public static class FlutterFragment.CachedEngineFragmentBuilder extends Object
FlutterFragment
that uses a cached FlutterEngine
with arguments
that correspond to the values set on this Builder
.
Subclasses of FlutterFragment
that do not introduce any new arguments can use this
Builder
to construct instances of the subclass without subclassing this Builder
. MyFlutterFragment f = new
FlutterFragment.CachedEngineFragmentBuilder(MyFlutterFragment.class) .someProperty(...)
.someOtherProperty(...) .build<MyFlutterFragment>();
Subclasses of FlutterFragment
that introduce new arguments should subclass this
CachedEngineFragmentBuilder
to add the new properties:
FlutterFragment
subclass has a no-arg constructor.
CachedEngineFragmentBuilder
.
CachedEngineFragmentBuilder
's no-arg constructor and invoke the
super constructor to set the FlutterFragment
subclass: public MyBuilder()
{ super(MyFlutterFragment.class); }
createArgs()
, call through to the super
method, then add the new properties as arguments in the Bundle
.
CachedEngineFragmentBuilder
subclass is defined, the FlutterFragment
subclass can be instantiated as follows. MyFlutterFragment f = new MyBuilder()
.someExistingProperty(...) .someNewProperty(...) .build<MyFlutterFragment>();
Modifier | Constructor and Description |
---|---|
protected |
CachedEngineFragmentBuilder(Class<? extends FlutterFragment> subclass,
String engineId) |
Modifier and Type | Method and Description |
---|---|
<T extends FlutterFragment> |
build()
Constructs a new
FlutterFragment (or a subclass) that is configured based on
properties set on this CachedEngineFragmentBuilder . |
protected Bundle |
createArgs()
Creates a
Bundle of arguments that are assigned to the new FlutterFragment . |
FlutterFragment.CachedEngineFragmentBuilder |
destroyEngineWithFragment(boolean destroyEngineWithFragment)
Pass
true to destroy the cached FlutterEngine when this FlutterFragment is destroyed, or false for the cached FlutterEngine to
outlive this FlutterFragment . |
FlutterFragment.CachedEngineFragmentBuilder |
renderMode(RenderMode renderMode)
Render Flutter either as a
RenderMode.surface or a RenderMode.texture . |
FlutterFragment.CachedEngineFragmentBuilder |
shouldAttachEngineToActivity(boolean shouldAttachEngineToActivity)
Whether or not this
FlutterFragment should automatically attach its Activity
as a control surface for its FlutterEngine . |
FlutterFragment.CachedEngineFragmentBuilder |
transparencyMode(TransparencyMode transparencyMode)
Support a
TransparencyMode.transparent background within FlutterView , or
force an TransparencyMode.opaque background. |
protected CachedEngineFragmentBuilder(@NonNull Class<? extends FlutterFragment> subclass, @NonNull String engineId)
@NonNull public FlutterFragment.CachedEngineFragmentBuilder destroyEngineWithFragment(boolean destroyEngineWithFragment)
true
to destroy the cached FlutterEngine
when this FlutterFragment
is destroyed, or false
for the cached FlutterEngine
to
outlive this FlutterFragment
.@NonNull public FlutterFragment.CachedEngineFragmentBuilder renderMode(@NonNull RenderMode renderMode)
RenderMode.surface
or a RenderMode.texture
. You
should use surface
unless you have a specific reason to use texture
. texture
comes with a significant performance impact, but texture
can be displayed
beneath other Android View
s and animated, whereas surface
cannot.@NonNull public FlutterFragment.CachedEngineFragmentBuilder transparencyMode(@NonNull TransparencyMode transparencyMode)
TransparencyMode.transparent
background within FlutterView
, or
force an TransparencyMode.opaque
background.
See TransparencyMode
for implications of this selection.
@NonNull public FlutterFragment.CachedEngineFragmentBuilder shouldAttachEngineToActivity(boolean shouldAttachEngineToActivity)
FlutterFragment
should automatically attach its Activity
as a control surface for its FlutterEngine
.
Control surfaces are used to provide Android resources and lifecycle events to plugins
that are attached to the FlutterEngine
. If shouldAttachEngineToActivity
is
true then this FlutterFragment
will connect its FlutterEngine
to the
surrounding Activity
, along with any plugins that are registered with that FlutterEngine
. This allows plugins to access the Activity
, as well as receive Activity
-specific calls, e.g., Activity.onNewIntent(Intent)
. If shouldAttachEngineToActivity
is false, then this FlutterFragment
will not
automatically manage the connection between its FlutterEngine
and the surrounding
Activity
. The Activity
will need to be manually connected to this FlutterFragment
's FlutterEngine
by the app developer. See FlutterEngine.getActivityControlSurface()
.
One reason that a developer might choose to manually manage the relationship between the
Activity
and FlutterEngine
is if the developer wants to move the FlutterEngine
somewhere else. For example, a developer might want the FlutterEngine
to outlive the surrounding Activity
so that it can be used later in a different
Activity
. To accomplish this, the FlutterEngine
will need to be disconnected
from the surrounding Activity
at an unusual time, preventing this FlutterFragment
from correctly managing the relationship between the FlutterEngine
and the surrounding Activity
.
Another reason that a developer might choose to manually manage the relationship between
the Activity
and FlutterEngine
is if the developer wants to prevent, or
explicitly control when the FlutterEngine
's plugins have access to the surrounding
Activity
. For example, imagine that this FlutterFragment
only takes up part
of the screen and the app developer wants to ensure that none of the Flutter plugins are able
to manipulate the surrounding Activity
. In this case, the developer would not want
the FlutterEngine
to have access to the Activity
, which can be accomplished
by setting shouldAttachEngineToActivity
to false
.
@NonNull protected Bundle createArgs()
@NonNull public <T extends FlutterFragment> T build()
FlutterFragment
(or a subclass) that is configured based on
properties set on this CachedEngineFragmentBuilder
.