0
我读过几十个帖子关于这个，并试图尽可能多的解决方案，下载图像的数组，但我似乎无法得到任何工作。我从JSON响应中填充listview，其中包括许多（有时超过100）行。每一行都有一个关联的（和不同的）图像。Android的 - 无法设置异步线程从互联网
在性能测试中，当我没有下载/显示图像，从JSON响应134点的行的处理，并在小于2秒显示。真棒！但是，当我将图像下载/显示恢复时，花费了大约10年的时间。
这是非常明显，我需要使用一个后台线程下载图像，但是每次我在网上找到的解决方案是不成功的（假设我的一部分某些错误在这一点）。
我想我有一个想法，我需要在后台处理图像，但我不完全知道如何去设置它。
现在，图像（连同所有其他数据）被加载到一个数组中。现在每个图像都以内联方式下载，因此令人难以置信的性能噩梦。
这里是我的主要活动类的一些代码摘录...
InputStream is = null;
//http post
try{
postQuery = "my api path";
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost(postQuery);
HttpResponse response = httpclient.execute(httppost);
HttpEntity entity = response.getEntity();
is = entity.getContent();
}catch(Exception e){
Log.e("log_tag", "Error in http connection "+e.toString());
}
//convert response to string
try{
BufferedReader reader = new BufferedReader(new InputStreamReader(is,"iso-8859-1"),8);
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
is.close();
result=sb.toString();
}catch(Exception e){
Log.e("log_tag", "Error converting result "+e.toString());
}
m_bottles = new ArrayList<Bottles>();
this.m_adapter = new BottleAdapter(this, R.layout.bottlelistimagelayout, m_bottles);
setListAdapter(this.m_adapter);
viewBottles = new Runnable(){
public void run() {
getBottles();
}
};
Thread thread = new Thread(null, viewBottles, "MagentoBackground");
thread.start();
m_ProgressDialog = ProgressDialog.show(SpiritsBottles.this,
"Please wait...", "Retrieving data ...", true);
public class Bottle{
public String name_abbrArray;
}
private void getBottles(){
try{
JSONObject row = new JSONObject(result);
array = row.getJSONArray("bottles");
m_bottles = new ArrayList<Bottles>();
for(int i=0;i<array.length();i++){
row = array.getJSONObject(i);
bottleID = row.getInt("id");
name_abbr = row.getString("name_abbr");
bottlePicture = row.getString("image");
Bottles o = new Bottles();
o.setbottleID(bottleID);
o.setname_abbr(name_abbr);
o.setbottlePicture(bottlePicture);
m_bottles.add(o);
Log.i("ARRAY", "" + m_bottles.size() + " - " + i + "/" + array.length()+"m_bottles size = "+m_bottles.size());
}
} catch (Exception e) {
Log.e("PROC - bottleid = "+bottleNamesMap.get("bottlePicture2"), e.getMessage());
}
runOnUiThread(returnRes);
}
private Runnable returnRes = new Runnable() {
public void run() {
if(m_bottles != null && m_bottles.size() > 0){
m_adapter.notifyDataSetChanged();
for(int i=0;i<m_bottles.size();i++)
m_adapter.add(m_bottles.get(i));
}
m_ProgressDialog.dismiss();
m_adapter.notifyDataSetChanged();
}
};
private class BottleAdapter extends ArrayAdapter<Bottles> {
private ArrayList<Bottles> items;
public BottleAdapter(Context context, int textViewResourceId, ArrayList<Bottles> items) {
super(context, textViewResourceId, items);
this.items = items;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
View v = convertView;
if (v == null) {
LayoutInflater vi = (LayoutInflater)getSystemService(Context.LAYOUT_INFLATER_SERVICE);
v = vi.inflate(R.layout.bottlelistimagelayout, null);
}
Bottles o = items.get(position);
if (o != null) {
final TextView bottlenametv = (TextView) v.findViewById(R.id.bottlename);
final ImageView iv = (ImageView) v.findViewById(R.id.icon);
if (bottlenametv != null) {
bottlenametv.setText(o.getname_abbr());
bottlenametv.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
Intent intent = new Intent(getApplicationContext(), SingleBottleDisplay.class);
intent.putExtra("name", bottlenametv.getText());
startActivityForResult(intent,0);
}
});
}
if(iv != null){
iv.setImageBitmap(o.getbottlePicture());
iv.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
Intent intent = new Intent(getApplicationContext(), SingleBottleDisplay.class);
intent.putExtra("name", bottlenametv.getText());
startActivityForResult(intent,0);
}
});
}
}
return v;
}
}
这里是我的瓶类在那里我目前下载的每一行的图像在线（这是我的性能问题）。
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.net.MalformedURLException;
import java.net.URL;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.util.Log;
public class Bottles {
private int bottleID;
private String name_abbr;
private Bitmap bottlePicture;
public int getbottleID() {
return bottleID;
}
public void setbottleID(Integer bottleID) {
this.bottleID = bottleID;
}
public String getname_abbr() {
return name_abbr;
}
public void setname_abbr(String name_abbr) {
this.name_abbr = name_abbr;
}
public void setbottlePicture(String bottlePicture) throws MalformedURLException, IOException {
BitmapFactory.Options options = new BitmapFactory.Options();
options.inSampleSize=6;
Bitmap bitmap = BitmapFactory.decodeStream((InputStream)new URL(bottlePicture).getContent(), null, options);
this.bottlePicture = bitmap;
}
public Bitmap getbottlePicture() {
return bottlePicture;
}
}
我真的，真的希望有人能帮助我走出这是我在我的穷途末路，几乎出来的咖啡... :)