我的画面动画滞后。为什么会滞后？
代码：
public class LiveWallpaperService extends WallpaperService {
Bitmap mPic;
private final Handler mHandler = new Handler();
@Override
public void onCreate() {
super.onCreate();
}
@Override
public void onDestroy() {
super.onDestroy();
}
@Override
public Engine onCreateEngine() {
return new CubeEngine();
}
class CubeEngine extends Engine {
private float mPosY, mPosX;
private Matrix mMatrix = new Matrix();
private int k = 1;
private boolean mAnime = true;
private boolean test;
private static final int NUM_RES = 30;
private final Runnable mDrawAnim = new Runnable() {
public void run() {
for (int i = 0; i < 31; i++) {
k++;
drawFrame();
if (i == 30) {
k = 1;
}
}
}
};
private boolean mVisible;
CubeEngine() {
Resources res = getResources();
for (int i = 0; i < NUM_RES; i++) {
int id = res.getIdentifier("boot_00" + (100 + (i + 1)),
"drawable", "com.example.dxd1");
mPic = BitmapFactory.decodeResource(res, id);
}
}
@Override
public void onCreate(SurfaceHolder surfaceHolder) {
super.onCreate(surfaceHolder);
setTouchEventsEnabled(false);
}
@Override
public void onDestroy() {
super.onDestroy();
mHandler.removeCallbacks(mDrawAnim);
}
@Override
public void onVisibilityChanged(boolean visible) {
mVisible = visible;
if (visible) {
drawFrame();
}else {
mHandler.removeCallbacks(mDrawAnim);
}
}
@Override
public void onSurfaceChanged(SurfaceHolder holder, int format,
int width, int height) {
super.onSurfaceChanged(holder, format, width, height);
float w = mPic.getWidth();
float h = mPic.getHeight();
float s = width / (float) w;
float s2 = height / (float) h;
mMatrix.reset();
mMatrix.setScale(s, s2);
}
@Override
public void onSurfaceCreated(SurfaceHolder holder) {
super.onSurfaceCreated(holder);
}
@Override
public void onSurfaceDestroyed(SurfaceHolder holder) {
super.onSurfaceDestroyed(holder);
mVisible = false;
mHandler.removeCallbacks(mDrawAnim);
}
public void updateBG() {
if (k == 1) {
mPic = BitmapFactory.decodeResource(getResources(),
R.drawable.boot_00101);
}
if (k == 2) {
mPic = BitmapFactory.decodeResource(getResources(),
R.drawable.boot_00102);
}
if (k == 3) {
mPic = BitmapFactory.decodeResource(getResources(),
R.drawable.boot_00103);
}
if (k == 4) {
mPic = BitmapFactory.decodeResource(getResources(),
R.drawable.boot_00104);
}
if (k == 5) {
mPic = BitmapFactory.decodeResource(getResources(),
R.drawable.boot_00105);
}
if (k == 6) {
mPic = BitmapFactory.decodeResource(getResources(),
R.drawable.boot_00106);
}
if (k == 7) {
mPic = BitmapFactory.decodeResource(getResources(),
R.drawable.boot_00107);
}
if (k == 8) {
mPic = BitmapFactory.decodeResource(getResources(),
R.drawable.boot_00108);
}
if (k == 9) {
mPic = BitmapFactory.decodeResource(getResources(),
R.drawable.boot_00109);
}
if (k == 10) {
mPic = BitmapFactory.decodeResource(getResources(),
R.drawable.boot_00110);
}
if (k == 11) {
mPic = BitmapFactory.decodeResource(getResources(),
R.drawable.boot_00111);
}
if (k == 12) {
mPic = BitmapFactory.decodeResource(getResources(),
R.drawable.boot_00112);
}
if (k == 13) {
mPic = BitmapFactory.decodeResource(getResources(),
R.drawable.boot_00113);
}
if (k == 14) {
mPic = BitmapFactory.decodeResource(getResources(),
R.drawable.boot_00114);
}
if (k == 15) {
mPic = BitmapFactory.decodeResource(getResources(),
R.drawable.boot_00115);
}
if (k == 16) {
mPic = BitmapFactory.decodeResource(getResources(),
R.drawable.boot_00116);
}
if (k == 17) {
mPic = BitmapFactory.decodeResource(getResources(),
R.drawable.boot_00117);
}
if (k == 18) {
mPic = BitmapFactory.decodeResource(getResources(),
R.drawable.boot_00118);
}
if (k == 19) {
mPic = BitmapFactory.decodeResource(getResources(),
R.drawable.boot_00119);
}
if (k == 20) {
mPic = BitmapFactory.decodeResource(getResources(),
R.drawable.boot_00120);
}
if (k == 21) {
mPic = BitmapFactory.decodeResource(getResources(),
R.drawable.boot_00121);
}
if (k == 22) {
mPic = BitmapFactory.decodeResource(getResources(),
R.drawable.boot_00122);
}
if (k == 23) {
mPic = BitmapFactory.decodeResource(getResources(),
R.drawable.boot_00123);
}
if (k == 24) {
mPic = BitmapFactory.decodeResource(getResources(),
R.drawable.boot_00124);
}
if (k == 25) {
mPic = BitmapFactory.decodeResource(getResources(),
R.drawable.boot_00125);
}
if (k == 26) {
mPic = BitmapFactory.decodeResource(getResources(),
R.drawable.boot_00126);
}
if (k == 27) {
mPic = BitmapFactory.decodeResource(getResources(),
R.drawable.boot_00127);
}
if (k == 28) {
mPic = BitmapFactory.decodeResource(getResources(),
R.drawable.boot_00128);
}
if (k == 29) {
mPic = BitmapFactory.decodeResource(getResources(),
R.drawable.boot_00129);
}
if (k == 30) {
mPic = BitmapFactory.decodeResource(getResources(),
R.drawable.boot_00130);
}
}
void drawFrame() {
final SurfaceHolder holder = getSurfaceHolder();
Canvas c = null;
c = holder.lockCanvas();
if (c != null) {
drawAnim(c);
}
if (c != null) {
holder.unlockCanvasAndPost(c);
}
// Reschedule the next redraw
mHandler.removeCallbacks(mDrawAnim);
if (mVisible && mAnime) {
mHandler.postDelayed(mDrawAnim, 50);
}
}
void drawAnim(Canvas c) {
updateBG();
c.drawBitmap(mPic, mMatrix, null);
}
}
答案 0 :(得分：1)
在绘制线程上解码位图非常重，肯定会导致延迟。您不能只为每个帧绘制带有全屏位图的动画。您将不得不缓存它们（不太可能，因为您将用完全屏幕位图的RAM），或者您必须以编程方式绘制内容（所以动态生成的图像）或仅使用部分位图/图层（不是他们叫精灵？）并移动这些部分。
我为客户开发了一个带有位图的全屏动画介绍的应用程序，在大多数设备上它不会达到5fps，而（原始）iphone版本达到了更多。我只使用了h264编码的电影（其他兼容性问题）。所以，这种方式不起作用。
所以，主要的问题是，为什么你使用30位图来绘制东西？你不能使用图层，所以你使用较小的位图？也许你自己动画一下？为什么不使用电影而不是手动动画？你在使用全屏图像吗？
如果您不使用全屏图像，可能会实现某种预缓存，因此您在渲染之前已经将2个图像解码为位图，同时保持缓存更新。