Question

我目前在存储和检索数据库中的图像时遇到问题。全部设置但程序停止，同时单击按钮保存并从数据库中获取图片。该错误在我的Log cat中显示为“无法执行活动方法”。

请帮帮我！以下是代码。

DATABASEHELPER.java

Fabric.with(this, new Crashlytics.Builder().core(
    new CrashlyticsCore.Builder().disabled(BuildConfig.DEBUG).build()).build());

MainActivity.java

package com.example.image_database;

import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteDatabase.CursorFactory;
import android.database.sqlite.SQLiteOpenHelper;
import android.os.Bundle;
import android.widget.ImageView;


class DatabaseHelper extends SQLiteOpenHelper {



private final static String DATABASE_NAME = "test.db";
private static final int DATABASE_VERSION = 1;



            DatabaseHelper(Context context) {

                super(context, DATABASE_NAME, null, DATABASE_VERSION);

            }



@Override
            public void onCreate(SQLiteDatabase db) {
    db.execSQL("Create table if not exists tb(a blob)");


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


}


}

activity_main.xml中

package com.example.image_database;

import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;

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.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.Toast;

public class MainActivity extends Activity {

    ImageView image1;
    SQLiteDatabase db;
    Button btn1,btn2;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        image1 = (ImageView) this.findViewById(R.id.image1);
        btn1 = (Button) this.findViewById(R.id.save);
        btn2 = (Button) this.findViewById(R.id.get);


        }




    public void saveImage(View v)
     {
         try {
            FileInputStream fis = new FileInputStream("/storage/sdcard/4.jpg");
            try {
                byte[] image = new byte[fis.available()];
                fis.read(image);

                ContentValues values = new ContentValues();
                values.put("a", image);

                db.insert("tb", null, values);

                fis.close();




            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        } catch (FileNotFoundException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
     }



    public void getImage(View v)
    {
        Cursor c = db.rawQuery("Select * from tb", null);
        if(c.moveToNext())
        {
            byte[] image = c.getBlob(0);
            Bitmap bmp = BitmapFactory.decodeByteArray(image, 0,image.length);
            image1.setImageBitmap(bmp);

        }

    }


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

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();
        if (id == R.id.action_settings) {
            return true;
        }
        return super.onOptionsItemSelected(item);
    }
    }

Answer 1

在Android sqlite db上存储数据库中的图像并不酷？您应该将图像存储在文件夹中。

在sqlite数据库中存储图像时出错

1 个答案: