Android動(dòng)態(tài)壁紙的制作教程.docx

動(dòng)態(tài)壁紙是在Android 2.1新增的一個(gè)功能。動(dòng)態(tài)壁紙可以添加到Android的桌面，具有交互式的動(dòng)畫背景效果。在本教程中，我們將教會(huì)你如何去制作一個(gè)交互式的動(dòng)態(tài)壁紙。動(dòng)態(tài)壁紙是一個(gè)Android應(yīng)用程序，包括一個(gè)服務(wù)(WallpaperService)。該服務(wù)必須包括一個(gè)引擎(WallpaperService.Engine)。該引擎是連接用戶、桌面、系統(tǒng)之間的橋梁。它也可以繪制桌面壁紙。首先，必須由內(nèi)在的Engine類創(chuàng)建一個(gè)WallpaperService類。該服務(wù)必須在AndroidManifest.xml中聲明為android.service.wallpaper.WallpaperService，這樣它才會(huì)作為動(dòng)態(tài)壁紙被手機(jī)識(shí)別。而且還要在服務(wù)配置中附加android.permission.BIND_WALLPAPER的權(quán)限許可：?12345678910111213創(chuàng)建一個(gè)XML文件，放置在應(yīng)用程序目錄下的/res/xml/中。它用來描述你的動(dòng)態(tài)壁紙。?123456再創(chuàng)建一個(gè)xml的屬性文件attrs.xml，代碼如下：?1234567891011121314動(dòng)態(tài)壁紙的服務(wù)代碼如下：?123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105package net.androgames.blog.sample.livewallpaper;import android.content.SharedPreferences;import android.service.wallpaper.WallpaperService;import android.view.MotionEvent;import android.view.SurfaceHolder;/* Android Live Wallpaper Archetype* author antoine vianey* under GPL v3 : /licenses/gpl-3.0.html*/public class LiveWallpaperService extends WallpaperService Overridepublic Engine onCreateEngine() return new SampleEngine();Overridepublic void onCreate() super.onCreate();Overridepublic void onDestroy() super.onDestroy();public class SampleEngine extends Engine private LiveWallpaperPainting painting;SampleEngine() SurfaceHolder holder = getSurfaceHolder();painting = new LiveWallpaperPainting(holder, getApplicationContext();Overridepublic void onCreate(SurfaceHolder surfaceHolder) super.onCreate(surfaceHolder);/ register listeners and callbacks heresetTouchEventsEnabled(true);Overridepublic void onDestroy() super.onDestroy();/ remove listeners and callbacks herepainting.stopPainting();Overridepublic void onVisibilityChanged(boolean visible) if (visible) / register listeners and callbacks herepainting.resumePainting(); else / remove listeners and callbacks herepainting.pausePainting();Overridepublic void onSurfaceChanged(SurfaceHolder holder, int format, int width, int height) super.onSurfaceChanged(holder, format, width, height);painting.setSurfaceSize(width, height);Overridepublic void onSurfaceCreated(SurfaceHolder holder) super.onSurfaceCreated(holder);/ start paintingpainting.start();Overridepublic void onSurfaceDestroyed(SurfaceHolder holder) super.onSurfaceDestroyed(holder);boolean retry = true;painting.stopPainting();while (retry) try painting.join();retry = false; catch (InterruptedException e) Overridepublic void onOffsetsChanged(float xOffset, float yOffset, float xStep, float yStep, int xPixels, int yPixels) Overridepublic void onTouchEvent(MotionEvent event) super.onTouchEvent(event);painting.doTouchEvent(event);當(dāng)壁紙的顯示、狀態(tài)或大小變化是，會(huì)調(diào)用Engine的onCreate,onDestroy,onVisibilityChanged,onSurfaceChanged,onSurfaceCreated和onSurfaceDestroyed方法。有了這些方法，動(dòng)態(tài)壁紙才能展現(xiàn)出動(dòng)畫效果。而通過設(shè)置setTouchEventsEnabled（true），并且調(diào)用onTouchEvent（MotionEvent event）方法，來激活觸摸事件。我們?cè)诶L畫墻紙的時(shí)候，也會(huì)使用一個(gè)單獨(dú)的繪畫線程：?123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140package net.androgames.blog.sample.livewallpaper;import android.content.Context;import android.graphics.Canvas;import android.view.MotionEvent;import android.view.SurfaceHolder;/* Android Live Wallpaper painting thread Archetype* author antoine vianey* GPL v3 : /licenses/gpl-3.0.html*/public class LiveWallpaperPainting extends Thread /* Reference to the View and the context */private SurfaceHolder surfaceHolder;private Context context;/* State */private boolean wait;private boolean run;/* Dimensions */private int width;private int height;/* Time tracking */private long previousTime;private long currentTime;public LiveWallpaperPainting(SurfaceHolder surfaceHolder, Context context) / keep a reference of the context and the surface/ the context is needed if you want to inflate/ some resources from your livewallpaper .apkthis.surfaceHolder = surfaceHolder;this.context = context;/ dont animate until surface is created and displayedthis.wait = true;/* Pauses the live wallpaper animation*/public void pausePainting() this.wait = true;synchronized(this) this.notify();/* Resume the live wallpaper animation*/public void resumePainting() this.wait = false;synchronized(this) this.notify();/* Stop the live wallpaper animation*/public void stopPainting() this.run = false;synchronized(this) this.notify();Overridepublic void run() this.run = true;Canvas c = null;while (run) try c = this.surfaceHolder.lockCanvas(null);synchronized (this.surfaceHolder) currentTime = System.currentTimeMillis();updatePhysics();doDraw(c);previousTime = currentTime; finally if (c != null) this.surfaceHolder.unlockCanvasAndPost(c);/ pause if no need to animatesynchronized (this) if (wait) try wait(); catch (Exception e) /* Invoke when the surface dimension change*/public void setSurfaceSize(int width, int height) this.width = width;this.height = height;synchronized(this) this.notify();/* Invoke while the screen is touched*/public void doTouchEvent(MotionEvent event) / handle the event here/ if there is something to animate/ then wake upthis.wait = false;synchronized(this) notify();/* Do the actual drawing stuff*/private void doDraw(Canvas canvas) /* Update the animatio