Question

我在android stodio中创建了名为stats.csv的CSV文件，因此我创建了3个类：

第一

import android.app.Activity;
import android.os.Bundle;
import android.os.Parcelable;
import android.widget.ListView;

import java.io.InputStream;
import java.util.List;


public class MyDatabase extends Activity {

    private ListView listView;
    private ItemArrayAdapter itemArrayAdapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_my_database);

        listView = (ListView) findViewById(R.id.list_view);
        itemArrayAdapter = new ItemArrayAdapter(getApplicationContext(), R.layout.single_list_item);

        Parcelable state = listView.onSaveInstanceState();
        listView.setAdapter(itemArrayAdapter);
        listView.onRestoreInstanceState(state);

        InputStream inputStream = getResources().openRawResource(R.raw.stats);
        CSVReader csv = new CSVReader(inputStream);
        List<String[]> scoreList = csv.read();

        for(String [] scoreData : scoreList)
        {
            itemArrayAdapter.add(scoreData);
        }

    }

}

第二

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.TextView;

import java.util.ArrayList;
import java.util.List;


public class ItemArrayAdapter extends ArrayAdapter<String[]>{

    private List<String[]> scoreList = new ArrayList<String[]>();

    static class ItemViewHolder {
        TextView namee;
        TextView score;
    }

    public ItemArrayAdapter(Context context, int resource) {
        super(context, resource);
    }

    public void add(String[] object) {
        scoreList.add(object);
        super.add(object);
    }

    @Override
    public int getCount() {
        return this.scoreList.size();
    }

    @Override
    public String[] getItem(int position) {
        return this.scoreList.get(position);
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        View row = convertView;
        ItemViewHolder viewHolder;
        if(row == null) {
            LayoutInflater inflater = (LayoutInflater) this.getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            row = inflater.inflate(R.layout.single_list_item, parent, false);
            viewHolder = new ItemViewHolder();
            viewHolder.namee = (TextView) row.findViewById(R.id.namee);
            viewHolder.score = (TextView) row.findViewById(R.id.score);
            row.setTag(viewHolder);
        } else {
            viewHolder = (ItemViewHolder) row.getTag();
        }

        String[] stat = getItem(position);
        viewHolder.namee.setText(stat[0]);
        viewHolder.score.setText(stat[1]);
        return row;

    }
}

第三

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.List;


public class CSVReader {
    InputStream inputStream;
    
    public CSVReader (InputStream is) 
    {
        this.inputStream = is;
    }
    
    public List<String[]> read () {
        List<String[]> resultList = new ArrayList<String[]>();
        BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream));
        
        try {
            String csvLine;
            while((csvLine = reader.readLine()) != null) {
                String[] row = csvLine.split(",");
                resultList.add(row);
            }
        } catch (IOException ex) {
            throw new RuntimeException("Error iv reading CSV file:" + ex);
        }
        finally {
            try {
                inputStream.close();
            } catch (IOException e) {
                throw new RuntimeException("Error while closing input strem:" + e);
            }
        }
        return resultList;
    }
}

^这些代码显示了我的csv文件的列表视图。但是当我尝试插入SQLite时它不起作用。这里我正在尝试第三课：

import android.content.ContentValues;
import android.database.sqlite.SQLiteDatabase;
import android.util.Log;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.List;

public class CSVReader {
    InputStream inputStream;

    public CSVReader (InputStream is)
    {
        this.inputStream = is;
    }

    public List<String[]> read () {
        List<String[]> resultList = new ArrayList<String[]>();
        BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream));
 
        SQLiteDatabase db =this.getWritableDatabase(); /* THE ERROR SHOWN HERE : " " */

        String csvLine = "";
        db.beginTransaction();
        try {
            while((csvLine = reader.readLine()) != null) {
                String[] row = csvLine.split(",");
                if (row.length != 2) {
                    Log.d("CSVParser", "Skipping Bad CSV Row");
                    continue;
                }
                ContentValues cv = new ContentValues(2);
                cv.put("namee", row[0].trim());
                cv.put("score", row[1].trim());
                db.insert("TABLE", null, cv);
                resultList.add(row);
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
        db.setTransactionSuccessful();
        db.endTransaction();

        return resultList;
    }
}

错误消息：" Error:(26, 32) error: cannot find symbol method getWritableDatabase() , "

你可以帮我吗？

Answer 1

public class YourDatabaseName extends SQLiteOpenHelper {
private static final String LOGCAT = null;

public YourDatabaseName(Context applicationcontext) {
    super(applicationcontext, "androidsqlite.db", null, 12);
    Log.d(LOGCAT, "Created the Database");
}

@Override
public void onCreate(SQLiteDatabase database) {
    String query1;
    query1 = "CREATE TABLE SomeTableName"
            + "(_id INTEGER PRIMARY KEY, " + // 1
            "names TEXT, " +  //2
            "scores TEXT)"; //3 This should probably be a float
            database.execSQL(query1);
    Log.d(LOGCAT, "SomeTableName Created");
}

@Override
public void onUpgrade(SQLiteDatabase database, int oldVersion,
        int newVersion) {
    String query1;
    query1 = "DROP TABLE IF EXISTS SomeTableName";
    database.execSQL(query1);
    onCreate(database);

}

public void insertdata(HashMap<String, String> inserting) {
    Log.d(LOGCAT, "SomeTableName inserted");
    SQLiteDatabase database = this.getWritableDatabase();
    ContentValues values = new ContentValues();
    values.put("names", inserting.get("names"));
    values.put("scores", inserting.get("score"));
    database.insert("SomeTableName", null, values);
    database.close();

    } }

然后在您的活动中

YourDateBaseName controller = new YourDateBaseName(this);//or (YourActivity.this)
Context context = this;

HashMap<String, String> datavalues = new HashMap<String, String>();
datavalues.put("names", names);
datavalues.put("scores", scores);
controller.insertdata(datavalues);

如何在android上将CSV文件插入SQLite数据库？

1 个答案: