54. The effect of rain on Android particles (rain effect)

ImportAndroid.content.Context;ImportAndroid.graphics.Canvas;ImportAndroid.util.AttributeSet;ImportAndroid.view.View;/*** Base class*/ Public Abstract classBaseviewextendsView {PrivateMyThread thread; Private Booleanrunning =true;  PublicBaseview (Context context, AttributeSet attrs) {Super(context, attrs); }     PublicBaseview (Context context) {Super(context); }    protected Abstract voiddrawsub (canvas canvas); protected Abstract voidlogic (); protected Abstract voidinit (); classMyThreadextendsThread {@Override Public voidrun () {init ();  while(running) {logic ();                Postinvalidate (); Try{Thread.Sleep (30); } Catch(interruptedexception e) {e.printstacktrace (); } }} @Overrideprotected Final voidOnDraw (canvas canvas) {if(Thread = =NULL) {Thread=NewMyThread ();        Thread.Start (); } Else{drawsub (canvas); }} @Overrideprotected voidOndetachedfromwindow () {Running=false; Super. Ondetachedfromwindow (); }}

1) Simply describe the behavior of individual raindrops.

The individual that draws the rain scene, raindrops (straight lines);

Let the line move up;

Dealing with boundary problems;

1   ImportAndroid.content.Context;2 ImportAndroid.graphics.Canvas;3 ImportAndroid.graphics.Paint;4 ImportAndroid.util.AttributeSet;5 6  Public classRainviewextendsBaseview {8     Private floatStartX;9     Private floatStarty;Ten     Private floatstopx; One     Private floatstopy; A     Private floatSizex; -     Private floatSizey; -     Privatepaint paint; the  -      PublicRainview (Context context, AttributeSet attrs) { -         Super(context, attrs); +         //angle.  -Sizex = 10; +Sizey = 30; A         //The following is the coordinates of the initialized line.  atStartX = 100; -Starty = 0; -         //change the angle of the line.  -STOPX = StartX +Sizex; -Stopy = Starty +Sizey; -  inPaint =NewPaint (); -         //set the line to white.  toPaint.setcolor (0xFFFFFFFF); +     } -  the      PublicRainview (Context context) { *         Super(context); $     }Panax Notoginseng  - @Override the     protected voiddrawsub (canvas canvas) { +         //Draw a line A canvas.drawline (StartX, Starty, stopx, stopy, paint); the     } +  -@Override/*let the line move.*/  $     protected voidlogic () { $  -         //magnification to change the speed by magnification.  -         floatopt = 0.5f; the  -StartX + = Sizex *opt;WuyiSTOPX + = Sizex *opt; the  -Starty + = Sizey *opt; WuStopy + = Sizey *opt; -  About         //when the line goes out of the screen, it becomes the initial position.  $         if(Starty >getheight ()) { -StartX = 100; -Starty = 0; -STOPX = StartX + 10; AStopy = Starty + 30; +         } the     } -  $}

2) Perfect raindrop behavior and tectonic rain scene.

Constructing Raindrop objects;

Raindrop size setting;

Speed setting;

The angle setting and so on add multiple raindrops;

3) Define the properties in the XML that can control the rain.

Extracting attributes that can be affected in XML;

Parsing style attributes in code and using them to control rain changes;

54. The effect of rain on Android particles (rain effect)