0

好的，我是整个 android 平台的新手，我正在尝试将我需要的所有信息基本上放入数据库表中，然后将信息拉入我的活动中，基本上就像....每一行代表一个项目（让我们说是 100 个）然后有一列用于描述、食物、位置、名称，如果可能的话，还有图像。目前我只是手动将所有信息添加到单独的 xml 布局中，这似乎比我可以从数据库中提取信息要耗时和困难得多，对吧？

我目前在做什么：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="@color/white"
android:orientation="vertical" >

<TextView
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="@color/white"
    android:gravity="center"
    android:text="@string/bluefish"
    android:textColor="@color/black"
    android:textSize="30dp"
    android:textStyle="bold" />

<ImageView
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:contentDescription="@string/bluefish"
    android:src="@drawable/bluefish" />

<TextView
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="@color/white"
    android:gravity="left"
    android:text="@string/desc"
    android:textColor="@color/black"
    android:textSize="14dp"
    android:textStyle="bold" />

<TextView
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="@color/white"
    android:gravity="left"
    android:text="text here"
    android:textColor="@color/black"
    android:textSize="12dp" />

<TextView
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="@color/white"
    android:gravity="left"
    android:text="@string/food"
    android:textColor="@color/black"
    android:textSize="14dp"
    android:textStyle="bold" />

<TextView
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="@color/white"
    android:gravity="left"
    android:text="text here"
    android:textColor="@color/black"
    android:textSize="12dp" />

<TextView
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="@color/white"
    android:gravity="left"
    android:text="@string/loc"
    android:textColor="@color/black"
    android:textSize="14dp"
    android:textStyle="bold" />

<TextView
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="@color/white"
    android:gravity="left"
    android:text="text here"
    android:textColor="@color/black"
    android:textSize="12dp" />

4

1 回答 1

0

使用以下代码创建 Db 这将创建新的 DB SaveImage

import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.widget.Toast;

public class DbHelper extends SQLiteOpenHelper {

    public static final int DB_VERSION = 1;
    public static final String DB_NAME = "SaveImage";

public DbHelper(Context context) {
    super(context, DB_NAME, null, DB_VERSION);
    // TODO Auto-generated constructor stub
}

@Override
public void onCreate(SQLiteDatabase db) {
    // TODO Auto-generated method stub

    String tblSaveImage =  "CREATE  TABLE tblSaveImage (_id INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL , Image BLOB);";

    db.execSQL(tblSaveImage);
}

@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
    // TODO Auto-generated method stub

}
}

将图像保存到数据库中：

如果您不想使用 SQL 查询，您还可以使用内容值将数据插入数据库。

import java.io.ByteArrayOutputStream;

import android.app.Activity;
import android.content.ContentValues;
import android.content.Intent;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.graphics.Bitmap;
import android.net.Uri;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.TextView;


public class SaveImage extends Activity {

SQLiteDatabase Db;

TextView txt;
Button btnImage,btnSaveimage;
ImageView imageView;

byte[] byteArray;

private static final int PICK_FROM_FILE = 2;
private Uri mImageCaptureUri;

/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    Initialize();


    //btnSaveImage Handler Save Byte Array to DB and Navigate to ShowImage Activity

    btnSaveimage.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub
            try {
                ContentValues cv = new ContentValues();
                cv.put("Image", byteArray);
                Db.insert("tblSaveImage", null, cv);

                startActivity(new Intent(getApplicationContext(),ShowImage.class));
            } catch (Exception e) {
                // TODO: handle exception
                txt.setText(e.toString());
            }
        }
    });


    //btnImage Handler Access to Gallery of Device and Display all Images save in Device.

    btnImage.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub
            Intent intent = new Intent();

               intent.setType("image/*");
               intent.setAction(Intent.ACTION_GET_CONTENT);

               startActivityForResult(Intent.createChooser(intent, "Complete action using"), PICK_FROM_FILE);
        }
    });

}

// To Initialize all the Components.

private void Initialize() {
    // TODO Auto-generated method stub
    txt = (TextView)findViewById(R.id.txt);
    btnImage = (Button)findViewById(R.id.btnImage);
    imageView = (ImageView)findViewById(R.id.imageView);
    btnSaveimage = (Button)findViewById(R.id.btnSaveImage);

    DbHelper h = new DbHelper(this);
    try {
        Db = h.getWritableDatabase();   
    } catch (SQLException e) {
        // TODO: handle exception
        Db = h.getReadableDatabase();
    }

}


// OnActivityResult PICK_IMAGE_FROM_FILE
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    // TODO Auto-generated method stub

    mImageCaptureUri = data.getData();
    imageView.setImageURI(mImageCaptureUri);
    imageView.buildDrawingCache();
    Bitmap bmp = imageView.getDrawingCache();

    ByteArrayOutputStream stream = new ByteArrayOutputStream();
    bmp.compress(Bitmap.CompressFormat.PNG, 100, stream);
    byteArray = stream.toByteArray();
    super.onActivityResult(requestCode, resultCode, data);
}
}

显示保存在 DB 中的图像：

import android.app.Activity;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.Bundle;
import android.widget.ImageView;

public class ShowImage extends Activity {

ImageView showImage;

SQLiteDatabase Db;
Cursor result;

@Override
protected void onCreate(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onCreate(savedInstanceState);
    setContentView(R.layout.display);

    showImage = (ImageView)findViewById(R.id.showImage);

   DbHelper h = new DbHelper(this);

   try {
    Db = h.getWritableDatabase();
} catch (SQLException e) {
    // TODO: handle exception
    Db = h.getReadableDatabase();
}

result = Db.rawQuery("Select Image from tblSaveImage", null);

if (result.moveToLast()) {

    byte[] byteArray = result.getBlob(0);
    Bitmap bmp = BitmapFactory.decodeByteArray(byteArray, 0, byteArray.length);

    showImage.setImageBitmap(bmp);
}


}

}
于 2012-04-30T06:23:27.943 回答