从Android中JSONString中存储的URL加载ImageView中的图像
我有一个从Android中JSONString中存储的URL加载ImageView中的图像,android,json,imageview,Android,Json,Imageview,我有一个JSON字符串，比如一个名字和一个Url。我需要将名称提取到文本视图中，并在图像视图中提取和显示图像。 下面是上述场景的代码 public static final String JSON_STRING="{\"WebImages\":{\"Imagename\":\"image_name\",\"imageurl\":http://www.example.com/image/example.png}}"; 我需要在我创建的TextView中显示名称，然后从该url获取图像并显示在
JSON文本视图图像视图 public static final String JSON_STRING="{\"WebImages\":{\"Imagename\":\"image_name\",\"imageurl\":http://www.example.com/image/example.png}}";
我需要在我创建的
TextViewImageviewGSONJSONObject object = new JSONObject("your strnig");
JSONObject webimages = object.getJSONObject("WebImages");
String imageName = webimages.getString("image_name")
String imageUrl = webimages.getString("imageurl")
使用Universal Image Loader以非常快速和平滑的方式加载图像首先使用Gson解析Json并将url作为字符串获取，然后您可以使用UniversalImageLoader库（它进行异步图像下载，非常易于使用）
您可以像这样提取图像名称和url
public static final String JSON_STRING="{\"WebImages\":{\"Imagename\":\"image_name\",\"imageurl\":http://www.example.com/image/example.png}}";
JSONObject jsonObject = new JSONObject(JSON_STRING);
JSONObject webImages = jsonObject.getJSONObject("WebImages");
String imageName = webImages.getString("Imagename");
String imageUrl = webImages.getString("imageurl");
myTextView.setText（imageName）Picasso.with(context).load(imageUrl).into(imageView);
你可以这样做
public static final String JSON_STRING="{"WebImages":{"Imagename":"image_name","imageurl":http://www.example.com/image/example.png}}";
private ImageLoader _ImageLoader;
try {
JSONObject _jObj = new JSONObject(JSON_STRING);
JSONObject _jSubObj = _jObj .getJSONObject("WebImages");
String _imageName= _jSubObj.getString("Imagename");
YOUR_TEXTVIEW.setText(_imageName);
String _imageURL= _jSubObj.getString("imageurl");
_ImageLoader = new ImageLoader(CURRENT_ACTIVITY.this);
_ImageLoader.DisplayImage(_imageURL,
R.drawable.ic_launcher, YOUR_IMAGEVIEW);
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
public class ImageLoader {
MemoryCache memoryCache=new MemoryCache();
FileCache fileCache;
private Map<ImageView, String> imageViews=Collections.synchronizedMap(new WeakHashMap<ImageView, String>());
ExecutorService executorService;
public ImageLoader(Context context){
fileCache=new FileCache(context);
executorService=Executors.newFixedThreadPool(5);
}
int stub_id = R.drawable.ic_launcher;
public void DisplayImage(String url, int loader, ImageView imageView)
{
try {
stub_id = loader;
imageViews.put(imageView, url);
Bitmap bitmap=memoryCache.get(url);
if(bitmap!=null)
imageView.setImageBitmap(bitmap);
else
{
queuePhoto(url, imageView);
imageView.setImageResource(loader);
}
} catch (Exception e) {
e.printStackTrace();
}
}
private void queuePhoto(String url, ImageView imageView)
{
PhotoToLoad p=new PhotoToLoad(url, imageView);
executorService.submit(new PhotosLoader(p));
}
public Bitmap getBitmap(String url)
{
File f=fileCache.getFile(url);
//from SD cache
Bitmap b = decodeFile(f);
if(b!=null)
return b;
//from web
try {
Bitmap bitmap=null;
URL imageUrl = new URL(url);
HttpURLConnection conn = (HttpURLConnection)imageUrl.openConnection();
conn.setConnectTimeout(30000);
conn.setReadTimeout(30000);
conn.setInstanceFollowRedirects(true);
InputStream is=conn.getInputStream();
OutputStream os = new FileOutputStream(f);
Utils.CopyStream(is, os);
os.close();
bitmap = decodeFile(f);
return bitmap;
} catch (Exception ex){
ex.printStackTrace();
return null;
}
}
public Bitmap getFacebookImage(String userId) {
// TODO Auto-generated method stub
Bitmap bitmap = null;
try {
HttpGet httpRequest = new HttpGet(
URI.create(userId));
HttpClient httpclient = new DefaultHttpClient();
HttpResponse response = (HttpResponse) httpclient
.execute(httpRequest);
HttpEntity entity = response.getEntity();
BufferedHttpEntity bufHttpEntity = new BufferedHttpEntity(
entity);
bitmap = BitmapFactory
.decodeStream(bufHttpEntity
.getContent());
httpRequest.abort();
} catch (Exception e) {
e.printStackTrace();
}
return bitmap;
}
//decodes image and scales it to reduce memory consumption
private Bitmap decodeFile(File f){
try {
//decode image size
BitmapFactory.Options o = new BitmapFactory.Options();
o.inJustDecodeBounds = true;
BitmapFactory.decodeStream(new FileInputStream(f),null,o);
//Find the correct scale value. It should be the power of 2.
// final int REQUIRED_SIZE=200;
// int width_tmp=o.outWidth, height_tmp=o.outHeight;
// int scale=1;
// while(true){
// if(width_tmp/2<REQUIRED_SIZE || height_tmp/2<REQUIRED_SIZE)
//break;
//width_tmp/=2;
//height_tmp/=2;
// scale*=2;
// }
//decode with inSampleSize
BitmapFactory.Options o2 = new BitmapFactory.Options();
o2.inSampleSize=1;
return BitmapFactory.decodeStream(new FileInputStream(f), null, o2);
} catch (FileNotFoundException e) {
}catch (Exception e) {
e.printStackTrace();
}
return null;
}
//Task for the queue
private class PhotoToLoad
{
public String url;
public ImageView imageView;
public PhotoToLoad(String u, ImageView i){
url=u;
imageView=i;
}
}
class PhotosLoader implements Runnable {
PhotoToLoad photoToLoad;
PhotosLoader(PhotoToLoad photoToLoad){
this.photoToLoad=photoToLoad;
}
@Override
public void run() {
if(imageViewReused(photoToLoad))
return;
Bitmap bmp=getBitmap(photoToLoad.url);
memoryCache.put(photoToLoad.url, bmp);
if(imageViewReused(photoToLoad))
return;
BitmapDisplayer bd=new BitmapDisplayer(bmp, photoToLoad);
Activity a=(Activity)photoToLoad.imageView.getContext();
a.runOnUiThread(bd);
}
}
boolean imageViewReused(PhotoToLoad photoToLoad){
String tag=imageViews.get(photoToLoad.imageView);
if(tag==null || !tag.equals(photoToLoad.url))
return true;
return false;
}
//Used to display bitmap in the UI thread
class BitmapDisplayer implements Runnable
{
Bitmap bitmap;
PhotoToLoad photoToLoad;
public BitmapDisplayer(Bitmap b, PhotoToLoad p){bitmap=b;photoToLoad=p;}
public void run()
{
if(imageViewReused(photoToLoad))
return;
if(bitmap!=null)
photoToLoad.imageView.setImageBitmap(bitmap);
else
photoToLoad.imageView.setImageResource(stub_id);
}
}
public void clearCache() {
memoryCache.clear();
fileCache.clear();
}
}
public static final String JSON_String=“{”WebImages:{”Imagename:“image_name”，“imageurl”：http://www.example.com/image/example.png}}";
私有ImageLoader _ImageLoader；
试一试{
JSONObject_jObj=新的JSONObject（JSON_字符串）；
JSONObject _jSubObj=_jObj.getJSONObject（“WebImages”）；
字符串_imageName=_jSubObj.getString（“imageName”）；
您的_TEXTVIEW.setText（_imageName）；
字符串_imageURL=_jSubObj.getString（“imageURL”）；
_ImageLoader=新的ImageLoader（当前_活动。此）；
_ImageLoader.DisplayImage（\u imageURL，
R.drawable.ic_启动器，您的_图像视图）；
}捕获（JSONException e）{
//TODO自动生成的捕捉块
e、 printStackTrace（）；
}
公共类图像加载器{
MemoryCache MemoryCache=新的MemoryCache（）；
文件缓存文件缓存；
private Map ImageView=Collections.synchronizedMap（新的WeakHashMap（））；
执行服务执行服务；
公共图像加载器（上下文）{
fileCache=新的fileCache（上下文）；
executorService=Executors.newFixedThreadPool（5）；
}
int stub_id=R.drawable.ic_启动器；
public void DisplayImage（字符串url、整型加载器、ImageView）
{
试一试{
存根id=装载机；
put（imageView，url）；
位图位图=memoryCache.get（url）；
if（位图！=null）
设置图像位图（位图）；
其他的
{
队列照片（url、imageView）；
setImageResource（加载程序）；
}
}捕获（例外e）{
e、 printStackTrace（）；
}
}
私有void队列照片（字符串url，ImageView）
{
PhotoToLoad p=新的PhotoToLoad（url，imageView）；
executorService.submit（新的PhotoLoader（p））；
}
公共位图getBitmap（字符串url）
{
文件f=fileCache.getFile（url）；
//从SD缓存
位图b=解码文件（f）；
如果（b！=null）
返回b；
//从网络
试一试{
位图=空；
URL imageUrl=新URL（URL）；
HttpURLConnection conn=（HttpURLConnection）imageUrl.openConnection（）；
连接设置连接超时（30000）；
连接设置读取超时（30000）；
conn.setInstanceFollowRedirects（真）；
InputStream is=conn.getInputStream（）；
OutputStream os=新文件OutputStream（f）；
Utils.CopyStream（is，os）；
os.close（）；
位图=解码文件（f）；
返回位图；
}捕获（例外情况除外）{
例如printStackTrace（）；
返回null；
}
}
公共位图getFacebookImage（字符串用户ID）{
//TODO自动生成的方法存根
位图=空；
试一试{
HttpGet httpRequest=新的HttpGet(
create（userId））；
HttpClient HttpClient=新的DefaultHttpClient（）；
HttpResponse响应=（HttpResponse）httpclient
.执行（httpRequest）；
HttpEntity=response.getEntity（）；
BufferedHttpEntity bufHttpEntity=新BufferedHttpEntity(
实体）；
位图=位图工厂
.decodeStream（bufHttpEntity
.getContent（））；
httpRequest.abort（）；
}捕获（例外e）{
e、 printStackTrace（）；
}
返回位图；
}
//对图像进行解码和缩放以减少内存消耗
私有位图解码文件（文件f）{
试一试{
//解码图像大小
BitmapFactory.Options o=新的BitmapFactory.Options（）；
o、 inJustDecodeBounds=true；
解码流（新的FileInputStream（f），null，o）；
//找到正确的刻度值。它应该是2的幂。
//所需的最终int_尺寸=200；
//内部宽度=o.向外宽度，高度=o.向外高度；
//int标度=1；
//while（true）{
//如果（width_tmp/2any method without GSON？请尝试{JSONObject emp=（new JSONObject（JSON_STRING））.getJSONObject（“WebImages”）；STRING ImageName=emp.getString（“ImageName”）；text1.setText（ImageName
public static final String JSON_STRING="{"WebImages":{"Imagename":"image_name","imageurl":http://www.example.com/image/example.png}}";
private ImageLoader _ImageLoader;
try {
JSONObject _jObj = new JSONObject(JSON_STRING);
JSONObject _jSubObj = _jObj .getJSONObject("WebImages");
String _imageName= _jSubObj.getString("Imagename");
YOUR_TEXTVIEW.setText(_imageName);
String _imageURL= _jSubObj.getString("imageurl");
_ImageLoader = new ImageLoader(CURRENT_ACTIVITY.this);
_ImageLoader.DisplayImage(_imageURL,
R.drawable.ic_launcher, YOUR_IMAGEVIEW);
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
public class ImageLoader {
MemoryCache memoryCache=new MemoryCache();
FileCache fileCache;
private Map<ImageView, String> imageViews=Collections.synchronizedMap(new WeakHashMap<ImageView, String>());
ExecutorService executorService;
public ImageLoader(Context context){
fileCache=new FileCache(context);
executorService=Executors.newFixedThreadPool(5);
}
int stub_id = R.drawable.ic_launcher;
public void DisplayImage(String url, int loader, ImageView imageView)
{
try {
stub_id = loader;
imageViews.put(imageView, url);
Bitmap bitmap=memoryCache.get(url);
if(bitmap!=null)
imageView.setImageBitmap(bitmap);
else
{
queuePhoto(url, imageView);
imageView.setImageResource(loader);
}
} catch (Exception e) {
e.printStackTrace();
}
}
private void queuePhoto(String url, ImageView imageView)
{
PhotoToLoad p=new PhotoToLoad(url, imageView);
executorService.submit(new PhotosLoader(p));
}
public Bitmap getBitmap(String url)
{
File f=fileCache.getFile(url);
//from SD cache
Bitmap b = decodeFile(f);
if(b!=null)
return b;
//from web
try {
Bitmap bitmap=null;
URL imageUrl = new URL(url);
HttpURLConnection conn = (HttpURLConnection)imageUrl.openConnection();
conn.setConnectTimeout(30000);
conn.setReadTimeout(30000);
conn.setInstanceFollowRedirects(true);
InputStream is=conn.getInputStream();
OutputStream os = new FileOutputStream(f);
Utils.CopyStream(is, os);
os.close();
bitmap = decodeFile(f);
return bitmap;
} catch (Exception ex){
ex.printStackTrace();
return null;
}
}
public Bitmap getFacebookImage(String userId) {
// TODO Auto-generated method stub
Bitmap bitmap = null;
try {
HttpGet httpRequest = new HttpGet(
URI.create(userId));
HttpClient httpclient = new DefaultHttpClient();
HttpResponse response = (HttpResponse) httpclient
.execute(httpRequest);
HttpEntity entity = response.getEntity();
BufferedHttpEntity bufHttpEntity = new BufferedHttpEntity(
entity);
bitmap = BitmapFactory
.decodeStream(bufHttpEntity
.getContent());
httpRequest.abort();
} catch (Exception e) {
e.printStackTrace();
}
return bitmap;
}
//decodes image and scales it to reduce memory consumption
private Bitmap decodeFile(File f){
try {
//decode image size
BitmapFactory.Options o = new BitmapFactory.Options();
o.inJustDecodeBounds = true;
BitmapFactory.decodeStream(new FileInputStream(f),null,o);
//Find the correct scale value. It should be the power of 2.
// final int REQUIRED_SIZE=200;
// int width_tmp=o.outWidth, height_tmp=o.outHeight;
// int scale=1;
// while(true){
// if(width_tmp/2<REQUIRED_SIZE || height_tmp/2<REQUIRED_SIZE)
//break;
//width_tmp/=2;
//height_tmp/=2;
// scale*=2;
// }
//decode with inSampleSize
BitmapFactory.Options o2 = new BitmapFactory.Options();
o2.inSampleSize=1;
return BitmapFactory.decodeStream(new FileInputStream(f), null, o2);
} catch (FileNotFoundException e) {
}catch (Exception e) {
e.printStackTrace();
}
return null;
}
//Task for the queue
private class PhotoToLoad
{
public String url;
public ImageView imageView;
public PhotoToLoad(String u, ImageView i){
url=u;
imageView=i;
}
}
class PhotosLoader implements Runnable {
PhotoToLoad photoToLoad;
PhotosLoader(PhotoToLoad photoToLoad){
this.photoToLoad=photoToLoad;
}
@Override
public void run() {
if(imageViewReused(photoToLoad))
return;
Bitmap bmp=getBitmap(photoToLoad.url);
memoryCache.put(photoToLoad.url, bmp);
if(imageViewReused(photoToLoad))
return;
BitmapDisplayer bd=new BitmapDisplayer(bmp, photoToLoad);
Activity a=(Activity)photoToLoad.imageView.getContext();
a.runOnUiThread(bd);
}
}
boolean imageViewReused(PhotoToLoad photoToLoad){
String tag=imageViews.get(photoToLoad.imageView);
if(tag==null || !tag.equals(photoToLoad.url))
return true;
return false;
}
//Used to display bitmap in the UI thread
class BitmapDisplayer implements Runnable
{
Bitmap bitmap;
PhotoToLoad photoToLoad;
public BitmapDisplayer(Bitmap b, PhotoToLoad p){bitmap=b;photoToLoad=p;}
public void run()
{
if(imageViewReused(photoToLoad))
return;
if(bitmap!=null)
photoToLoad.imageView.setImageBitmap(bitmap);
else
photoToLoad.imageView.setImageResource(stub_id);
}
}
public void clearCache() {
memoryCache.clear();
fileCache.clear();
}
}