Question

当我点击我的应用程序上的发送按钮时，应用程序崩溃：

06-30 13:57:46.487: E/AndroidRuntime(12201): FATAL EXCEPTION: main
    06-30 13:57:46.487: E/AndroidRuntime(12201): java.lang.IllegalStateException:
 Could not find a method send(View) in the activity class com.yoursite.helloworld.MainActivity 
for onClick handler on view class android.widget.Button with id 'sendButton'

我的MainActivity.java：

        package com.yoursite.helloworld;

    import android.os.Bundle;
    import android.app.Activity;
    import android.view.Menu;

    public class MainActivity extends Activity {

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


        @Override
        public boolean onCreateOptionsMenu(Menu menu) {
            // Inflate the menu; this adds items to the action bar if it is present.
            getMenuInflater().inflate(R.menu.main, menu);
            return true;
        }

    }

my HelloWorldActivity.java:
package com.yoursite.helloworld;

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

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.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

public class HelloWorldActivity extends Activity {
    Button sendButton;

    EditText msgTextField;

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        // load the layout
        setContentView(R.layout.activity_main);        

        // make message text field object
        msgTextField = (EditText) findViewById(R.id.msgTextField);
        // make send button object
        sendButton = (Button) findViewById(R.id.sendButton);

    }

    // this is the function that gets called when you click the button
    public void send(View v)
    {
        // get the message from the message text box
        String msg = msgTextField.getText().toString();  

        // make sure the fields are not empty
        if (msg.length()>0)
        {
            HttpClient httpclient = new DefaultHttpClient();
            HttpPost httppost = new HttpPost("http://mysite.com/test.php");
         try {
           List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>(2);
           nameValuePairs.add(new BasicNameValuePair("user", "12345"));
           nameValuePairs.add(new BasicNameValuePair("name", msg));
           httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
           httpclient.execute(httppost);
           msgTextField.setText(""); // clear text box
         } catch (ClientProtocolException e) {
             // TODO Auto-generated catch block
         } catch (IOException e) {
             // TODO Auto-generated catch block
         }

        }
        else
        {
            // display message if text fields are empty
            Toast.makeText(getBaseContext(),"All field are required",Toast.LENGTH_SHORT).show();
        }

    }
}

my activity_main.xml：

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

    <EditText
        android:id="@+id/msgTextField"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        />
    <Button
        android:text="Send"
        android:id="@+id/sendButton"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:onClick="send"
        /> 

</LinearLayout>

和AndroidManifest.xml：

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

    <uses-sdk
        android:minSdkVersion="8"
        android:targetSdkVersion="16" />
<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="com.yoursite.helloworld.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>

我正在尝试按照本教程http://webtutsdepot.com/2011/11/15/android-tutorial-how-to-post-data-from-an-android-app-to-a-website/尝试一切并没有成功，需要一些初学者的帮助！

Answer 1

您的send（）方法位于HelloWorldActivity，而您的布局在MainActivity中充气。

将您的send（）方法移至MainActivity，或在其他活动中为您的布局充气。

当我点击按钮时，我的应用程序崩溃了

1 个答案: