android - Android：FATAL EXCEPTION MAIN .. 应用程序每次都崩溃

Question

我正在尝试制作一个简单的天气 android 应用程序。由于我是 android 新手，所以我在很多地方都面临着问题。而这一次我想我搞砸了我的主要活动和表现。我在这里粘贴整个代码。请在我出错的地方提供宝贵的建议。

主要活动

package com.example.checkweather;

import java.io.IOException;
import java.util.List;
import java.util.Locale;
import java.util.concurrent.ExecutionException;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import android.app.Activity;
import android.content.Context;
import android.graphics.Bitmap;
import android.location.Address;
import android.location.Criteria;
import android.location.Geocoder;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;
import android.widget.TextView;
import android.widget.Toast;


public class MainActivity extends Activity implements LocationListener {
  private TextView latituteField;
  private TextView longitudeField;
  private LocationManager locationManager;
  private TextView mylocation;
  private TextView Entry1, Entry2, Entry3, Entry4, Entry5;
  private JSONObject jobject1, jobject2, jarray, tempjobject;
  private JSONArray temparray;
  private String provider, string, city;
  private String[] maximum = new String[5];
  private String[] minimum = new String[5];
  private String[] conditions = new String[5];

/** Called when the activity is first created. */

  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    latituteField = (TextView) findViewById(R.id.TextView02);
    longitudeField = (TextView) findViewById(R.id.TextView04);
    mylocation = (TextView) findViewById(R.id.TextView06);
    Entry1 = (TextView) findViewById(R.id.day1);
    Entry2 = (TextView) findViewById(R.id.day2);
    Entry3 = (TextView) findViewById(R.id.day3);
    Entry4 = (TextView) findViewById(R.id.day4);
    Entry5 = (TextView) findViewById(R.id.day5);

    // Get the location manager
    locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
    // Define the criteria how to select the locatioin provider -> use
    // default
    Criteria criteria = new Criteria();
    provider = locationManager.getBestProvider(criteria, false);
    Location location = locationManager.getLastKnownLocation(provider);

    // Initialize the location fields
    if (location != null) {
      System.out.println("Provider " + provider + " has been selected.");
      onLocationChanged(location);
    } else {
      latituteField.setText("Location not available");
      longitudeField.setText("Location not available");
    } 
        String result;
        try {
            result = new WeatherHttpClient().execute("http://api.wunderground.com/api/796da11422ba3dc2/forecast10day/q/"+city+".json").get();

            try {
                jobject1 = new JSONObject(result);
            jarray = jobject1.getJSONObject("forecast");
            jobject2 = jarray.getJSONObject("simpleforecast");
            temparray = jobject2.getJSONArray("forecastday");
            string = result;

            for(int i=0;i<5;i++){
                 tempjobject= temparray.getJSONObject(i);
                maximum[i] =tempjobject.getString("high");
                minimum[i] = tempjobject.getString("low");
                conditions[i] = tempjobject.getString("conditions");
            }           
            JSONObject j1 = new JSONObject(maximum[0]);
            JSONObject j2 = new JSONObject(minimum[0]);
            JSONObject j3 = new JSONObject(maximum[1]);
            JSONObject j4 = new JSONObject(minimum[1]);
            JSONObject j5 = new JSONObject(maximum[2]);
            JSONObject j6 = new JSONObject(minimum[2]);
            JSONObject j7 = new JSONObject(maximum[3]);
            JSONObject j8 = new JSONObject(minimum[3]);
            JSONObject j9 = new JSONObject(maximum[4]);
            JSONObject j10 = new JSONObject(minimum[4]);

            Entry1.setText("Maximum" + j1.getString("fahrenheit")+"°F"  + "Minimum" + j2.getString("fahrenheit")+"°F "+ conditions[0]);
            Entry2.setText("Maximum" + j3.getString("fahrenheit")+"°F"  + "Minimum" + j4.getString("fahrenheit")+"°F "+ conditions[1]);
            Entry3.setText("Maximum" + j5.getString("fahrenheit")+"°F"  + "Minimum" + j6.getString("fahrenheit")+"°F "+ conditions[2]);
            Entry4.setText("Maximum" + j7.getString("fahrenheit")+"°F"  + "Minimum" + j8.getString("fahrenheit")+"°F "+ conditions[3]);
            Entry5.setText("Maximum" + j9.getString("fahrenheit")+"°F"  + "Minimum" + j10.getString("fahrenheit")+"°F "+ conditions[4]);

            } catch (JSONException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }

            } catch (InterruptedException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (ExecutionException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
  }

  /* Request updates at startup */

  @Override
  protected void onResume() {
    super.onResume();
    locationManager.requestLocationUpdates(provider, 400, 1, this);
  }

  /* Remove the locationlistener updates when Activity is paused */
  @Override
  protected void onPause() {
    super.onPause();
    locationManager.removeUpdates(this);
  }


  @Override
  public void onLocationChanged(Location location) {
    int lat = (int) (location.getLatitude());
    int lng = (int) (location.getLongitude());
    latituteField.setText(String.valueOf(lat));
    longitudeField.setText(String.valueOf(lng));
    Geocoder geoCoder1 = new Geocoder(getBaseContext(), Locale.getDefault());
    try {
        String add = "";
        List<Address> addresses;
        List<Address> fromLocation;

            fromLocation = (List<Address>) geoCoder1.getFromLocation(lat,lng, 1);

        addresses = fromLocation;
        if (addresses.size() > 0) 
        {
            for (int i=0; i<((android.location.Address) addresses.get(0)).getMaxAddressLineIndex();i++)
                add += ((android.location.Address) addresses.get(0)).getAddressLine(i) + "\n";
        }
        mylocation.setText(String.valueOf(add));  
        Bundle extras = getIntent().getExtras();
        if (extras != null) {
            city = extras.getString("ZipCode");
        }
        else{

            city = ((android.location.Address) addresses.get(0)).getPostalCode();
        }
        Toast.makeText(getBaseContext(), city, Toast.LENGTH_SHORT).show();

  } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }}



  @Override
  public void onStatusChanged(String provider, int status, Bundle extras) {
    // TODO Auto-generated method stub

  }

  @Override
  public void onProviderEnabled(String provider) {
    Toast.makeText(this, "Enabled new provider " + provider,
        Toast.LENGTH_SHORT).show();

  }

  @Override
  public void onProviderDisabled(String provider) {
    Toast.makeText(this, "Disabled provider " + provider,
        Toast.LENGTH_SHORT).show();
  }
}

XML 文件：

    <?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >

    <LinearLayout
        android:id="@+id/linearLayout1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="40dip"
        android:orientation="horizontal" >

        <TextView
            android:id="@+id/TextView01"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginLeft="10dip"
            android:layout_marginRight="5dip"
            android:text="@string/Lati"
            android:textSize="20sp" >
        </TextView>

        <TextView
            android:id="@+id/TextView02"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:textSize="20sp" >
        </TextView>
    </LinearLayout>

    <LinearLayout
        android:id="@+id/linearLayout2"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" >

        <TextView
            android:id="@+id/TextView03"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginLeft="10dip"
            android:layout_marginRight="5dip"
            android:text="@string/Longi"
            android:textSize="20sp" >
        </TextView>

        <TextView
            android:id="@+id/TextView04"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"

            android:textSize="20sp" >
        </TextView>
    </LinearLayout>

    <LinearLayout
        android:id="@+id/linearLayout3"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" >

        <TextView
            android:id="@+id/TextView05"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginLeft="10dip"
            android:layout_marginRight="5dip"
            android:text="@string/Locati"
            android:textSize="20sp" >
        </TextView>

        <TextView
            android:id="@+id/TextView06"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:textSize="20sp" >
        </TextView>
    </LinearLayout>
    <TextView
              android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_marginLeft="10dip"
                android:layout_marginRight="5dip"
                android:paddingTop="15dip"
                android:text="@string/d1"
                android:textSize="20sp" >
            </TextView>

            <TextView
                android:id="@+id/day1"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="xxxxxxx"
                android:textSize="20sp" >
        </TextView>

            <TextView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_marginLeft="10dip"
                android:layout_marginRight="5dip"
                android:paddingTop="15dip"
                android:text="@string/d2"
                android:textSize="20sp" >
            </TextView>

            <TextView
                android:id="@+id/day2"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="yyyyyyyyy"
                android:textSize="20sp" >
        </TextView>

            <TextView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_marginLeft="10dip"
                android:layout_marginRight="5dip"
                android:paddingTop="15dip"
                android:text="@string/d3"
                android:textSize="20sp" >
            </TextView>

            <TextView
                android:id="@+id/day3"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="zzzzzzz"
                android:textSize="20sp" >
        </TextView>

                <TextView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_marginLeft="10dip"
                android:layout_marginRight="5dip"
                android:paddingTop="15dip"
                android:text="@string/d4"
                android:textSize="20sp" >
            </TextView>

            <TextView
                android:id="@+id/day4"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="zzzzzsdfdszz"
                android:textSize="20sp" >
        </TextView>

                <TextView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_marginLeft="10dip"
                android:layout_marginRight="5dip"
                android:paddingTop="15dip"
                android:text="@string/d5"
                android:textSize="20sp" >
            </TextView>

            <TextView
                android:id="@+id/day5"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="fdsadfsdf"
                android:textSize="20sp" >
        </TextView>
      </LinearLayout>

原木猫：

10-17 20:02:20.235: D/ActivityThread(17009): setTargetHeapUtilization:0.25
10-17 20:02:20.235: D/ActivityThread(17009): setTargetHeapIdealFree:8388608
10-17 20:02:20.245: D/ActivityThread(17009): setTargetHeapConcurrentStart:2097152
10-17 20:02:20.395: I/System.out(17009): Provider network has been selected.
10-17 20:02:20.745: W/dalvikvm(17009): threadid=1: thread exiting with uncaught exception (group=0x41e90438)
10-17 20:02:20.745: E/AndroidRuntime(17009): FATAL EXCEPTION: main
10-17 20:02:20.745: E/AndroidRuntime(17009): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.checkweather/com.example.checkweather.MainActivity}: java.lang.NullPointerException
10-17 20:02:20.745: E/AndroidRuntime(17009):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2110)
10-17 20:02:20.745: E/AndroidRuntime(17009):    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2135)
10-17 20:02:20.745: E/AndroidRuntime(17009):    at android.app.ActivityThread.access$700(ActivityThread.java:143)
10-17 20:02:20.745: E/AndroidRuntime(17009):    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1241)
10-17 20:02:20.745: E/AndroidRuntime(17009):    at android.os.Handler.dispatchMessage(Handler.java:99)
10-17 20:02:20.745: E/AndroidRuntime(17009):    at android.os.Looper.loop(Looper.java:137)
10-17 20:02:20.745: E/AndroidRuntime(17009):    at android.app.ActivityThread.main(ActivityThread.java:4950)
10-17 20:02:20.745: E/AndroidRuntime(17009):    at java.lang.reflect.Method.invokeNative(Native Method)
10-17 20:02:20.745: E/AndroidRuntime(17009):    at java.lang.reflect.Method.invoke(Method.java:511)
10-17 20:02:20.745: E/AndroidRuntime(17009):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1004)
10-17 20:02:20.745: E/AndroidRuntime(17009):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:771)
10-17 20:02:20.745: E/AndroidRuntime(17009):    at dalvik.system.NativeStart.main(Native Method)
10-17 20:02:20.745: E/AndroidRuntime(17009): Caused by: java.lang.NullPointerException
10-17 20:02:20.745: E/AndroidRuntime(17009):    at org.json.JSONTokener.nextCleanInternal(JSONTokener.java:116)
10-17 20:02:20.745: E/AndroidRuntime(17009):    at org.json.JSONTokener.nextValue(JSONTokener.java:94)
10-17 20:02:20.745: E/AndroidRuntime(17009):    at org.json.JSONObject.<init>(JSONObject.java:154)
10-17 20:02:20.745: E/AndroidRuntime(17009):    at org.json.JSONObject.<init>(JSONObject.java:171)
10-17 20:02:20.745: E/AndroidRuntime(17009):    at com.example.checkweather.MainActivity.onCreate(MainActivity.java:94)
10-17 20:02:20.745: E/AndroidRuntime(17009):    at android.app.Activity.performCreate(Activity.java:5179)
10-17 20:02:20.745: E/AndroidRuntime(17009):    at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1094)
10-17 20:02:20.745: E/AndroidRuntime(17009):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2074)
10-17 20:02:20.745: E/AndroidRuntime(17009):    ... 11 more

score 1 · Accepted Answer

在这些行中，您使用索引 3 从数组中获取值，但数组只有 3 个元素，因此索引可以是 0 到 2：

JSONObject jObj9 = new JSONObject(high[3]);
JSONObject jObj10 = new JSONObject(low[3]);

score 0 · Accepted Answer

您的错误是ArrayIndexOutOfBoundsException 这意味着您正在尝试从数组中获取一些甚至不存在的东西，即如果数组的长度为 5，那么您正在尝试从数组中获取第 6 个元素。检查您的结果，然后考虑到数组的大小，使用循环相应地解析 json。

score 0 · Accepted Answer

0

在 108 行中，只需在 for 循环的条件部分将值减 1。

于 2013-10-17T04:36:10.033 回答

android - Android：FATAL EXCEPTION MAIN .. 应用程序每次都崩溃

3 回答 3

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