如何打开另一个活动，当我点击listItem使用SQLite数据库和显示在TextView使用android的意图

Question

在我的项目中有三个java类它们是:MainActivity.java,Activity2.java和DataBaseHelper.java。使用两个XML布局。现在我想把数据从mainactivity传递到Activity2，当我点击activity_main布局的listtiitem，这将显示在act2布局的TextViews上。在这里，我使用了一个sqlitedatase与ID, NAME和DESC作为列名，我的问题是，一旦我点击每个列表视图，我就无法在TextView上显示NAME和DESC，我只能显示ID。为了解决这个问题，我已经搜索了几天了，但我没有得到任何东西。我知道这是一个愚蠢而简单的问题，但如果你能分享任何信息和帮助，那将是非常伟大的。谢谢你！我使用了下面的代码:

MainActivity.java:

public final static String EXTRA_NAME="com.example.verena.NAME";
   public final static String EXTRA_DESC="com.example.verena.DESC";

     private AdapterView.OnItemClickListener onListClick = new AdapterView.OnItemClickListener() {
            private AdapterView listView;
            public AdapterView getListView() {
                return listView;
            }
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                /* TextView viewName = (TextView)view.findViewById(R.id.passed);
                 TextView viewDes = (TextView)view.findViewById(R.id.passeddes);
                 String sName = viewName.getText().toString();
                String sDesc = viewDes.getText().toString();
                i.putExtra(EXTRA_NAME,sName);
                i.putExtra(EXTRA_DESC, sDesc);*/
                //2detail

                Intent i = new Intent(MainActivity.this, Activity2.class);
                i.putExtra(EXTRA_NAME, String.valueOf(id));

                //
                Toast.makeText(getApplicationContext(), "Saved Data", Toast.LENGTH_LONG).show();
                int pos = this.getListView().getSelectedItemPosition();
                Cursor c = (Cursor) this.getListView().getAdapter().getItem(pos);
                Bundle b = new Bundle();
                b.putString(EXTRA_DESC, c.getString(0));
                b.putString(EXTRA_NAME, c.getString(1));
                i.setClass(MainActivity.this, Activity2.class);
                i.putExtras(b);
                /* TextView desv= (TextView)findViewById(R.id.passeddes);
                String  desS = desv.getText().toString();
                i.putExtra(EXTRA_DESC, desS);*/
               /* TextView viewDes = (TextView)view.findViewById(R.id.passeddes);
                String sDesc = viewDes.getText().toString();
                i.putExtra(EXTRA_DESC, sDesc);*/
       /*TextView viewDes = (TextView)view.findViewById(R.id.passeddes);
                String sDesc = viewDes.getText().toString();
                i.putExtra(EXTRA_DESC, sDesc);*/
                startActivity(i);
            }

Activity2.java

String passedVar=null;
private TextView passedNameView = null;
String passedVardes = null;
private TextView passedViewDescView = null;
 @Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.act2);
    passedVar = getIntent().getStringExtra(MainActivity.EXTRA_NAME);
    passedVardes= getIntent().getStringExtra(MainActivity.EXTRA_DESC);
    passedView=(TextView)findViewById(R.id.passed);
    passedViewDesc=(TextView)findViewById(R.id.passeddes);
    passedNameView.setText("you have click on:" + passedVar);
    passedViewDescView.setText("you hv click on:"+passedVardes);
}

DatabaseHelper.java

    public class DatabaseHelper extends SQLiteOpenHelper {
    public static String DB_PATH = "/data/data/com.example.verena/databases/";
    public static String DB_NAME = "dic.sqlite";
    public static final int DB_VERSION = 1;
    public static final String TB_USER = "Users";
    private SQLiteDatabase myDB;
    private Context context;
    public DatabaseHelper(Context context) {
        super(context, DB_NAME, null, DB_VERSION);  
        this.context = 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
    }
    @Override
    public synchronized void close(){
        if(myDB!=null){
            myDB.close();
        }
        super.close();
    }
    public List<String> getAllUsers(){
        List<String> listUsers = new ArrayList<String>();
        SQLiteDatabase db = this.getWritableDatabase();
        Cursor c;

        try {
            c = db.rawQuery("SELECT * FROM " + TB_USER , null);
            if(c == null) return null;
            String name;
            c.moveToFirst();
            do {            
                name = c.getString(1);          
                listUsers.add(name);
            } while (c.moveToNext()); 
            c.close();
        } catch (Exception e) {
            Log.e("tle99", e.getMessage());
        }

        db.close();
        return listUsers;
    }

    /***
     * Open database
     * @throws SQLException
     */
    public void openDataBase() throws SQLException{
        String myPath = DB_PATH + DB_NAME;
        //myDB = SQLiteDatabase.openDatabase(myPath, null, SQLiteDatabase.OPEN_READWRITE);
        myDB = SQLiteDatabase.openDatabase(myPath, null,SQLiteDatabase.OPEN_READWRITE);
    }
    public void copyDataBase() throws IOException{
        try {
            InputStream myInput = context.getAssets().open(DB_NAME);
            String outputFileName = DB_PATH + DB_NAME;
            OutputStream myOutput = new FileOutputStream(outputFileName);
            byte[] buffer = new byte[1024];
            int length;
            while((length = myInput.read(buffer))>0){
                myOutput.write(buffer, 0, length);
            }
            myOutput.flush();
            myOutput.close();
            myInput.close();
        } catch (Exception e) {
            Log.e("tle99 - copyDatabase", e.getMessage());
        }
    }
    /***
     * Check if the database doesn't exist on device, create new one
     * @throws IOException
     */
    public void createDataBase() throws IOException {
        boolean dbExist = checkDataBase();      
        if (dbExist) {
        } else {
            this.getReadableDatabase();
            try {
                copyDataBase();
            } catch (IOException e) {
                Log.e("tle99 - create", e.getMessage());
            }
        }
    }
    // ---------------------------------------------
    // PRIVATE METHODS
    // ---------------------------------------------
    /***
     * Check if the database is exist on device or not
     * @return
     */
    private boolean checkDataBase() {
        SQLiteDatabase tempDB = null;
        try {
            String myPath = DB_PATH + DB_NAME;
            tempDB = SQLiteDatabase.openDatabase(myPath, null,
                    SQLiteDatabase.OPEN_READWRITE);
        } catch (SQLiteException e) {
            Log.e("tle99 - check", e.getMessage());
        }
        if (tempDB != null)
            tempDB.close();
        return tempDB != null ? true : false;
    }
}

Answer 1

将id作为字符串、名称和描述传递到一个bundle中。你需要从intent中获取bundle并从那个bundle中获取你的名字和名称。另一种方法是，您可以将id、name和desc作为字符串传递，如下所示:

在你的MainActivity.java:

// New Intent
Intent i = new Intent(MainActivity.this, Activity2.class);
// Put Extras
// Put your id
i.putExtra("id", String.valueOf(id));
int pos = this.getListView().getSelectedItemPosition();
Cursor c = (Cursor) this.getListView().getAdapter().getItem(pos);
// Put Name
i.putExtra(EXTRA_NAME, c.getString(0));
// Put Description
i.putExtra(EXTRA_DESC, c.getString(1));
i.setClass(MainActivity.this, Activity2.class);
startActivity(i);

要在Activity2.java中获得id，请在onCreate方法中放入以下行:

String passedVarid = getIntent().getStringExtra("id");