How To Make An Application the Backdrop
One of the Newton 2.x OS Q&As
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This document was exported on 7/23/97.
How To Make An Application the Backdrop (8/23/96)
- Q: Is there a way to programmatically change the backdrop application?
A: Yes, but only if the "new" backdrop application is one of your applications. Do not set another application to be the backdrop application. GetRoot():BlessApp(appSymbol) will close the current backdrop application and open the new backdrop application if necessary. Note that appSymbol must be a valid application symbol of a current installed and active application. BlessApp does NOT verify that an application can become the backdrop (for instance, it doesn't check the 'noBackdrop flag for an application). For this reason, BlessApp must only be used on your own applications. See the Newton DTS Q&A, "How to Prevent an Application from Becoming a Backdrop" for more information about the 'noBackdrop flag.
Do not call BlessApp from within a part's installScript or removeScript. If you want to do something like this, use a delayed call to use BlessApp.