I am working on an Android Kotlin project. I am applying animation on views. Starting from the basics, I am trying to animate an image view from the bottom of the screen to the center of the screen.
I have an XML layout with the following code.
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout 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:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@color/colorPrimaryDark"
tools:context=".MainActivity">
<LinearLayout
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toTopOf="parent"
android:orientation="vertical"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
<ImageView
android:id="@+id/main_image_logo"
android:src="@drawable/memento_text_logo"
android:layout_width="@dimen/main_logo_image_width"
android:layout_height="wrap_content" />
<TextView
android:textColor="@android:color/white"
android:id="@+id/main_tv_slogan"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/main_slogan"
/>
</LinearLayout>
</androidx.constraintlayout.widget.ConstraintLayout>
I am animating the logo image translating from the bottom to the center (where it is originally) in the activity with the following code.
private fun animateMainLogo() {
val valueAnimator = ValueAnimator.ofFloat(0f, main_image_logo.y)
valueAnimator.addUpdateListener {
val value = it.animatedValue as Float
main_image_logo.translationY = value
}
valueAnimator.interpolator = LinearInterpolator()
valueAnimator.duration = 1000
valueAnimator.start()
}
When I run the code, it is not animating the view. It is just there where it is and static. What is wrong with my code and how can I fix it?
translationY
of view in layout is 0. If you want to animate it from bottom to current position - you should change translationY
values from some positive value to 0.
private fun animateLogo() {
val translationYFrom = 400f
val translationYTo = 0f
val valueAnimator = ValueAnimator.ofFloat(translationYFrom, translationYTo).apply {
interpolator = LinearInterpolator()
duration = 1000
}
valueAnimator.addUpdateListener {
val value = it.animatedValue as Float
main_image_logo?.translationY = value
}
valueAnimator.start()
}
Same thing can be done this way:
private fun animateLogo() {
main_image_logo.translationY = 400f
main_image_logo.animate()
.translationY(0f)
.setInterpolator(LinearInterpolator())
.setStartDelay(1000)
.start()
}
Add this lines to LinearLayout
and ConstraintLayout
because without them LinearLayout
will cut of parts of animated view when it is outside of LinearLayout
bounds.
android:clipChildren="false"
android:clipToPadding="false"
Or make main_image_logo
direct child of root ConstraintLayout
. Here is result:
The technical post webpages of this site follow the CC BY-SA 4.0 protocol. If you need to reprint, please indicate the site URL or the original address.Any question please contact:yoyou2525@163.com.