Cooler modal popup example – how to open multiple popups, scrolling pop ups per page

Some time back I came up with a cooler modal pop up window using CSS3 and JavaScript specifically for mobile webkit browsers. The example that I presented had only a single button, a click on it would open a modal pop up window.

In this post I have a similar example but this time multiple pop ups can be opened from the same page. Opening multiple pop up’s from a single page was requested by some of my readers. And here it is. I will not go deep into explaining the bits and parts of how to create a pop up window. You can go through my previous post for that. But first let’s check a demo (meant only for web-kit based browsers):

Demo link (open in iOS or Android’s browser, you can also test this in Chrome or Safari in your computer) :  http://rialab.jbk404.site50.net/coolermultiplemodalpopup/

Open multiple pops from a single page

How to run this in Firefox, IE and other browsers?
For this you need to make changes in the CSS file. Add CSS3 prefixes for other browsers similarly as it is there for -webkit- . CSS3 junkies would already know what I am talking about.

CSS3 Transformations showing content outside overflow:hidden region in Firefox/Android

Some time back I was implementing a functionality for Firefox browsers on Android devices and I found a strange problem - For Firefox > 18 on Android devices if I move an element using CSS3 Transformations inside a parent container with overflow:hidden, then part of the element being moved is displayed outside the overflowed region. It seems like when you move the element it just discards the overflow:hidden property and everything is revealed rather. Normally the content outside overflow:hidden should be cut off from view.

I have a simple demo http://rialab.jbk404.site50.net/ffandroidissue/ - an image which is bigger than the container div is moved using CSS3 Transformations. The  div has a overflow:hidden set to it. There are two buttons. Click on them to see the various results. The first button causes the issue whereas the second button resolves it.

So this is what causes the issue – moving the image using CSS3 Transformations (for eg. transform:translateX(value);) inside a container with overflow:hidden

And this is what solves it – strange !!
Adding a background color and an opacity to the container element like this,

#container.noissue{
-moz-perspective: 1000px;
overflow: hidden;
background:#ccc;
width: 100px;
height: 50px;
display: block;
position:absolute;
top:50px;
right:50px;
  background:#ccc;
  opacity:0.99;
}

Check out the demo in Firefox on an Android device. I am not sure if anybody has encountered this situation. But this definitely seems to be a bug in Firefox for Android’s. This is not seen for other browsers.

Cooler modal Popup window with fade effect – gradient colors, border, drop shadow and center position

In one of my earlier post I talked on creating a cool modal pop up window using CSS3 and JavaScript. It had fade effect upon opening and closing of the pop up. Based on the same lines, I have created a much cooler pop up, actually asked by one of my readers. It now has gradient colors, much more eye catching – vibrant color :) , it has a header, a content area, border, drop shadow and it is also now centrally positioned always, even if you go from portrait to landscape mode and vice-versa.

Look at the demo first, you can view in both mobile web-kit browsers (iOS ,Android) and desktop browsers (Chrome, Safari):

http://rialab.jbk404.site50.net/coolermodalpopup/

The concept remains the same. I have discussed it in details in my previous post. Just refer that in case it is not clear. In this post, I will just talk briefly on the changes that I have implemented.

HTML changes
No major changes. I just externalized the CSS and JavaScript. So they are now in external files, which I reference in the index.html file. The HTML code is very simple and self explanatory. Download the code and check it out. A download link is provided below.

JavaScript changes
I have made some changes in the architecture of the popup creation. The showPopUpMessage() function now takes a header, main content, width and height parameters.

//show the modal overlay and popup window
function showPopUpMessage(modalWindowHeader,modalWindowContent,width,height) {
     //code goes here
}

Since this new pop up has a header, so I have kept a separate method for the header. You can call a function to create the header content and then set it in the showPopUpMessage() function. This will help if you have multiple instances of pop up to create. Here is the function,

/* Common header for Pop Ups */
function createPopUpHeader(title)
{
  //return the header after creating
  //create header for modal window area
  modalWindowHeader = document.createElement("div");
  modalWindowHeader.className = "modalWindowHeader";
  modalWindowHeader.innerHTML = "<p>" + title + "</p>";

  return modalWindowHeader;
}

Similarly, I have kept a separate function to create the contents of the modal pop up. You can customize the method and change the contents. Again, this will help in creating more than one pop up window. Here is how I have done it for this example,

function createPopUpContent(msg)
{
  //return the content after creating
  //create modal window content area
  modalWindowContent = document.createElement("div");
  modalWindowContent.className = "modalWindowContent";

  modalWindowContent.innerHTML = "<p style='text-align:center; margin-top:10px;'>" + msg + "</p>";
  //create the place order button
  okBtn = document.createElement("div");
  okBtn.className = "redBtn okBtn";
  okBtn.innerHTML = "<p>OK</p>";
  okBtn.addEventListener(endEvent,function(){ hidePopUpMessage(); },false);

  modalWindowContent.appendChild(okBtn);
  return modalWindowContent;
}

And now once I have the header and the content I can call the showPopUpMessage() function to launch the pop up,

showPopUpMessage(createPopUpHeader("This is a cool popup"),createPopUpContent("I am a cool modal pop up. I have gradient colors, border colors, drop shadow and I am always positioned at the center!!"),250,300);

I have passed a width of 250 and a height of 300. You can change it as per your requirement.

Positioning the modal pop up always at the center

This is done by calculating the window width and height and then subtracting it by the popup width and height and then dividing by 2. This is how I did it,

modalWindowElement.style.left = (window.innerWidth - width) / 2 + "px";
modalWindowElement.style.top = (window.innerHeight - height) / 2 + "px";

Now, to keep the window always at the center, even when you resize the browser window or move from portrait to landscape and then back to portrait, I have registered a window resize event listener and then calculate the left and top position again as we did above. You can find this is inside the handleResize() function.

//when window is resized
window.addEventListener("resize",handleResize,false); //resizing is useful only when popups are opened

And finally one more change. In this example, if you see at the top of the javascript file, I have detected if the device browser is touch enabled. And then accordingly I register touch based events for touch devices and mouse events for desktop devices. So this is a common code and you do not have to hardcode anything. I have a separate post for this, you can go through it.

Style changes
Only new class selectors have been added for the modal window header, modal window content, gradient buttons. Rest of them is pretty simple and understandable.

So this is it. This is a much cooler pop up, better looking than my previous boring and dull pop up. Hope you have enjoyed it. Check out the demo or download the code.

Download
Download the source code here.

Updates
1) How to open multiple pop ups from one page – Check this post.

A look at iScroll – native way of scrolling content in mobile webkit

Mobile web kit browsers do not allow you to scroll content inside a fixed size container or a div element. If you are a mobile web developer developing apps for iPhone and Android, you must have faced this problem before. If you use overflow:auto or overflow:scroll and expect to scroll the overflown content then you would rather see your entire web page being scrolled vertically. This happens because it is the default behavior of DOM touch events to scroll the page.

Just to overcome this problem I recently came across a javascript library iScroll which allows native way of scrolling content inside a fixed width/height element for mobile web kit browsers. So using iScroll you can have a fixed header/footer with position:absolute and a scrolling central content area.

iScroll uses hardware accelerated CSS3 transitions and transformations to scroll the content and it behaves exactly like the native way of scrolling in iPhone apps. iScroll is very easy to use – download the iscroll javascript library (which is available for download in the home page) and call it in your html page. Then set up your HTML and CSS and you are good to go. Latest version of iScroll at the time of writing this post was iScroll4, so you can download the library and use that. iScroll4 also supports a whole lot of other features like pinch-to-zoom, pull-to-refresh e.t.c to make mobile web development easier. I will not go into the details of iScroll as the site has all the necessary information and is very well documented. I believe you will find everything there to get you started in 5 mins.

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