Android 逐帧动画OOM的解决方法

项目中都会使用到动画，有时候会使用到逐帧动画，然后当帧数较多时，就会发生OOM的问题，网上有许多文字是提供一个工具类，解决这个方法。 关于这个工具类的使用的原文地址：http://blog.csdn.net/u014702999/article/details/50544455

效果图（图片是gif需要等待一下才可以使用）：

这篇文章主要是换一种思路，如果我们只是需要动画每隔一段时间重复一次。那么我们仅使用gif图片进行展示就可以实现效果，下面提供一个我使用的GifView类，

内存由原来的180M降到了14M

package com.alpha.alphaapp.anim; import android.annotation.SuppressLint; import android.content.Context; import android.content.res.TypedArray; import android.graphics.Canvas; import android.graphics.Movie; import android.os.Build; import android.util.AttributeSet; import android.view.View; import com.alpha.alphaapp.R; public class GifView extends View { /** * 默认为1秒 */ private static final int DEFAULT_MOVIE_DURATION = 1000; private int mMovieResourceId; private Movie mMovie; private long mMovieStart; //当前动画 private int mCurrentAnimationTime = 0; private float mLeft; private float mTop; private float mScale; private int mMeasuredMovieWidth; private int mMeasuredMovieHeight; private boolean mVisible = true; private volatile boolean mPaused = false; public GifView(Context context) { this(context, null); } public GifView(Context context, AttributeSet attrs) { this(context, attrs, R.styleable.CustomTheme_gifViewStyle); } public GifView(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); setViewAttributes(context, attrs, defStyle); } @SuppressLint("NewApi") private void setViewAttributes(Context context, AttributeSet attrs, int defStyle) { if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) { setLayerType(View.LAYER_TYPE_SOFTWARE, null); } // 从描述文件中读出gif的值，创建出Movie实例 final TypedArray array = context.obtainStyledAttributes(attrs, R.styleable.GifView, defStyle, R.style.Widget_GifView); mMovieResourceId = array.getResourceId(R.styleable.GifView_gif, -1); mPaused = array.getBoolean(R.styleable.GifView_paused, false); array.recycle(); if (mMovieResourceId != -1) { mMovie = Movie.decodeStream(getResources().openRawResource( mMovieResourceId)); } } /** * 设置gif图资源 * * @param movieResId */ public void setMovieResource(int movieResId) { this.mMovieResourceId = movieResId; mMovie = Movie.decodeStream(getResources().openRawResource( mMovieResourceId)); requestLayout(); } public void setMovie(Movie movie) { this.mMovie = movie; requestLayout(); } /** * 这里会停在最后一帧 */ public void stop() { this.mPaused = true; //获取最后一帧,主要是为了让动画在设置暂停时停在最后一帧 mCurrentAnimationTime = mMovie.duration(); invalidate(); } /** * 开始动画,重第一帧开始 */ public void start() { this.mPaused = false; //获取最后一帧,主要是为了让动画在设置暂停时停在最后一帧 mCurrentAnimationTime = 0; invalidate(); //开始动画 } public Movie getMovie() { return mMovie; } public void setMovieTime(int time) { mCurrentAnimationTime = time; invalidate(); } /** * 设置暂停 * * @param paused */ public void setPaused(boolean paused) { this.mPaused = paused; if (!paused) { mMovieStart = android.os.SystemClock.uptimeMillis() - mCurrentAnimationTime; } invalidate(); } /** * 判断gif图是否停止了 * * @return */ public boolean isPaused() { return this.mPaused; } @Override protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { if (mMovie != null) { int movieWidth = mMovie.width(); int movieHeight = mMovie.height(); int maximumWidth = MeasureSpec.getSize(widthMeasureSpec); float scaleW = (float) movieWidth / (float) maximumWidth; mScale = 1f / scaleW; mMeasuredMovieWidth = maximumWidth; mMeasuredMovieHeight = (int) (movieHeight * mScale); setMeasuredDimension(mMeasuredMovieWidth, mMeasuredMovieHeight); } else { setMeasuredDimension(getSuggestedMinimumWidth(), getSuggestedMinimumHeight()); } } @Override protected void onLayout(boolean changed, int l, int t, int r, int b) { super.onLayout(changed, l, t, r, b); mLeft = (getWidth() - mMeasuredMovieWidth) / 2f; mTop = (getHeight() - mMeasuredMovieHeight) / 2f; mVisible = getVisibility() == View.VISIBLE; } @Override protected void onDraw(Canvas canvas) { if (mMovie != null) { if (!mPaused) { updateAnimationTime(); drawMovieFrame(canvas); invalidateView(); } else { drawMovieFrame(canvas); } } } @SuppressLint("NewApi") private void invalidateView() { if (mVisible) { if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN) { postInvalidateOnAnimation(); } else { invalidate(); } } } private void updateAnimationTime() { long now = android.os.SystemClock.uptimeMillis(); // 如果第一帧，记录起始时间 if (mMovieStart == 0) { mMovieStart = now; } // 取出动画的时长 int dur = mMovie.duration(); if (dur == 0) { dur = DEFAULT_MOVIE_DURATION; } // 算出需要显示第几帧 mCurrentAnimationTime = (int) ((now - mMovieStart) % dur); } private void drawMovieFrame(Canvas canvas) { // 设置要显示的帧，绘制即可 mMovie.setTime(mCurrentAnimationTime); canvas.save(Canvas.MATRIX_SAVE_FLAG); canvas.scale(mScale, mScale); mMovie.draw(canvas, mLeft / mScale, mTop / mScale); canvas.restore(); } @SuppressLint("NewApi") @Override public void onScreenStateChanged(int screenState) { super.onScreenStateChanged(screenState); mVisible = screenState == SCREEN_STATE_ON; invalidateView(); } @SuppressLint("NewApi") @Override protected void onVisibilityChanged(View changedView, int visibility) { super.onVisibilityChanged(changedView, visibility); mVisible = visibility == View.VISIBLE; invalidateView(); } @Override protected void onWindowVisibilityChanged(int visibility) { super.onWindowVisibilityChanged(visibility); mVisible = visibility == View.VISIBLE; invalidateView(); } }

这个类是在别人的博客中找到的，自己又进行一些简单的修改，实现的效果与我用逐帧动画实现的效果一样，但内存由原来的180M降到了14M,简直瞬间感觉app都跑的快了，

在res/attrs中添加如下代码：

<!--gitView--> <declare-styleable name="GifView"> <attr name="gif" format="reference" /> <attr name="paused" format="boolean" /> </declare-styleable> <declare-styleable name="CustomTheme"> <attr name="gifViewStyle" format="reference" /> </declare-styleable>

关于这类的使用如下，也是特别简单： layout.xml

<com.alpha.alphaapp.anim.GifView android:id="@+id/login_iv_sheep" android:layout_width="147.5dp" android:enabled="false" android:layout_height="match_parent" />

MainActvity中的使用

R.raw.animation_sheep_normal与R.raw.animation_super_normal就是放置到res/raw的gif图片资源

gif_sheep = (GifView) findViewById(R.id.login_iv_sheep); gif_super = (GifView) findViewById(R.id.login_iv_super); gif_sheep.setMovieResource(R.raw.animation_sheep_normal); gif_super.setMovieResource(R.raw.animation_super_normal); isStop = false; //每隔三秒开始播放动画 runnable = new Runnable() { @Override public void run() { //动画 gif_sheep.setPaused(isStop); gif_super.setPaused(isStop); isStop=!isStop; handler.postDelayed(this, 3000); } }; handler.postDelayed(runnable, 0);

Stop动画

public void stopNormalAnim() { gif_sheep.stop(); gif_super.stop(); handler.removeCallbacks(runnable); }

onDestroy 最后在onDestroy中暂停动画

if（null!=gif_super） gif_super.setPaused(true);

这篇文章的题目有点与内容不符，但是我们在开发中，不就是实现了效果为主么，实现方式尽可能的简化。希望对大家有帮助。