Rainbow

A fork of Processing for Android

Guide

• What can I do with Rainbow?

With Rainbow you can easily draw graphics (interactive or not) in your Android application.

• How to do it?

Import it on your build.gradle

repositories {
    maven {
	    url "https://jitpack.io"
    }
}

dependencies {
    compile 'com.github.juankysoriano:rainbow:v1.0.0-rc5'
}

Once done it is very easy to integrate! Just extend Rainbow and attach it to one of your ViewGroup! Then you will @Override the methods in the RainbowLifeCycleCallback to control your animations. (Check the demo app!!)

Something like this:

1 ) Creating a Rainbow object:

public class RainbowSketch extends Rainbow {

    private static final int FRAME_RATE = 60;
    protected RainbowSketch(ViewGroup parentView) {
        super(parentView);
    }

    public void onSketchSetup() {
      //Called when the rainbow is being setup.
      frameRate(FRAME_RATE);
    }

    public void onDrawingStart() {
      //Called when the rainbow sketch is about to start.
    }

    public void onDrawingResume() {
       //Called when the rainbow sketch is resumed
    }

    public void onDrawingStep() {
       //Called when the rainbow sketch is about to perform a new step
       //Here is where the animations should be done.
       
       //This will be called a FRAME_RATE number of times per second!!! 
       //GREAT and ASYNCHRONOUS!!
    }

    public void onDrawingPause() {
       //Called when the rainbow sketch is about to pause
    }

    public void onDrawingStop() {
        //Called when the rainbow sketch is about to stop
    }

    public void onSketchDestroy() {
        //Called when the rainbow sketch is about to be destroyed
    }
}

2 ) What is a RainbowDrawer?

A RainbowDrawer exposes to you all the methods you will need in order to do amazing drawings. Following one example.

    public void onDrawingStep() {
       //Let's retrieve a RainbowDrawer object (for painting).
       RainbowDrawer rainbowDrawer = getRainbowDrawer();
        
       //Let's setup our paint-style
       rainbowDrawer.fill(Color.RED);
       rainbowDrawer.strokeWeight(2);
       rainbowDrawer.stroke(Color.BLUE);
       
       //Let's paint something!
       
       // A quarter screen rectangle
       rainbowDrawer.rect(0, 
                          0, 
                          getWidth()/2, 
                          getHeight()/2); 
       
       // A quarter screen ellipse
       rainbowDrawer.ellipse(getWidth()/2, 
                            getHeight()/2, 
                            getWidth()/2, 
                            getHeight()/2);  
    }

Try to compilate it a bit!

3 ) What is a RainbowInputController ?

With RainbowInputController you have access to the user interactions with your Rainbow

    public void onDrawingStep() {
        //Let's retrieve a RainbowDrawer object (for painting).
        RainbowDrawer rainbowDrawer = getRainbowDrawer();
        //Let's setup our paint-style
        rainbowDrawer.fill(Color.RED);
        rainbowDrawer.strokeWeight(2);
        rainbowDrawer.stroke(Color.BLUE);
       
        //Lets's retrieve a RainbowInputController (for controlling). 
        RainbowInputController rainbowInputController = getRainbowInputController();
        //Let's paint something
        rainbowDrawer.ellipse(rainbowInputController.getX(), 
                            rainbowInputController.getY(), 
                            100, 
       	                    100);
    }

You can also register to it a RainbowInteractionListener for more fine grained control over the user interactions.

public interface RainbowInteractionListener {
    void onSketchTouched(final MotionEvent event, 
                        final RainbowDrawer rainbowDrawer);

    void onSketchReleased(final MotionEvent event, 
                        final RainbowDrawer rainbowDrawer);

    void onFingerDragged(final MotionEvent event, 
                        final RainbowDrawer rainbowDrawer);

    void onMotionEvent(final MotionEvent event, 
                        final RainbowDrawer rainbowDrawer);
}

4 . Let's inject a Rainbow into your ViewGroup

public class SketchActivity extends Activity {

    private RainbowSketch sketch;
    private ViewGroup sketchView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.sketch);
        sketchView = getSketchView();
        sketch = new RainbowSketch(sketchView);
    }

    private ViewGroup getSketchView() {
        return (ViewGroup) findViewById(R.id.rainbow_layout);
    }

    @Override
    public void onPause() {
        sketch.pause();
        super.onPause();
    }

    @Override
    public void onStart() {
        super.onStart();
        sketch.start();
    }

    @Override
    public void onResume() {
        super.onResume();
        sketch.resume();
    }

    @Override
    public void onStop() {
        sketch.stop();
        super.onStop();
    }

    @Override
    public void onDestroy() {
        sketch.destroy();
        sketch = null;
        super.onDestroy();
    }

Proguard

As rainbow uses third party libraries for now you would have to include this into your proguard properties:

-dontwarn com.squareup.picasso.**
-dontwarn com.squareup.okhttp.**

License

Copyright 2014 Juanky Soriano Ltd.

This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2 of the License, or (at your option) any later version.

This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program.  If not, see <http://www.gnu.org/licenses/>.