图片三级缓存↙↙↙↙↙
public class MemonryCacleUtiles {
private final LruCachememorycacle;
public MemonryCacleUtiles() {
//应用程序使用的最大内存
int maxmemopry = (int) Runtime.getRuntime().maxMemory();
//缓存的大小
int cacsesize = maxmemopry /8;
//默认返回的图片数量
memorycacle =new LruCache(cacsesize){
@Override
protected int sizeOf(String key, Bitmap value) {
return value.getByteCount();
}
};
}
//图片保存到缓存
public void saveBitmapToMemoryCache (String path,Bitmap bitmap){
memorycacle.put(path,bitmap);
}
//从缓存中获取图片
public Bitmap getBitmapToMemoryCacle (String path) {
return memorycacle.get(path);
}
}
public class DiskCacleUtiles {
private Stringpath = Environment.getExternalStorageDirectory().getAbsolutePath()+"/NewPhto";
//保存到SD卡中
public void saveBitmapToDiskCache (String pathurl,Bitmap bitmap)throws UnsupportedEncodingException {
//对图片进行MD5加密
String filename = MD5Utils.getEncryption(pathurl);
//创建一个文件
File file =new File(path,filename);
//将图片保存到文件中
try {
bitmap.compress(Bitmap.CompressFormat.JPEG,100,new FileOutputStream(file));
}catch (Exception e) {
e.printStackTrace();
}
}
//获取磁盘中的图片
public Bitmap getBitmapCacle (String pathurl)throws UnsupportedEncodingException {
String filername = MD5Utils.getEncryption(pathurl);
File file =new File(path,filername);
Bitmap bitmap =null;
try {
BitmapFactory.decodeStream(new FileInputStream(file));
}catch (FileNotFoundException e) {
try {
bitmap = BitmapFactory.decodeStream(new FileInputStream(file));
}catch (FileNotFoundException e1) {
}
}
return bitmap;
}
}
MD5加密
public static String getEncryption(String originString)
throws UnsupportedEncodingException {
String result ="";
if (originString !=null) {
try {
// 指定加密的方式为MD5
MessageDigest md = MessageDigest.getInstance("MD5");
// 进行加密运算
byte bytes[] = md.digest(originString.getBytes("ISO8859-1"));
for (int i =0; i < bytes.length; i++) {
// 将整数转换成十六进制形式的字符串 这里与0xff进行与运算的原因是保证转换结果为32位
String str = Integer.toHexString(bytes[i] &0xFF);
if (str.length() ==1) {
str +="F";
}
result += str;
}
}catch (NoSuchAlgorithmException e) {
e.printStackTrace();
}
}
return result;
}
网络
private DiskCacleUtilesdiskCacleUtiles;
private MemonryCacleUtilesmemonryCacleUtiles;
public NewsWork(DiskCacleUtiles diskCacleUtiles, MemonryCacleUtiles memonryCacleUtiles) {
this.diskCacleUtiles = diskCacleUtiles;
this.memonryCacleUtiles = memonryCacleUtiles;
}
public void exeute (String path, ImageView imageView) {
BitMapTask bitMapTask =new BitMapTask();
bitMapTask.execute(path,imageView);
}
class BitMapTaskextends AsyncTask{
private Stringurlpath;
private ImageViewimageView;
private Bitmapbitmap;
@Override
protected Bitmap doInBackground(Object... objects) {
urlpath = (String) objects[0];
imageView = ((ImageView) objects[1]);
try {
bitmap = downloadbitmap();
}catch (Exception e) {
}
return bitmap;
}
@Override
protected void onPostExecute(Bitmap bitmap) {
if (bitmap !=null) {
//设置图片
imageView.setImageBitmap(bitmap);
memonryCacleUtiles.saveBitmapToMemoryCache(urlpath,bitmap);
try {
diskCacleUtiles.saveBitmapToDiskCache(urlpath,bitmap);
}catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
}
super.onPostExecute(bitmap);
}
private Bitmap downloadbitmap()throws Exception {
URL url =new URL(urlpath);
HttpURLConnection connection = (HttpURLConnection) url.openConnection();
if (connection.getResponseCode() ==200) {
InputStream inputStream = connection.getInputStream();
BitmapFactory.Options options =new BitmapFactory.Options();
//获取原图的大小
options.inJustDecodeBounds=true;
//设置压缩的比例
options.inSampleSize=2;
//再次解析图片设置为false
options.inJustDecodeBounds=false;
Bitmap bitmap = BitmapFactory.decodeStream(inputStream,null,options);
return bitmap;
}
return null;
}
}
public class BitMapUtils {
private MemonryCacleUtilesmemonryCacleUtiles;
private DiskCacleUtilesdiskCacleUtiles;
private NewsWorknewsWork;
public BitMapUtils() {
this.memonryCacleUtiles =new MemonryCacleUtiles();
this.diskCacleUtiles =new DiskCacleUtiles();
this.newsWork =new NewsWork(diskCacleUtiles,memonryCacleUtiles);
}
public void showBitmap(String path, ImageView imageView) {
Bitmap bitmap =memonryCacleUtiles.getBitmapToMemoryCacle(path);
if (bitmap !=null) {
imageView.setImageBitmap(bitmap);
return;
}
try {
bitmap =diskCacleUtiles.getBitmapCacle(path);
}catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
if (bitmap !=null) {
imageView.setImageBitmap(bitmap);
return;
}
newsWork.exeute(path,imageView);
}
