AnimatedHoldButton.java

package com.llamacorp.equate.view;

import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Color;
import android.graphics.drawable.Drawable;
import android.os.Build;
import android.os.Handler;
import android.support.v4.content.ContextCompat;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;

import com.llamacorp.equate.R;

public class AnimatedHoldButton extends SecondaryTextButton {
	private final int CLICK_HOLD_TIME;

	protected float mSecAdditionalXOffset = getContext().getResources().
			  getDimensionPixelSize(R.dimen.button_secondary_text_additional_offset_x);
	protected float mSecAdditionalYOffset = getContext().getResources().
			  getDimensionPixelSize(R.dimen.button_secondary_text_additional_offset_y);


	private OnClickListener mClickListen = null;
	private OnLongClickListener mLongClickListen = null;
	private OnExtraLongClickListener mExtraLongClickListener = null;
	private Handler mColorHoldHandler;
	private boolean mLongClickPerformed = false;
	private boolean mWaitingForExtraLongClick = false;
	private Drawable mNormalDrawable;
	private int mPressedColor;

	//used to count up holding time
	private int mHoldInc;

	private String mPrimaryText;


	public AnimatedHoldButton(Context context, AttributeSet attrs) {
		super(context, attrs);

		CLICK_HOLD_TIME = ViewUtils.getLongClickTimeout(context);

		mPrimaryText = "";

		mNormalDrawable = getBackground();

		TypedArray ta = context.obtainStyledAttributes(attrs, R.styleable.AnimatedHoldButton, 0, 0);
		try {
			mPrimaryText = ta.getString(R.styleable.AnimatedHoldButton_primary_text);
			mPressedColor = ta.getColor(R.styleable.AnimatedHoldButton_pressed_color,
					  ContextCompat.getColor(context, R.color.op_button_pressed));
		} finally {
			ta.recycle();
		}

		//this is needed for so paint knows what to measure in layoutText
		setText(mPrimaryText);
	}

	@Override
	protected void findSecondaryTextCoordinates() {
		mSecXCord = mButtonWidth - mSecTextWidth - mSecAdditionalXOffset;
		mSecYCord = 0 + mSecTextHeight + mSecAdditionalYOffset;
	}

	/**
	 * Setup custom clicking and long clicking handlers
	 * Click will be performed if button is pressed down and released
	 * before the long click timeout.  As the long click timeout is
	 * expiring, button's color will change and finally flash at the timeout
	 * event, at which point the long click function will be called.
	 */
	@SuppressWarnings("deprecation") //for setBackgroundDrawable
	public boolean onTouchEvent(MotionEvent event) {
		switch (event.getAction()) {
			case MotionEvent.ACTION_DOWN:
				mHoldInc = 0;

				if (mColorHoldHandler != null) return true;
				mColorHoldHandler = new Handler();
				mColorHoldHandler.postDelayed(mColorRunnable, 10);
				break;
			case MotionEvent.ACTION_UP:
				if (mColorHoldHandler == null) return true;
				if (!mLongClickPerformed)
					clickButton();

				mLongClickPerformed = false;
				mWaitingForExtraLongClick = false;

				if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN)
					setBackground(mNormalDrawable);
				else setBackgroundDrawable(mNormalDrawable);

				mColorHoldHandler.removeCallbacks(mColorRunnable);
				mColorHoldHandler = null;

				postInvalidate();
				break;
		}
		return true;
	}


	//set up the runnable for when button is held down
	Runnable mColorRunnable = new Runnable() {
		private static final int NUM_COLOR_CHANGES = 10;
		private Integer mGradStartCol, mGradEndCol, mAccentColor, mFinalColor;

		@Override
		public void run() {
			initializeColors();

			if (mWaitingForExtraLongClick){
				extraLongClickButton();
				return;
			}

			//after hold operation is performed and 100ms is up, set final color
			if (mLongClickPerformed){
				setBackgroundColor(mFinalColor);

				//set up another delay to wait for a very long click
				mColorHoldHandler.postDelayed(this, 2000);
				mWaitingForExtraLongClick = true;
				return;
			}

			//color the button black for a second and perform long click operation
			if (mHoldInc == NUM_COLOR_CHANGES){
				longClickButton();
				mLongClickPerformed = true;
				setBackgroundColor(mAccentColor);
				//only post again so it runs to catch the final bit of code
				mColorHoldHandler.postDelayed(this, 100);
				return;
			}

			mColorHoldHandler.postDelayed(this, CLICK_HOLD_TIME / NUM_COLOR_CHANGES);

			float deltaRed = (float) Color.red(mGradStartCol) + ((float) Color.red(mGradEndCol) - (float) Color.red(mGradStartCol)) * ((float) mHoldInc) / ((float) NUM_COLOR_CHANGES);
			float deltaGreen = (float) Color.green(mGradStartCol) + ((float) Color.green(mGradEndCol) - (float) Color.green(mGradStartCol)) * ((float) mHoldInc) / ((float) NUM_COLOR_CHANGES);
			float deltaBlue = (float) Color.blue(mGradStartCol) + ((float) Color.blue(mGradEndCol) - (float) Color.blue(mGradStartCol)) * ((float) mHoldInc) / ((float) NUM_COLOR_CHANGES);

			setBackgroundColor(Color.argb(255, (int) deltaRed, (int) deltaGreen, (int) deltaBlue));
			mHoldInc++;
		}

		/**
		 * Helper method so colors only get initialed once
		 */
		private void initializeColors() {
			if (mGradStartCol == null){
				mGradStartCol = mPressedColor;
				mGradEndCol = ContextCompat.getColor(getContext(),
						  R.color.op_button_long_press_accent);
				mAccentColor = mPressedColor;
				mFinalColor = mPressedColor;
			}
		}
	};

	/**
	 * Calls listener's onClick, which gets setup by code controlling button
	 */
	private void clickButton() {
		if (mClickListen != null)
			mClickListen.onClick(this);
	}

	/**
	 * Calls listener's onLongClick, which gets setup by code controlling button
	 */
	private void longClickButton() {
		if (mLongClickListen != null)
			mLongClickListen.onLongClick(this);
	}

	private void extraLongClickButton() {
		if (mExtraLongClickListener != null)
			mExtraLongClickListener.onExtraLongClick(this);
	}

	public void setPrimaryText(CharSequence text) {
		super.setText(text);
		mPrimaryText = text.toString();
	}

	@Override
	protected String getPrimaryText() {
		if (mPrimaryText == null)
			return "";
		return mPrimaryText;
	}

	@Override
	public void setOnClickListener(OnClickListener l) {
		mClickListen = l;
	}

	@Override
	public void setOnLongClickListener(OnLongClickListener l) {
		mLongClickListen = l;
	}

	public void setOnExtraLongClickListener(OnExtraLongClickListener l) {
		mExtraLongClickListener = l;
	}

	public interface OnExtraLongClickListener {
		void onExtraLongClick(View var1);
	}
}