内存溢出应对:把图片固定大小赋值给bitmap

主题:
//将绝对路径转换为Bitmap,动态计算inSampleSize限制图片大小此处大小为128*128 RGB_565(默认为8888)下为 2.7K
public static Bitmap getFixedSizeImg(String filePath){
Bitmap bitmap = null;
BitmapFactory.Options opts = new BitmapFactory.Options();
opts.inJustDecodeBounds = true;
opts.inPreferredConfig = Bitmap.Config.RGB_565;
opts.inPurgeable = true;
opts.inInputShareable = true;
BitmapFactory.decodeFile(filePath, opts);

opts.inSampleSize = computeSampleSize(opts, -1, 128*128);
opts.inJustDecodeBounds = false;

try {
bitmap = BitmapFactory.decodeFile(filePath, opts);
}catch (Exception e) {
// TODO: handle exception
}
return bitmap;
}
//计算inSampleSize
public static int computeSampleSize(BitmapFactory.Options options, int minSideLength, int maxNumOfPixels) {
int initialSize = computeInitialSampleSize(options, minSideLength, maxNumOfPixels);
int roundedSize;
if (initialSize <= 8) {
roundedSize = 1;
while (roundedSize < initialSize) {
roundedSize <<= 1;
}
} else {
roundedSize = (initialSize + 7) / 8 * 8;
}
return roundedSize;
}
//计算inSampleSize
private static int computeInitialSampleSize(BitmapFactory.Options options,int minSideLength, int maxNumOfPixels) {
double w = options.outWidth;
double h = options.outHeight;
int lowerBound = (maxNumOfPixels == -1) ? 1 : (int) Math.ceil(Math.sqrt(w * h / maxNumOfPixels));
int upperBound = (minSideLength == -1) ? 128 :(int) Math.min(Math.floor(w / minSideLength), Math.floor(h / minSideLength));
if (upperBound < lowerBound) {
// return the larger one when there is no overlapping zone.
return lowerBound;
}
if ((maxNumOfPixels == -1) && (minSideLength == -1)) {
return 1;
} else if (minSideLength == -1) {
return lowerBound;
} else {
return upperBound;
}
}
主题结束
重写Activity此方法可查看app内存状态
@Override
public void onTrimMemory(int level) {
super.onTrimMemory(level);
switch (level) {
case TRIM_MEMORY_RUNNING_MODERATE:
LongLog.loge("你的app正在运行并且不会被列为可杀死的");
break;
case TRIM_MEMORY_RUNNING_LOW:
LongLog.loge("你的app正在运行且没有被列为可杀死的");
break;
case TRIM_MEMORY_RUNNING_CRITICAL:
LongLog.loge("你的app仍在运行，但是系统已经把LRU Cache中的大多数进程都已经杀死");
break;
case TRIM_MEMORY_BACKGROUND:
LongLog.loge("系统正运行于低内存");
break;
case TRIM_MEMORY_MODERATE:
LongLog.loge(" 系统正运行于低内存状态并且你的进程已经已经接近LRU名单的中部位置");
break;
case TRIM_MEMORY_COMPLETE:
LongLog.loge("系统正运行与低内存的状态并且你的进程正处于LRU名单中最容易被杀掉的位置");
break;
}
}