我尝试使用异步任务解码从互联网下载的图像。问题是图像有时会加载,有时则不加载。 URL上的图像始终存在。
这是我的asycn任务:
private class JSONIconWeatherTask extends AsyncTask<String, Void, byte[]> {
@Override
protected byte[] doInBackground(String... params) {
byte[] data = null;
try {
// Let's retrieve the icon
data = ( (new WeatherHttpClient()).getImage(params[0]));
} catch (Exception e) {
e.printStackTrace();
}
return data;
}
@Override
protected void onPostExecute(byte[] data) {
super.onPostExecute(data);
if (data != null) {
Bitmap img = BitmapFactory.decodeByteArray(data, 0, data.length);
iconWeather.setImageBitmap(img);
}
}
}
这是我的日志:
09-29 15:53:14.590:W / System.err(14373):java.net.ConnectException:无法连接到/127.0.0.1(端口81):连接失败:ECONNREFUSED(连接被拒绝) 09-29 15:53:14.590:W / System.err(14373):at libcore.io.IoBridge.connect(IoBridge.java:114) 09-29 15:53:14.590:W / System.err(14373):at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:192) 09-29 15:53:14.590:W / System.err(14373):at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:459) 09-29 15:53:14.590:W / System.err(14373):at java.net.Socket.connect(Socket.java:842) 09-29 15:53:14.590:W / System.err(14373):at libcore.net.http.HttpConnection。(HttpConnection.java:76) 09-29 15:53:14.590:W / System.err(14373):at libcore.net.http.HttpConnection。(HttpConnection.java:50) 09-29 15:53:14.590:W / System.err(14373):at libcore.net.http.HttpConnection $ Address.connect(HttpConnection.java:340) 09-29 15:53:14.590:W / System.err(14373):at libcore.net.http.HttpConnectionPool.get(HttpConnectionPool.java:87) 09-29 15:53:14.590:W / System.err(14373):at libcore.net.http.HttpConnection.connect(HttpConnection.java:128) 09-29 15:53:14.590:W / System.err(14373):at libcore.net.http.HttpEngine.openSocketConnection(HttpEngine.java:316) 09-29 15:53:14.590:W / System.err(14373):at libcore.net.http.HttpEngine.connect(HttpEngine.java:311) 09-29 15:53:14.590:W / System.err(14373):at libcore.net.http.HttpEngine.sendSocketRequest(HttpEngine.java:290) 09-29 15:53:14.590:W / System.err(14373):at libcore.net.http.HttpEngine.sendRequest(HttpEngine.java:240) 09-29 15:53:14.590:W / System.err(14373):at libcore.net.http.HttpURLConnectionImpl.getResponse(HttpURLConnectionImpl.java:282) 09-29 15:53:14.590:W / System.err(14373):at libcore.net.http.HttpURLConnectionImpl.getInputStream(HttpURLConnectionImpl.java:177) 09-29 15:53:14.590:W / System.err(14373):at com.example.weatherforecast.WeatherHttpClient.getImage(WeatherHttpClient.java:116) 09-29 15:53:14.590:W / System.err(14373):at com.example.weatherforecast.MainActivity $ JSONForecastWeatherTask.doInBackground(MainActivity.java:187) 09-29 15:53:14.590:W / System.err(14373):at com.example.weatherforecast.MainActivity $ JSONForecastWeatherTask.doInBackground(MainActivity.java:1) 09-29 15:53:14.590:W / System.err(14373):在android.os.AsyncTask $ 2.call(AsyncTask.java:287) 09-29 15:53:14.590:W / System.err(14373):at java.util.concurrent.FutureTask.run(FutureTask.java:234) 09-29 15:53:14.590:W / System.err(14373):在android.os.AsyncTask $ SerialExecutor $ 1.run(AsyncTask.java:230) 09-29 15:53:14.590:W / System.err(14373):at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1080) 09-29 15:53:14.600:W / System.err(14373):at java.util.concurrent.ThreadPoolExecutor $ Worker.run(ThreadPoolExecutor.java:573) 09-29 15:53:14.600:W / System.err(14373):at java.lang.Thread.run(Thread.java:856) 09-29 15:53:14.600:W / System.err(14373):引起:libcore.io.ErrnoException:连接失败:ECONNREFUSED(拒绝连接) 09-29 15:53:14.600:W / System.err(14373):at libcore.io.Posix.connect(Native Method) 09-29 15:53:14.600:W / System.err(14373):at libcore.io.BlockGuardOs.connect(BlockGuardOs.java:85) 09-29 15:53:14.600:W / System.err(14373):at libcore.io.IoBridge.connectErrno(IoBridge.java:127) 09-29 15:53:14.600:W / System.err(14373):at libcore.io.IoBridge.connect(IoBridge.java:112)
答案 0 :(得分:0)
“拒绝连接”表示您尝试连接的服务器(此处为:localhost)没有任何内容在您尝试连接的端口上侦听(此处:81)。
名称localhost是指代码运行的设备,即android设备或模拟器。除非您还在同一设备上运行接受端口81上的连接的应用程序,否则您将连接到错误的地址。
如果您在开发计算机上运行服务器并尝试从模拟器连接,则应使用10.0.2.2而不是localhost。见why do we use 10.0.2.2 to connect to local web server instead of using computer ip address in android client