public class MainActivity extends Activity {
时间=private String url “https://cache.yisu.com/upload/information/20200311/46/200000.jpg”;
@Override
protected void onCreate (Bundle savedInstanceState), {
super.onCreate (savedInstanceState);
setContentView (R.layout.activity_main);
testTask ();
}
public void testTask () {
DownloadPicTask task =, new DownloadPicTask ();
url=task.imgPath ;
task.img =, (ImageView), findViewById (R.id.p_w_picpathView1);
task.execute (url);
}
} //任务类
package com.example.task;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.util.EntityUtils;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.AsyncTask;
import android.util.Log;
import android.widget.ImageView;
public , class DownloadPicTask extends AsyncTask<字符串,整数,,String> {
public String imgPath;,
private byte[],数据;
public ImageView img;
protected void onPrepareExecute () {
Log.v(“任务”,“onPrepareExecute”);
super.onPreExecute ();
}//,doInBackground方法内部执行后台任务,不可在此方法内修改UI
@Override
protected String doInBackground(字符串…,arg0), {//,TODO Auto-generated method 存根
Log.v(“任务”,“doInBackground ”, +, arg0);
HttpClient HttpClient =, new DefaultHttpClient ();
HttpGet HttpGet =, new HttpGet (imgPath);
HttpResponse HttpResponse =,空;
try {
时间=httpResponse httpClient.execute (httpGet);
.getStatusCode if (httpResponse.getStatusLine () (),==, 200), {
时间=data EntityUtils.toByteArray (httpResponse
.getEntity ());
}
},catch (Exception e), {
e.printStackTrace ();
}
return 零;
}//,onProgressUpdate方法用于更新进度信息
@Override
protected void onProgressUpdate(整数…,进展),{
Log.v(“任务”,“onProgressUpdate”);
super.onProgressUpdate(进展);
}//,onPostExecute方法用于在执行完后台任务后更新UI,显示结果
@Override
protected void onPostExecute (String 结果),{//,progressDialog.dismiss ();
Log.v(“任务”,“onPostExecute”);
Bitmap bmp=BitmapFactory.decodeByteArray(数据,,0,,data.length);
img.setImageBitmap (bmp);
}//,虚方法用于在取消执行中的任务时更改UI
@Override
protected void 虚(),{
Log.v(“任务”,“虚”);
}
} //. xml中只有一个ImageView控件
