Multi-color water ripple diffusion effect

Layout

<relativelayout xmlns:android= "http://schemas.android.com/apk/res/android"    xmlns:tools= "http// Schemas.android.com/tools "    android:layout_width=" Match_parent "    android:layout_height = "Match_parent"    tools:context= ". Mainactivity ">    <com.ee.MyWave        android:layout_width=" Match_parent "        android: Layout_height= "Match_parent" >    </com.ee.MyWave></RelativeLayout>

Class

 Packagecom.ee;Importjava.util.ArrayList;ImportAndroid.content.Context;ImportAndroid.graphics.Canvas;ImportAndroid.graphics.Color;ImportAndroid.graphics.Paint;ImportAndroid.graphics.Paint.Style;ImportAndroid.os.Handler;ImportAndroid.util.AttributeSet;Importandroid.view.MotionEvent;ImportAndroid.view.View;/*** Water Ripple effect*/ Public classMywaveextendsView {/*** Define a water wave class (a circle includes the center, RADIUS, brush (required to draw))*/    Private classWave {//Center        intPointx; intPointy; //radius        intradius; //BrushesPaint paint; }    //the minimum distance between the two and the center point of a wave    Private Static Final intDIS_SOLP = 13; //whether there is water wave    protected BooleanIsRunning =false; /*** First Step builder*/    //define the set of water ripples    PrivateArraylist<wave>wlist;  PublicMywave (Context context, AttributeSet attrs) {Super(context, attrs); //Initialize Create water ripple setWlist =NewArraylist<mywave.wave>(); }    /*** Touch Event*/@Override Public Booleanontouchevent (Motionevent event) {Super. Ontouchevent (event); Switch(Event.getaction ()) {//Press the screen, swipe to create water waves         CaseMotionevent.action_down: CaseMotionevent.action_move://get the center of the down and move            intx = (int) Event.getx (); inty = (int) event.gety (); //If the water ripple set is empty, draw a water ripple            if(wlist.size () = = 0) {                //Draw Water Rippleaddpoint2list (x, y); //modify the state to indicate the formation of water wavesIsRunning =true; //now send a message stating that a water wave was drawnHandler.sendemptymessage (0); } Else {                //If the wave set is not empty, go to the last drawn circular water waveWave w = wlist.get (Wlist.size ()-1); if(Math.Abs (W.pointx-x) >Dis_solp|| Math.Abs (w.pointy-y) >Dis_solp)                {addpoint2list (x, y);            }            }            ;  Break; default:             Break; }        return true; }    /** Define 4 colors of water waves*/    Private int[] Colors =New int[] {color.blue, color.red, Color.yellow, color.green}; /*** Add Waves*/    Private voidAddpoint2list (intXinty) {//Create a water wave classWave W =NewWave (); //Assign values to the water wave class by sliding or pressing the coordinatesW.pointx =x; W.pointy=y; //Create a brushPaint PA =NewPaint (); //Draw a water wave (ring) set color, antialiasing, ShapePa.setcolor (colors[(int) (Math.random () * 4)]); Pa.setantialias (true);        Pa.setstyle (Style.stroke); //Assign ValueW.paint =PA; //add a circular wave to the collectionWlist.add (W); }    /*** Draw Water Ripple*/@Overrideprotected voidOnDraw (canvas canvas) { for(inti = 0; I < wlist.size (); i++) {Wave wave=Wlist.get (i);        Canvas.drawcircle (Wave.pointx, Wave.pointy, Wave.radius, Wave.paint); }    }    /** Using message mechanism*/    PrivateHandler Handler =NewHandler () { Public voidhandlemessage (android.os.Message msg) {//accept the message sent to the appropriate action//Refresh DataFlushData (); //Refresh Pageinvalidate (); //Looping animations            if(isrunning) {handler.sendemptymessagedelayed (0, 50);    }        };    }; /*** Refresh the data (the transparency of the operation ring water and the change in radius)*/    Private voidFlushData () { for(inti = 0; I < wlist.size (); i++) {Wave W=Wlist.get (i); //If the transparency is 0 removed from the collection            intAlpha =W.paint.getalpha (); if(Alpha = = 0) {wlist.remove (i); Continue; }            //minus 5 per transparency valueAlpha-= 5; if(Alpha < 5) {Alpha= 0; }            //Reduce TransparencyW.paint.setalpha (Alpha); //Enlarge radiusW.radius = W.radius + 3; //Set radius thicknessW.paint.setstrokewidth (W.RADIUS/3); }        /** Stop refreshing animations If the collection is emptied*/        if(wlist.size () = = 0) {isrunning=false; }    }}

Multi-color water ripple diffusion effect