如何URLEn code proccess后加载图像 [英] How to load image after URLEncode proccess
问题描述
在我的 onPostExecute
proccess,我用的是越来越图片路径从我的服务器:
字符串图像= c.getString(Constants.TAG_Image);
在字符串图片
我得到的数据是这样的: bertho joris.png 或我的名字bertho.jpg
字符串连接codedURL = URLEn coder.en code(图像,UTF-8);
字符串validImage =http://www.mydomain.com/image/\"+en$c$cdURL;
但是,当我使用 URLEn codeR
功能,我的图片没有出现在列表视图。我使用的是类 ImageLoader的
:
进口的java.io.File;
进口java.io.FileInputStream中;
进口java.io.FileNotFoundException;
进口java.io.FileOutputStream中;
进口的java.io.InputStream;
进口java.io.OutputStream中;
进口java.net.HttpURLConnection中;
进口的java.net.URL;
进口java.util.Collections中;
进口的java.util.Map;
进口java.util.WeakHashMap中;
进口java.util.concurrent.ExecutorService中;
进口java.util.concurrent.Executors;
进口android.app.Activity;
进口android.content.Context;
进口android.graphics.Bitmap;
进口android.graphics.BitmapFactory;
进口android.widget.ImageView;进口com.berthojoris.bacaberita.R;公共类ImageLoader的{ 的MemoryCache的MemoryCache =新的MemoryCache();
FileCache fileCache;
私人地图< ImageView的,字符串> imageViews = Collections.synchronizedMap(新的WeakHashMap< ImageView的,字符串>());
ExecutorService的ExecutorService的; 公共ImageLoader的(上下文的背景下){
fileCache =新FileCache(背景);
ExecutorService的= Executors.newFixedThreadPool(5);
} 最终诠释stub_id = R.drawable.not_found;
公共无效DisplayImage(字符串URL,ImageView的ImageView的)
{
imageViews.put(ImageView的,URL);
位图位图= memoryCache.get(URL);
如果(位图!= NULL)
imageView.setImageBitmap(位图);
其他
{
queuePhoto(URL,ImageView的);
imageView.setImageResource(stub_id);
}
} 私人无效queuePhoto(字符串URL,ImageView的ImageView的)
{
PhotoToLoad P =新PhotoToLoad(URL,ImageView的);
executorService.submit(新PhotosLoader(P));
} 私人位图getBitmap(字符串URL)
{
文件F = fileCache.getFile(URL); //从SD缓存
位图B =去codeFILE(F);
如果(B!= NULL)
返回b; //从网页
尝试{
位图位图= NULL;
URL =图片网址新的URL(网址);
HttpURLConnection的康恩=(HttpURLConnection类)imageUrl.openConnection();
conn.setConnectTimeout(30000);
conn.setReadTimeout(30000);
conn.setInstanceFollowRedirects(真);
InputStream为= conn.getInputStream();
OutputStream的OS =新的FileOutputStream(F);
Utils.CopyStream(是,OS);
os.close();
位=去codeFILE(F);
返回位图;
}赶上(例外前){
ex.printStackTrace();
返回null;
}
} //德$ C $连拍影像的鳞它来减少内存消耗
私人位图德codeFILE(文件f){
尝试{
//德code图像尺寸
BitmapFactory.Options O =新BitmapFactory.Options();
o.inJustDe codeBounds = TRUE;
BitmapFactory.de codeStream(新的FileInputStream(F),空,O); //找到正确的比例值。它应该是2的幂。
最终诠释REQUIRED_SIZE = 70;
INT width_tmp = o.outWidth,height_tmp = o.outHeight;
int标= 1;
而(真){
如果(width_tmp / 2'; REQUIRED_SIZE || height_tmp / 2版; REQUIRED_SIZE)
打破;
width_tmp / = 2;
height_tmp / = 2;
规模* = 2;
} //德code。与inSampleSize
BitmapFactory.Options O2 =新BitmapFactory.Options();
o2.inSampleSize =规模;
返回BitmapFactory.de codeStream(新的FileInputStream(F),空,O2);
}赶上(FileNotFoundException异常五){}
返回null;
} //任务队列
私有类PhotoToLoad
{
公共字符串的URL;
公共ImageView的ImageView的;
公共PhotoToLoad(字符串U,ImageView的我){
URL = U;
ImageView的= I;
}
} 类PhotosLoader实现Runnable {
PhotoToLoad photoToLoad;
PhotosLoader(PhotoToLoad photoToLoad){
this.photoToLoad = photoToLoad;
} @覆盖
公共无效的run(){
如果(imageViewReused(photoToLoad))
返回;
BMP位图= getBitmap(photoToLoad.url);
memoryCache.put(photoToLoad.url,BMP);
如果(imageViewReused(photoToLoad))
返回;
BitmapDisplayer BD =新BitmapDisplayer(BMP,photoToLoad);
活动一=(活动)photoToLoad.imageView.getContext();
a.runOnUiThread(BD);
}
} 布尔imageViewReused(PhotoToLoad photoToLoad){
字符串标记= imageViews.get(photoToLoad.imageView);
如果(标记== NULL ||!tag.equals(photoToLoad.url))
返回true;
返回false;
} //用在UI线程来显示位图
类BitmapDisplayer实现Runnable
{
位图位图;
PhotoToLoad photoToLoad;
公共BitmapDisplayer(位图B,PhotoToLoad P){位= B; photoToLoad = P;}
公共无效的run()
{
如果(imageViewReused(photoToLoad))
返回;
如果(位图!= NULL)
photoToLoad.imageView.setImageBitmap(位图);
其他
photoToLoad.imageView.setImageResource(stub_id);
}
} 公共无效clearCache(){
memoryCache.clear();
fileCache.clear();
}}
我的问题:
- 为什么我的画不出来的列表视图?
- 有没有少用这种方式来显示图像?
- 什么我需要我的所有照片都习惯于出现?
我用这个类,它是工作。
您调用该函数( loader.DisplayImage(URL,ImageView的)
)的 onPostExecute
功能异步
..类?
如果它的确定,然后检查你的图片URL(请写出图像URL日志和控制它,因为我犯了那个错误一次)。
In my onPostExecute
proccess, I was getting Image Path from my server using :
String image = c.getString(Constants.TAG_Image);
In the string image
I get the data like this : bertho joris.png or my name bertho.jpg
String encodedURL = URLEncoder.encode(image,"UTF-8");
String validImage = "http://www.mydomain.com/image/"+encodedURL;
But when I use the URLEncoder
function, my images do not appear on the listview. I use a class ImageLoader
:
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.Collections;
import java.util.Map;
import java.util.WeakHashMap;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import android.app.Activity;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.widget.ImageView;
import com.berthojoris.bacaberita.R;
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);
}
final int stub_id = R.drawable.not_found;
public void DisplayImage(String url, ImageView imageView)
{
imageViews.put(imageView, url);
Bitmap bitmap=memoryCache.get(url);
if(bitmap!=null)
imageView.setImageBitmap(bitmap);
else
{
queuePhoto(url, imageView);
imageView.setImageResource(stub_id);
}
}
private void queuePhoto(String url, ImageView imageView)
{
PhotoToLoad p=new PhotoToLoad(url, imageView);
executorService.submit(new PhotosLoader(p));
}
private 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;
}
}
//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=70;
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=scale;
return BitmapFactory.decodeStream(new FileInputStream(f), null, o2);
} catch (FileNotFoundException e) {}
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();
}
}
My question:
- Why is my picture did not come out on listview?
- Is there less to display the image in this way?
- What do I need to have all my pictures were accustomed to appear?
I used this class and it is working.
Are you calling this function(loader.DisplayImage(url,imageView)
) in onPostExecute
function of Async
.. class?
If it's ok, then check your image URL(please write image URL in log and control it, because I made that mistake one time).
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