如何在列表视图中显示来自prepopoulated数据库的多个列？

Question

这是我使用预填充数据库的主要活动。我正在尝试在列表视图中显示行。我的数据库中有五列，我想显示除id之外的所有列。

public class MainActivity extends Activity implements OnClickListener{ 

private IngHelper dbIngHelper = null; 
private Cursor curname=null; 
private SimpleCursorAdapter adapter = null; 


@Override 
public void onCreate(Bundle savedInstanceState) { 

    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_main); 
    ListView myList; 
    myList = (ListView)findViewById(R.id.listView1); 

    dbIngHelper = new IngHelper(this); 
    dbIngHelper.createDB(); 
    dbIngHelper.openDB(); 


    fillData(); 
} 


public void fillData(){ 

    //ListView myList; 
    ListView myList; 
    myList = (ListView)findViewById(R.id.listView1); 
    curname=dbIngHelper.getCursor(); 
    startManagingCursor(curname); 
    String[] columns = new String[] { 
      IngHelper.COLUMN_ID, 
      IngHelper.COLUMN_NAME, 
      IngHelper.COLUMN_NATURE, 
      IngHelper.COLUMN_SECTION, 
      IngHelper.COLUMN_PENALTY 
     }; 

    int[] to = new int[] { 
      R.id.id, 
      R.id.name, 
      R.id.nature, 
      R.id.penalty, 
      R.id.section 
      }; 

    adapter = new SimpleCursorAdapter(
      this, R.layout.activity_main, 
      curname, 
      columns, 
      to); 



    myList.setAdapter(adapter); 



myList.setOnItemClickListener(new OnItemClickListener() { 
    public void onItemClick(AdapterView<?> listView, View view,int position, long id) { 
    //Get the cursor, positioned to the corresponding row in the result set 
    // Cursor cursor = (Cursor) listView.getItemAtPosition(position); 


    } 
}); 
} 



@Override 
public boolean onCreateOptionsMenu(Menu menu) { 
    getMenuInflater().inflate(R.menu.activity_main, menu); 
    return true; 
} 

class IngAdapter extends CursorAdapter{ 
    @SuppressWarnings("deprecation") 
    IngAdapter(Cursor c){ 
     super(MainActivity.this,c); 
    } 

    @Override 
    public void bindView(View row, Context ctxt, Cursor c) { 
     // TODO Auto-generated method stub 

     IngHolder holder=(IngHolder)row.getTag(); 
     holder.populateFrom(c,dbIngHelper); 


    } 

    @Override 
    public View newView(Context cxtx, Cursor c, ViewGroup parent) { 
     // TODO Auto-generated method stub 
     LayoutInflater inf = getLayoutInflater(); 
     View row=inf.inflate(R.layout.row, parent, false); 
     IngHolder holder = new IngHolder(row); 
     row.setTag(holder); 
     return(row); 
    } 

} 

static class IngHolder{ 
    private TextView name=null; 
    // private TextView nature=null; 
    //private TextView section=null; 
    //private TextView penalty=null; 

    IngHolder(View row){ 

     name=(TextView)row.findViewById(R.id.name); 

    } 

    void populateFrom(Cursor c,IngHelper r){ 

     name.setText(r.getName(c)); 


    } 


} 

@Override 
public void onClick(View arg0) { 
    // TODO Auto-generated method stub 

} 
} 

这是数据库类IngHelper.java

public class IngHelper extends SQLiteOpenHelper{ 


private static final String DATABASE_PATH =  "//data//data//com.example.db//databases//"; 
private static final String DATABASE_NAME = "traffic.sqlite"; 
private static final int SCHEMA_VERSION = 1; 
public static final String TABLE_NAME="mumbai"; 
public static final String COLUMN_ID="_id"; 
public static final String COLUMN_NAME="name"; 
public static final String COLUMN_NATURE="nature"; 
public static final String COLUMN_SECTION="section"; 
public static final String COLUMN_PENALTY="penalty"; 


public SQLiteDatabase dbSqlite; 

private final Context myCnt; 

public IngHelper (Context context) 
{ 
    super(context, DATABASE_NAME, null, SCHEMA_VERSION); 
    this.myCnt=context; 
} 

@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 

} 

public void createDB(){ 

    boolean dbExist = DBExist(); 

    if(!dbExist){ 

     this.getReadableDatabase(); 

     copyDBFromResource(); 
    } 
} 

private boolean DBExist(){ 
    SQLiteDatabase db = null; 

    try{ 
     String dbPath = DATABASE_PATH + DATABASE_NAME; 
     db = SQLiteDatabase.openDatabase(dbPath, null,  SQLiteDatabase.OPEN_READWRITE); 
     db.setLocale(Locale.getDefault()); 
     db.setLockingEnabled(true); 
     db.setVersion(1); 
    }catch(SQLiteException e){ 
     Log.e("SqlHelper", "db nt found"); 
     } 

    return db != null ? true : false; 
} 

private void copyDBFromResource(){ 
    InputStream iS =null; 
    OutputStream oS = null; 
    String dbFilePath = DATABASE_PATH + DATABASE_NAME; 

    try{ 
     iS = myCnt.getAssets().open(DATABASE_NAME); 

     oS = new FileOutputStream(dbFilePath); 

     byte[] buffer = new byte[1024]; 
     int length; 
     while((length=iS.read(buffer))>0){ 
      oS.write(buffer, 0, length); 
     } 

     oS.flush(); 
     oS.close(); 
     iS.close(); 
    }catch(IOException e){ 
     throw new Error("Prob copyin db from resource file."); 
    } 

} 

public void openDB()throws SQLException { 
    String myPath = DATABASE_PATH + DATABASE_NAME; 
    dbSqlite = SQLiteDatabase.openDatabase(myPath, null, SQLiteDatabase.OPEN_READWRITE); 
} 

@Override 
public synchronized void close() { 
    // TODO Auto-generated method stub 
    if(dbSqlite != null) 
    { 
     dbSqlite.close(); 
    } 
    super.close(); 
} 


public Cursor getCursor(){ 
    SQLiteQueryBuilder qBuilder = new SQLiteQueryBuilder(); 
    qBuilder.setTables(TABLE_NAME); 
    String[] asColmToRetrn = new String[] {COLUMN_ID, COLUMN_NAME, COLUMN_NATURE, COLUMN_SECTION, COLUMN_PENALTY}; 

    Cursor mCur = qBuilder.query(dbSqlite, asColmToRetrn, null, null, null, null, null); 

    if (mCur != null) { 
     mCur.moveToFirst(); 
     } 
     return mCur; 

    } 



public String getName(Cursor c){ 
    return(c.getString(1)); 


} 

} 

有两个XML文件。这是activity_main.xml ...它有一个列表视图。

<RelativeLayout 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" > 



<ListView 
    android:id="@+id/listView1" 
    android:layout_width="match_parent" 
    android:layout_height="wrap_content" 
    android:layout_alignParentLeft="true" > 

</ListView> 

</RelativeLayout> 

另一种布局是row.xml文件。在这里，我正在为我的数据库中的每一列创建一个文本视图。

<?xml version="1.0" encoding="utf-8"?> 
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 
    android:layout_width="match_parent" 
    android:layout_height="match_parent" 
    android:orientation="vertical" > 

<TextView 
    android:id="@+id/id" 
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 
    android:textColor="#000000" 
    android:text="TextView" /> 

<TextView 
    android:id="@+id/name" 
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 
    android:textColor="#000000" 
    android:text="TextView" /> 

<TextView 
    android:id="@+id/nature" 
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 
    android:textColor="#000000" 
    android:text="TextView" /> 

<TextView 
    android:id="@+id/section" 
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 
    android:textColor="#000000" 
    android:text="TextView" /> 

<TextView 
    android:id="@+id/penalty" 
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 
    android:textColor="#000000" 

    android:text="TextView" /> 

</LinearLayout> 

我得到一个空白列表作为输出与每行的列表条目，但数据无法看到。请给出一些建议以解决问题

Answer 1

如果要显示所有列值，则必须创建自定义适配器。请参阅here和Vogella tutorial。