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  • android中SQLite实现

    SQLite操作类:

    package com.example.administrator.myapplication;
    
    import android.content.Context;
    import android.database.sqlite.SQLiteDatabase;
    import android.database.sqlite.SQLiteOpenHelper;
    
    public class BookmarkSQLiteOpenHelper extends SQLiteOpenHelper{
        public BookmarkSQLiteOpenHelper(Context context, String name, SQLiteDatabase.CursorFactory factory, int version){
            super(context,name,factory,version);
        }
    
        @Override
        public void onCreate(SQLiteDatabase db){
            String sql="create table bookmark(id integer primary key autoincrement,favicon varchar(100),title varchar(100),url varchar(100))";
            db.execSQL(sql);
        }
    
        @Override
        public void onUpgrade(SQLiteDatabase db,int oldVersion,int newVersion){}
    }

    SQLite初始化:

    bookmarkSQLiteOpenHelper=new BookmarkSQLiteOpenHelper(this,"browser.db",null,1);

    SQLite插入数据:

    void insertBookmark(Bookmark bookmark){
            SQLiteDatabase db=bookmarkSQLiteOpenHelper.getWritableDatabase();
            db.execSQL("insert into bookmark(favicon,title,url)values(?,?,?)",new String[]{bookmark.getFavicon(),bookmark.getTitle(),bookmark.getUrl()});
        }

     SQLite查询数据:

    bookmarkSQLiteOpenHelper=new BookmarkSQLiteOpenHelper(this,"browser.db",null,1);
            SQLiteDatabase db=bookmarkSQLiteOpenHelper.getReadableDatabase();
            Cursor cursor=db.rawQuery("select * from bookmark",null);
            while(cursor.moveToNext()){
                String favicon=cursor.getString(cursor.getColumnIndex("favicon"));
                String title=cursor.getString(cursor.getColumnIndex("title"));
                String url=cursor.getString(cursor.getColumnIndex("url"));
    
                Bitmap bitmap=null;
                try{
                    String sdcard_path=Environment.getExternalStorageDirectory().getCanonicalPath();
                    String bitmap_path=sdcard_path+"/xinyuelantuBrowserFavicon/"+favicon+".jpg";
                    bitmap=BitmapFactory.decodeFile(bitmap_path);
                }
                catch(IOException e){}
                Map<String,Object> map_bookmark=new HashMap<String,Object>();
                map_bookmark.put("favicon",bitmap);
                map_bookmark.put("title",title);
                map_bookmark.put("url",url);
                arraylist_bookmark.add(map_bookmark);
            }
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  • 原文地址:https://www.cnblogs.com/zqxLonely/p/5462549.html
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