cómo solucionarlo: EXCEPCIÓN FATAL: main android.os.NetworkOnMainThreadException

android-asynctask database-connection

Question

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• ¿Cómo arreglo la excepción android.os.NetworkOnMainThreadException? 46 respuestas

Estoy teniendo probelmas ejecutando mi código en la versión de Android 18. He usado AsyncTask pero sigo recibiendo un error, por favor ayuda. Soy un novato en programación así que disculpe mis errores

package com.example.androidhive;

import java.util.ArrayList;

import java.util.List;

import org.apache.http.NameValuePair;
import org.apache.http.message.BasicNameValuePair;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import android.app.Activity;
import android.app.ProgressDialog;
import android.content.Intent;
import android.os.AsyncTask;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;


public class EditProductActivity extends Activity {



    EditText txtName;
    EditText txtPrice;
    EditText txtDesc;
    EditText txtCreatedAt;
    Button btnSave;
    Button btnDelete;

    String pid;


    // Progress Dialog
    private ProgressDialog pDialog;

    // JSON parser class
    JSONParser jsonParser = new JSONParser();

    // single product url
    private static final String url_product_detials = "http://10.0.2.2/android_connect/get_product_details.php";

    // url to update product
    private static final String url_update_product = "http://10.0.2.2/android_connect/update_product.php";

    // url to delete product
    private static final String url_delete_product = "http://10.0.2.2/android_connect/delete_product.php";

    // JSON Node names
    private static final String TAG_SUCCESS = "success";
    private static final String TAG_PRODUCT = "product";
    private static final String TAG_PID = "pid";
    private static final String TAG_NAME = "name";
    private static final String TAG_PRICE = "price";
    private static final String TAG_DESCRIPTION = "description";

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

        // save button
        btnSave = (Button) findViewById(R.id.btnSave);
        btnDelete = (Button) findViewById(R.id.btnDelete);


        // getting product details from intent
        Intent i = getIntent();

        // getting product id (pid) from intent
        pid = i.getStringExtra(TAG_PID);

        // Getting complete product details in background thread
        new GetProductDetails().execute();

        // save button click event
        btnSave.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View arg0) {
                // starting background task to update product
                new SaveProductDetails().execute();
            }
        });

        // Delete button click event
        btnDelete.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View arg0) {
                // deleting product in background thread
                new DeleteProduct().execute();
            }
        });

    }

    /**
     * Background Async Task to Get complete product details
     * */
    class GetProductDetails extends AsyncTask<String, String, String> {

        /**
         * Before starting background thread Show Progress Dialog
         * */
        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            pDialog = new ProgressDialog(EditProductActivity.this);
            pDialog.setMessage("Loading product details. Please wait...");
            pDialog.setIndeterminate(false);
            pDialog.setCancelable(true);
            pDialog.show();
        }

        /**
         * Getting product details in background thread
         * */
        protected String doInBackground(String... params) {

            // updating UI from Background Thread
            runOnUiThread(new Runnable() {
                public void run() {
                    // Check for success tag
                    int success;
                    try {
                        // Building Parameters
                        List<NameValuePair> params = new ArrayList<NameValuePair>();
                        params.add(new BasicNameValuePair("pid", pid));

                        // getting product details by making HTTP request
                        // Note that product details url will use GET request
                        JSONObject json = jsonParser.makeHttpRequest(
                                url_product_detials, "GET", params);

                        // check your log for json response
                        Log.d("Single Product Details", json.toString());

                        // json success tag
                        success = json.getInt(TAG_SUCCESS);
                        if (success == 1) {
                            // successfully received product details
                            JSONArray productObj = json
                                    .getJSONArray(TAG_PRODUCT); // JSON Array

                            // get first product object from JSON Array
                            JSONObject product = productObj.getJSONObject(0);
                            setContentView(R.layout.edit_product);

                            // product with this pid found
                            // Edit Text
                            txtName = (EditText) findViewById(R.id.inputName);
                            txtPrice = (EditText) findViewById(R.id.inputPrice);
                            txtDesc = (EditText) findViewById(R.id.inputDesc);

                            // display product data in EditText
                            txtName.setText(product.getString(TAG_NAME));
                            txtPrice.setText(product.getString(TAG_PRICE));
                            txtDesc.setText(product.getString(TAG_DESCRIPTION));

                        }else{
                            // product with pid not found
                        }
                    } catch (JSONException e) {
                        e.printStackTrace();
                    }
                }
            });

            return null;
        }


        /**
         * After completing background task Dismiss the progress dialog
         * **/
        protected void onPostExecute(String file_url) {
            // dismiss the dialog once got all details
            pDialog.dismiss();
        }
    }

    /**
     * Background Async Task to  Save product Details
     * */
    class SaveProductDetails extends AsyncTask<String, String, String> {

        /**
         * Before starting background thread Show Progress Dialog
         * */
        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            pDialog = new ProgressDialog(EditProductActivity.this);
            pDialog.setMessage("Saving product ...");
            pDialog.setIndeterminate(false);
            pDialog.setCancelable(true);
            pDialog.show();
        }

        /**
         * Saving product
         * */
        protected String doInBackground(String... args) {

            // getting updated data from EditTexts
            String name = txtName.getText().toString();
            String price = txtPrice.getText().toString();
            String description = txtDesc.getText().toString();

            // Building Parameters
            List<NameValuePair> params = new ArrayList<NameValuePair>();
            params.add(new BasicNameValuePair(TAG_PID, pid));
            params.add(new BasicNameValuePair(TAG_NAME, name));
            params.add(new BasicNameValuePair(TAG_PRICE, price));
            params.add(new BasicNameValuePair(TAG_DESCRIPTION, description));

            // sending modified data through http request
            // Notice that update product url accepts POST method
            JSONObject json = jsonParser.makeHttpRequest(url_update_product,
                    "POST", params);

            // check json success tag
            try {
                int success = json.getInt(TAG_SUCCESS);

                if (success == 1) {
                    // successfully updated
                    Intent i = getIntent();
                    // send result code 100 to notify about product update
                    setResult(100, i);
                    finish();
                } else {
                    // failed to update product
                }
            } catch (JSONException e) {
                e.printStackTrace();
            }

            return null;
        }


        /**
         * After completing background task Dismiss the progress dialog
         * **/
        protected void onPostExecute(String file_url) {
            // dismiss the dialog once product updated
            pDialog.dismiss();
        }
    }

    /*****************************************************************
     * Background Async Task to Delete Product
     * */
    class DeleteProduct extends AsyncTask<String, String, String> {

        /**
         * Before starting background thread Show Progress Dialog
         * */
        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            pDialog = new ProgressDialog(EditProductActivity.this);
            pDialog.setMessage("Deleting Product...");
            pDialog.setIndeterminate(false);
            pDialog.setCancelable(true);
            pDialog.show();
        }

        /**
         * Deleting product
         * */
        protected String doInBackground(String... args) {

            // Check for success tag
            int success;
            try {
                // Building Parameters
                List<NameValuePair> params = new ArrayList<NameValuePair>();
                params.add(new BasicNameValuePair("pid", pid));

                // getting product details by making HTTP request
                JSONObject json = jsonParser.makeHttpRequest(
                        url_delete_product, "POST", params);

                // check your log for json response
                Log.d("Delete Product", json.toString());

                // json success tag
                success = json.getInt(TAG_SUCCESS);
                if (success == 1) {
                    // product successfully deleted
                    // notify previous activity by sending code 100
                    Intent i = getIntent();
                    // send result code 100 to notify about product      deletion
                    setResult(100, i);
                    finish();
                }
            } catch (JSONException e) {
                e.printStackTrace();
            }

            return null;
        }

        /**
         * After completing background task Dismiss the progress dialog
         * **/
        protected void onPostExecute(String file_url) {
            // dismiss the dialog once product deleted
            pDialog.dismiss();

        }

    }
    }

el error que estoy recibiendo es:

10-27 17:01:52.858: E/AndroidRuntime(2001): FATAL EXCEPTION: main
10-27 17:01:52.858: E/AndroidRuntime(2001): android.os.NetworkOnMainThreadException
10-27 17:01:52.858: E/AndroidRuntime(2001):     at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1133)
10-27 17:01:52.858: E/AndroidRuntime(2001):     at libcore.io.BlockGuardOs.connect(BlockGuardOs.java:84)
10-27 17:01:52.858: E/AndroidRuntime(2001):     at libcore.io.IoBridge.connectErrno(IoBridge.java:127)
10-27 17:01:52.858: E/AndroidRuntime(2001):     at libcore.io.IoBridge.connect(IoBridge.java:112)
10-27 17:01:52.858: E/AndroidRuntime(2001):     at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:192)
10-27 17:01:52.858: E/AndroidRuntime(2001):     at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:459)
10-27 17:01:52.858: E/AndroidRuntime(2001):     at java.net.Socket.connect(Socket.java:842)
10-27 17:01:52.858: E/AndroidRuntime(2001):     at org.apache.http.conn.scheme.PlainSocketFactory.connectSocket(PlainSocketFactory.java:119)
10-27 17:01:52.858: E/AndroidRuntime(2001):     at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:144)
10-27 17:01:52.858: E/AndroidRuntime(2001):     at org.apache.http.impl.conn.AbstractPoolEntry.open(AbstractPoolEntry.java:164)
10-27 17:01:52.858: E/AndroidRuntime(2001):     at org.apache.http.impl.conn.AbstractPooledConnAdapter.open(AbstractPooledConnAdapter.java:119)
10-27 17:01:52.858: E/AndroidRuntime(2001):     at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:360)
10-27 17:01:52.858: E/AndroidRuntime(2001):     at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:555)
10-27 17:01:52.858: E/AndroidRuntime(2001):     at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:487)
10-27 17:01:52.858: E/AndroidRuntime(2001):     at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:465)
10-27 17:01:52.858: E/AndroidRuntime(2001):     at com.example.androidhive.JSONParser.makeHttpRequest(JSONParser.java:62)
10-27 17:01:52.858: E/AndroidRuntime(2001):     at com.example.androidhive.EditProductActivity$GetProductDetails$1.run(EditProductActivity.java:137)
10-27 17:01:52.858: E/AndroidRuntime(2001):     at android.os.Handler.handleCallback(Handler.java:730)
10-27 17:01:52.858: E/AndroidRuntime(2001):     at android.os.Handler.dispatchMessage(Handler.java:92)
10-27 17:01:52.858: E/AndroidRuntime(2001):     at android.os.Looper.loop(Looper.java:137)
10-27 17:01:52.858: E/AndroidRuntime(2001):     at android.app.ActivityThread.main(ActivityThread.java:5103)
10-27 17:01:52.858: E/AndroidRuntime(2001):     at java.lang.reflect.Method.invokeNative(Native Method)
10-27 17:01:52.858: E/AndroidRuntime(2001):     at java.lang.reflect.Method.invoke(Method.java:525)
10-27 17:01:52.858: E/AndroidRuntime(2001):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:737)
10-27 17:01:52.858: E/AndroidRuntime(2001):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
10-27 17:01:52.858: E/AndroidRuntime(2001):     at dalvik.system.NativeStart.main(Native Method)

y el diseño xml de diseño se ve así:

<?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" >

    <!-- Name Label -->

    <TextView
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:paddingLeft="10dip"
        android:paddingRight="10dip"
        android:paddingTop="10dip"
        android:text="@string/Product_Name2"
        android:textSize="17sp" />

    <!-- Input Name -->
    <EditText android:id="@+id/inputName"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:hint="@string/inputName2"
        android:layout_margin="5dip"
        android:layout_marginBottom="15dip"
        android:singleLine="true"/>

    <!-- Price Label -->

    <TextView
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:paddingLeft="10dip"
        android:paddingRight="10dip"
        android:paddingTop="10dip"
        android:text="@string/Price2"
        android:textSize="17sp" />

    <!-- Input Price -->
    <EditText android:id="@+id/inputPrice"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_margin="5dip"
        android:layout_marginBottom="15dip"
        android:singleLine="true"
        android:inputType="numberDecimal"/>

    <!-- Description Label -->

    <TextView
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:paddingLeft="10dip"
        android:paddingRight="10dip"
        android:paddingTop="10dip"
        android:text="@string/Description2"
        android:textSize="17sp" />

    <!-- Input description -->
    <EditText android:id="@+id/inputDesc"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:hint="@string/inputDesc2"
        android:layout_margin="5dip"
        android:layout_marginBottom="15dip"
        android:lines="4"
        android:gravity="top"/>

    <LinearLayout android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal">
        <!-- Button Create Product -->

    <Button
        android:id="@+id/btnSave"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_weight="1"
        android:text="@string/Save_Changes" />

    <!-- Button Create Product -->

    <Button
        android:id="@+id/btnDelete"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_weight="1"
        android:text="@string/Delete" />

    </LinearLayout>

</LinearLayout>

Answer 1

En la clase GetProductDetails use solo try catch. eliminar el runOnUiThread ().

Answer 2

En el método doInBackground debe mantener la solicitud HTTP en la tarea de fondo y simplemente colocar la actualización de la UI en runOnUiThread . Aquí está la solución ''rápida'':

/**
 * Getting product details in background thread
 * */
protected String doInBackground(String... params) {

    // Check for success tag
    int success;
    try {
        // Building Parameters
        List<NameValuePair> params = new ArrayList<NameValuePair>();
        params.add(new BasicNameValuePair("pid", pid));

        // getting product details by making HTTP request
        // Note that product details url will use GET request
        JSONObject json = jsonParser.makeHttpRequest(
                url_product_detials, "GET", params);

        // check your log for json response
        Log.d("Single Product Details", json.toString());

        // json success tag
        success = json.getInt(TAG_SUCCESS);
        if (success == 1) {
            // successfully received product details
            JSONArray productObj = json
                    .getJSONArray(TAG_PRODUCT); // JSON Array

            // get first product object from JSON Array
            final JSONObject product = productObj.getJSONObject(0);

            // updating UI from Background Thread
            runOnUiThread(new Runnable() {
                public void run() {
                    setContentView(R.layout.edit_product);

                    // product with this pid found
                    // Edit Text
                    txtName = (EditText) findViewById(R.id.inputName);
                    txtPrice = (EditText) findViewById(R.id.inputPrice);
                    txtDesc = (EditText) findViewById(R.id.inputDesc);

                    // display product data in EditText
                    txtName.setText(product.getString(TAG_NAME));
                    txtPrice.setText(product.getString(TAG_PRICE));
                    txtDesc.setText(product.getString(TAG_DESCRIPTION));
                }
            });

        }else{
            // product with pid not found
        }
    } catch (JSONException e) {
        e.printStackTrace();
    }

    return null;
}

La solución recomendada es cambiar el método doInBackground para devolver el resultado de la solicitud y actualizar la IU en onPostExecute siguiente manera:

/**
 * Background Async Task to Get complete product details
 * */
class GetProductDetails extends AsyncTask<String, String, JSONObject> {

    /**
     * Before starting background thread Show Progress Dialog
     * */
    @Override
    protected void onPreExecute() {
        super.onPreExecute();
        pDialog = new ProgressDialog(EditProductActivity.this);
        pDialog.setMessage("Loading product details. Please wait...");
        pDialog.setIndeterminate(false);
        pDialog.setCancelable(true);
        pDialog.show();
    }

    /**
     * Getting product details in background thread
     * */
    protected JSONObject doInBackground(String... params) {

        JSONObject product = null;
        // Check for success tag
        int success;
        try {
            // Building Parameters
            List<NameValuePair> params = new ArrayList<NameValuePair>();
            params.add(new BasicNameValuePair("pid", pid));

            // getting product details by making HTTP request
            // Note that product details url will use GET request
            JSONObject json = jsonParser.makeHttpRequest(
                    url_product_detials, "GET", params);

            // check your log for json response
            Log.d("Single Product Details", json.toString());

            // json success tag
            success = json.getInt(TAG_SUCCESS);
            if (success == 1) {
                // successfully received product details
                JSONArray productObj = json
                        .getJSONArray(TAG_PRODUCT); // JSON Array

                // get first product object from JSON Array
                product = productObj.getJSONObject(0);
            }else{
                // product with pid not found
            }
        } catch (JSONException e) {
            e.printStackTrace();
        }

        return product;
    }

    /**
     * After completing background task Dismiss the progress dialog
     * **/
    protected void onPostExecute(JSONObject product) {
        if (product != null) {
            setContentView(R.layout.edit_product);

            // product with this pid found
            // Edit Text
            txtName = (EditText) findViewById(R.id.inputName);
            txtPrice = (EditText) findViewById(R.id.inputPrice);
            txtDesc = (EditText) findViewById(R.id.inputDesc);

            // display product data in EditText
            txtName.setText(product.getString(TAG_NAME));
            txtPrice.setText(product.getString(TAG_PRICE));
            txtDesc.setText(product.getString(TAG_DESCRIPTION));

        }
        // dismiss the dialog once got all details
        pDialog.dismiss();
    }
}