Switch.java

package com.gc.materialdesign.views;

import com.gc.materialdesign.R;
import com.gc.materialdesign.utils.Utils;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.PorterDuff;
import android.graphics.PorterDuffXfermode;
import android.graphics.drawable.GradientDrawable;
import android.graphics.drawable.LayerDrawable;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;
import android.widget.RelativeLayout;

public class Switch extends CustomView {
	
	final static String ANDROIDXML = "http://schemas.android.com/apk/res/android";
	
	int backgroundColor = Color.parseColor("#4CAF50");
	
	Ball ball;
	
	boolean check = false;
	boolean press = false;

	public Switch(Context context, AttributeSet attrs) {
		super(context, attrs);
		setAttributes(attrs);
		setOnClickListener(new OnClickListener() {
			
			@Override
			public void onClick(View arg0) {
				if(check)
					setChecked(false);
				else
					setChecked(true);
			}
		});
	}
	
	// Set atributtes of XML to View
	protected void setAttributes(AttributeSet attrs){
		
		setBackgroundResource(R.drawable.background_transparent);
		
		// Set size of view
		setMinimumHeight(Utils.dpToPx(48, getResources()));
		setMinimumWidth(Utils.dpToPx(80, getResources()));
		
		//Set background Color
		// Color by resource
		int bacgroundColor = attrs.getAttributeResourceValue(ANDROIDXML,"background",-1);
		if(bacgroundColor != -1){
			setBackgroundColor(getResources().getColor(bacgroundColor));
		}else{
			// Color by hexadecimal
			String background = attrs.getAttributeValue(ANDROIDXML,"background");
			if(background != null)
				setBackgroundColor(Color.parseColor(background));
		}
		
		check = attrs.getAttributeBooleanValue(MATERIALDESIGNXML,"check", false);
		
		ball = new Ball(getContext());
		RelativeLayout.LayoutParams params = new LayoutParams(Utils.dpToPx(20, getResources()),Utils.dpToPx(20, getResources()));
		params.addRule(RelativeLayout.CENTER_VERTICAL, RelativeLayout.TRUE);
		ball.setLayoutParams(params);
		addView(ball);
					
	}
	
	@Override
	public boolean onTouchEvent(MotionEvent event) {
		isLastTouch = true;
		if (event.getAction() == MotionEvent.ACTION_DOWN) {
			press = true;
		}else if(event.getAction() == MotionEvent.ACTION_MOVE) {
			float x = event.getX();
			x = (x < ball.xIni)? ball.xIni : x;
			x = (x > ball.xFin)? ball.xFin : x;
			if(x > ball.xCen){
				check = true;
				
			}else{
				check = false;
			}
				ball.setX(x);
			ball.changeBackground();
			if((event.getX()<= getWidth() && event.getX() >= 0) && 
					(event.getY()<= getHeight() && event.getY() >= 0)){
				isLastTouch = false;
				press = false;
			}
		}
		else if (event.getAction() == MotionEvent.ACTION_UP) {
			press = false;
			isLastTouch = false;
			if((event.getX()<= getWidth() && event.getX() >= 0) && 
					(event.getY()<= getHeight() && event.getY() >= 0)){
//				check = !check;
//				ball.changeBackground();
				ball.animateCheck();
			}
		}
		return true;
	}
	
	@Override
	protected void onDraw(Canvas canvas) {
		super.onDraw(canvas);
		if(!placedBall)
			placeBall();
		
		// Crop line to transparent effect
		Bitmap bitmap = Bitmap.createBitmap(canvas.getWidth(), canvas.getHeight(), Bitmap.Config.ARGB_8888);
	    Canvas temp = new Canvas(bitmap);
	    Paint paint = new Paint();
	    paint.setAntiAlias(true);
		paint.setColor((check)?backgroundColor:Color.parseColor("#B0B0B0"));
		paint.setStrokeWidth(Utils.dpToPx(2, getResources()));
		temp.drawLine(getHeight()/2, getHeight()/2, getWidth()-getHeight()/2, getHeight()/2, paint);
	    Paint transparentPaint = new Paint();
	    transparentPaint.setAntiAlias(true);
	    transparentPaint.setColor(getResources().getColor(android.R.color.transparent));
	    transparentPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.CLEAR));
	    temp.drawCircle(ball.getX()+ball.getWidth()/2, ball.getY()+ball.getHeight()/2, ball.getWidth()/2, transparentPaint);

	    canvas.drawBitmap(bitmap, 0, 0, new Paint());
	    
	    if(press){
			paint.setColor((check)?makePressColor():Color.parseColor("#446D6D6D"));
			canvas.drawCircle(ball.getX()+ball.getWidth()/2, getHeight()/2, getHeight()/2, paint);
		}
		invalidate();
		
	}
	
	
	
	/**
	 * Make a dark color to press effect
	 * @return
	 */
	protected int makePressColor(){
		int r = (this.backgroundColor >> 16) & 0xFF;
		int g = (this.backgroundColor >> 8) & 0xFF;
		int b = (this.backgroundColor >> 0) & 0xFF;
		r = (r-30 < 0) ? 0 : r-30;
		g = (g-30 < 0) ? 0 : g-30;
		b = (b-30 < 0) ? 0 : b-30;
		return Color.argb(70,r, g, b);		
	}
	
	// Move ball to first position in view
	boolean placedBall = false;
	private void placeBall(){
		ball.setX(getHeight()/2 - ball.getWidth()/2);
		ball.xIni = ball.getX();
		ball.xFin = getWidth()-getHeight()/2-ball.getWidth()/2;
		ball.xCen = getWidth() / 2-ball.getWidth()/2;
		placedBall = true;
		ball.animateCheck();
	}
	
	//	SETTERS
	
	@Override
	public void setBackgroundColor(int color) {
		backgroundColor = color;
	}
	
	public void setChecked(boolean check){
		this.check = check;
		ball.animateCheck();
	}
	
	class Ball extends View{
		
		float xIni, xFin, xCen;

		public Ball(Context context) {
			super(context);
			setBackgroundResource(R.drawable.background_switch_ball_uncheck);
		}
	
	
		public void changeBackground(){
			if(check){
				setBackgroundResource(R.drawable.background_checkbox);
				LayerDrawable layer = (LayerDrawable) getBackground();
				GradientDrawable shape =  (GradientDrawable) layer.findDrawableByLayerId(R.id.shape_bacground);
				shape.setColor(backgroundColor);
			}else{
				setBackgroundResource(R.drawable.background_switch_ball_uncheck);
			}
		}
		
		public void animateCheck(){
			changeBackground();
			if(check){
				animate().x(ball.xFin).setDuration(300).start();
			}else{
				animate().x(ball.xIni).setDuration(300).start();
			}
		}
		
		
	
	}

}