How to implement auto-hide navigation? - web

I'm not sure where to post this question, so please excuse me if I am violating any policies.
To clarify my question, I want to achieve the same navigation bar as Teehan + Lax's.
Here is their website: http://www.teehanlax.com/tools/
If you notice, the navigation auto hides itself when you scroll down, however when you scroll up it would show it self again.
So my question is, how did they achieve this? Is it through only CSS or do I need JavaScript to do this? Whatever way it is, can someone also point towards the right direction on how I can find the information to implement this?
Thank you

It's not possible to change position from fixed to absolute in pure CSS like you want, so I used some javascript to do so. Demo
function followTo(elem, pos) {
var element = document.getElementById(elem);
window.onscroll = function(e){
var disFromTop = document.all? iebody.scrollTop : pageYOffset;
if (disFromTop > pos) {
element.style.position = 'absolute';
element.style.top = pos + 'px';
} else {
element.style.position = 'fixed';
element.style.top = 0;
}
};
};
followTo("nav", 100);
It even includes an IE fix pulled from this SO post to get the correct scroll position
Here is the jQuery version, taken from this SO post
EDIT
As pointed out by zanona, I did not include the feature where the navigation appears if you scroll up from a place further down in the page. As a result, I create a new technique that uses a setInterval
var last = 0, // The last read top value
delay = 150, // The delay for the setInterval
threshold = 30; // The max scroll distance before showing/hiding the nav
//I always set a variable to my setIntervals in case I want to stop them later on
var navMovement = setInterval(function() {
var nav = document.getElementById('nav'), // Gets nav object
pageVertOffset = document.all? iebody.scrollTop : pageYOffset;
// Happens if the difference in scroll is below the negative threshold
if(pageVertOffset - last < -threshold) {
nav.style.top = "0px"; // Put the nav at the top of the window
}
// Happens if the difference in scroll is above the threshold
else if(pageVertOffset - last > threshold){
nav.style.top = - nav.offsetHeight + "px"; // Hides the navigation
}
last = pageVertOffset; // Updates the previous scroll value
}, delay); // Runs every `delay` amount
Javascript version, or if you prefer, jQuery version
I thought I recreated the site pretty well (but it's better because mine has a kitten, haha)

Related

Moving objects collision Phaser [closed]

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My collision of moving objects is not working. I have created a demo so you can see it and see my problem all code and everything included.
As you may be able to see, I have 2 blocks coming from left to right and then I have a tank shooting bullets> I tried in all kind of directions and I always get the same results, basically my collision only works the velocity of the blocks value, in the example on the zip file only works up to 300px. Depending on the blocks speed, if I change the block speed to a greater number then the collision works on the same numbers pixels. it is really weird.
I was wondering if I'm just doing the whole thing wrong or what could my problem be? I would appreciate any pointers or ideas that can help me solve this issue. Thanks.
Demo source code.
BasicGame.Game = function (game) {
// When a State is added to Phaser it automatically has the following properties set on it, even if they already exist:
this.game; // a reference to the currently running game (Phaser.Game)
this.add; // used to add sprites, text, groups, etc (Phaser.GameObjectFactory)
this.camera; // a reference to the game camera (Phaser.Camera)
this.cache; // the game cache (Phaser.Cache)
this.input; // the global input manager. You can access this.input.keyboard, this.input.mouse, as well from it. (Phaser.Input)
this.load; // for preloading assets (Phaser.Loader)
this.math; // lots of useful common math operations (Phaser.Math)
this.sound; // the sound manager - add a sound, play one, set-up markers, etc (Phaser.SoundManager)
this.stage; // the game stage (Phaser.Stage)
this.time; // the clock (Phaser.Time)
this.tweens; // the tween manager (Phaser.TweenManager)
this.state; // the state manager (Phaser.StateManager)
this.world; // the game world (Phaser.World)
this.particles; // the particle manager (Phaser.Particles)
this.physics; // the physics manager (Phaser.Physics)
this.rnd; // the repeatable random number generator (Phaser.RandomDataGenerator)
// You can use any of these from any function within this State.
// But do consider them as being 'reserved words', i.e. don't create a property for your own game called "world" or you'll over-write the world reference.
this.bulletTimer = 0;
};
BasicGame.Game.prototype = {
create: function () {
//Enable physics
// Set the physics system
this.game.physics.startSystem(Phaser.Physics.ARCADE);
//End of physics
// Honestly, just about anything could go here. It's YOUR game after all. Eat your heart out!
this.createBullets();
this.createTanque();
this.timerBloques = this.time.events.loop(1500, this.createOnebloque, this);
},
update: function () {
if(this.game.input.activePointer.isDown){
this.fireBullet();
}
this.game.physics.arcade.overlap(this.bullets, this.bloque, this.collisionBulletBloque, null, this);
},
createBullets: function() {
this.bullets = this.game.add.group();
this.bullets.enableBody = true;
this.bullets.physicsBodyType = Phaser.Physics.ARCADE;
this.bullets.createMultiple(100, 'bulletSprite');
this.bullets.setAll('anchor.x', 0.5);
this.bullets.setAll('anchor.y', 1);
this.bullets.setAll('outOfBoundsKill', true);
this.bullets.setAll('checkWorldBounds', true);
},
fireBullet: function(){
if (this.bulletTimer < this.game.time.time) {
this.bulletTimer = this.game.time.time + 1400;
this.bullet = this.bullets.getFirstExists(false);
if (this.bullet) {
this.bullet.reset(this.tanque.x, this.tanque.y - 20);
this.game.physics.arcade.enable(this.bullet);
this.bullet.enableBody = true;
this.bullet.body.velocity.y = -800;
}
}
},
createOnebloque: function(){
this.bloquecs = ["bloqueSprite","bloquelSprite"];
this.bloquesr = this.bloquecs[Math.floor(Math.random()*2)];
this.bloque = this.add.sprite(0, 360, this.bloquesr);
this.game.physics.arcade.enable(this.bloque);
this.bloque.enableBody = true;
this.bloque.body.velocity.x = 300;
this.bloque.body.kinematic = true;
this.bloque.checkWorldBounds = true;
this.bloque.outOfBoundsKill = true;
this.bloque.body.immovable = true;
},
createTanque: function() {
this.tanqueBounds = new Phaser.Rectangle(0, 600, 1024, 150);
this.tanque = this.add.sprite(500, 700, 'tanqueSprite');
this.tanque.inputEnabled = true;
this.tanque.input.enableDrag(true);
this.tanque.anchor.setTo(0.5,0.5);
this.tanque.input.boundsRect = this.tanqueBounds;
},
collisionBulletBloque: function(bullet, bloque) {
this.bullet.kill();
},
quitGame: function (pointer) {
// Here you should destroy anything you no longer need.
// Stop music, delete sprites, purge caches, free resources, all that good stuff.
// Then let's go back to the main menu.
this.state.start('MainMenu');
}
};
The code definitely helps, but you can actually get an idea of what's happening just from playing the game.
As the blocks are going by you can actually get the bullets to disappear if you fire and hit the right edge of the center-most block.
What's happening is that you're checking for a collision between the bullets and a block, but the block is getting redefined every time you add a new one to the screen on the left.
What you probably want to do is create a pool of blocks (bloquePool for example), almost exactly like what you're doing in createBullets with your bullet pool (what you've called bullets).
Then check for a collision between the group of bullets and the group of blocks.
this.game.physics.arcade.overlap(
this.bullets, this.bloquePool, this.collisionBulletBloque, null, this
);
You should get the individual bullet and the individual block that collided passed into collisionBulletBloque so you can still kill the bullet as you are.

Multithreading in flex web application

I am working on web application. In which i am stuck with some issue.
When i call some server function it will take time to get response. When response have high number of data. It will get data, process on that data and update GUI in background.
Upto that my application GUI freeze. I can not click on any part. I see some where that ActionScript support multithreading. I found some tutorial for that which is here. But, it is for desktop application only.
Is there any way i can handle this freezing of application/GUI in web application. It will decrease my application performance and looks very bad.
Example:
If i have list of data with checkbox and on checkbox click there is some process. Now, there is one button called "Select All". Now, if i click on "select all" then all check box selected and process on check selection is going and freeze the application upto process done.
like: I have following list
<s:List id="tempList" itemRenderer="CustomItemRenderer"
dataProvider="{someList}" useVirtualLayout="false"/>
ItemRenderer have label and checkbox as following.
<s:CheckBox id="cCheckId" selected="{data.selected}"
change="onChangeHandler(event)" />
<s:Label id="lblTest" />
protected function onChangeHandler(event:Event):void
{
data.selected = !data.selected;
}
Now, on button Select all will select all check box.
<s:Button id="btnSelectAll" label="Select All" click="selectAllHandler(event)" />
protected function selectAllHandler(event:MouseEvent):void
{
for(var i:int = 0;i<someList.length;i++)
{
someList[i].selected = true;
}
}
Now, if someList have lots of data then it will freeze the screen.
Any help is greatly appreciated.
The main idea behind the list and itemrenderers that you have a list (or datagrid) that displays like 30 items and then you can scroll to see the rest. Then you will only have 30 Itemrenderers that would be updated at once.
If you don't want to scroll you will need to distribute your item selection over several frames, something like that (untested, but you get the idea)
private static const ITEMS_AT_ONCE:int = 5000;
private var _currentIndex:int;
protected function selectAllHandler(event:MouseEvent):void
{
_currentIndex = 0;
addEventListener(Event.ENTER_FRAME, onEnterFrame); // this will call the onEnterFrame method on each frame rendered
}
private function onEnterFrame(e:Event):void
{
// make sure we don't run out of bounds of the dataprovider's length
var maxIndex:int = Math.min(_currentIndex + ITEMS_AT_ONCE, someList.length);
// set selection for the current bunch
for (var i:int = _currentIndex; i < maxIndex; i++)
{
someList[i].selected = true;
}
if (maxIndex == someList.length)
{
// We are done, remove enterframe listener
removeEventListener(Event.ENTER_FRAME, onEnterFrame);
// I'm not sure but don't you need to refresh the dataprovider to reflect the changes in the ItemRenderers ?
// (someList.dataProvider as ArrayCollection).refresh();
}
else
{
// update the _currentindex so we continue after this item on the next frame
_currentIndex = maxIndex;
}
Another possible solution - if you display all of them anyways - you might try to switch to a VGroup that will hold custom UIComponents (without MXML) for the items - this should speed up the rendering.

How to use Maki svg icons with Snap.svg?

I'm experimenting with Snap in order to use svg and need to be able to use the Maki icons defined in https://github.com/mapbox/maki.
My plan is to load the svg's I need, and then instantiate them for particular icons on a piece of Snap paper. But in order for this to work, I need to place the icon at a particular place on the paper, but I can't get translation to work. Neither one of the translation techniques below works; the code works as is, but always places the icon at the top left.
What am I missing? There's not enough documentation on Snap, and I don't know if the problem is with the way the Maki icon svg is defined, or my use of Snap.
var icon = Snap.load("maki/bicycle-24.svg", function(f) {
var g = f.select("g").clone();
// var g = f.select("#layer1").clone(); // also works
// g.transform("t120,120");
// var t = new Snap.Matrix();
// t.translate(120,120);
// g.transform(t);
paper.append(g);
});
The cloning needs to happen after the append, as when loading an svg in Snap its just a fragment.
So you will need to do something like...
paper.append(f);
var element = paper.select('#someId').clone();
element.transform( myTransform );
Thank you! That did the trick! And since Snap is so poorly documented, I'm going to insert the code here that allows a general solution.
// Base set from which markers are constructed
var iconSet = paper.group();
iconSet.attr({ class: 'hide' });
// Instantiations of icons
var markers = paper.g();
// Now, create SVG shape
var icon = Snap.load("maki/bicycle-24.svg", function(icon) {
// Add it to the icon set
iconSet.append(icon);
// Instantiate it and remove from main view
var element = paper.select('#svg4460'); // Copies it!
// var element = paper.select('#base'); // Selects something but doesn't work
// var element = paper.select('#layer1'); // Selects something but doesn't work
// var element = paper.select('#bicycle-24'); // Silent fail
element = element.clone();
element.remove();
// Clone this icon and move it
var t = new Snap.Matrix();
t.translate(10,120);
element.transform(t);
// Insert into main document view (markers)
markers.add(element);
});

Highlighting or Bolding the Borders of a kml Polygon

Hey after loading a kml file to google earth I was trying to have when a user clicks a certain polygon from the kml, to have that polygon highlighted.
So far I can record the click event, get the event type (KmlPlacemark) and grab its kml markup.
I tried doing something similar to this example where they add a placemark to the getFeatures of the kmlObject but both target and type don't seem to have 'getFeatures'. After looking around the documentation I think I might either want setOutline from Kml Polystyle class or setWidth() from KmlLineStyle class but am not sure. Also when I try something like target.setOutline(true); it doesn't work.
Can anyone tell me if I'm on the right track, hints to what I'm doing wrong, and if there's a better way to do this?
function recordEvent(event) {
var target = event.getTarget();
var type = target.getType();
if(type == "KmlPolygon") {
alert("KMLPolygon ");
}else if(type == "KmlPlacemark") {
// // get the data you want from the target.
var description = target.getDescription();
var balloon = target.getBalloonHtml();
var outputKml = target.getKml();
if ('getFeatures' in event) {
console.log("test");
event.getFeatures().appendChild(placemark);
}
console.log("hello?")
// target.setOutline(true);
console.log(outputKml);
}
};
google.earth.addEventListener(ge.getGlobe(), 'click', recordEvent);
Thanks!
I find the best way to do what you are asking is to:
Detect click events like you currently do
If clicked, create a new Style, then assign it to the target
var newStyle = ge.createStyle('');
// Assign your Style's attributes such as LabelStyle and IconStyle
// eg to set the scale of your label
newStyle.getLabelStyle().setScale(2.5);
// Set the Style
target.setStyleSelector(newStyle);
Edit to add in this link of a Google example showing it more in depth
https://code.google.com/apis/ajax/playground/#styling_placemarks_using_style_maps

d3 basic animations

Trying to follow along the tutorial here, but there isn't enough code presented to me to bridge the gaps.
Here is the fiddle I am working on to accomplish the same thing, with d3 loaded, however, the animation transitions are not concurrently happening, let alone at all, it is just changing the attributes, something I am already familiar with in SVG hard coding with JQuery selectors. So where am I going wrong, or missing the boat?
// example code doesn't work
var circle = svg.selectAll("circle");
circle.style("fill", "steelblue");
circle.attr("cy", 90);
circle.attr("r", 30);
// this does, but animations don't work
d3.selectAll('circle').style("fill", "steelblue");
d3.selectAll('circle').attr("cy", 90);
d3.selectAll('circle').attr("r", 30);
I am eventually trying to leverage the tweening of d3, but I cant get the basics off the ground. Thanks for you help in advance....
In the example code, svg is previously assigned to a d3 selection object:
var svg = d3.select("#chart-2").append("svg")
.attr("width", w)
.attr("height", h);
Therefore, you can use it to select the child elements, as in the original example.
Eg. your fiddle could be rewritten like so:
var svg = d3.select("#svg");
//svg is now a d3.selection object.
svg.on("click", function() {
var circle = svg.selectAll("circle");
circle.style("fill", "steelblue");
circle.attr("cy", 90);
circle.attr("r", 30);
});
Something to note about binding events using d3:
Within the anonymous function:
The event is bound to d3.event
The dom element - not the d3.selection object - is bound to this
If you pass an argument to the function, it will be bound to the data which is joined to the element.
Not really code, but should show what I mean:
var someD3Selection = d3.select("#someElement");
someD3Selection.on("click", function(boundData) {
d3.event.preventDefault(); // <-- here's the event
this; // <-- the actual dom element which is selected in someD3Selection
d3.select(this); // <-- same as someD3Selection.
});
Is this what you're looking for? The duration is optional but it's easier to see what's happening when it's a bit slower.
$('#svg').on('click', function() {
d3.selectAll('circle').style("fill", "grey").transition().duration(5000).style("fill", "steelblue").attr("cy", 90).attr("r", 30);
});

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