Netscape Navigator does not automatically set the vertical scroll height of the browser window for the Digital Teacher web-based lesson.
To correct this problem, you must manually set the scroll position to the maximum expected height of the largest text element in a lesson so that the full text content can be scrolled down to its maximum height (depth).
You set this position by changing the value of one of the following variables in your lesson template file depending on the Digital Teacher web lesson style.
var scrollHt= 5000; Single-page style
var scrollHtm= 700; Multi-page style
For example, the lesson page shown in the figure contains inline reading text whose height is 1000. To be able to scroll down to the position at 1000, the scrollHtm must be set to the position eqaul to (or larger than) 1000.
Note: Since you have no way to determine the exact height of the text in advance, you must find it by trial and error, by setting the value to approximate positions. If its position is set to 900, you will only be able to scroll down to 900, and will not see the rest of the reading text.
Tip: For the multi-page style, if text size for every page is small enough to fit into the browser window, you can set the position to 0 in order to disable the vertical scrollbar.
(Single-page style lesson page only)
The fill-in-the-blank (or multiple short answer) type question usually contains multiple text entry boxes, which the student is asked to type in answers.
On Internet Explorer, the student can move to the next box using the Tab key. With Netscape, however, pressing the Tab key will either move him to the address box, or scroll the current position up to the top, rendering the use of the Tab key useless. This is the problem associated with Netscape Navigator.
The table below lists the problems associated with the Digital Teacher web-based lesson when the student uses the browser menu bar and toolbar.
| When the student action is | The browser | When the performance result is set to |
The impact is |
|
| with Netscape Navigator | with Internet Explorer | |||
| File | New Window | (Netscape) Loads the previous web page in the History list on top of the current page, which is the Digital Teacher lesson page. (IE) Loads the current page ion top of the current page, which is the Digital Teacher lesson page. | Not Collect |
(If the previous web page was the Student Login page)
The student can possibly open another instance of the Digital Teacher lesson that is currently open. |
The student can possibly open multiple instances of the Digital Teacher lesson that is currently open. |
| Collect |
(If the previous web page was the Student Login page)
The student can attempt to open another instance of the Digital Teacher lesson that is currently open. However, the verification process rejects this attempt. |
The student can attempt to submit multiple instances of the Digital Teacher lesson’s performance result.
However, the verification process rejects this attempt. |
||
| File | Open |
Allows the user (the student) to load a web page in the current browser window.
The Digital Teacher lesson page that is currently open is unloaded. |
Not Collect |
The student is NOT allowed go back to the lesson page using the BACK button since the history is intentionally set to FORWARD in the Digital Teacher lesson page.
The student must go through the Student Login procedure to re-open the Digital Teacher lesson. |
Same as Navigator |
| Collect |
Same as above.
However, if the student attempts to re-open the lesson from the Student Login page, the verification process rejects this attempt. |
Same as Navigator | ||
| View | Show or Hide toolbars |
Resizes the browser window.
This has the same effect as resizing the window manually. |
Not Collect |
Netscape Navigator has a host of problems when the user resizes the browser window in a DHML application.
|
There are no problems. However, the Digital Teacher lesson will be terminated anyway. |
| Collect | Same as above | Same as above | ||
| View | Reloading or Refreshing | Not Collect |
(In the HTM type lesson) No problem (In the ASP type lesson) All the student inputs (answers) will be cleared when the page is reloaded or the browser window is refreshed. |
Same as Navigator | |
| Collect |
The current lesson session will be terminated without warning.
The student is NOT allowed to re-open the lesson. |
Same as Navigator | ||
| View | Changing Fonts View | Preferences | Not Collect |
The current lesson session will be terminated without warning.
The student can reopen the lesson from the Student Login page. |
No problem | |
| Collect |
Same as above
However, the student is NOT allowed to reopen the lesson from the Student Login page. |
No problem | ||
| View | Source | Not Collect | The student can view the source. However, the correct answers are not available to the student. | Same as Navigator | |
| Collect | The student is NOT allowed to view the source. The lesson will be terminated without warning. | The student can view the source. However, the correct answers are not available to the student. | ||
| Go | BACK or HISTORY |
Allows the student to surf to another web page from the Digital Teacher web lesson page.
Note: As you're probably aware of, there is no absolute way to trap the user inside a web page on a modern browser. Although some tricks seem to make this possible, there are too many ways for the user to move from one page to another. Warning the student in advance can be the best way to discourage the student from attempting to use these menus. |
Not Collect |
(In the HTM type lesson)
The student can go back or forward. (In the ASP type lesson) The student can go back to the previous page (such as to the Student Login page), but cannot return to the lesson page using the FORWARD button. To return to the lesson page, the student must go through the Student Login procedure. |
(In the HTM type lesson)
The student can go back or forward. (In the ASP type lesson) The student can go back to the previous page (such as to the Student Login page), and can return to the lesson page either using the FORWARD button or the Student Login procedure. When the student returns to the lesson page, all the previous answers are cleared. (See the Tip below this table.) |
| Collect | Attempting to go back to the previous page using the BACK button from the Digital Teacher lesson page will load the Data Missing page, resulting from the expired POST operation. The lesson will be terminated. |
The student can go back to the previous page (such as to the Student Login page), and can return to the lesson page using the FORWARD button. When the student returns to the lesson page, all the previous answers are cleared.
The student cannot return to the lesson page through the Student Login procedure. (See the Tip below this table.) |
||
Tip: To stop the student from going back to the previous web page using the BACK button while he or she is in the Digital Teacher lesson page, you may want to include the JavaScript statement history.forward() within the immediate previous page (such as the Student Login page). The statement will send the student forward, that is, to the current page, forcing him to stay in the Digital Teacher lesson page as a result.
If you include this JavaScript to the previous page, do not forget to provide the student with the way to exit the Digital Teacher lesson page. For example, replace the history.back() statement for the Digital Teacher lesson window’s Exit link (located to the left of the Submit link) with an absolute path such as location = ../dtLoginNT.htm.
Also, read the next chapter to see how to remove the browser menu and tool bar altogether from the Digital Teacher web lesson window.
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