DictionaryHeadService.java

package com.madeinhk.english_chinesedictionary.service;

import android.app.Service;
import android.content.Context;
import android.content.Intent;
import android.graphics.PixelFormat;
import android.os.Handler;
import android.os.IBinder;
import android.view.Gravity;
import android.view.LayoutInflater;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewConfiguration;
import android.view.WindowManager;
import android.widget.CompoundButton;
import android.widget.TextView;
import android.widget.ToggleButton;

import com.madeinhk.english_chinesedictionary.DictionaryActivity;
import com.madeinhk.english_chinesedictionary.R;
import com.madeinhk.model.Favourite;
import com.madeinhk.model.Word;
import com.madeinhk.utils.Analytics;

public class DictionaryHeadService extends Service {

    private WindowManager mWindowManager;
    private View mDictionaryHead;
    private TextView mTextView;
    private Word mWord;
    private ToggleButton mFavButton;
    private Handler mHandler;
    private static final String KEY_WORD = "key_word";

    @Override
    public IBinder onBind(Intent intent) {
        // Not used
        return null;
    }

    @Override
    public void onCreate() {
        super.onCreate();
        mHandler = new Handler();
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        super.onStartCommand(intent, flags, startId);
        Analytics.trackPopup(this);
        mWord = intent.getParcelableExtra(KEY_WORD);
        if (mDictionaryHead == null) {
            LayoutInflater inflate = (LayoutInflater)
                    this.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            mDictionaryHead = inflate.inflate(R.layout.dictionary_head, null);
            mTextView = (TextView) mDictionaryHead.findViewById(R.id.message);
            mFavButton = (ToggleButton) mDictionaryHead.findViewById(R.id.fav_button);

            mWindowManager = (WindowManager) getSystemService(WINDOW_SERVICE);
            final WindowManager.LayoutParams params = new WindowManager.LayoutParams(
                    WindowManager.LayoutParams.WRAP_CONTENT,
                    WindowManager.LayoutParams.WRAP_CONTENT,
                    WindowManager.LayoutParams.TYPE_SYSTEM_ALERT,
                    WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE |
                            WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS,
                    PixelFormat.TRANSLUCENT);
            params.windowAnimations = android.R.style.Animation_Toast;
            params.gravity = Gravity.BOTTOM | Gravity.CENTER_HORIZONTAL;
            params.x = 0;
            params.y = 100;
            mWindowManager.addView(mDictionaryHead, params);

            mDictionaryHead.setOnTouchListener(new View.OnTouchListener() {
                private int initialX;
                private int initialY;
                private float initialTouchX;
                private float initialTouchY;
                private boolean mAlwaysInTapRegion = true;
                final ViewConfiguration configuration =
                        ViewConfiguration.get(DictionaryHeadService.this);
                final int touchSlop = configuration.getScaledTouchSlop();
                private int mTouchSlopSquare = touchSlop * touchSlop;

                @Override
                public boolean onTouch(View v, MotionEvent event) {
                    restartDismissTimer();
                    switch (event.getAction()) {
                        case MotionEvent.ACTION_DOWN:
                            initialX = params.x;
                            initialY = params.y;
                            initialTouchX = event.getRawX();
                            initialTouchY = event.getRawY();
                            mAlwaysInTapRegion = true;
                            return true;
                        case MotionEvent.ACTION_UP:
                            if (mAlwaysInTapRegion) {
                                Intent intent = DictionaryActivity
                                        .getIntent(DictionaryHeadService.this, mWord.mWord);
                                intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
                                startActivity(intent);
                                mHandler.removeCallbacksAndMessages(null);
                                stopSelf();
                            }
                            return true;
                        case MotionEvent.ACTION_CANCEL:
                            mAlwaysInTapRegion = false;
                        case MotionEvent.ACTION_MOVE:
                            final int deltaX = (int) (event.getRawX() - initialTouchX);
                            final int deltaY = (int) (event.getRawY() - initialTouchY);
                            final int distance = (deltaX * deltaX) + (deltaY * deltaY);
                            if (distance > mTouchSlopSquare) {
                                mAlwaysInTapRegion = false;
                            }
                            params.x = initialX + (int) (event.getRawX() - initialTouchX);
                            params.y = initialY - (int) (event.getRawY() - initialTouchY);
                            mWindowManager.updateViewLayout(mDictionaryHead, params);
                            return true;
                    }
                    return false;
                }
            });
        }
        StringBuilder sb = new StringBuilder();
        if (mWord.mDifficulty > 0) {
            sb.append(this.getString(R.string.word_frequency)).append(" ");
            int commonness = 5 - mWord.mDifficulty;
            for (int i = 0; i < 5; i++) {
                if (i <= commonness) {
                    sb.append('★');
                } else {
                    sb.append('☆');
                }
            }
            sb.append("\n");
        }
        sb.append(mWord.buildMeaningSummary());
        mTextView.setText(sb.toString());


        final Favourite favourite = Favourite.fromWord(mWord);
        boolean alreadyMarked = favourite.isExists(this);
        mFavButton.setChecked(alreadyMarked);

        mFavButton.setOnCheckedChangeListener(
                new CompoundButton.OnCheckedChangeListener() {
                    @Override
                    public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
                        if (isChecked) {
                            favourite.save(DictionaryHeadService.this);
                        } else {
                            favourite.delete(DictionaryHeadService.this);
                        }
                    }
                });
        restartDismissTimer();

        return START_NOT_STICKY;
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
        removeView();
    }

    private void restartDismissTimer() {
        mHandler.removeCallbacksAndMessages(null);
        mHandler.postDelayed(new Runnable() {
            @Override
            public void run() {
                stopSelf();
            }
        }, 5000);
    }

    private void removeView() {
        if (mDictionaryHead != null) {
            mWindowManager.removeView(mDictionaryHead);
        }
    }

    public static void show(Context context, Word word) {
        Intent intent = new Intent(context, DictionaryHeadService.class);
        intent.putExtra(KEY_WORD, word);
        context.startService(intent);
    }

}