • SizeF
  • IBinder
  • Bundle
  • ArrayList<Integer>
  • ArrayList<String>
  • ArrayList<CharSequence>
  • ArrayList<Parcelable>
  • SparseArray<Parcelable>
• Class[]
  • String[]
  • CharSequence[]
• Primitive
  • Char
  • Byte
  • Short
  • Int
  • Long
  • Float
  • Double
  • Boolean
• Primitive[]
  • Char[]
  • Byte[]
  • Short[]
  • Int[]
  • Long[]
  • Float[]
  • Double[]
  • Boolean[]

This is the same as Android's Bundle specification. More details.

License

MIT License

Copyright (c) 2017 KazaKago

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.