android 异步加载图片
[代码] AsyncImageLoader.javapackage cn.com.mzba.service;import java.io.InputStream;
import java.lang.ref.SoftReference;
import java.net.URL;
import java.util.HashMap;
import android.graphics.drawable.Drawable;
import android.os.Handler;
import android.os.Message;
import android.widget.ImageView;
/**
* 实现图片的异步载入显示
* @author kandanle
*
*/
public class AsyncImageLoader {
/**
* 软引用对象，在响应内存需要时，由不良回收器决定是否清除此对象。软引用对象最常用于实现内存敏感的缓存。
*/
private HashMap<String, SoftReference<Drawable>> imageCache;
public AsyncImageLoader(){
imageCache = new HashMap<String, SoftReference<Drawable>>();
}
public Drawable loadDrawable(final String imageUrl,final ImageView imageView,final ImageCallback imagecallback){
if(imageCache.containsKey(imageUrl)){
//从缓存中读取人人
SoftReference<Drawable> softReference = imageCache.get(imageUrl);
Drawable drawable = softReference.get();
if(drawable != null){
return drawable;
}
}
final Handler handler = new Handler(){
@Override
public void handleMessage(Message msg) {
super.handleMessage(msg);
imagecallback.imageLoaded((Drawable)msg.obj, imageView, imageUrl);
}
};
new Thread(){
public void run() {
Drawable drawable = loadImageFromUrl(imageUrl);
imageCache.put(imageUrl, new SoftReference<Drawable>(drawable));
Message message = handler.obtainMessage(0, drawable);
handler.sendMessage(message);
}
}.start();
return null;
}
public static Drawable loadImageFromUrl(String urlPath){
URL url;
InputStream is = null;
try{
url = new URL(urlPath);
is = (InputStream)url.getContent();
}catch(Exception e){
e.printStackTrace();
}
Drawable drawable = Drawable.createFromStream(is, "src");
return drawable;
}
}
[代码] ImageCallback.javapackage cn.com.mzba.service;
import android.graphics.drawable.Drawable;
import android.widget.ImageView;
public inte**ce ImageCallback {
public void imageLoaded(Drawable imageDrawable,ImageView imageView, String imageUrl);
}
Drawable drawable = asyncImageLoader.loadDrawable(weiboInfo.getUserIcon(), viewUserIcon, new ImageCallback() {
@Override
public void imageLoaded(Drawable imageDrawable, ImageView imageView,String imageUrl) {
imageView.setImageDrawable(imageDrawable);
}
});
if(drawable == null){
viewUserIcon.setImageResource(R.drawable.portrait);
}else{
viewUserIcon.setImageDrawable(drawable);
}
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