AsyncTask#1:执行doInBackground()时发生错误
问题描述:
我正在用Jsoup开发应用程序。问题是,当我在Getters的帮助下从其他课程调用它时,它不起作用。但是当我在单一活动中调用它时,它正在运行。我无法找到它为什么无法正常工作,因为它应该。 以下是包含所有活动的logCat文件。AsyncTask#1:执行doInBackground()时发生错误
logcat的
11-14 20:16:52.063: E/AndroidRuntime(1871): FATAL EXCEPTION: AsyncTask #1
11-14 20:16:52.063: E/AndroidRuntime(1871): java.lang.RuntimeException: An error occured while executing doInBackground()
11-14 20:16:52.063: E/AndroidRuntime(1871): at android.os.AsyncTask$3.done(AsyncTask.java:299)
11-14 20:16:52.063: E/AndroidRuntime(1871): at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:352)
11-14 20:16:52.063: E/AndroidRuntime(1871): at java.util.concurrent.FutureTask.setException(FutureTask.java:219)
11-14 20:16:52.063: E/AndroidRuntime(1871): at java.util.concurrent.FutureTask.run(FutureTask.java:239)
11-14 20:16:52.063: E/AndroidRuntime(1871): at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:230)
11-14 20:16:52.063: E/AndroidRuntime(1871): at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1080)
11-14 20:16:52.063: E/AndroidRuntime(1871): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:573)
11-14 20:16:52.063: E/AndroidRuntime(1871): at java.lang.Thread.run(Thread.java:856)
11-14 20:16:52.063: E/AndroidRuntime(1871): Caused by: java.lang.IllegalArgumentException: Must supply a valid URL
11-14 20:16:52.063: E/AndroidRuntime(1871): at org.jsoup.helper.Validate.notEmpty(Validate.java:102)
11-14 20:16:52.063: E/AndroidRuntime(1871): at org.jsoup.helper.HttpConnection.url(HttpConnection.java:57)
11-14 20:16:52.063: E/AndroidRuntime(1871): at org.jsoup.helper.HttpConnection.connect(HttpConnection.java:27)
11-14 20:16:52.063: E/AndroidRuntime(1871): at org.jsoup.Jsoup.connect(Jsoup.java:73)
11-14 20:16:52.063: E/AndroidRuntime(1871): at com.example.frgbdf.jsoupAct$Parsee.doInBackground(jsoupAct.java:30)
11-14 20:16:52.063: E/AndroidRuntime(1871): at com.example.frgbdf.jsoupAct$Parsee.doInBackground(jsoupAct.java:1)
11-14 20:16:52.063: E/AndroidRuntime(1871): at android.os.AsyncTask$2.call(AsyncTask.java:287)
11-14 20:16:52.063: E/AndroidRuntime(1871): at java.util.concurrent.FutureTask.run(FutureTask.java:234)
11-14 20:16:52.063: E/AndroidRuntime(1871): ... 4 more
MainActivity
public class MainActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Intent i = new Intent(getApplicationContext(), LineGraph.class);
startActivity(i);
}
}
LineGraph
public class LineGraph extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
jsoupAct mJsoupAct = new jsoupAct();
String parseStrings;
parseStrings = mJsoupAct.getOutput();
Log.d("xstring", parseStrings + "");
}
}
jsoupAct
public class jsoupAct extends Activity {
String output = "00";
String url;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
url = "www.google.com";
}
public void mExecute() {
new Parsee().execute();
}
public class Parsee extends AsyncTask<String, String, String> {
protected String doInBackground(String... params) {
try {
Document doc = Jsoup.connect(url).get();
String body = doc.body().text();
output = body.toString();
} catch (IOException e) {
e.printStackTrace();
}
return output;
}
@Override
protected void onPostExecute(String result) {
super.onPostExecute(output);
}
}
public String getOutput() {
mExecute();
return output;
}
public void setOutput(String output) {
this.output = output;
}
}
答
你正在一个字符串本地到jsoupAct activity
指定URL
。如果您尝试从其他活动进行访问,该字符串将为空。为了解决其移动字符串中的AsyncTask类中,它会工作
或空的构造函数添加到jsonAct
活动和其分配的url
值。 onCreate()
仅当使用“http”而不是“www”使用startActivity()
答
您已经回答了自己的问题:
Caused by: java.lang.IllegalArgumentException: Must supply a valid URL
at org.jsoup.helper.Validate.notEmpty(Validate.java:102)
at org.jsoup.helper.HttpConnection.url(HttpConnection.java:57)
at org.jsoup.helper.HttpConnection.connect(HttpConnection.java:27)
at org.jsoup.Jsoup.connect(Jsoup.java:73)
at com.example.frgbdf.jsoupAct$Parsee.doInBackground(jsoupAct.java:30)
at com.example.frgbdf.jsoupAct$Parsee.doInBackground(jsoupAct.java:1)
at android.os.AsyncTask$2.call(AsyncTask.java:287)
at java.util.concurrent.FutureTask.run(FutureTask.java:234)
... 4 more
MB网址开始活动时才会被调用? – Suvitruf
尝试使用'http:// www.google.com'添加http部分 – Coderji