Window Properties

Here is the source code for a web page containing JavaScript that:

opens child windows as the main (parent) window loads

This could have been done in response to the onLoad event, but here it's done another way.

modifies properties of the children
closes its child windows with the window.close() method...
...when parent closes or goes to a new page (onUnload()).
A child window refers to its parent as window.opener.

The Window object is the top-level object in Javascript.

One such object can create others.
They can modify each other's properties and sub-objects.

The document sub-object is particularly interesting. Its properties and methods include:

```
bgColor
```

```
fgColor
```

```
formName
```

```
forms
```

```
images
```

```
write()
```

```
title
```

```
URL
```

Caution: Netscape's handling of child windows is buggy.

For example, in some versions, Netscape crashes if you attempt to change a property of a non-existent child window.

Parent/Child Properties

Lab

Your task:

Make a copy of the example web page and modify it as follows.
Add a button to the form.
Reverse the given example so that the child window changes the parent's properties:

Change the parent window's background color (its bgcolor property).
- That is, assign a new value to window.opener.document.bgcolor.
Change the parent window's button label (its form.field.value property, where form is the name of the form in the parent document, and field is the name of the button).
- That is, assign a new value to window.opener.document.form.field.value.

Add a handler for the onUnload() event that closes the parent window when the child closes.

Solution

Don't peek unless you're stuck!

Extra for Experts

The child windows opened by our example are not resizable. Fix this.

Add a text field to the form in the parent window.
From the child, generate some text in your new text field in the parent window.
- Do this by modifying the value property of the text field object.
- The generated text should be the name of the winery selected in the child window.