Qt Reference Documentation

Storage.js Example File

demos/symbian/musicplayer/qml/Storage.js
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 function openDatabase() {
     return openDatabaseSync("musicplayer", "1.0", "Settings", 100000)
 }

 function initialize() {
     var db = openDatabase()
     db.transaction(
         function(tx) {
             tx.executeSql("CREATE TABLE IF NOT EXISTS settings(setting TEXT UNIQUE, value TEXT)")
             tx.executeSql("CREATE TABLE IF NOT EXISTS playlist(source TEXT, title TEXT, artist TEXT, time TEXT)")
         }
     )
 }

 function setSetting(setting, value) {
     var db = openDatabase()
     var res = "Error"
     db.transaction(
         function(tx) {
             var rs = tx.executeSql("INSERT OR REPLACE INTO settings VALUES (?,?);", [setting,value])
             if (rs.rowsAffected > 0)
                 res = "OK"
         }
     )
     return res
 }

 function getSetting(setting) {
     var db = openDatabase()
     var res = "Unknown"
     db.transaction(
         function(tx) {
             var rs = tx.executeSql("SELECT value FROM settings WHERE setting=?;", [setting])
             if (rs.rows.length > 0)
                 res = rs.rows.item(0).value
         }
     )
     return res
 }

 function getPlaylist(playlist) {
     var db = openDatabase()
     var res = "Unknown"
     db.transaction(
         function(tx) {
             var rs = tx.executeSql("SELECT * FROM playlist;")
             if (rs.rows.length > 0) {
                 for (var i = 0; i < rs.rows.length; i++) {
                     playlist.append({"source": rs.rows.item(i).source,
                                     "title": rs.rows.item(i).title,
                                     "artist": rs.rows.item(i).artist,
                                     "time": rs.rows.item(i).time,
                                     "selected": false})
                 }
                 res = "OK"
             }
         }
     )
     return res
 }

 function setPlaylist(playlist) {
     var db = openDatabase()
     var res = "Error"
     db.transaction(
         function(tx) {
             var rs = tx.executeSql("DELETE FROM playlist;")
             var count = 0
             for (var i = 0; i < playlist.count; i++) {
                 rs = tx.executeSql("INSERT INTO playlist VALUES (?,?,?,?);",
                     [playlist.get(i).source, playlist.get(i).title, playlist.get(i).artist, playlist.get(i).time])
                 count += rs.rowsAffected
             }

             if (count > 0)
                 res = "OK"
         }
     )
     return res
 }