当我运行此应用程序时，致命异常显示错误无法启动活动组件

时间：2015-12-24 05:38:01

标签： java android sqlite

我正在尝试在列表视图应用中简单显示App::uses('AppController', 'Controller'); class UsersController extends AppController { public $paginate = array( 'limit' => 4, 'order' => 'User.id DESC' ); public function admin_userAdd() { if ($this->request->is('post')) { pr($this->request->data); $this->User->create(); if ($this->User->save($this->request->data)) { $this->Session->setFlash('The user has been saved'); return $this->redirect(array('action' => 'userList')); } $this->Session->setFlash('The user could not be saved. Please, try again.', 'error'); } } public function admin_userList(){ $users = $this->User->find('all'); $this->set('users', $this->paginate()); } public function admin_userEdit($id = null) { $this->User->id = $id; if (!$this->User->exists()) { throw new NotFoundException(__('Invalid user')); } if ($this->request->is('post') || $this->request->is('put')) { if ($this->User->save($this->request->data)) { //pr($this->request->data); die(); $this->Session->setFlash(__('The user has been saved')); return $this->redirect(array('action' => 'userList')); } $this->Session->setFlash( __('The user could not be saved. Please, try again.') ); } else { $this->request->data = $this->User->read(null, $id); unset($this->request->data['User']['password']); } } public function admin_passChange($id = null) { $this->User->id = $id; if (!empty($this->request->data)) { $password = $this->request->data['User']['pass1']; if ($this->User->saveField('password',$password)) { $this->Session->setFlash('Password has been changed.'); //return $this->redirect(array('action' => 'userEdit')); } else { $this->Session->setFlash('Password could not be changed.'); } } else { $this->request->data = $this->User->read(null, $id); } } } 中的所有记录。编译器没有检测到任何错误，但是当我运行应用程序时，它会收到运行时错误。

main_Activity.java 

App::uses('AuthComponent', 'Controller/Component');

class User extends AppModel {

    public $validate = array(
        'username' => array(
            'nonEmpty' => array(
                'rule' => array('notEmpty'),
                'message' => 'A username is required',
                'allowEmpty' => false
            ),
            'between' => array(
                'rule' => array('between', 4, 15),
                'required' => true,
                'message' => 'Usernames must be between 5 to 15 characters'
            ),
            'unique' => array(
                'on'         => 'create',
                'rule'    => array('isUniqueUsername'),
                'message' => 'This username is already in use'
            ),
            'alphaNumericDashUnderscore' => array(
                'rule'    => array('alphaNumericDashUnderscore'),
                'message' => 'Username can only be letters, numbers and underscores'
            ),
        ),
        'email' => array(
            'required' => array(
                'on' => 'create',
                'rule' => array('email', true),
                'message' => 'Please provide a valid email address.'
            ),
            'unique' => array(
                'on'      => 'create',
                'rule'    => array('isUniqueEmail'),
                'message' => 'This email is already in use',
            ),
            'between' => array(
                'rule' => array('between', 6, 60),
                'message' => 'Usernames must be between 6 to 60 characters'
            )
        ),
        'role' => array(
            'valid' => array(
                'rule' => array('inList', array('admin', 'editor', 'accountent')),
                'message' => 'Please enter a valid role',
                'allowEmpty' => false
            )
        ),
        'password' => array(
            'length' => array(
                'rule'      => array('between', 5, 40),
                'message'   => 'Your password must be between 5 and 40 characters.',
            ),
            'required' => array(
                'rule' => 'notEmpty',
                'message' => 'Please enter a password.'
            )
        ),
        'pass1' => array(
            'length' => array(
                'rule'      => array('between', 8, 40),
                'message'   => 'Your password must be between 5 and 40 characters.',
            ),
            'required' => array(
                'rule' => 'notEmpty',
                'message' => 'Please enter a password.'
            )
        )
    );
    public function beforeSave($options = array()) {
        // hash our password
        if (isset($this->data[$this->alias]['password'])) {
            $this->data[$this->alias]['password'] = AuthComponent::password($this->data[$this->alias]['password']);
        }

        // if we get a new password, hash it
        if (isset($this->data[$this->alias]['pass1'])) {
            $this->data[$this->alias]['pass1'] = AuthComponent::password($this->data[$this->alias]['pass1']);
        }
        return true;
        // fallback to our parent
        return parent::beforeSave($options);
    }

}

Show_Record.java（这是显示listview中所有用户详细信息的主类）

<?php echo $this->Session->flash(); ?>
<div class="row" style="float:right">
    Hi <?php echo $this->data['User']['username']; ?>
</div>
<div class="row">
    <div class="col-lg-6">
        <?php echo $this->Form->create('User'); ?>
        <?php

        echo $this->Form->input('pass1', array('label' =>'New Password', 'class' => 'form-control'));
        echo $this->Form->input('pass2', array('label' =>'Confirm Password', 'class' => 'form-control'));

        ?>

        <?php echo $this->Form->end(__('Submit', array('class' => 'btn btn-default'))); ?>
    </div>

show_recordAdapter.java

这是自定义适配器类

SQLite database

Databaseclass（其中定义了表的所有文件结构以及定义的方法）

package com.example.login_userauthentication;

import android.os.Bundle;
import android.app.Activity;
import android.content.Intent;
import android.view.Menu;
import android.view.View;

public class MainActivity extends Activity {

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

    public void Register(View v)
    {
        startActivity(new Intent(getApplicationContext(),Reg.class));
    }
    public void Login(View v)
    {
        startActivity(new Intent(getApplicationContext(),Login.class));
    }

    public void Show_allrecord(View v)
    {
        startActivity(new Intent(getApplicationContext(),Show_record.class));
    }
    public void update_record(View v)
    {
        startActivity(new Intent(getApplicationContext(),Update.class));
    }

    @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;
    }
}

Database_helper.java（其中定义了create table和create database）

package com.example.login_userauthentication;

import java.util.ArrayList;
import java.util.List;

import android.app.Activity;
import android.content.Context;
import android.os.Bundle;
import android.widget.ListView;

public class Show_record extends Activity
{
    Show_recordAdapter showrecord_adapter;
    ListView listview;
    ArrayList<Student> studentlist;
    Database helper=new Database();

    protected void onCreate(Bundle savedInstanceState)
    {
        System.out.println("show sumit");
        super.onCreate(savedInstanceState);
        setContentView(R.layout.show_recordlist);
        System.out.println("show_record activity");
        System.out.println("show sumit");
        helper=new Database();
        listview = (ListView) findViewById(R.id.listView1);
        studentlist=new ArrayList<Student>();
        studentlist = helper.getAllrecord();
        System.out.println(studentlist);
        System.out.println("show sumit");
        showrecord_adapter=new Show_recordAdapter(getApplicationContext(),studentlist);
        listview.setAdapter(showrecord_adapter);

//      listview.setAdapter(new Show_recordAdapter(this, studentlist,
//              getLayoutInflater()));
    }
}


package com.example.login_userauthentication;

import java.util.ArrayList;
import java.util.List;
import java.util.zip.Inflater;

这是logcat 

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.TextView;

public class Show_recordAdapter extends BaseAdapter 
{
    Context context;
    ArrayList<Student> empList;
    private static LayoutInflater inflater = null;

    public Show_recordAdapter(Context context,ArrayList<Student> empList)
    {
        context=this.context;
        empList=this.empList;
        inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    }

    public int getCount() {
        // TODO Auto-generated method stub
        return empList.size();
    }

    @Override
    public Object getItem(int position) {
        // TODO Auto-generated method stub
        return empList.get(position);
    }

    @Override
    public long getItemId(int position) 
    {
        // TODO Auto-generated method stub
        return position;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent)
    {
        //final ViewItem item;
        if(convertView==null)

            convertView = inflater.inflate(R.layout.listview_iteams, null);
        //item=new ViewItem();
        TextView UemailTextview=(TextView)convertView.findViewById(R.id.uemail);
        TextView upassTextview=(TextView)convertView.findViewById(R.id.upass);
        TextView UnameTextview=(TextView)convertView.findViewById(R.id.uname);
        TextView UmobileTextview=(TextView)convertView.findViewById(R.id.umobile);
//      convertView.setTag(item);   
//      }
//      else
//      {
//          item=(ViewItem)convertView.getTag();
//      }

        Student student=new Student();
        student=empList.get(position);
        UnameTextview.setText("emailid: "+student.getEmailid());
        upassTextview.setText("password: "+student.getPassword());
        UnameTextview.setText("name: "+student.getName());
        UmobileTextview.setText("mobile: "+student.getMobileno());
        return convertView;
    }

//  private class ViewItem
//  {
//      TextView UemailTextview;
//      TextView upassTextview;
//      TextView UnameTextview;
//      TextView UmobileTextview;
//  }
}

1 个答案:

答案 0 :(得分：2)

Inside Database类getAllrecord（）context1传递的是 null 。

 dbhelper = new Databse_helper(context1);//here context1 is null

您可以尝试在数据库类中将上下文传递给 getAllrecord（上下文context1） 然后可以打电话

studentlist = helper.getAllrecord(Show_record.this);

来自Show_record类的

。希望这有助于解决您的问题。

相关问题
最新问题