We are happy to announce the release of ConstraintLayout 2.0 beta 2.
It’s available from the google maven repository:
dependencies {
implementation 'com.android.support.constraint:constraint-layout:2.0.0-beta2'
}
or if using the AndroidX packages:
dependencies {
implementation 'androidx.constraintlayout:constraintlayout:2.0.0-beta2'
}
Documentation is available on https://developer.android.com/reference/android/support/constraint/classes.html
Examples are available on https://github.com/googlesamples/android-ConstraintLayoutExamples
New in Beta 2
Flow
New attributes were added to control the behavior of the last chain, in similar manner to flow_first* attributes:
flow_lastHorizontalStyle : spread|spread_inside|packed
flow_lastVerticalStyle : spread|spread_inside|packed
flow_lastVerticalBias : float
flow_lastHorizontalBias : float
MotionLayout
APIs additions
- MotionLayout.TransitionListener no longer has the method allowsTransition. This was replaced with the MotionScene.Transition.setEnable
- Added APIs to construct a MotionScene and Transition programmatically and manipulate them.
Transition ID
You can now name transitions with an ID using the attribute
MotionScene.Transition MotionLayout.
getTransition(int id)
<Transition
android:id="@id/tobigsceen" ...
|
Transition Disable
Now you can disable and enable Transitions in XML and programmatically. A <
Transition> now has an attribute
transitionDisable. You can also enable or disable them programmatically with
Transition.setEnable(true) and query with
Transition.isEnabled().
Important: This replaces the callback “
allowsTransition” in the interface
MotionLayout.TransitionListener
View Velocity
public void getViewVelocity(View view, float posOnViewX, float posOnViewY, float[] returnVelocity, int type) {
|
Accessing the Velocity of an animating view. You can get the velocity a view is moving at.
It takes the coordinate on the view and returns the velocity of the view.
There are 4 types of velocities it can return. It can return static or dynamic, pre or post layout.
The static velocity does not incorporate the actual motion driven by touch.
public final static int VELOCITY_POST_LAYOUT = 0;
public final static int VELOCITY_LAYOUT = 1;
public final static int VELOCITY_STATIC_POST_LAYOUT = 2;
public final static int VELOCITY_STATIC_LAYOUT = 3;
To aid in understanding how to use it, we have included a utility view MotionTelltales based on MockView but showing the velocity of 25 points on the view.
Key Trigger redirection
Now a KeyTrigger can trigger a method on another view using the attribute triggerReceiver.
<KeyTrigger
motion:triggerReceiver="@+id/view" ...
|
Bugfixes
Several issues where fixed in beta 2:
| Motion Layout nested scrolling issue | 133624931 |
| Alpha 4 Layout Weights not working properly | 130580479 |
| ConstraintLayout does not respect minHeight with wrap_content | 130437914 |
| [MotionLayout] getProgress() Value Gets Reset When The Container Layout Animates. | 112521093 |
| [MotionLayout] Fragments in ViewPager sometimes are not drawn | 123379505 |
| MotionLayout animation does not work inside fragment | 122929956 |
| ConstraintLayout:2.0.0-alpha4 no longer preserves view scaling properly with MotionLayout | 130115829 |
| Child view not centered when ConstraintLayout size changes | 133273843 |
| [ConstraintLayout 2.0.0-alpha5] Regression in MotionLayout when scrolling a scrollable view | 131572132 |
| Height of nested constraint layout child not measured correctly in ConstraintLayout 2.0.0-alpha4+ (including beta1) | 133202039 |
| [ConstraintLayout 2.0.0-alpha5] Regression in MotionLayout modifying a ConstraintSet | 131874827 |
| Constrain Layout 2.0.0 Alpha 4 to Beta 1 | 134841040 |
| Flow verticalAlign="baseline" not working | 134533710 |
| ConstraintLayout Group and Barrier is not working in dynamic feature module. | 133032779 |
| ConstraintLayout:2.0.0-alpha4 MotionLayout does not respect parent padding | 130561744 |
| app:showPaths crashes on transition with a duration smaller than 16 ms | 134086361 |
| PlaceHolder doesn't display | 132951221 |
| [MotionLayout] Migrate MotionLayout to NestledScrolling3 and override functionality | 128914828 |
| Maybe useless code in MotionLayout class | 131532235 |
| Placeholder emptyVisibility attribute is incorrect | 131747094 |
| Barrier is ignored | 132651309 |
| Request to programmatically change autoTransition | 132878306 |
| Handle Snackbar + FAB with MotionLayout | 133541548 |
| Problem when trying to wrap chains of width-constrained views | 134137982 |
| MotionLayout animating incorrectly when used in a recyclerview | 118289003 |
| Animatinos in recyclerview end in unexpected states | 118289936 |
| TextView is clipped when using nested ConstraintLayouts and constraintDimensionRatio | 134082517 |
| android:gravity does not work as expected in ConstraintLayout 2.0.0-alpha4+ (including beta1) | 132651320 |
| 2.0 B1 bug / changed behavior | 133465553 |
| ConstraintLayout does not measure height correctly when using wrap_content and layout_constrainedHeight is set to true. | 132314169 |
| ConstraintLayout will not wrap TextView to the correct height when using wrap_content and app:layout_constrainedHeight="true" | 123551995 |
| Buttons in Flow has text aligned to left (and alignment behaves strange) | 133809201 |
| adding constarint from kotlin is not respected in beta , works fine in alpha2 version | 133184664 |
| When the View referenced by Flow has a child View, the layout is wrong. | 133092993 |
| Flow does not work well with 0dp | 133326448 |
| MotionLayout not triggering animation after scrolling a list | 122676392 |
| Setting MotionScene in code to MotionLayout (Not working same as if we set layoutDescription in MotionLayout in xml) | 116674308 |
| Allow KeyTrigger to call methods on a different view | 132457332 |
| Constraint not respected when using the ID of the parent instead of `parent` in XML. | 133201550 |
