我有两项活动： -Term活动：listview - 详细活动：textview
我想在我的DetailActivity中显示一个textView，来自我的数据库，关于onclickitem的上一个活动，TermActivity。
其实我只能得到id或“Android.database.sqlite.SQLiteCursor@45cabae8”所以我认为我的代码是错的。
DetailActivity
package com.example.afpcv2;
import com.example.afpcv2.DetailActivity;
import com.example.afpcv2.SocActivity;
import com.example.afpcv2.R;
import com.example.afpcv2.SocActivity.SocHolder;
import com.example.afpcv2.TermActivity.TermAdapter;
import com.example.afpcv2.TermActivity.TermHolder;
import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.database.Cursor;
import android.os.Bundle;
import android.support.v4.widget.CursorAdapter;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;
public class DetailActivity extends Activity{
String passedVar=null;
private TextView passedView=null;
private Cursor ourCursor = null;
private SoclistHelper dbSocHelper = null;
private DetailAdapter adapter=null;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.act3);
passedVar=getIntent().getStringExtra(TermActivity.ID_EXTRA);
passedView=(TextView)findViewById(R.id.bookText);
dbSocHelper=new SoclistHelper(this);
ourCursor=dbSocHelper.getDetailByTerm(passedVar);
startManagingCursor(ourCursor);
adapter=new DetailAdapter(ourCursor);
if(ourCursor != null){
if(ourCursor.moveToFirst()){
String value = ourCursor.getString(ourCursor.getColumnIndex("Grade1"));
passedView.setText("Definition " + value);
}
}
}
class DetailAdapter extends CursorAdapter {
DetailAdapter(Cursor c) {
super(DetailActivity.this, c);
}
public void bindView(View row, Context ctxt,
Cursor c) {
DetailHolder holder=(DetailHolder)row.getTag();
holder.populateFrom(c, dbSocHelper);
}
public View newView(Context ctxt, Cursor c,
ViewGroup parent) {
LayoutInflater inflater=getLayoutInflater();
View row=inflater.inflate(R.layout.row2, parent, false);
DetailHolder holder=new DetailHolder(row);
row.setTag(holder);
return(row);
}
}
static class DetailHolder {
private TextView name=null;
DetailHolder(View row) {
name=(TextView)row.findViewById(R.id.bookText);
}
void populateFrom(Cursor c, SoclistHelper r) {
name.setText(r.getName(c));
}
}
}
学期活动
package com.example.afpcv2;
import com.example.afpcv2.TermActivity;
import com.example.afpcv2.SocActivity;
import com.example.afpcv2.R;
import com.example.afpcv2.SocActivity.SocHolder;
import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.database.Cursor;
import android.os.Bundle;
import android.support.v4.widget.CursorAdapter;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.ListView;
import android.widget.TextView;
public class TermActivity extends Activity{
public final static String ID_EXTRA="com.example.afpcv2._ID";
String passedVar=null;
private TextView passedView=null;
private SoclistHelper dbSocHelper = null;
private Cursor ourCursor = null;
private TermAdapter adapter=null;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.act2);
passedVar=getIntent().getStringExtra(SocActivity.ID_EXTRA);
ListView myListView = (ListView)findViewById(R.id.myListView);
dbSocHelper=new SoclistHelper(this);
ourCursor=dbSocHelper.getTermBySoc(passedVar);
startManagingCursor(ourCursor);
adapter=new TermAdapter(ourCursor);
myListView.setAdapter(adapter);
myListView.setOnItemClickListener(onListClick);
}
private AdapterView.OnItemClickListener onListClick=new AdapterView.OnItemClickListener() {
public void onItemClick(AdapterView<?> parent,
View view, int position,
long id)
{
Intent i=new Intent(TermActivity.this, DetailActivity.class);
i.putExtra(ID_EXTRA, String.valueOf(id));
startActivity(i);
}
};
class TermAdapter extends CursorAdapter {
TermAdapter(Cursor c) {
super(TermActivity.this, c);
}
public void bindView(View row, Context ctxt,
Cursor c) {
TermHolder holder=(TermHolder)row.getTag();
holder.populateFrom(c, dbSocHelper);
}
public View newView(Context ctxt, Cursor c,
ViewGroup parent) {
LayoutInflater inflater=getLayoutInflater();
View row=inflater.inflate(R.layout.row2, parent, false);
TermHolder holder=new TermHolder(row);
row.setTag(holder);
return(row);
}
}
static class TermHolder {
private TextView name=null;
TermHolder(View row) {
name=(TextView)row.findViewById(R.id.bookText);
}
void populateFrom(Cursor c, SoclistHelper r) {
name.setText(r.getName(c));
}
}
}
我的DatabaseHelper
package com.example.afpcv2;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import android.content.Context;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteException;
import android.database.sqlite.SQLiteOpenHelper;
import android.database.sqlite.SQLiteQueryBuilder;
public class SoclistHelper extends SQLiteOpenHelper{
//The Android's default system path of your application database.
private static String DB_PATH = "/data/data/com.example.afpcv2/databases/";
private static String DB_NAME = "soclist.db";
private static final String TABLE_NAME = "Soc";
private static final String COLUMN_ID = "_id";
public static final String COLUMN_TITLE = "soc_name";
private static final String SECOND_TABLE_NAME = "Term";
private static final String SECOND_COLUMN_ID = "_id";
public static final String SECOND_COLUMN_TITLE = "term_name";
private static final String THIRD_TABLE_NAME = "Detail";
private static final String THIRD_COLUMN_ID = "_id";
public static final String THIRD_COLUMN_TITLE = "Grade1";
private SQLiteDatabase myDataBase;
private final Context myContext;
/**
* Constructor
* Takes and keeps a reference of the passed context in order to access to the application assets and resources.
* @param context
*/
public SoclistHelper(Context context) {
super(context, DB_NAME, null, 1);
this.myContext = context;
}
public void createDataBase() throws IOException{
boolean dbExist = checkDataBase();
if(dbExist){
//do nothing - database already exist
}else{
//By calling this method and empty database will be created into the default system path
//of your application so we are gonna be able to overwrite that database with our database.
this.getReadableDatabase();
try {
copyDataBase();
} catch (IOException e) {
throw new Error("Error copying database");
}
}
}
/**
* Check if the database already exist to avoid re-copying the file each time you open the application.
* @return true if it exists, false if it doesn't
*/
private boolean checkDataBase(){
SQLiteDatabase checkDB = null;
try{
String myPath = DB_PATH + DB_NAME;
checkDB = SQLiteDatabase.openDatabase(myPath, null, SQLiteDatabase.OPEN_READONLY);
}catch(SQLiteException e){
//database does't exist yet.
}
if(checkDB != null){
checkDB.close();
}
return checkDB != null ? true : false;
}
/**
* Copies your database from your local assets-folder to the just created empty database in the
* system folder, from where it can be accessed and handled.
* This is done by transfering bytestream.
* */
private void copyDataBase() throws IOException{
//Open your local db as the input stream
InputStream myInput = myContext.getAssets().open(DB_NAME);
// Path to the just created empty db
String outFileName = DB_PATH + DB_NAME;
//Open the empty db as the output stream
OutputStream myOutput = new FileOutputStream(outFileName);
//transfer bytes from the inputfile to the outputfile
byte[] buffer = new byte[1024];
int length;
while ((length = myInput.read(buffer))>0){
myOutput.write(buffer, 0, length);
}
//Close the streams
myOutput.flush();
myOutput.close();
myInput.close();
}
public void openDataBase() throws SQLException{
//Open the database
String myPath = DB_PATH + DB_NAME;
myDataBase = SQLiteDatabase.openDatabase(myPath, null, SQLiteDatabase.OPEN_READONLY);
}
@Override
public synchronized void close() {
if(myDataBase != null)
myDataBase.close();
super.close();
}
@Override
public void onCreate(SQLiteDatabase db) {
// TODO Auto-generated method stub
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
// TODO Auto-generated method stub
}
// Add your public helper methods to access and get content from the database.
// You could return cursors by doing "return myDataBase.query(....)" so it'd be easy
// to you to create adapters for your views.
public Cursor getCursor() {
SQLiteQueryBuilder queryBuilder = new SQLiteQueryBuilder();
queryBuilder.setTables(TABLE_NAME);
String[] asColumnsToReturn = new String [] { COLUMN_ID, COLUMN_TITLE};
//make sure get search by string pass correctly
Cursor mCursor = queryBuilder.query(myDataBase, asColumnsToReturn, null,
null, null, null, "soc_name ASC");
return mCursor;
}
public String getName(Cursor c) {
return(c.getString(1));
}
public Cursor getTermBySoc(String id) {
String[] args={id};
return(getReadableDatabase()
.rawQuery("SELECT _id, term_name FROM Term WHERE soc_id=?",
args));
}
public Cursor getDetailByTerm(String id) {
String[] args={id};
return(getReadableDatabase()
.rawQuery("SELECT _id, Term_name FROM Detail WHERE Term_id=?",
args));
}
public Cursor getDetailByTerm2(String id) {
String[] args={id};
return(getReadableDatabase()
.rawQuery("SELECT _id, Grade1 FROM Detail WHERE Term_id=?",
args));
}
public Cursor getDetailByTerm3(String id) {
String[] args={id};
return(getReadableDatabase()
.rawQuery("SELECT _id, Grade2 FROM Detail WHERE Term_id=?",
args));
}
public Cursor getDetailByTerm4(String id) {
String[] args={id};
return(getReadableDatabase()
.rawQuery("SELECT _id, Grade3 FROM Detail WHERE Term_id=?",
args));
}
public Cursor getDetailByTerm5(String id) {
String[] args={id};
return(getReadableDatabase()
.rawQuery("SELECT _id, Grade4 FROM Detail WHERE Term_id=?",
args));
}
public Cursor getDetailByTerm6(String id) {
String[] args={id};
return(getReadableDatabase()
.rawQuery("SELECT _id, Grade5 FROM Detail WHERE Term_id=?",
args));
}
}
告诉我你是否需要更多信息。 谢谢你的帮助！
答案 0 :(得分：0)
问题出现在这一行：passedView.setText("Definition "+ourCursor);
您必须从要从光标
显示的列中获取值if(ourCursor != null){
if(ourCursor.moveToFirst()){
string value = ourCursor.getString(ourCursor.getColumnIndex("term_name"));
passedView.setText("Definition " + value);
}
}