Moving colors Android Studio

Question

i am developing an android application. In this application i want to move colors as in the picture below.

1)I've tried to rotate background drawable:This

2)I've tried animation-list but this wasn't the solution.

Layout

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

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">

<ImageView
    android:id="@+id/imageView"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_centerInParent="true"
    android:background="@drawable/border"
    android:contentDescription="@string/qr"
    android:cropToPadding="true"
    android:padding="10dp"
    android:scaleType="centerCrop"
    />

@drawable/border

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

<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle">
<gradient
    android:angle="270"
    android:endColor="@color/colorYellowGreen"
    android:type="linear"
    android:centerColor="@color/colorBlue"
    android:startColor="@color/colorPink" />

<corners android:radius="5dp" />

</shape>

NOTE: I am not looking for rotating view. Because there is content inside imageview. So do not suggest to use ViewPropertyAnimator class

Answer 1

One way to do it would be the gradient with a timer. Here are two examples, one changes the colors and the other changes the angle hence creating a rotation effect.

You can tweak them for your purposes.

But be wary of the performance depending on how fast you want it to change.

Rotation effect

//Call this once to change gradient angle
private fun startAngleChangeJob() {
    var shape = imageView.background
    var borderGrad = shape as GradientDrawable

    var timer = fixedRateTimer("colorTimer", false, 0L, 100) {
        var ori = borderGrad.orientation.ordinal
        var newOri = (ori + 1) % 7

        [email protected] {
            borderGrad.orientation = GradientDrawable.Orientation.values()[newOri]
        }
    }
}

Color change effect

//Call this once in onCreate to change gradient colors
private fun startColorChangeJob() {
    var timer = fixedRateTimer("colorTimer", false, 0L, 100) {
        var shape = imageView.background
        var borderGrad = shape as GradientDrawable
        var colors = borderGrad.colors
        var colorsNew = IntArray(colors!!.size)
        for (i in colors.indices) {
            var newInd = (i + 1) % colors.size
            colorsNew[newInd] = colors[i]
        }
        [email protected] {
            borderGrad.colors = colorsNew
        }
    }
}

Color shift effect

for (i in colors.indices) {
            var oldColor = Color.valueOf(colors[i])
            var red = (oldColor.red() + 0.2f) % 1.0f
            var green = (oldColor.green() + 0.2f) % 1.0f
            var blue = (oldColor.blue() + 0.2f) % 1.0f
            colorsNew[i] = Color.argb(1.0f, red, green, blue)
        }