安卓中关于图片从网络获取，压缩，上传，下载，缩略图，缓存的一些处理总结（四）

来源：互联网发布：苹果手机信号增强软件编辑：程序博客网时间：2024/06/05 18:30

这里根绝网上的一些文章写了一个工具类  pictureSize 一般写成1080*1920  这个数值越大图片越清晰 加载需要的内存越多   请大家根据情况自行设定    这里2个方法 一个是针对网上URL 一个是本地path

public static Bitmap downloadImgByUrl(String imgUrl, int pictureSize) {        BufferedInputStream is = null;        HttpURLConnection conn = null;        try {            URL url = new URL(imgUrl);            conn = (HttpURLConnection) url.openConnection();            is = new BufferedInputStream(conn.getInputStream());            is.mark(is.available());        } catch (IOException e) {            e.printStackTrace();        }        Bitmap bitmap = null;        BitmapFactory.Options opts = new BitmapFactory.Options();        //2.为位图设置100K的缓存        opts.inTempStorage = new byte[100 * 1024];        //3.设置位图颜色显示优化方式        opts.inPreferredConfig = Bitmap.Config.RGB_565;        //4.设置图片可以被回收，创建Bitmap用于存储Pixel的内存空间在系统内存不足时可以被回收        opts.inPurgeable = true;        //6.设置解码位图的尺寸信息        opts.inInputShareable = true;        opts.inJustDecodeBounds = true;//        bitmap=BitmapFactory.decodeStream(is, null, opts);        opts.inSampleSize = computeSampleSize(opts, -1, pictureSize);        opts.inJustDecodeBounds = false;        try {            bitmap = BitmapFactory.decodeStream(is, null, opts);            is.reset();            conn.disconnect();        } catch (Exception e) {            // TODO: handle exception        }        return bitmap;    }    public static Bitmap revitionImageSize(String filePath, int pictureSize) {        Bitmap bitmap = null;        BitmapFactory.Options opts = new BitmapFactory.Options();        //2.为位图设置100K的缓存        opts.inTempStorage = new byte[100 * 1024];        //3.设置位图颜色显示优化方式        opts.inPreferredConfig = Bitmap.Config.RGB_565;        //4.设置图片可以被回收，创建Bitmap用于存储Pixel的内存空间在系统内存不足时可以被回收        opts.inPurgeable = true;        //6.设置解码位图的尺寸信息        opts.inInputShareable = true;        opts.inJustDecodeBounds = true;        bitmap=BitmapFactory.decodeFile(filePath, opts);        opts.inSampleSize = computeSampleSize(opts, -1, pictureSize);        opts.inJustDecodeBounds = false;        try {            bitmap = BitmapFactory.decodeFile(filePath, opts);        } catch (Exception e) {            // TODO: handle exception        }        return bitmap;    }    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;    }    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;        }    }

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