Specifications

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Enable bitmap caching only when you need it, such as during the duration of an animation, and only on a few
objects at a time because it can be a memory-intensive operation. The best approach might be to change this
property at various times during the object’s life cycle, rather than setting it once.
Using filters
To improve rendering speeds, do not overuse filters such as DropShadowFilter. The expense of the filter is propor-
tional to the number of pixels in the object that you are applying the filter to. As a result, it is best to use filters on
smaller objects.
Using device text
Mixing device text and vector graphics can slow rendering speeds. For example, a DataGrid control that contains
both text and graphics inside a cell will be much slower to redraw than a DataGrid that contains just text.
Using clip masks
Using the scrollRect and mask properties of an object are expensive operations. Try to minimize the number of
times you use these properties.
Using large data sets
You can minimize overhead when working with large data sets.
Paging
When you use a DataService class to get your remote data, you might have a collection that does not initially load
all of its data on the client. You can prevent large amounts of data from traveling over the network and slowing
down your application while that data is processed using paging. The data that you get incrementally is referred
to as paged data, and the data that has not yet been received is pending data.
Paging data using the DataService class provides the following benefits:
• Maximum message size on the destination can be configured.
• If size exceeds the maximum value, multiple message batches are used.
• Client reassembles separate messages.
• Asynchronous data paging across the network.
• User interface elements can display portions of the collection without waiting for the entire collection to load.
For more information, see “Using Data Providers and Collections” on page 137 in the Adobe Flex 3 Developer
Guide.