Image filtration with motion layout

In this blog, we are going to learn some cool features of motion layout. Image filtration is one of them.

MotionLayout:-

Motion Layout is a new class available in the ConstraintLayout 2.0 library. By using this class we can manage motion and widget animation in their application.

First of all, we have to implement dependency.

implementation 'androidx.constraintlayout:constraintlayout:2.0.0-alpha2'

1	implementation 'androidx.constraintlayout:constraintlayout:2.0.0-alpha2'

Implement this in your build.greadle (app) file.

Lets’s start some code:-

Now open your layout file in my case it is activity_main.xml.

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.motion.widget.MotionLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/motion_layout"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    app:layoutDescription="@xml/demo_motion"
    tools:context=".MainActivity">

    <androidx.constraintlayout.utils.widget.ImageFilterView
        android:id="@+id/image"
        android:layout_width="100dp"
        android:layout_height="100dp"
        app:srcCompat="@drawable/sun_set" />

</androidx.constraintlayout.motion.widget.MotionLayout>

<?xml version="1.0" encoding="utf-8"?>

<androidx.constraintlayout.motion.widget.MotionLayout xmlns:android="http://schemas.android.com/apk/res/android"

xmlns:app="http://schemas.android.com/apk/res-auto"

xmlns:tools="http://schemas.android.com/tools"

android:id="@+id/motion_layout"

android:layout_width="match_parent"

android:layout_height="match_parent"

app:layoutDescription="@xml/demo_motion"

tools:context=".MainActivity">

<androidx.constraintlayout.utils.widget.ImageFilterView

android:id="@+id/image"

android:layout_width="100dp"

android:layout_height="100dp"

app:srcCompat="@drawable/sun_set" />

</androidx.constraintlayout.motion.widget.MotionLayout>

In this layout file, We have MotionLayout as a view group and ImageFilterView as a child view. To perform Image filtration we need to use ImageFilterView.

app:layoutDescription="@xml/demo_motion"

1	app:layoutDescription="@xml/demo_motion"

In this layout file, we use layoutDescription attribute and parse a layout file motion demo_motion in it. Because layoutDesciption holds a reference of your motion_scene layout file.

<?xml version="1.0" encoding="utf-8"?>
<MotionScene xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:motion="http://schemas.android.com/apk/res-auto">

    <Transition
        motion:constraintSetEnd="@id/end"
        motion:constraintSetStart="@id/start"
        motion:duration="1000"
        motion:interpolator="linear">
        <OnSwipe
            motion:dragDirection="dragRight"
            motion:touchAnchorId="@+id/image"
            motion:touchAnchorSide="right" />
    </Transition>

    <ConstraintSet android:id="@+id/start">
        <Constraint
            android:id="@id/image"
            android:layout_width="100dp"
            android:layout_height="100dp"
            android:layout_marginStart="8dp"
            motion:layout_constraintBottom_toBottomOf="parent"
            motion:layout_constraintStart_toStartOf="parent"
            motion:layout_constraintTop_toTopOf="parent">
            <CustomAttribute
                motion:attributeName="saturation"
                motion:customFloatValue="1" />
        </Constraint>
    </ConstraintSet>

    <ConstraintSet android:id="@+id/end">
        <Constraint
            android:id="@id/image"
            android:layout_width="100dp"
            android:layout_height="100dp"
            android:layout_marginEnd="8dp"
            motion:layout_constraintBottom_toBottomOf="parent"
            motion:layout_constraintEnd_toEndOf="parent"
            motion:layout_constraintTop_toTopOf="parent">
            <CustomAttribute
                motion:attributeName="saturation"
                motion:customFloatValue="0" />
        </Constraint>
    </ConstraintSet>

</MotionScene>

<?xml version="1.0" encoding="utf-8"?>

<MotionScene xmlns:android="http://schemas.android.com/apk/res/android"

xmlns:motion="http://schemas.android.com/apk/res-auto">

<Transition

motion:constraintSetEnd="@id/end"

motion:constraintSetStart="@id/start"

motion:duration="1000"

motion:interpolator="linear">

<OnSwipe

motion:dragDirection="dragRight"

motion:touchAnchorId="@+id/image"

motion:touchAnchorSide="right" />

</Transition>

<Constraint

android:id="@id/image"

android:layout_width="100dp"

android:layout_height="100dp"

android:layout_marginStart="8dp"

motion:layout_constraintBottom_toBottomOf="parent"

motion:layout_constraintStart_toStartOf="parent"

motion:layout_constraintTop_toTopOf="parent">

<CustomAttribute

motion:attributeName="saturation"

motion:customFloatValue="1" />

</Constraint>

</ConstraintSet>

<Constraint

android:id="@id/image"

android:layout_width="100dp"

android:layout_height="100dp"

android:layout_marginEnd="8dp"

motion:layout_constraintBottom_toBottomOf="parent"

motion:layout_constraintEnd_toEndOf="parent"

motion:layout_constraintTop_toTopOf="parent">

<CustomAttribute

motion:attributeName="saturation"

motion:customFloatValue="0" />

</Constraint>

</ConstraintSet>

</MotionScene>

This is the file that defines the type of motion/animation we want and what the starting/ending constraints are.

Here we defined a Transition (the animation) with duration & a start/endpoint to the layouts. And also a swipe Trigger on the image (with up direction) — which adds interactivity.

Specifying the saturation can be done simply by using a CustomAttribute:

<CustomAttribute motion:attributeName="saturation" motion:customFloatValue="1" />

1	<CustomAttribute motion:attributeName="saturation" motion:customFloatValue="1" />

Therefore we define saturation values 1 and 0 to get the filter effect.

As a result of saturation manipulation, we get a filter effect on our image.

We define two ConstraintSet children in our xml. Start and end positions of that image.

Finally, we have achieved Image filtration with motion layout.

Anand Kashyap 31 January 2020

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Image filtration with motion layout