MainActivity.java

package com.reactlibrary;

import android.content.Intent;
import android.net.Uri;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;

import com.facebook.react.bridge.ReactApplicationContext;
import com.github.hiteshsondhi88.libffmpeg.ExecuteBinaryResponseHandler;
import com.github.hiteshsondhi88.libffmpeg.FFmpeg;
import com.github.hiteshsondhi88.libffmpeg.exceptions.FFmpegCommandAlreadyRunningException;

public class MainActivity extends AppCompatActivity  {

    private ExecuteBinaryResponseHandler responseHandler = new ExecuteBinaryResponseHandler() {

        @Override
        public void onSuccess(String message) {
            super.onSuccess(message);
            Log.d(App.LOG, message);
            openGif();
        }

        @Override
        public void onProgress(String message) {
            super.onProgress(message);
            Log.d(App.LOG, message);
        }

        @Override
        public void onFailure(String message) {
            super.onFailure(message);
            Log.d(App.LOG, message);

        }

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

        @Override
        public void onFinish() {
            super.onFinish();
        }
    };

    public void convert() {
        FFmpeg ffmpeg = FFmpeg.getInstance(this);
        try {
            String command = "-y "
                    + "-i "
                    + App.VIDEO_FILE.getAbsolutePath()
                    + " "
                    + App.GIF_FILE.getAbsolutePath();


            ffmpeg.execute(command.split(" "), responseHandler);
        } catch (FFmpegCommandAlreadyRunningException e) {
            Log.e(App.LOG, e.getMessage());
        }
    }

    private  void openGif(){
        Intent intent = new Intent();
        intent.setAction(Intent.ACTION_VIEW);
        intent.setDataAndType(Uri.fromFile(App.GIF_FILE), "image/*");
        startActivity(intent);
    }


    private final ReactApplicationContext reactContext;

    public MainActivity(ReactApplicationContext reactContext) {
        super(reactContext);
        this.reactContext = reactContext;
        convert();
    }

    @Override
    public String getName() {
        return "RNGifMaker";
    }
}