[移动开发]基于Android studio下的Notepad日志本（二）java代码实现

数据库功能实现

NotesDB（全）?

package com.dj.notepad;

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

public class NotesDB extends SQLiteOpenHelper {

    public static final String TABLE_NAME = "notes";
    public static final String CONTENT = "content";
    public static final String PATH = "path";
    public static final String VIDEO = "video";
    public static final String ID = "_id";
    public static final String TIME = "time";

    public NotesDB(Context context) {
        super(context, "notes", null, 1);
    }
    @Override
    public void onCreate(SQLiteDatabase db) {
        db.execSQL("CREATE TABLE " + TABLE_NAME + " (" + ID
                + " INTEGER PRIMARY KEY AUTOINCREMENT," + CONTENT
                + " TEXT NOT NULL," + PATH + " TEXT NOT NULL," + VIDEO
                + " TEXT NOT NULL," + TIME + " TEXT NOT NULL)");
    }
    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {}
}

自定义功能实现

Myadapter（全）

package com.dj.notepad;

import android.content.Context;
import android.database.Cursor;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.media.ThumbnailUtils;
import android.provider.MediaStore;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.TextView;

public class MyAdapter extends BaseAdapter {

    private Context context;
    private Cursor cursor;
    private LinearLayout layout;

    public MyAdapter(Context context, Cursor cursor) {
        this.context = context;
        this.cursor = cursor;
    }

    @Override
    public int getCount() {
        return cursor.getCount();
    }

    @Override
    public Object getItem(int position) {
        return cursor.getPosition();
    }

    @Override
    public long getItemId(int position) {
        // TODO Auto-generated method stub
        return position;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        LayoutInflater inflater = LayoutInflater.from(context);
        layout = (LinearLayout) inflater.inflate(R.layout.cell, null);
        //控件按钮
        TextView contenttv = (TextView) layout.findViewById(R.id.list_content);
        TextView timetv = (TextView) layout.findViewById(R.id.list_time);
        ImageView imgiv = (ImageView) layout.findViewById(R.id.list_img);
        ImageView videoiv = (ImageView) layout.findViewById(R.id.list_video);

        cursor.moveToPosition(position);

        String content = cursor.getString(cursor.getColumnIndexOrThrow("content"));
        String time = cursor.getString(cursor.getColumnIndexOrThrow("time"));
        String url = cursor.getString(cursor.getColumnIndexOrThrow("path"));
        String urlvideo = cursor.getString(cursor.getColumnIndexOrThrow("video"));
        //set功能
        contenttv.setText(content);
        timetv.setText(time);
        imgiv.setImageBitmap(getImageThumbnail(url, 100, 100));
        videoiv.setImageBitmap(getVideoThumbnail(urlvideo, 100, 100,
                MediaStore.Images.Thumbnails.MICRO_KIND));
        return layout;
    }
    /** ListView 显示图片*/
    public Bitmap getImageThumbnail(String uri, int width, int height) {
        Bitmap bitmap = null;
        BitmapFactory.Options options = new BitmapFactory.Options();
        //options.inJustDecodeBounds = true;
        //bitmap = BitmapFactory.decodeFile(uri, options);
        options.inJustDecodeBounds = false;
        int beWidth = options.outWidth / width;
        int beHeight = options.outHeight / height;
        int be = 1;
        if (beWidth < beHeight) {
            be = beWidth;
        } else {
            be = beHeight;
        }
        if (be <= 0) {
            be = 1;
        }
        options.inSampleSize = be;
        bitmap = BitmapFactory.decodeFile(uri, options);
        bitmap = ThumbnailUtils.extractThumbnail(bitmap, width, height,
                ThumbnailUtils.OPTIONS_RECYCLE_INPUT);
        return bitmap;
    }
    /**视频缩略图*/
    private Bitmap getVideoThumbnail(String uri, int width, int height, int kind) {
        Bitmap bitmap = null;
        bitmap = ThumbnailUtils.createVideoThumbnail(uri, kind);
        bitmap = ThumbnailUtils.extractThumbnail(bitmap, width, height,
                ThumbnailUtils.OPTIONS_RECYCLE_INPUT);
        return bitmap;
    }
}

添加信息功能实现

AddContent（全）

先不整了，等我12月27号考完试之后我再把剩下的代码一次性分享上来吧，有缘人耐心等待。