我是Android新手。我正在开发一个用于学习新概念的小型Android应用程序。
我正在研究HttpUrlConnection
。我在发出HTTP请求时遇到困难。我正在使用public class MainActivity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
}
});
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}
库来完成我的任务。
到目前为止,我已经创建了以下代码:
MainActivity.java:
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
HttpURLConnection urlConnection = null;
BufferedReader reader = null;
InputStream in = null;
String forecastJsonStr = null;
int resCode = -1;
try {
URL url= new URL("http://api.openweathermap.org/data/2.5/forecast/daily?q=94043&mode=json&units=metric&cnt=7&APPID=XXX");
urlConnection= (HttpURLConnection) url.openConnection();
urlConnection.setRequestMethod("GET");
urlConnection.connect();
resCode=urlConnection.getResponseCode();
if(resCode == HttpURLConnection.HTTP_OK){
in = urlConnection.getInputStream();
}
reader = new BufferedReader(new InputStreamReader(in));
StringBuffer buffer = new StringBuffer();
String line;
while ((line = reader.readLine()) != null) {
buffer.append(line + "\n");
}
if (buffer.length() == 0) {
return null;
}
forecastJsonStr = buffer.toString();
Log.d("responce", forecastJsonStr);
}
catch (IOException e1) {
e1.printStackTrace();
}
//You can ignore the lower portion of the code. I have just created an arraylist of weather and am showing on the android app
String[] data={"Mon 6/23 - Sunny - 31/17",
"Tue 6/24 - Foggy - 21/8",
"Wed 6/25 - Cloudy - 22/17",
"Thurs 6/26 - Rainy - 18/11",
"Fri 6/27 - Foggy - 21/10",
"Sat 6/28 - TRAPPED IN WEATHERSTATION - 23/18",
"Sun 6/29 - Sunny - 20/7"};
List<String> weekForcast = new ArrayList<String>(Arrays.asList(data));
ArrayAdapter<String> arrayAdapter = new ArrayAdapter<String>(getActivity(), R.layout.list_item_forecast, R.id.list_item_forecast_textview,weekForcast);
View rootView = inflater.inflate(R.layout.fragment_main,container,false);
ListView listView = (ListView) rootView.findViewById(R.id.listview_forcast);
listView.setAdapter(arrayAdapter);
return rootView;
}
MainActivityFragment.java
> Process: com.example.android.udacityclass, PID: 20766 02-05
> 16:54:20.695 20766-20766/com.example.android.udacityclass
> E/AndroidRuntime: java.lang.RuntimeException: Unable to start activity
> ComponentInfo{com.example.android.udacityclass/com.example.android.udacityclass.MainActivity}:
> android.view.InflateException: Binary XML file line #1: Error
> inflating class fragment 02-05 16:54:20.695
> 20766-20766/com.example.android.udacityclass E/AndroidRuntime: at
> android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2358)
> 02-05 16:54:20.695 20766-20766/com.example.android.udacityclass
> E/AndroidRuntime: at
> android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2420)
> 02-05 16:54:20.695 20766-20766/com.example.android.udacityclass
> E/AndroidRuntime: at
> android.app.ActivityThread.access$900(ActivityThread.java:154) 02-05
> 16:54:20.695 20766-20766/com.example.android.udacityclass
> E/AndroidRuntime: at
> android.app.ActivityThread$H.handleMessage(ActivityThread.java:1321)
> 02-05 16:54:20.695 20766-20766/com.example.android.udacityclass
> E/AndroidRuntime: at
> android.os.Handler.dispatchMessage(Handler.java:102) 02-05
> 16:54:20.695 20766-20766/com.example.android.udacityclass
> E/AndroidRuntime: at android.os.Looper.loop(Looper.java:135) 02-05
> 16:54:20.695 20766-20766/com.example.android.udacityclass
> E/AndroidRuntime: at
> android.app.ActivityThread.main(ActivityThread.java:5292) 02-05
> 16:54:20.695 20766-20766/com.example.android.udacityclass
> E/AndroidRuntime: at java.lang.reflect.Method.invoke(Native
> Method) 02-05 16:54:20.695
> 20766-20766/com.example.android.udacityclass E/AndroidRuntime: at
> java.lang.reflect.Method.invoke(Method.java:372) 02-05 16:54:20.695
> 20766-20766/com.example.android.udacityclass E/AndroidRuntime: at
> com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:904)
> 02-05 16:54:20.695 20766-20766/com.example.android.udacityclass
> E/AndroidRuntime: at
> com.android.internal.os.ZygoteInit.main(ZygoteInit.java:699) 02-05
> 16:54:20.695 20766-20766/com.example.android.udacityclass
> E/AndroidRuntime: Caused by: android.view.InflateException: Binary
> XML file line #1: Error inflating class fragment 02-05 16:54:20.695
> 20766-20766/com.example.android.udacityclass E/AndroidRuntime: at
> android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:763)
> 02-05 16:54:20.695 20766-20766/com.example.android.udacityclass
> E/AndroidRuntime: at
> android.view.LayoutInflater.parseInclude(LayoutInflater.java:892)
> 02-05 16:54:20.695 20766-20766/com.example.android.udacityclass
> E/AndroidRuntime: at
> android.view.LayoutInflater.rInflate(LayoutInflater.java:802) 02-05
> 16:54:20.695 20766-20766/com.example.android.udacityclass
> E/AndroidRuntime: at
> android.view.LayoutInflater.inflate(LayoutInflater.java:504) 02-05
> 16:54:20.695 20766-20766/com.example.android.udacityclass
> E/AndroidRuntime: at
> android.view.LayoutInflater.inflate(LayoutInflater.java:414) 02-05
> 16:54:20.695 20766-20766/com.example.android.udacityclass
> E/AndroidRuntime: at
> android.view.LayoutInflater.inflate(LayoutInflater.java:365) 02-05
> 16:54:20.695 20766-20766/com.example.android.udacityclass
> E/AndroidRuntime: at
> android.support.v7.app.AppCompatDelegateImplV7.setContentView(AppCompatDelegateImplV7.java:257)
> 02-05 16:54:20.695 20766-20766/com.example.android.udacityclass
> E/AndroidRuntime: at
> android.support.v7.app.AppCompatActivity.setContentView(AppCompatActivity.java:109)
> 02-05 16:54:20.695 20766-20766/com.example.android.udacityclass
> E/AndroidRuntime: at
> com.example.android.udacityclass.MainActivity.onCreate(MainActivity.java:17)
> 02-05 16:54:20.695 20766-20766/com.example.android.udacityclass
> E/AndroidRuntime: at
> android.app.Activity.performCreate(Activity.java:5990) 02-05
> 16:54:20.695 20766-20766/com.example.android.udacityclass
> E/AndroidRuntime: at
> android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1106)
> 02-05 16:54:20.695 20766-20766/com.example.android.udacityclass
> E/AndroidRuntime: at
> android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2311)
> 02-05 16:54:20.695 20766-20766/com.example.android.udacityclass
> E/AndroidRuntime: at
> android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2420)
> 02-05 16:54:20.695 20766-20766/com.example.android.udacityclass
> E/AndroidRuntime: at
> android.app.ActivityThread.access$900(ActivityThread.java:154) 02-05
> 16:54:20.695 20766-20766/com.example.android.udacityclass
> E/AndroidRuntime: at
> android.app.ActivityThread$H.handleMessage(ActivityThread.java:1321)
> 02-05 16:54:20.695 20766-20766/com.example.android.udacityclass
> E/AndroidRuntime: at
> android.os.Handler.dispatchMessage(Handler.java:102) 02-05
> 16:54:20.695 20766-20766/com.example.android.udacityclass
> E/AndroidRuntime: at android.os.Looper.loop(Looper.java:135)
> 02-05 16:54:20.695 20766-20766/com.example.android.udacityclass
> E/AndroidRuntime: at
> android.app.ActivityThread.main(ActivityThread.java:5292) 02-05
> 16:54:20.695 20766-20766/com.example.android.udacityclass
> E/AndroidRuntime: at java.lang.reflect.Method.invoke(Native
> Method) 02-05 16:54:20.695
> 20766-20766/com.example.android.udacityclass E/AndroidRuntime: at
> java.lang.reflect.Method.invoke(Method.java:372)
每当我尝试运行代码时,都会收到以下错误:
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.12.0/jquery.min.js"></script>
<input type="text" id="name">
<p id="result"></p>
任何人都可以帮我解决此错误。此外,有人可以帮我找到android中调试错误的引用。非常感谢
答案 0 :(得分:2)
看起来您正在主线程上发出请求,请使用Asynctask&lt;&gt;在后台线程中发出请求。查看此链接以了解如何使用,在doInbackground方法中创建您的http请求。
http://programmerguru.com/android-tutorial/android-asynctask-example/
有关Android后台进程的更多详细信息,请查看此链接 http://www.vogella.com/tutorials/AndroidBackgroundProcessing/article.html 希望这有帮助。