问题
This is the first and second activity file of the program i'm developing.. in the first file.. the user is entering a city.. which shall be searched in the database and the corresponding zipcode shall be returned. If the city is not present in the database , the user can enter the city and its zip code in the second activity file.. which is working fine. I'm having problems with the first activity file.. please help.
package com.stdcode;
import java.util.ArrayList;
import java.util.HashMap;
//import com.stdcode.activity2;
import android.app.Activity;
import android.app.ListActivity;
import android.content.ContentProvider;
import android.content.ContentUris;
import android.content.ContentValues;
import android.content.Context;
import android.content.Intent;
import android.content.UriMatcher;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.database.sqlite.SQLiteQueryBuilder;
import android.database.sqlite.SQLiteDatabase.CursorFactory;
import android.net.Uri;
import android.os.Bundle;
import android.view.KeyEvent;
import android.view.View;
import android.view.View.OnClickListener;
import android.util.Log;
import android.widget.ArrayAdapter;
import android.widget.AutoCompleteTextView;
import android.widget.Button;
import android.widget.EditText;
import android.widget.RadioButton;
import android.widget.RadioGroup;
import android.widget.Toast;
import android.widget.RadioGroup.OnCheckedChangeListener;
public class activity1 extends Activity {
EditText city;
Button add,show1;
RadioGroup choose;
String k;
@Override
public void onCreate(Bundle savedInstanceState) {
try
{
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
//final ContentValues values = new ContentValues();
city=(EditText)findViewById(R.id.editText1);
add=(Button)findViewById(R.id.add);
choose=(RadioGroup)findViewById(R.id.radio01);
show1=(Button)findViewById(R.id.button1);
k=city.getText().toString();
createDatabase();
}
catch(Exception e)
{
}
show1.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
db=openOrCreateDatabase(DATABASE_NAME,Context.MODE_PRIVATE,null);
try{
if(k == "CITY")
{
String[] result_columns=new String[]{"_id","CITY","CODE"};
Cursor cursor = db.query(TABLE_NAME, result_columns,
"CITY" +" like '%?%'", new String[]{"k"}, null, null, null);
if(cursor != null)
{
while(cursor.moveToNext())
{
String xnewcode=cursor.getString(1);
Toast.makeText(activity1.this, xnewcode, Toast.LENGTH_LONG).show();
}
}
//db.close();
}}
catch(Exception e)
{
Toast.makeText(activity1.this,"Fault in showing " + e,Toast.LENGTH_LONG).show();
}
}
});
add.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
Intent intent = new Intent(activity1.this,activity2.class);
startActivity(intent);
}
});}
public static final String DATABASE_NAME="myDB.db";
public static final String TABLE_NAME = "citycodes";
private static final String TABLE_CREATE =
"CREATE TABLE " + TABLE_NAME + "(_id integer primary key autoincrement, CITY text not null,CODE text not null);";
SQLiteDatabase db;
public void createDatabase() {
db=openOrCreateDatabase(DATABASE_NAME,Context.MODE_PRIVATE,null);
db.execSQL(TABLE_CREATE);
city.setOnKeyListener(new View.OnKeyListener() {
@Override
public boolean onKey(View v, int keyCode, KeyEvent event) {
//TODO Auto-generated method stub
db=openOrCreateDatabase(DATABASE_NAME,Context.MODE_PRIVATE,null);
try{
if(k == "CITY")
{
String[] result_columns=new String[]{"_id","CITY","CODE"};
Cursor cursor = db.query(TABLE_NAME, result_columns,
"CITY" +"=?", new String[]{"k"}, null, null, null);
cursor.moveToFirst();
String xnewcode=cursor.getString(0);
Toast.makeText(activity1.this, xnewcode, Toast.LENGTH_LONG).show();
cursor.moveToNext();
//if(cursor.moveToFirst()){
//do
//{
//String xnewcity=cursor.getString(0);
//String xnewcode=cursor.getString(1);
//Toast.makeText(activity1.this,xnewcity,Toast.LENGTH_LONG).show();
//Toast.makeText(activity1.this,xnewcode,Toast.LENGTH_LONG).show();
//}while(cursor.moveToNext());
//}
//db.close();
}}
catch(Exception e)
{
Toast.makeText(activity1.this,"Fault in showing " + e,Toast.LENGTH_LONG).show();
}
return true;
}
});
}}
This is the second activity file.. just in case u needed it.
package com.stdcode;
//import static com.stdcode.activity1.DATABASE_NAME;
//import static com.stdcode.activity1.TABLE_NAME;
import android.content.ContentValues;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
public class activity2 extends activity1 {
EditText newcity;
EditText newcode;
Button save,back;
String city1,code1;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main1);
newcity = (EditText) findViewById(R.id.EditText01);
newcode = (EditText) findViewById(R.id.EditText02);
back=(Button)findViewById(R.id.back01);
save=(Button)findViewById(R.id.save01);
back.setOnClickListener(new ClickHandler());
save.setOnClickListener(new ClickHandler());
}
public class ClickHandler implements OnClickListener
{
public void onClick(View v)
{
db=openOrCreateDatabase(DATABASE_NAME,Context.MODE_PRIVATE,null);
try
{
ContentValues newValues=new ContentValues();
if(v == save)
{
city1=newcity.getText().toString();
code1=newcode.getText().toString();
newValues.put("CITY", city1);
newValues.put("CODE", code1);
db.insert(TABLE_NAME, null, newValues);
Toast.makeText(activity2.this,"Values Inserted",Toast.LENGTH_LONG).show();
}
}
catch (Exception e)
{
Toast.makeText(activity2.this,"Error " + e,Toast.LENGTH_LONG).show();
}
back.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
Intent i= new Intent(activity2.this, activity1.class);
startActivity(i);
}
});
}
}
}
回答1:
String xnewcode=cursor.getString(0);
0 is not the good colum, should be 2.
Regards, Stéphane
来源：https://stackoverflow.com/questions/6218395/android-app-which-retrieves-the-zip-code-for-each-city