FloatingActionButton.java

/**
 * Odoo, Open Source Management Solution
 * Copyright (C) 2012-today Odoo SA (<http:www.odoo.com>)
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version
 *
 * This program 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 Affero General Public License for more details
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <http:www.gnu.org/licenses/>
 *
 * Created on 9/1/15 2:25 PM
 */
package odoo.controls.fab;

import android.animation.ObjectAnimator;
import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Point;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;
import android.util.AttributeSet;
import android.view.Display;
import android.view.MotionEvent;
import android.view.View;
import android.view.WindowManager;
import android.view.animation.AccelerateDecelerateInterpolator;
import android.view.animation.Interpolator;
import android.widget.AbsListView;

import com.odoo.R;

public class FloatingActionButton extends View {
    public static final String TAG = FloatingActionButton.class.getSimpleName();
    private final Interpolator mInterpolator = new AccelerateDecelerateInterpolator();
    private final Paint mButtonPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
    private final Paint mDrawablePaint = new Paint(Paint.ANTI_ALIAS_FLAG);
    private Bitmap mBitmap;
    private int mColor;
    private boolean mHidden = false;
    /**
     * The FAB button's Y position when it is displayed.
     */
    private float mYDisplayed = -1;
    /**
     * The FAB button's Y position when it is hidden.
     */
    private float mYHidden = -1;

    public FloatingActionButton(Context context) {
        this(context, null);
    }

    public FloatingActionButton(Context context, AttributeSet attributeSet) {
        this(context, attributeSet, 0);
    }

    public FloatingActionButton(Context context, AttributeSet attrs,
                                int defStyleAttr) {
        super(context, attrs, defStyleAttr);

        TypedArray a = getContext().obtainStyledAttributes(attrs,
                R.styleable.FloatingActionButton);
        mColor = a.getColor(R.styleable.FloatingActionButton_fabColor,
                Color.WHITE);
        mButtonPaint.setStyle(Paint.Style.FILL);
        mButtonPaint.setColor(mColor);
        float radius, dx, dy;
        radius = a.getFloat(R.styleable.FloatingActionButton_shadowRadius,
                10.0f);
        dx = a.getFloat(R.styleable.FloatingActionButton_shadowDx, 0.0f);
        dy = a.getFloat(R.styleable.FloatingActionButton_shadowDy, 3.5f);
        int color = a.getInteger(R.styleable.FloatingActionButton_shadowColor,
                Color.argb(100, 0, 0, 0));
        mButtonPaint.setShadowLayer(radius, dx, dy, color);

        Drawable drawable = a
                .getDrawable(R.styleable.FloatingActionButton_drawable);
        if (null != drawable) {
            mBitmap = ((BitmapDrawable) drawable).getBitmap();
        }
        setWillNotDraw(false);
        setLayerType(View.LAYER_TYPE_SOFTWARE, null);

        WindowManager mWindowManager = (WindowManager) context
                .getSystemService(Context.WINDOW_SERVICE);
        Display display = mWindowManager.getDefaultDisplay();
        Point size = new Point();
        display.getSize(size);
        mYHidden = size.y;
        a.recycle();
    }

    public void setColor(int color) {
        mColor = color;
        mButtonPaint.setColor(mColor);
        invalidate();
    }

    public void setDrawable(Drawable drawable) {
        mBitmap = ((BitmapDrawable) drawable).getBitmap();
        invalidate();
    }

    @Override
    protected void onDraw(Canvas canvas) {
        canvas.drawCircle(getWidth() / 2, getHeight() / 2,
                (float) (getWidth() / 2.6), mButtonPaint);
        if (null != mBitmap) {
            canvas.drawBitmap(mBitmap, (getWidth() - mBitmap.getWidth()) / 2,
                    (getHeight() - mBitmap.getHeight()) / 2, mDrawablePaint);
        }
    }

    @Override
    protected void onLayout(boolean changed, int left, int top, int right,
                            int bottom) {
        // Perform the default behavior
        super.onLayout(changed, left, top, right, bottom);

        // Store the FAB button's displayed Y position if we are not already
        // aware of it
        if (mYDisplayed == -1) {
            mYDisplayed = this.getY();
        }
    }

    @Override
    public boolean onTouchEvent(MotionEvent event) {
        int color;
        if (event.getAction() == MotionEvent.ACTION_UP) {
            color = mColor;
        } else {
            color = darkenColor(mColor);
        }
        mButtonPaint.setColor(color);
        invalidate();
        return super.onTouchEvent(event);
    }

    public void hide(boolean hide) {
        // If the hidden state is being updated
        if (mHidden != hide) {

            // Store the new hidden state
            mHidden = hide;

            // Animate the FAB to it's new Y position
            ObjectAnimator animator = ObjectAnimator.ofFloat(this, "Y",
                    mHidden ? mYHidden : mYDisplayed);
            animator.setInterpolator(mInterpolator);
            animator.start();
        }
    }

    public void listenTo(AbsListView listView) {
        if (null != listView) {
            listView.setOnScrollListener(new DirectionScrollListener(this));
        }
    }

    public static int darkenColor(int color) {
        float[] hsv = new float[3];
        Color.colorToHSV(color, hsv);
        hsv[2] *= 0.8f;
        return Color.HSVToColor(hsv);
    }
}