Overview
The Shared Object is like a cookie for flash. It lets flash store some data on the local machine, so between sessions it can remember things. Learn more from wikipedia.
Shared Objects are used to store data on the client machine in much the same way that data is stored in a cookie created through a web browser. The data can only be read by movies originating from the same domain that created the Shared Object. This is the only way Macromedia Flash Player can write data to a user’s machine. Shared Objects can not remember a user’s e-mail address or other personal information unless they willingly provide such information.
I’ve seen many Local Shared Object tutorials and examples, which have users input their name and/or hometown and other filler data. But I wanted to show how to creatively incorporate shared objects into interactions. So I’ve thrown in many simultaneous examples including the uber-simple ‘input your name and I’ll remember it’ approach. I hope I didn’t throw in so much that it got confusing… just let me know if you have any questions or anything is unclear. Keeping it simply and broad there’s only a few things to know about Shared Objects.
Steps
- Simply put there are only a couple things to worry about with Local Shared Objects
- Create them.
- As in create the shared object
- Write them.
- As is write to the shared object
- Set them.
- As in setting variables in the shared object
- Get them.
- As in getting variables back out of the shared object
- Clear them.
- As in clearing the shared objec
Actionscript
here’s samples on how to do each of those
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 | /* Create them. */ //make Local Shared Object named myLocalSO(in as) called "myflashcookie" on disk var myLocalSO:SharedObject = SharedObject.getLocal("myflashcookie"); /* Write them. */ //flush the SO, write the SO to disk myLocalSO.flush(); /* Set them. */ //set key's value to specified value in SO //key is the name of the data //val is key's value function setVal(key, val) { myLocalSO.data[key] = val; trace(key +" set to "+val); /* including writing to Shared Object in the setter function */ //flush the SO, write the SO to disk myLocalSO.flush(); } /* Get them. */ //get key's value from SO function getVal(key) { return myLocalSO.data[key]; trace(myLocalSO.data[key] +" received from "+key); } /* Clear them. */ myLocalSO.clear(); |
Example
here’s my colorful example.
The purple/yellow circle is draggable, so place it where you want it. Enter your name and age in the input boxes. Press the center red ‘Set cookie’ button to copy those values to the shared object that is on your computer now. The red transparent circle represents the cookie positions. You can position the purple/yellow circle from the cookie contents with the dark green ‘Position from cookie’ button, or position it randomly with the blue ‘Position randomly’ button. Erase the cookie with the orange ‘Erase cookie’ button. Toggle easing (animation) with the Bright green button (which changes to dark red when off), it tells the current mode of ease. I have the cookie coordinates displayed and the current coordinates of the purple/yellow circle also displayed.
The cookie includes a date object, which is used to calculate the age of the cookie (watch it reset when you erase the cookie (orange button)).
The ‘All Time Visit’ stat is the only thing that does not get reset when you erase the cookie,
and source code:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 | //////////////////////// Initialize variables /////////////////////// //make Local Shared Object named myLocalSO(in as) called "myflashcookie" on disk var myLocalSO:SharedObject = SharedObject.getLocal("myflashcookie"); //speed var for easing var speed = 3; var w = myCircle._width/2; //toggle var for easing var ease = true; //as var to store alltime cookie var allTimeVisitCount=0; countVisit(); cookieFeedback(); //line style for tracing movement lineStyle(1, 0, 50); //////////////////////// Functions /////////////////////// //set key's value to specified value in SO //key is the name of the data //val is key's value function setVal(key, val) { myLocalSO.data[key] = val; trace(key +" set to "+val); //flush the SO, write the SO to disk myLocalSO.flush(); } //get key's value from SO function getVal(key) { return myLocalSO.data[key]; trace(myLocalSO.data[key] +" received from "+key); } function countVisit() { //if first visit if (getVal('visitCount') == undefined) { //create date for now and store in cookie var todayDate:Date = new Date(); setVal('date', todayDate); trace("creating date"); //start/reset counting visits var visitCount = 0; //notice allTimeVisitCount is not reset, but stored still as a var in actionscript } //not first visit else { visitCount = getVal('visitCount'); allTimeVisitCount = getVal('allTimeVisitCount'); } //increment visit counter setVal('visitCount', visitCount+1); setVal('allTimeVisitCount', allTimeVisitCount+1); //feedback of visit counting visitsFeedback.text = getVal('visitCount'); allTimeVisitsFeedback.text = getVal('allTimeVisitCount'); } //feedback of cookie contents function cookieFeedback() { //in defined print coordinate contents cookiex.text = getVal('circleX') == undefined ? "no cookie" : getVal('circleX'); cookiey.text = getVal('circleY') == undefined ? "no cookie" : getVal('circleY'); //if not easing assign coordinates from cookie if (!ease) { myCookie._x = getVal('circleX'); myCookie._y = getVal('circleY'); } //set target to cookie coordinates else { ctargetx = getVal('circleX'); ctargety = getVal('circleY'); } //if name then trace cookie contents if (getVal('name') != undefined) { visitorFeedback.text = "Returning Visitor"; nameInput.text = getVal('name'); ageInput.text = getVal('age'); } //no name then a new visitor else { visitorFeedback.text = "First Time Visitor"; nameInput.text = ""; ageInput.text = ""; } calculateCookieAge(); } function calculateCookieAge() { //make a date now todayDate = new Date(); //get the cookie's stored date cookieDate = getVal('date'); //difference between two dates cookieDateAge = Math.floor(todayDate - cookieDate); //convert miliseconds to a timecode cookieAge.text = msToTimeCode(cookieDateAge);cookieDateAge; } //convert miliseconds to a hh:mm:ss function msToTimeCode(ms) { //make sure value is within bounds. if a number grater than zero and less than the duration of video if (isNaN(ms) || ms< 0) { ms = 0; } //find seconds var sec = ms/1000; //find minutes var min = Math.floor(sec/60); //adjust seconds sec = sec - min*60; //find hours var hour = Math.floor(min/60); //adjust minutes min = min - hour*60; //floor seconds down to whole number sec = Math.floor(sec); //make time code with hours if (hour == 0) { if (sec < 10) { sec = "0"+sec; } if (min < 10) { min = "0"+min; } var tc = min+":"+sec; } //make time code without hours else { if (sec < 10) { sec = "0"+sec; } if (min < 10) { min = "0"+min; } var tc = hour+":"+min+":"+sec; } return tc; } ////// Actionscript attached to Objects/handlers ////////// //place data on stage into cookie (circle coordinates and input text) setCookieButton.onRelease = function() { setVal('circleX', myCircle._x); setVal('circleY', myCircle._y); setVal('name', nameInput.text); setVal('age', ageInput.text); //update the display on stage cookieFeedback(); } //make random coordinates on stage randomButton.onRelease = function() { //if not easing assign coordinates to myCircle if (!ease) { myCircle._x = Math.random() * (Stage.width - w); myCircle._y = Math.random() * (Stage.height - w); } //if easing assign coordinates to myCircle's target coords else { targetx = Math.random() * (Stage.width - w); targety = Math.random() * (Stage.height - w); } } myCircle.onPress = function() { this.startDrag(); dragging = true; lineStyle(1, 200, 30); } myCircle.onRelease = myCircle.onReleaseOutside = function() { targetx = this._x; targety = this._y; lineStyle(1, 0, 50); dragging = false; this.stopDrag(); } myCircle.onEnterFrame = function() { //print position feedback currentx.text = this._x; currenty.text = this._y; //if eas move to target if (ease) { if (!dragging) { moveTo(this._x+w, this._y+w); this._x+=(targetx-this._x)/speed; this._y+=(targety-this._y)/speed; } //draw line lineTo(this._x+w, this._y+w); } } myCookie.onEnterFrame = function() { //if ease move cookie to target if (ease) { this._x+=(ctargetx-this._x)/speed; this._y+=(ctargety-this._y)/speed; } calculateCookieAge(); } //Position from Cookie cookieButton.onRelease = function() { //if not easing set coordinates from cookie if (!ease) { myCircle._x = getVal('circleX'); myCircle._y = getVal('circleY'); } //if easing set target coordinates from cookie else { targetx = getVal('circleX'); targety = getVal('circleY'); } } easeBtn.onRelease = function () { //toggle easing ease = !ease; //advance the frame of this button... this.play(); } clearCookieBtn.onRelease = function() { //clear the cookie (swipe all data) myLocalSO.clear(); //restart visit count countVisit(); //read cookie and give feedback cookieFeedback(); } |
Source
download the source for this example: sharedObject.fla
