Question

这是myclass eyehelper，它从文本文件中预先添加数据库

    public class EyeHelper extends SQLiteOpenHelper {
      private static final String TAG = "EyeDatabase";
      //private static final String DB_DIR = "/data/data/test.eyedb/databases/";
      private static final String DB_NAME="eyeDB.sqlite";
      //private static String DB_PATH = DB_DIR + DB_NAME;
      private static final int SCHEMA_VERSION=1;
      private final Context myContext = null;
      private SQLiteDatabase mDatabase;

  public EyeHelper(Context context) {
    super(context, DB_NAME, null, SCHEMA_VERSION);
  }



  @Override
  public void onCreate(SQLiteDatabase db) {
    db.execSQL("CREATE TABLE DiseaseTable (_id INTEGER PRIMARY KEY AUTOINCREMENT, Disease TEXT NOT NULL, Definition TEXT NOT NULL, Remedy TEXT NOT NULL);");
    db.execSQL("INSERT INTO DiseaseTable VALUES(1,'Nilsen', 'Johan', 'Bakken 2');");
    loadDB();
  }
  private void loadDB() {
      new Thread(new Runnable() {
          public void run() {
              try {
                  loadWords();
              } catch (IOException e) {
                  throw new RuntimeException(e);
              }
          }
      }).start();
  }

  private void loadWords() throws IOException {
      Log.d(TAG, "Loading words...");
      final Resources resources = myContext.getResources();
      InputStream inputStream = resources.openRawResource(R.raw.dbtest);
      BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream));

      try {
          String line;
          while ((line = reader.readLine()) != null) {
              String[] strings = TextUtils.split(line, "-");
              if (strings.length < 3) continue;
              long id = addWord(strings[0].trim(), strings[1].trim(), strings[2].trim());
              if (id < 0) {
                  Log.e(TAG, "unable to add word: " + strings[0].trim());
              }
          }
      } finally {
          reader.close();
      }
      Log.d(TAG, "DONE loading words.");
  }

  /**
   * Add a word to the dictionary.
   * @return rowId or -1 if failed
   */
  public long addWord(String disease, String definition, String remedy) {
      ContentValues cv = new ContentValues();
      cv.put("disease", disease);
      cv.put("definition", definition);
      cv.put("remedy", remedy);
      return mDatabase.insert("DiseaseTable", null, cv);
  }


  @Override
  public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
      Log.w(TAG, "Upgrading database from version " + oldVersion + " to "
              + newVersion + ", which will destroy all old data");
      db.execSQL("DROP TABLE IF EXISTS DiseaseTable");
      onCreate(db);
  }

  public Cursor getAll() {
    return(getReadableDatabase()
            .rawQuery("SELECT * FROM DiseaseTable",
                      null));
  }

  public void insert(String disease, String definition,
                     String remedy) {
    ContentValues cv=new ContentValues();

    cv.put("disease", disease);
    cv.put("definition", definition);
    cv.put("remedy", remedy);


    getWritableDatabase().insert("Disease", "disease", cv);
  }

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

  public String getDefinition(Cursor c) {
    return(c.getString(2));
  }

  public String getRemedy(Cursor c) {
    return(c.getString(3));
  }
}

这是我的主要活动

public class EyeDBActivity extends TabActivity {
  Cursor model=null;
  EyeAdapter adapter=null;
  TextView disease;
  TextView definition;
  TextView remedy;
  EyeHelper helper=null;

  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    helper=new EyeHelper(this);

    disease=(TextView)findViewById(R.id.disease);
    definition=(TextView)findViewById(R.id.definition);
    remedy=(TextView)findViewById(R.id.remedy);

    //sButton save=(Button)findViewById(R.id.save);

    //save.setOnClickListener(onSave);

    ListView list=(ListView)findViewById(R.id.list);

    model=helper.getAll();
    startManagingCursor(model);
    adapter=new EyeAdapter(model);
    list.setAdapter(adapter);

    TabHost.TabSpec spec=getTabHost().newTabSpec("tag1");

    spec.setContent(R.id.list);
    spec.setIndicator("Search", getResources()
                                .getDrawable(R.drawable.list));
    getTabHost().addTab(spec);

    spec=getTabHost().newTabSpec("tag2");
    spec.setContent(R.id.details);
    spec.setIndicator("Information", getResources()
                                  .getDrawable(R.drawable.restaurant));
    getTabHost().addTab(spec);

    getTabHost().setCurrentTab(0);

    list.setOnItemClickListener(onListClick);
  }

  @Override
  public void onDestroy() {
    super.onDestroy();

    helper.close();
  }

  /*private View.OnClickListener onSave=new View.OnClickListener() {
    public void onClick(View v) {
      String type=null;

      switch (types.getCheckedRadioButtonId()) {
        case R.id.sit_down:
          type="sit_down";
          break;
        case R.id.take_out:
          type="take_out";
          break;
        case R.id.delivery:
          type="delivery";
          break;
      }

      helper.insert(name.getText().toString(),
                    address.getText().toString(), type,
                    notes.getText().toString());
      model.requery();
    }
  };*/

  private AdapterView.OnItemClickListener onListClick=new AdapterView.OnItemClickListener() {
    public void onItemClick(AdapterView<?> parent,
                              View view, int position,
                              long id) {
      model.moveToPosition(position);
      disease.setText(helper.getDisease(model));
      definition.setText(helper.getDefinition(model));
      remedy.setText(helper.getRemedy(model));
      getTabHost().setCurrentTab(1);
    }
  };

  class EyeAdapter extends CursorAdapter {
    EyeAdapter(Cursor c) {
      super(EyeDBActivity.this, c);
    }

    @Override
    public void bindView(View row, Context ctxt,
                         Cursor c) {
      EyeHolder holder=(EyeHolder)row.getTag();

      holder.populateFrom(c, helper);
    }

    @Override
    public View newView(Context ctxt, Cursor c,
                         ViewGroup parent) {
      LayoutInflater inflater=getLayoutInflater();
      View row=inflater.inflate(R.layout.row, parent, false);
      EyeHolder holder=new EyeHolder(row);

      row.setTag(holder);

      return(row);
    }
  }

  static class EyeHolder {
    private TextView disease;

    EyeHolder(View row) {
      disease=(TextView)row.findViewById(R.id.text);
    }

    void populateFrom(Cursor c, EyeHelper helper) {
      disease.setText(helper.getDisease(c));
    }
  }
}

我不知道为什么我的程序在创建时不显示我的数据库，即使我把适配器放到listview

Answer 1

你这样做有点不同我会这么说我很难说什么不对。看起来你的setText调用不正确。您不应该将settext方法放在持有者中。你的绑定应该没问题。我认为您不需要将光标调用它，因为它应该根据适配器中设置的光标自动执行此操作。如果你还没有看到这个链接，它应该有所帮助。 http://www.vogella.de/articles/AndroidListView/article.html#adapterperformance_standard

这对构建自定义适配器有很大帮助。

android没有显示数据库

1 个答案: