Question

我一直在关注YouTube视频，该视频解释了如何将数据从Android应用程序插入到mySQL中。它对我不起作用，我也不知道自己做错了什么。它只是在我执行它时就会中断。甚至没有加载textViews和Buttons

这是我的MainActivity：

package com.example.insertbbdd;

import java.io.IOException;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.List;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.message.BasicNameValuePair;



import android.app.Activity;
import android.os.Bundle;
import android.os.StrictMode;
import android.support.v4.app.Fragment;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

public class MainActivity extends Activity {

    EditText eName, eAge, eMail;
    Button bSumbit;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main_activity);

        StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
        StrictMode.setThreadPolicy(policy);

        eName = (EditText) findViewById(R.id.editName);
        eAge = (EditText) findViewById(R.id.editAge);
        eMail = (EditText) findViewById(R.id.editMail);
        bSumbit = (Button) findViewById(R.id.submitButton);

        bSumbit.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                InputStream is = null;

                String name = "" + eName.getText().toString();
                String age = "" + eAge.getText().toString();
                String email = "" + eMail.getText().toString();

                List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>(1);

                nameValuePairs.add(new BasicNameValuePair("name", name));
                nameValuePairs.add(new BasicNameValuePair("age", age));
                nameValuePairs.add(new BasicNameValuePair("email", email));


                try{
                    HttpClient httpClient = new DefaultHttpClient();

                    HttpPost httpPost = new HttpPost("http://accessibility.es/prueba/script.php");

                    httpPost.setEntity(new UrlEncodedFormEntity(nameValuePairs));

                    HttpResponse response = httpClient.execute(httpPost);

                    HttpEntity entity = response.getEntity();

                    is = entity.getContent();

                    String msg = "Data entered succesfully";
                    Toast.makeText(getApplicationContext(), msg, Toast.LENGTH_LONG).show();

                }
                catch(ClientProtocolException e){
                    Log.e("Client Protocol", "Log_tag");
                    e.printStackTrace();
                }
                catch(IOException e){
                    Log.e("Log tag", "IOException");
                    e.printStackTrace();
                }

            }
        });


    }


}

这是我的main_activity.xml：

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/RelativeLayout1"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >

    <Button
        android:id="@+id/submitButton"
        style="?android:attr/buttonStyleSmall"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignLeft="@+id/editName"
        android:layout_alignParentBottom="true"
        android:layout_marginBottom="130dp"
        android:text="Button" />

    <TextView
        android:id="@+id/editMail"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_above="@+id/submitButton"
        android:layout_alignRight="@+id/editName"
        android:layout_marginBottom="54dp"
        android:layout_marginRight="17dp"
        android:text="Large Text"
        android:textAppearance="?android:attr/textAppearanceLarge" />

    <TextView
        android:id="@+id/editAge"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_above="@+id/editMail"
        android:layout_alignLeft="@+id/editMail"
        android:layout_marginBottom="43dp"
        android:text="Large Text"
        android:textAppearance="?android:attr/textAppearanceLarge" />

    <TextView
        android:id="@+id/editName"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_above="@+id/editAge"
        android:layout_alignParentLeft="true"
        android:layout_marginBottom="35dp"
        android:layout_marginLeft="90dp"
        android:text="Large Text"
        android:textAppearance="?android:attr/textAppearanceLarge" />

</RelativeLayout>

这是我的AndroidManifest：

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.insertbbdd"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="14"
        android:targetSdkVersion="21" />
    <uses-permission android:name="android.permission.INTERNET"/>

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name=".MainActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

Answer 1

我猜你得到的是ClassCastException，因为你试图在(EditText)上拨打TextView。

改变这个：

TextView eName, eAge, eMail;

eName = (TextView) findViewById(R.id.editName);
eAge = (TextView) findViewById(R.id.editAge);
eMail = (TextView) findViewById(R.id.editMail);
bSumbit = (Button) findViewById(R.id.submitButton);

或将xml标记从TextView更改为EditText。

<EditText />

NB：其他人指出的内容也是正确的。如果您点击提交按钮，您将获得

android.os.NetworkOnMainThreadException

因此您需要使用Handler或AsyncTask

Answer 2

您需要在与主UI线程分开的线程中执行任何网络操作，例如HttpPost（或者实际上任何其他慢速操作），然后使用回调来更新主线程上的UI。

有关主要文档，请参阅http://developer.android.com/guide/components/processes-and-threads.html和http://developer.android.com/reference/android/os/AsyncTask.html。网上还有许多指南，例如http://www.vogella.com/tutorials/AndroidBackgroundProcessing/article.html

Answer 3

试试这个..

try{
                new Thread(new Runnable() {
            public void run() {

               HttpClient httpClient = new DefaultHttpClient();

                HttpPost httpPost = new HttpPost("http://accessibility.es/prueba/script.php");

                httpPost.setEntity(new UrlEncodedFormEntity(nameValuePairs));

                HttpResponse response = httpClient.execute(httpPost);

                HttpEntity entity = response.getEntity();

                is = entity.getContent();

                String msg = "Data entered succesfully";
                Toast.makeText(getApplicationContext(), msg, Toast.LENGTH_LONG).show();

            }
            catch(ClientProtocolException e){
                Log.e("Client Protocol", "Log_tag");
                e.printStackTrace();
            }
            catch(IOException e){
                Log.e("Log tag", "IOException");
                e.printStackTrace();
            }

                }
        }).start();

将Android应用程序中的数据插入mySql数据库

3 个答案: