将行插入SQLite数据库时Android App不会崩溃

Question

Hi I'm new to Android development and am trying to make an app that takes a users first and last name, zip code, age and sex add them to a SQLite database and then display it on the next page. I have tried many tutorial for this but have had little results. After entering the data in the EditText, pressing the submit button causes the android to crash Any help would be appreciated. This is my main activity where the user enters their data

package com.example.votesmart;


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

public class Zip extends Activity {

    private static final int TIME_ENTRY_REQUEST_CODE = 1;

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

    }

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

    public void onSubmit(View view){
        Intent intent = new Intent(this, EditProfile.class);
        startActivityForResult(intent, TIME_ENTRY_REQUEST_CODE);

        EditText firstView = (EditText)findViewById(R.id.fname_input);
        intent.putExtra("first", firstView.getText().toString());

        EditText lastView = (EditText)findViewById(R.id.lname_input);
        intent.putExtra("last", lastView.getText().toString());

        EditText zipView = (EditText)findViewById(R.id.zipcode_input);
        intent.putExtra("zip", zipView.getText().toString());

        EditText ageView = (EditText)findViewById(R.id.age_input);
        intent.putExtra("age", ageView.getText().toString());

        EditText sexView = (EditText)findViewById(R.id.sex_input);
        intent.putExtra("sex", sexView.getText().toString());
    }


}

its layout

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".Zip"
    android:orientation="vertical" >

    <TextView
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="First Name" />

     <EditText
        android:id="@+id/fname_input"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"/>

    <TextView
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="Last Name" />

     <EditText
        android:id="@+id/lname_input"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        />

    <TextView
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="Zip Code" />

    <EditText
        android:id="@+id/zipcode_input"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"/>

    <TextView
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="Age" />

     <EditText
        android:id="@+id/age_input"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"/>

     <TextView
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="Sex" />

     <EditText
        android:id="@+id/sex_input"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"/>

    <Button
        android:id="@+id/submit"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="Submit"
        android:onClick="onSubmit" />

</LinearLayout>

the next page to display the data

package com.example.votesmart;


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

public class EditProfile extends Activity {
    VSAdapter vsAdapter;

    public static final int TIME_ENTRY_REQUEST_CODE = 1;
    private DatabaseHandler databaseHelper;
    public void onCreate(Bundle savedInstanceState){
        super.onCreate(savedInstanceState);
        setContentView(R.layout.edit_profile);

        databaseHelper = new DatabaseHandler(this);

        ListView listView = (ListView)findViewById(R.id.list);
        vsAdapter = new VSAdapter(this, databaseHelper.getAllRecords());
        listView.setAdapter(vsAdapter); 
    }

    public void onBack (View view){
        finish();
    }

    protected void onActivityResult(int requestCode, int resultCode, Intent data){
        if (requestCode == TIME_ENTRY_REQUEST_CODE){
            if (resultCode == RESULT_OK){

                String first = data.getStringExtra("first");
                String last = data.getStringExtra("last");
                String zip = data.getStringExtra("zip");
                String age = data.getStringExtra("age");
                String sex = data.getStringExtra("sex");

                databaseHelper.addVoter(first, last, zip, age, sex);
                //vsAdapter.changeCursor(databaseHelper.getAllRecords());

                //databaseHelper.addVoter(first, last, zip, age, sex);

            }
            }
        }
    }

my adapter

package com.example.votesmart;

import android.content.Context;
import android.database.Cursor;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.CursorAdapter;
import android.widget.TextView;

public class VSAdapter extends CursorAdapter {

    public VSAdapter(Context context, Cursor cursor){
        super(context, cursor);
    }

    @Override
    public void bindView(View view, Context context, Cursor cursor) {
        // TODO Auto-generated method stub
        TextView nameTextView = (TextView) view.findViewById(R.id.first_view);
        nameTextView.setText(cursor.getString(cursor.getColumnIndex("1")));
        TextView lastTextView = (TextView) view.findViewById(R.id.last_view);
        lastTextView.setText(cursor.getString(cursor.getColumnIndex("2")));
        TextView zipTextView = (TextView) view.findViewById(R.id.zip_view);
        zipTextView.setText(cursor.getString(cursor.getColumnIndex("3")));
        TextView ageTextView = (TextView) view.findViewById(R.id.age_view);
        ageTextView.setText(cursor.getString(cursor.getColumnIndex("4")));
        TextView sexTextView = (TextView) view.findViewById(R.id.sex_view);
        sexTextView.setText(cursor.getString(cursor.getColumnIndex("5")));
    }

    public View newView(Context context, Cursor cursor, ViewGroup parent) {
        // TODO Auto-generated method stub
        LayoutInflater inflater = LayoutInflater.from(parent.getContext());
        View view = inflater.inflate(R.layout.zip_list_item,  parent, false);


        return view;
    }

}
and finally my database class
private class DatabaseOpenHelper extends SQLiteOpenHelper{
        DatabaseOpenHelper(Context context){
        super(context, DATABASE_NAME, null, DATABASE_VERSION);
        }

        @Override
        public void onCreate(SQLiteDatabase db) {
            // TODO Auto-generated method stub
            String CREATE_VOTERS_TABLE = "create table " + TABLE_NAME + "(" + KEY_ID + " integer primary key, " + KEY_FIRST + " text," + KEY_LAST + " text," + KEY_ZIP + " text," + KEY_AGE + " text," + KEY_SEX + "text" ;
            db.execSQL(
                    CREATE_VOTERS_TABLE
                    );
        }

        @Override
        public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
            // TODO Auto-generated method stub
            db.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME);
            onCreate(db);
        }
    }

        public void addVoter(String first, String last, String zip, String age, String sex){
            //public void addVoter{Voter voter){
            ContentValues values = new ContentValues();
            values.put(KEY_FIRST, first);
            values.put(KEY_LAST, last);
            values.put(KEY_ZIP, zip);
            values.put(KEY_AGE, age);
            values.put(KEY_SEX, sex);

            db.insert(TABLE_NAME, null, values);

                //return db.update(TABLE_NAME, values, KEY_ID + " = ?", new String[] {String.valueOf(voter.getId()) });
            }
        public Cursor getAllRecords(){
            return db.rawQuery(
                    "select * from " + TABLE_NAME,
                    null
                    );
        }
}

Once again any help is greatly appreciated, Thanks!

Answer 1

There are a few issues with this,

public void onSubmit(View view){
        Intent intent = new Intent(this, EditProfile.class);


        EditText firstView = (EditText)findViewById(R.id.fname_input);
        intent.putExtra("first", firstView.getText().toString());

        EditText lastView = (EditText)findViewById(R.id.lname_input);
        intent.putExtra("last", lastView.getText().toString());

        EditText zipView = (EditText)findViewById(R.id.zipcode_input);
        intent.putExtra("zip", zipView.getText().toString());

        EditText ageView = (EditText)findViewById(R.id.age_input);
        intent.putExtra("age", ageView.getText().toString());

        EditText sexView = (EditText)findViewById(R.id.sex_input);
        intent.putExtra("sex", sexView.getText().toString());
        startActivityForResult(intent, TIME_ENTRY_REQUEST_CODE);
    }

You need to add the data before sending it. The method in which you are using onActivityResult is also wrong,

In your oncreate method of the EditProfile class, put the following

Intent data = getIntent().getExtras();

String first = data.getStringExtra("first");
String last = data.getStringExtra("last");
String zip = data.getStringExtra("zip");
String age = data.getStringExtra("age");
String sex = data.getStringExtra("sex");

databaseHelper.addVoter(first, last, zip, age, sex);

Ideally this should be on a thread but yeah.

Answer 2

In this block of code:

public void onSubmit(View view){
        Intent intent = new Intent(this, EditProfile.class);
        startActivityForResult(intent, TIME_ENTRY_REQUEST_CODE);

you are starting your activity in the 3rd line, but then after that you are "adding data" to the intent... the intent was consumed with "startActivity". Put that at the bottom of that block.

And you don't get the intent data in the other Activity's "onResult" - that is where you set the activity's results before you destroy it. The intent data collected needs be before the activity is displayed - onCreate, onStart or onResume. OnCreate will do it once. The others are for situations where you might want to recycle the activity (like add another voter after it has already started). But you need to check for dupes.