Java 当我点击按钮时,我的应用程序正在崩溃
当我单击应用程序上的“发送”按钮时,应用程序会崩溃,原因是:Java 当我点击按钮时,我的应用程序正在崩溃,java,android,Java,Android,当我单击应用程序上的“发送”按钮时,应用程序会崩溃,原因是: 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
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'
my 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();
}
}
}
package com.yoursite.helloworld;
导入android.os.Bundle;
导入android.app.Activity;
导入android.view.Menu;
公共类MainActivity扩展了活动{
@凌驾
创建时受保护的void(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
@凌驾
公共布尔onCreateOptions菜单(菜单){
//为菜单充气;这会将项目添加到操作栏(如果存在)。
getMenuInflater().充气(R.menu.main,menu);
返回true;
}
}
my HelloWorldActivity.java:
包com.yoursite.helloworld;
导入java.io.IOException;
导入java.util.ArrayList;
导入java.util.List;
导入org.apache.http.NameValuePair;
导入org.apache.http.client.ClientProtocolException;
导入org.apache.http.client.HttpClient;
导入org.apache.http.client.entity.UrlEncodedFormEntity;
导入org.apache.http.client.methods.HttpPost;
导入org.apache.http.impl.client.DefaultHttpClient;
导入org.apache.http.message.BasicNameValuePair;
导入android.app.Activity;
导入android.os.Bundle;
导入android.view.view;
导入android.widget.Button;
导入android.widget.EditText;
导入android.widget.Toast;
公共类HelloWorldActivity扩展了活动{
按钮发送按钮;
编辑文本msgTextField;
/**在首次创建活动时调用*/
@凌驾
创建时的公共void(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
//加载布局
setContentView(R.layout.activity_main);
//使消息文本字段成为对象
msgTextField=(EditText)findViewById(R.id.msgTextField);
//生成发送按钮对象
sendButton=(按钮)findViewById(R.id.sendButton);
}
//这是单击按钮时调用的函数
公共无效发送(视图五)
{
//从消息文本框中获取消息
字符串msg=msgTextField.getText().toString();
//确保字段不是空的
如果(msg.length()>0)
{
HttpClient HttpClient=新的DefaultHttpClient();
HttpPost HttpPost=新的HttpPost(“http://mysite.com/test.php");
试一试{
List nameValuePairs=新的ArrayList(2);
添加(新的BasicNameValuePair(“用户”、“12345”);
添加(新的BasicNameValuePair(“name”,msg));
setEntity(新的UrlEncodedFormEntity(nameValuePairs));
httpclient.execute(httppost);
msgTextField.setText(“”;//清除文本框
}捕获(客户端协议例外e){
//TODO自动生成的捕捉块
}捕获(IOE异常){
//TODO自动生成的捕捉块
}
}
其他的
{
//如果文本字段为空,则显示消息
Toast.makeText(getBaseContext(),“所有字段都是必需的”,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>
并且尝试了所有的方法都没有成功,需要一些初学者的帮助吗 send()方法在HelloWorldActivity
中,而布局在MainActivity
中膨胀
将send()方法移动到MainActivity
,或者在其他活动中扩大布局。很公平,请发表评论removed@Raghav好的,我将send()移到了主活动中,但当我输入消息并按下按钮时,我得到java.lang.IllegalStateException:无法执行活动的方法