編輯：關於Android編程
Android 使用幀動畫內存溢出解決方案
最近在項目遇到的動畫效果不好實現，就讓UI切成圖，采用幀動畫實現效果，但是在使用animation-list時，圖片也就11張，每張圖片大概560k左右，結果內存溢出，崩潰 了，自己用了三張都崩潰；拿代碼說；
1.anin_searh.xml
<?xml version="1.0" encoding="utf-8"?> <animation-list xmlns:android="http://schemas.android.com/apk/res/android" android:oneshot="true"> <item android:drawable="@drawable/a1" android:duration="100"></item> <item android:drawable="@drawable/a2" android:duration="100"></item> <item android:drawable="@drawable/a4" android:duration="100"></item> <item android:drawable="@drawable/a5" android:duration="100"></item> <item android:drawable="@drawable/a6" android:duration="100"></item> <item android:drawable="@drawable/a7" android:duration="100"></item> <item android:drawable="@drawable/a8" android:duration="100"></item> <item android:drawable="@drawable/a9" android:duration="100"></item> <item android:drawable="@drawable/a10" android:duration="100"></item> <item android:drawable="@drawable/a11" android:duration="100"></item> </animation-list>
2.使用幀動畫
search_scale_iv.setBackgroundResource(R.drawable.anim_search);
AnimationDrawable drawable = (AnimationDrawable) search_scale_iv.getBackground();
drawable.start();
結果setBackgroundResource出現內存溢出，這個方法其實獲取drawable時候,會消耗很多內存，很容易內存溢出，崩潰。
3.解決方法：在網上找了個類，處理，結果我使用11張560k大小圖片，沒有內存溢出；
import android.content.Context;
import android.content.res.XmlResourceParser;
import android.graphics.BitmapFactory;
import android.graphics.drawable.AnimationDrawable;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;
import android.os.Handler;
import android.widget.ImageView;
import org.apache.commons.io.IOUtils;
import org.xmlpull.v1.XmlPullParser;
import org.xmlpull.v1.XmlPullParserException;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
/****
* 此工具類源於stack over flow
* 原文鏈接:http://stackoverflow.com/questions/8692328/causing-outofmemoryerror-in-frame-by-frame-animation-in-android
* 主要使用了BitmapFactory.decodeByteArray方法通過底層C來繪制圖片,有效防止OOM
* 使用了第三方類庫:org.apache.commons.io.IOUtils,將Inputstream轉為byte字節數組
* *******/
public class MyAnimationDrawable {
public static class MyFrame {
byte[] bytes;
int duration;
Drawable drawable;
boolean isReady = false;
}
public interface OnDrawableLoadedListener {
public void onDrawableLoaded(List<MyFrame> myFrames);
}
// 1
/***
* 性能更優
* 在animation-list中設置時間
* **/
public static void animateRawManuallyFromXML(int resourceId,
final ImageView imageView, final Runnable onStart,
final Runnable onComplete) {
loadRaw(resourceId, imageView.getContext(),
new OnDrawableLoadedListener() {
@Override
public void onDrawableLoaded(List<MyFrame> myFrames) {
if (onStart != null) {
onStart.run();
}
animateRawManually(myFrames, imageView, onComplete);
}
});
}
// 2
private static void loadRaw(final int resourceId, final Context context,
final OnDrawableLoadedListener onDrawableLoadedListener) {
loadFromXml(resourceId, context, onDrawableLoadedListener);
}
// 3
private static void loadFromXml(final int resourceId,
final Context context,
final OnDrawableLoadedListener onDrawableLoadedListener) {
new Thread(new Runnable() {
@Override
public void run() {
final ArrayList<MyFrame> myFrames = new ArrayList<MyFrame>();
XmlResourceParser parser = context.getResources().getXml(
resourceId);
try {
int eventType = parser.getEventType();
while (eventType != XmlPullParser.END_DOCUMENT) {
if (eventType == XmlPullParser.START_DOCUMENT) {
} else if (eventType == XmlPullParser.START_TAG) {
if (parser.getName().equals("item")) {
byte[] bytes = null;
int duration = 1000;
for (int i = 0; i < parser.getAttributeCount(); i++) {
if (parser.getAttributeName(i).equals(
"drawable")) {
int resId = Integer.parseInt(parser
.getAttributeValue(i)
.substring(1));
bytes = IOUtils.toByteArray(context
.getResources()
.openRawResource(resId));
} else if (parser.getAttributeName(i)
.equals("duration")) {
duration = parser.getAttributeIntValue(
i, 1000);
}
}
MyFrame myFrame = new MyFrame();
myFrame.bytes = bytes;
myFrame.duration = duration;
myFrames.add(myFrame);
}
} else if (eventType == XmlPullParser.END_TAG) {
} else if (eventType == XmlPullParser.TEXT) {
}
eventType = parser.next();
}
} catch (IOException e) {
e.printStackTrace();
} catch (XmlPullParserException e2) {
// TODO: handle exception
e2.printStackTrace();
}
// Run on UI Thread
new Handler(context.getMainLooper()).post(new Runnable() {
@Override
public void run() {
if (onDrawableLoadedListener != null) {
onDrawableLoadedListener.onDrawableLoaded(myFrames);
}
}
});
}
}).run();
}
// 4
private static void animateRawManually(List<MyFrame> myFrames,
ImageView imageView, Runnable onComplete) {
animateRawManually(myFrames, imageView, onComplete, 0);
}
// 5
private static void animateRawManually(final List<MyFrame> myFrames,
final ImageView imageView, final Runnable onComplete,
final int frameNumber) {
final MyFrame thisFrame = myFrames.get(frameNumber);
if (frameNumber == 0) {
thisFrame.drawable = new BitmapDrawable(imageView.getContext()
.getResources(), BitmapFactory.decodeByteArray(
thisFrame.bytes, 0, thisFrame.bytes.length));
} else {
MyFrame previousFrame = myFrames.get(frameNumber - 1);
((BitmapDrawable) previousFrame.drawable).getBitmap().recycle();
previousFrame.drawable = null;
previousFrame.isReady = false;
}
imageView.setImageDrawable(thisFrame.drawable);
new Handler().postDelayed(new Runnable() {
@Override
public void run() {
// Make sure ImageView hasn't been changed to a different Image
// in this time
if (imageView.getDrawable() == thisFrame.drawable) {
if (frameNumber + 1 < myFrames.size()) {
MyFrame nextFrame = myFrames.get(frameNumber + 1);
if (nextFrame.isReady) {
// Animate next frame
animateRawManually(myFrames, imageView, onComplete,
frameNumber + 1);
} else {
nextFrame.isReady = true;
}
} else {
if (onComplete != null) {
onComplete.run();
}
}
}
}
}, thisFrame.duration);
// Load next frame
if (frameNumber + 1 < myFrames.size()) {
new Thread(new Runnable() {
@Override
public void run() {
MyFrame nextFrame = myFrames.get(frameNumber + 1);
nextFrame.drawable = new BitmapDrawable(imageView
.getContext().getResources(),
BitmapFactory.decodeByteArray(nextFrame.bytes, 0,
nextFrame.bytes.length));
if (nextFrame.isReady) {
// Animate next frame
animateRawManually(myFrames, imageView, onComplete,
frameNumber + 1);
} else {
nextFrame.isReady = true;
}
}
}).run();
}
}
//第二種方法
/***
* 代碼中控制時間,但不精確
* duration = 1000;
* ****/
public static void animateManuallyFromRawResource(
int animationDrawableResourceId, ImageView imageView,
Runnable onStart, Runnable onComplete, int duration) throws IOException,
XmlPullParserException {
AnimationDrawable animationDrawable = new AnimationDrawable();
XmlResourceParser parser = imageView.getContext().getResources()
.getXml(animationDrawableResourceId);
int eventType = parser.getEventType();
while (eventType != XmlPullParser.END_DOCUMENT) {
if (eventType == XmlPullParser.START_DOCUMENT) {
} else if (eventType == XmlPullParser.START_TAG) {
if (parser.getName().equals("item")) {
Drawable drawable = null;
for (int i = 0; i < parser.getAttributeCount(); i++) {
if (parser.getAttributeName(i).equals("drawable")) {
int resId = Integer.parseInt(parser
.getAttributeValue(i).substring(1));
byte[] bytes = IOUtils.toByteArray(imageView
.getContext().getResources()
.openRawResource(resId));//IOUtils.readBytes
drawable = new BitmapDrawable(imageView
.getContext().getResources(),
BitmapFactory.decodeByteArray(bytes, 0,
bytes.length));
} else if (parser.getAttributeName(i)
.equals("duration")) {
duration = parser.getAttributeIntValue(i, 66);
}
}
animationDrawable.addFrame(drawable, duration);
}
} else if (eventType == XmlPullParser.END_TAG) {
} else if (eventType == XmlPullParser.TEXT) {
}
eventType = parser.next();
}
if (onStart != null) {
onStart.run();
}
animateDrawableManually(animationDrawable, imageView, onComplete, 0);
}
private static void animateDrawableManually(
final AnimationDrawable animationDrawable,
final ImageView imageView, final Runnable onComplete,
final int frameNumber) {
final Drawable frame = animationDrawable.getFrame(frameNumber);
imageView.setImageDrawable(frame);
new Handler().postDelayed(new Runnable() {
@Override
public void run() {
// Make sure ImageView hasn't been changed to a different Image
// in this time
if (imageView.getDrawable() == frame) {
if (frameNumber + 1 < animationDrawable.getNumberOfFrames()) {
// Animate next frame
animateDrawableManually(animationDrawable, imageView,
onComplete, frameNumber + 1);
} else {
// Animation complete
if (onComplete != null) {
onComplete.run();
}
}
}
}
}, animationDrawable.getDuration(frameNumber));
}
}
這裡需要導入jar,
import org.apache.commons.io.IOUtils;
4.然後通過上述類，來調用自己的動畫xml,
MyAnimationDrawable.animateRawManuallyFromXML(R.drawable.anim_search,
search_scale_iv, new Runnable() {
@Override
public void run() {
// TODO onStart
// 動畫開始時回調
log.d("","start");
}
}, new Runnable() {
@Override
public void run() {
// TODO onComplete
// 動畫結束時回調
log.d("","end");
}
});
這樣在使用幀動畫時，可以有效的適度防止內存溢出，誰還有什麼辦法，歡迎交流！
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