Java 安卓4.0中的类没有响应-适用于2.3及以下版本
我有一个类GetWeather.java，它从API获取天气数据。它是从我的应用程序的主活动通过一个单独的线程定期调用的。线程点击GetWeather类并将返回的数据发布到TextView 在任何一种情况下，GetWeather类中返回的数据的System.out.println都表明数据确实在返回 下面是GetWeather.java：Java 安卓4.0中的类没有响应-适用于2.3及以下版本,java,android,Java,Android,我有一个类GetWeather.java，它从API获取天气数据。它是从我的应用程序的主活动通过一个单独的线程定期调用的。线程点击GetWeather类并将返回的数据发布到TextView 在任何一种情况下，GetWeather类中返回的数据的System.out.println都表明数据确实在返回 下面是GetWeather.java： import java.io.BufferedReader; import java.io.InputStream; import java.io.Input
import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import android.net.Uri;
import android.util.Log;
public class GetWeather {
InputStream is = null;
JSONArray jArray = null;
JSONObject json_data = new JSONObject();
String result = "";
String strTemp = "";
String strWindSpeed = "";
String strWindDir = "";
String strVisibility = "";
String strPosition = "";
public static final Uri KEY_121 = Uri.parse("http://api.worldweatheronline.com/free/v1/weather.ashx");
String strWeatherApiKey = "REMOVED";
public GetWeather(String Location) {
strPosition = Location;
}
public void returnWeather() {
try {
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost(KEY_121 + "?key="
+ strWeatherApiKey + "&q=" + strPosition + "&format=json");
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());
}
// parse json data
try {
JSONObject object = new JSONObject(result);
JSONObject weather = object.getJSONObject("data");
JSONArray current_conditions = weather
.getJSONArray("current_condition");
for (int i = 0; i < current_conditions.length(); i++) {
JSONObject object1 = (JSONObject) current_conditions.get(i);
strTemp = object1.getString("temp_C");
strWindSpeed = object1.getString("windspeedMiles");
strWindDir = object1.getString("winddir16Point");
strVisibility = object1.getString("visibility");
// Testing output
System.out.println(strTemp);
System.out.println(strWindSpeed);
System.out.println(strWindDir);
System.out.println(strVisibility);
}
} catch (JSONException e) {
Log.e("log_tag", "Error parsing data " + e.toString());
}
}
}
FroYoICSJellyBean提前感谢尝试使用类似这样的异步任务 在你的主要活动中
public class GetWeather extends AsyncTask<Void, Integer, Void> {
public GetWeather(Activity activity) {
this.activity = activity;
context = activity;
dialog = new ProgressDialog(context);
}
/** progress dialog to show user that the backup is processing. */
private ProgressDialog dialog;
/** application context. */
private Activity activity;
private Context context;
protected void onPreExecute() {
// TODO Auto-generated method stub
super.onPreExecute();
}
@Override
protected Void doInBackground(Void... params) {
// TODO Auto-generated method stub
GetWeather weather = new GetWeather(strPosition);
weather.returnWeather();
return null;
}
@Override
protected void onPostExecute(Void result) {
// TODO Auto-generated method stub
super.onPostExecute(result);
tvConsole
.append("Weather Update\n-------------------\n\nCurrent Temp (C): "
+ weather.strTemp
+ "C\n"
+ "Wind is out of the "
+ weather.strWindDir
+ " at "
+ weather.strWindSpeed
+ " MPH\n"
+ "Visibility is "
+ weather.strVisibility
+ " miles\n\n");
// Auto-scroll textview
// Does not function on Android 4.0+
final Layout layout = tvConsole.getLayout();
if (layout != null) {
int scrollDelta = layout.getLineBottom(tvConsole
.getLineCount() - 1)
- tvConsole.getScrollY()
- tvConsole.getHeight();
if (scrollDelta > 0)
tvConsole.scrollBy(0, scrollDelta);
}
}
}
尝试像这样使用异步任务 在你的主要活动中
public class GetWeather extends AsyncTask<Void, Integer, Void> {
public GetWeather(Activity activity) {
this.activity = activity;
context = activity;
dialog = new ProgressDialog(context);
}
/** progress dialog to show user that the backup is processing. */
private ProgressDialog dialog;
/** application context. */
private Activity activity;
private Context context;
protected void onPreExecute() {
// TODO Auto-generated method stub
super.onPreExecute();
}
@Override
protected Void doInBackground(Void... params) {
// TODO Auto-generated method stub
GetWeather weather = new GetWeather(strPosition);
weather.returnWeather();
return null;
}
@Override
protected void onPostExecute(Void result) {
// TODO Auto-generated method stub
super.onPostExecute(result);
tvConsole
.append("Weather Update\n-------------------\n\nCurrent Temp (C): "
+ weather.strTemp
+ "C\n"
+ "Wind is out of the "
+ weather.strWindDir
+ " at "
+ weather.strWindSpeed
+ " MPH\n"
+ "Visibility is "
+ weather.strVisibility
+ " miles\n\n");
// Auto-scroll textview
// Does not function on Android 4.0+
final Layout layout = tvConsole.getLayout();
if (layout != null) {
int scrollDelta = layout.getLineBottom(tvConsole
.getLineCount() - 1)
- tvConsole.getScrollY()
- tvConsole.getHeight();
if (scrollDelta > 0)
tvConsole.scrollBy(0, scrollDelta);
}
}
}
您不能从后台线程中触摸ui线程中的任何内容，要使用处理程序进行此操作，请初始化后台线程并向其传递处理程序对象。当数据到达时，使用处理程序向ui发送消息。在ui中，当来自后台线程的消息出现时，只需更新视图。您不能从后台线程接触ui线程中的任何内容，为此，请使用处理程序初始化后台线程，并向其传递处理程序对象。当数据到达时，使用处理程序向ui发送消息。在ui中，当来自后台线程的消息出现时，只需更新视图。如果您可以放置任何日志，请！！看起来您可能正在尝试从UI线程以外的其他内容更新UI？@ChrisStratton yep。事实上，我从来没有想到过这个问题。如果你能把任何日志放进去，请！！看起来您可能正在尝试从UI线程以外的其他内容更新UI？@ChrisStratton yep。事实上，我从来没有想到过这个问题。谢谢你。今晚我会研究一下，看看是否可以将其合并到现有的项目中。谢谢。今晚我将对此进行调查，看看是否可以将其合并到现有项目中。
new GetWeather(Mainactivity.this).execute();