Question

晚上好，有点堆叠溢出的人。我希望将所有数据从我的数据库中拉出来并在TextView中显示它。我怎样才能做到这一点？

此外，我想从数据库中提取数据（全部）并通过soap消息将其发送到远处的WS。我对WSDL设置没有任何疑问，但我确实需要有关如何从数据库中提取数据并一次又一次地使用它的信息。

以下是代码：

package com.example.prototype2;



import android.os.Bundle;
import android.app.Activity;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.support.v4.app.NavUtils;

public class AddGlucose extends Activity implements OnClickListener {

final String LOG_TAG = "myLogs";

Button btnAdd, btnRead, btnClear;
  EditText etGlucose, etTime, etDate;

  DBHelper dbHelper;

 @Override
 protected void onCreate(Bundle savedInstanceState) {
 super.onCreate(savedInstanceState);
 setContentView(R.layout.activity_add_glucose);
 // Show the Up button in the action bar.
 setupActionBar();

 btnAdd = (Button) findViewById(R.id.btnAdd);
 btnAdd.setOnClickListener(this);

 btnRead = (Button) findViewById(R.id.btnRead);
 btnRead.setOnClickListener(this);

 btnClear = (Button) findViewById(R.id.btnClear);
 btnClear.setOnClickListener(this);

 etGlucose = (EditText) findViewById(R.id.etGlucose);
 etTime = (EditText) findViewById(R.id.etTime);
 etDate = (EditText) findViewById(R.id.etDate);
 dbHelper = new DBHelper(this);
}

/**
* Set up the {@link android.app.ActionBar}.
*/
private void setupActionBar() {

getActionBar().setDisplayHomeAsUpEnabled(true);

}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.add_glucose, menu);
return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case android.R.id.home:
    // This ID represents the Home or Up button. In the case of this
    // activity, the Up button is shown. Use NavUtils to allow users
    // to navigate up one level in the application structure. For
    // more details, see the Navigation pattern on Android Design:
    //
    // http://developer.android.com/design/patterns/navigation.html#up-vs-back
    //
    NavUtils.navigateUpFromSameTask(this);
    return true;
}
return super.onOptionsItemSelected(item);
}

@Override
public void onClick(View v) {
// TODO Auto-generated method stub
ContentValues cv = new ContentValues();
String glucose = etGlucose.getText().toString();
String time = etTime.getText().toString();
String date = etDate.getText().toString();

SQLiteDatabase db = dbHelper.getWritableDatabase();

switch (v.getId()) {
case R.id.btnAdd:
  Log.d(LOG_TAG, "--- Insert in mytable: ---");

  cv.put("glucose", glucose);
  cv.put("time", time);
  cv.put("date", date);
long rowID = db.insert("mytable", null, cv);
  Log.d(LOG_TAG, "row inserted, ID = " + rowID);
  break;

case R.id.btnRead:
    Log.d(LOG_TAG, "--- Rows in mytable: ---");
    Cursor c = db.query("mytable", null, null, null, null, null, null, null);
    if (c.moveToFirst()) {
        int idColIndex = c.getColumnIndex("id");
        int glucoseColIndex = c.getColumnIndex("glucose");
        int timeColIndex = c.getColumnIndex("time");
        int dateColIndex = c.getColumnIndex("date");

        do {    

            Log.d(LOG_TAG,
                    "ID = " + c.getInt(idColIndex) + 
                    ", glucose = " + c.getString(glucoseColIndex) +
                    ", time = " + c.getString(timeColIndex) + ", date = " +       c.getString(dateColIndex));
        } while (c.moveToNext());
    } else
        Log.d(LOG_TAG, "0 rows");
    c.close();
    break;

 case R.id.btnClear:
  Log.d(LOG_TAG, "--- Clear mytable: ---");

  int clearCount = db.delete("mytable", null, null);
  Log.d(LOG_TAG, "deleted rows count = " + clearCount);
  break;
}
dbHelper.close();
}

class DBHelper extends SQLiteOpenHelper {

    public DBHelper(Context context) {

      super(context, "mytable", null, 1);
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
      Log.d(LOG_TAG, "--- onCreate database ---");
      // создаем таблицу с полями
      db.execSQL("create table mytable ("
          + "id integer primary key autoincrement," 
          + "glucose text,"
          + "time text," + "date text" + ");");
    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {

    }
  }

 }

Answer 1

以下是一个非常好的SQLite示例代码的链接：http://www.androidhive.info/2011/11/android-sqlite-database-tutorial/

因此，您只需要自定义数据库的代码，但我想告诉您，如果为行元素创建自定义对象（如示例代码），则更容易，更舒适。

Answer 2

您刚刚在一个类中插入了如此多的代码，似乎没有红线。请遵循以下教程，并根据您的需要更改解释的代码。一切都很完美，您将在设置完成后如何从数据库中获取信息。

数据库是如此重要，你应该占用它一点点。

Tut 1

从SQLite数据库中提取数据并在Textview中显示它

2 个答案: