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我尝试在姜饼中应用本教程,它运行良好 http://www.androidhive.info/2012/01/android-json-parsing-tutorial/ 但它在 ICS 上崩溃(在三星 S2 和 HTC one X real设备不是模拟器)。

那么如何为广泛的电话编写公共应用程序..?今天遇到这个问题后我真的很沮丧。即使我在你的帮助下解决了这个问题。是否有官方说明页面或类似的东西知道如何更新姜饼代码以使其与 ICS 兼容。?最好的祝福 。

package com.example.json.pwd;

import java.util.ArrayList;
import java.util.HashMap;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import android.app.ListActivity;
import android.content.Intent;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.SimpleAdapter;
import android.widget.TextView;

public class AndroidJSONParsingActivity extends ListActivity {

    // url to make request
    private static String url = "http://api.androidhive.info/contacts/";

    // JSON Node names
    private static final String TAG_CONTACTS = "contacts";
    private static final String TAG_ID = "id";
    private static final String TAG_NAME = "name";
    private static final String TAG_EMAIL = "email";
    private static final String TAG_ADDRESS = "address";
    private static final String TAG_GENDER = "gender";
    private static final String TAG_PHONE = "phone";
    private static final String TAG_PHONE_MOBILE = "mobile";
    private static final String TAG_PHONE_HOME = "home";
    private static final String TAG_PHONE_OFFICE = "office";

    // contacts JSONArray
    JSONArray contacts = null;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        // Hashmap for ListView
        ArrayList<HashMap<String, String>> contactList = new ArrayList<HashMap<String, String>>();

        // Creating JSON Parser instance
        JSONParser jParser = new JSONParser();

        // getting JSON string from URL
        JSONObject json = jParser.getJSONFromUrl(url);

        try {
            // Getting Array of Contacts
            contacts = json.getJSONArray(TAG_CONTACTS);

            // looping through All Contacts
            for(int i = 0; i < contacts.length(); i++){
                JSONObject c = contacts.getJSONObject(i);

                // Storing each json item in variable
                String id = c.getString(TAG_ID);
                String name = c.getString(TAG_NAME);
                String email = c.getString(TAG_EMAIL);
                String address = c.getString(TAG_ADDRESS);
                String gender = c.getString(TAG_GENDER);

                // Phone number is agin JSON Object
                JSONObject phone = c.getJSONObject(TAG_PHONE);
                String mobile = phone.getString(TAG_PHONE_MOBILE);
                String home = phone.getString(TAG_PHONE_HOME);
                String office = phone.getString(TAG_PHONE_OFFICE);

                // creating new HashMap
                HashMap<String, String> map = new HashMap<String, String>();

                // adding each child node to HashMap key => value
                map.put(TAG_ID, id);
                map.put(TAG_NAME, name);
                map.put(TAG_EMAIL, email);
                map.put(TAG_PHONE_MOBILE, mobile);

                // adding HashList to ArrayList
                contactList.add(map);
            }
        } catch (JSONException e) {
            e.printStackTrace();
        }


        /**
         * Updating parsed JSON data into ListView
         * */
        ListAdapter adapter = new SimpleAdapter(this, contactList,
                R.layout.list_item,
                new String[] { TAG_NAME, TAG_EMAIL, TAG_PHONE_MOBILE }, new int[] {
                        R.id.name, R.id.email, R.id.mobile });

        setListAdapter(adapter);

        // selecting single ListView item
        ListView lv = getListView();

        // Launching new screen on Selecting Single ListItem
        lv.setOnItemClickListener(new OnItemClickListener() {

            @Override
            public void onItemClick(AdapterView<?> parent, View view,
                    int position, long id) {
                // getting values from selected ListItem
                String name = ((TextView) view.findViewById(R.id.name)).getText().toString();
                String cost = ((TextView) view.findViewById(R.id.email)).getText().toString();
                String description = ((TextView) view.findViewById(R.id.mobile)).getText().toString();

                // Starting new intent
                Intent in = new Intent(getApplicationContext(), SingleMenuItemActivity.class);
                in.putExtra(TAG_NAME, name);
                in.putExtra(TAG_EMAIL, cost);
                in.putExtra(TAG_PHONE_MOBILE, description);
                startActivity(in);

            }
        });
    }
}

package com.example.json.pwd;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.UnsupportedEncodingException;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.json.JSONException;
import org.json.JSONObject;

import android.util.Log;

public class JSONParser {

    static InputStream is = null;
    static JSONObject jObj = null;
    static String json = "";

    // constructor
    public JSONParser() {

    }

    public JSONObject getJSONFromUrl(String url) {

        // Making HTTP request
        try {
            // defaultHttpClient
            DefaultHttpClient httpClient = new DefaultHttpClient();
            HttpPost httpPost = new HttpPost(url);

            HttpResponse httpResponse = httpClient.execute(httpPost);
            HttpEntity httpEntity = httpResponse.getEntity();
            is = httpEntity.getContent();           

        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        } catch (ClientProtocolException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

        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();
            json = sb.toString();
        } catch (Exception e) {
            Log.e("Buffer Error", "Error converting result " + e.toString());
        }

        // try parse the string to a JSON object
        try {
            jObj = new JSONObject(json);
        } catch (JSONException e) {
            Log.e("JSON Parser", "Error parsing data " + e.toString());
        }

        // return JSON String
        return jObj;

    }
}

package com.example.json.pwd;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.widget.TextView;

public class SingleMenuItemActivity  extends Activity {

    // JSON node keys
    private static final String TAG_NAME = "name";
    private static final String TAG_EMAIL = "email";
    private static final String TAG_PHONE_MOBILE = "mobile";
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.single_list_item);

        // getting intent data
        Intent in = getIntent();

        // Get JSON values from previous intent
        String name = in.getStringExtra(TAG_NAME);
        String cost = in.getStringExtra(TAG_EMAIL);
        String description = in.getStringExtra(TAG_PHONE_MOBILE);

        // Displaying all values on the screen
        TextView lblName = (TextView) findViewById(R.id.name_label);
        TextView lblCost = (TextView) findViewById(R.id.email_label);
        TextView lblDesc = (TextView) findViewById(R.id.mobile_label);

        lblName.setText(name);
        lblCost.setText(cost);
        lblDesc.setText(description);
    }
}

Finally Logcat
09-25 21:56:13.262: D/AndroidRuntime(1475): Shutting down VM
09-25 21:56:13.262: W/dalvikvm(1475): threadid=1: thread exiting with uncaught exception (group=0xb40a0180)
09-25 21:56:13.343: E/AndroidRuntime(1475): FATAL EXCEPTION: main
09-25 21:56:13.343: E/AndroidRuntime(1475): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.json.pwd/com.example.json.pwd.AndroidJSONParsingActivity}: android.os.NetworkOnMainThreadException
09-25 21:56:13.343: E/AndroidRuntime(1475):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1956)
09-25 21:56:13.343: E/AndroidRuntime(1475):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1981)
09-25 21:56:13.343: E/AndroidRuntime(1475):     at android.app.ActivityThread.access$600(ActivityThread.java:123)
09-25 21:56:13.343: E/AndroidRuntime(1475):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1147)
09-25 21:56:13.343: E/AndroidRuntime(1475):     at android.os.Handler.dispatchMessage(Handler.java:99)
09-25 21:56:13.343: E/AndroidRuntime(1475):     at android.os.Looper.loop(Looper.java:137)
09-25 21:56:13.343: E/AndroidRuntime(1475):     at android.app.ActivityThread.main(ActivityThread.java:4424)
09-25 21:56:13.343: E/AndroidRuntime(1475):     at java.lang.reflect.Method.invokeNative(Native Method)
09-25 21:56:13.343: E/AndroidRuntime(1475):     at java.lang.reflect.Method.invoke(Method.java:511)
09-25 21:56:13.343: E/AndroidRuntime(1475):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
09-25 21:56:13.343: E/AndroidRuntime(1475):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
09-25 21:56:13.343: E/AndroidRuntime(1475):     at dalvik.system.NativeStart.main(Native Method)
09-25 21:56:13.343: E/AndroidRuntime(1475): Caused by: android.os.NetworkOnMainThreadException
09-25 21:56:13.343: E/AndroidRuntime(1475):     at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1099)
09-25 21:56:13.343: E/AndroidRuntime(1475):     at java.net.InetAddress.lookupHostByName(InetAddress.java:391)
09-25 21:56:13.343: E/AndroidRuntime(1475):     at java.net.InetAddress.getAllByNameImpl(InetAddress.java:242)
09-25 21:56:13.343: E/AndroidRuntime(1475):     at java.net.InetAddress.getAllByName(InetAddress.java:220)
09-25 21:56:13.343: E/AndroidRuntime(1475):     at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:137)
09-25 21:56:13.343: E/AndroidRuntime(1475):     at org.apache.http.impl.conn.AbstractPoolEntry.open(AbstractPoolEntry.java:164)
09-25 21:56:13.343: E/AndroidRuntime(1475):     at org.apache.http.impl.conn.AbstractPooledConnAdapter.open(AbstractPooledConnAdapter.java:119)
09-25 21:56:13.343: E/AndroidRuntime(1475):     at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:360)
09-25 21:56:13.343: E/AndroidRuntime(1475):     at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:555)
09-25 21:56:13.343: E/AndroidRuntime(1475):     at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:487)
09-25 21:56:13.343: E/AndroidRuntime(1475):     at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:465)
09-25 21:56:13.343: E/AndroidRuntime(1475):     at com.example.json.pwd.JSONParser.getJSONFromUrl(JSONParser.java:38)
09-25 21:56:13.343: E/AndroidRuntime(1475):     at com.example.json.pwd.AndroidJSONParsingActivity.onCreate(AndroidJSONParsingActivity.java:54)
09-25 21:56:13.343: E/AndroidRuntime(1475):     at android.app.Activity.performCreate(Activity.java:4465)
09-25 21:56:13.343: E/AndroidRuntime(1475):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1049)
09-25 21:56:13.343: E/AndroidRuntime(1475):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1920)
09-25 21:56:13.343: E/AndroidRuntime(1475):     ... 11 more
09-25 21:56:21.553: I/dalvikvm(1475): threadid=3: reacting to signal 3
09-25 21:56:21.563: I/dalvikvm(1475): Wrote stack traces to '/data/anr/traces.txt'
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1 回答 1

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应该是由于Android 3.0以后实现了Strict模式,任何时候像网络调用这样的实现,数据库实现都需要在Asynctask或者线程里面调用。

于 2012-09-25T18:56:37.243 回答