JavaScript Examples Bible - UserWorks Technologies

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JavaScript Examples Bible: The Essential Companion to JavaScript Bible
windowObject.open()
shows all the elements necessary to create a new window that has all the right stuff
on most platforms. The new window object reference is assigned to a global variable,
newWindow. Before a new window is generated, the script looks to see if the
window has never been generated before (in which case newWindow would be
null) or, for newer browsers, the window is closed. If either condition is true, the
window is created with the open() method. Otherwise, the existing window is
brought forward with the focus() method (NN3+ and IE4+).
As a safeguard against older browsers, the script manually adds an opener property
to the new window if one is not already assigned by the open() method. The
current window object reference is assigned to that property.
Due to the timing problem that afflicts all IE generations, the HTML assembly and
writing to the new window is separated into its own function that is invoked after a
50 millisecond delay (NN goes along for the ride, but it could accommodate the
assembly and writing without the delay). To build the string that is eventually written
to the document, I use the += (add-by-value) operator, which appends the string
on the right side of the operator to the string stored in the variable on the left side.
In this example, the new window is handed an -level line of text to display.
Listing 16-26: Creating a New Window
New Window
var newWindow
function makeNewWindow() {
if (!newWindow || newWindow.closed) {
newWindow = window.open(“”,””,”status,height=200,width=300”)
if (!newWindow.opener) {
newWindow.opener = window
}
// force small delay for IE to catch up
setTimeout(“writeToWindow()”, 50)
} else {
// window’s already open; bring to front
newWindow.focus()
}
}
function writeToWindow() {
// assemble content for new window
var newContent = “One Sub Window”
newContent += “This window is brand new.”
newContent += “”
// write HTML to new window document
newWindow.document.write(newContent)
newWindow.document.close() // close layout stream
}