C H A P T E R 3
Views
About Views
3-5
application base view. (Think of the view hierarchy as a tree structure in which
the tree is turned upside down with its root at the top. The top-level parent view is
the root view.)
the tree is turned upside down with its root at the top. The top-level parent view is
the root view.)
Figure 3-2 shows the set of views instantiated from the templates shown in
Figure 3-1. Note that this example is simplified in that it shows a separate template
for each view. In practice, multiple views often share a single template. Also, this
example doesn't show templates that are built on other protos.
Figure 3-1. Note that this example is simplified in that it shows a separate template
for each view. In practice, multiple views often share a single template. Also, this
example doesn't show templates that are built on other protos.
Figure 3-2
View hierarchy
Arrows indicate a
reference to parent/child
reference to parent/child
Templates
(permanent, read-only)
Views
(transient, writable)
Arrows indicate a
reference to protos
reference to protos
Parent View
{_proto:
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}
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}
Child Template C
{
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}
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}
Child Template B
{
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}
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}
Child Template D
{
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}
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}
Parent Template
{
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viewChildren:[]
}
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viewChildren:[]
}
Child Template A
{
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viewChildren:[]
}
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viewChildren:[]
}
Child View B
{
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_parent:
_proto:
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}
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_parent:
_proto:
.
}
Child View A
{_parent:
_proto:
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}
_proto:
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}
Child View D
{
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_parent:
_proto:
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}
.
_parent:
_proto:
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}
Child View C
{_parent:
_proto:
.
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}
_proto:
.
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}