As per https://developer.android.com/training/material/animations.html
The ViewAnimationUtils.createCircularReveal()
method enables you to
animate a clipping circle to reveal or hide a view.
To reveal a previously invisible view using this effect:
// previously invisible view
View myView = findViewById(R.id.my_view);
// get the center for the clipping circle
int cx = (myView.getLeft() + myView.getRight()) / 2;
int cy = (myView.getTop() + myView.getBottom()) / 2;
// get the final radius for the clipping circle
int finalRadius = Math.max(myView.getWidth(), myView.getHeight());
// create the animator for this view (the start radius is zero)
Animator anim =
ViewAnimationUtils.createCircularReveal(myView, cx, cy, 0, finalRadius);
// make the view visible and start the animation
myView.setVisibility(View.VISIBLE);
anim.start();
This is meant to reveal a view. How can I use this to circularly reveal an entire activity, without any shared elements?
Specifically, I'd like my searchActivity to circularly reveal from the search action button in the toolbar.
After looking for a solution for half a day without a result, I came up with an own implementation. I'm using a transparent activity with a matching root layout.
The root layout is a view which can then be revealed with createCircularReveal()
.
My code looks like this:
Theme Definition in styles.xml
<style name="Theme.Transparent" parent="Theme.AppCompat.Light.NoActionBar">
<item name="android:windowIsTranslucent">true</item>
<item name="android:statusBarColor">@android:color/transparent</item>
<item name="android:windowBackground">@android:color/transparent</item>
</style>
Activity Definition in AndroidManifest.xml
<activity
android:name=".ui.CircularRevealActivity"
android:theme="@style/Theme.Transparent"
android:launchMode="singleTask"
/>
then I declared a layout for my activity (I've chosen DrawerLayout, so that I can have a NavDrawer. Every layout should work here.)
<android.support.v4.widget.DrawerLayout
android:id="@+id/drawer_layout"
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
>
<FrameLayout
android:id="@+id/root_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@color/honey_melon"
>
<!-- Insert your actual layout here -->
</FrameLayout>
</android.support.v4.widget.DrawerLayout>
Important is the FrameLayout with the id root_layout
. This view will be revealed in the activity.
Finally I implemented CircularRevealActivity
and overwrote onCreate()
:
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
overridePendingTransition(R.anim.do_not_move, R.anim.do_not_move);
setContentView(R.layout.activity_reveal_circular);
if (savedInstanceState == null) {
rootLayout.setVisibility(View.INVISIBLE);
ViewTreeObserver viewTreeObserver = rootLayout.getViewTreeObserver();
if (viewTreeObserver.isAlive()) {
viewTreeObserver.addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {
@Override
public void onGlobalLayout() {
circularRevealActivity();
if (Build.VERSION.SDK_INT < Build.VERSION_CODES.JELLY_BEAN) {
rootLayout.getViewTreeObserver().removeGlobalOnLayoutListener(this);
} else {
rootLayout.getViewTreeObserver().removeOnGlobalLayoutListener(this);
}
}
});
}
}
}
It was important to put circularRevealActivity()
into a OnGlobalLayoutListener
, because the view needs to be drawn for the animation.
circularRevealActivity()
looks like Ishaan's proposal:
private void circularRevealActivity() {
int cx = rootLayout.getWidth() / 2;
int cy = rootLayout.getHeight() / 2;
float finalRadius = Math.max(rootLayout.getWidth(), rootLayout.getHeight());
// create the animator for this view (the start radius is zero)
Animator circularReveal = ViewAnimationUtils.createCircularReveal(rootLayout, cx, cy, 0, finalRadius);
circularReveal.setDuration(1000);
// make the view visible and start the animation
rootLayout.setVisibility(View.VISIBLE);
circularReveal.start();
}
Edit 1
The definition for R.anim.do_not_move
was added. However, it should work without that line too, if your design does not specify default transitions for activities. Let me know
R.anim.do_not_move:
<set xmlns:android="http://schemas.android.com/apk/res/android">
<translate
android:fromYDelta="0"
android:toYDelta="0"
android:duration="@android:integer/config_mediumAnimTime"
/>
</set>
To reverse the CircularReveal
animation swap the startRadius
and endRadius
arguments. Also you will need to setup an AnimatorListener
and in the onAnimationEnd()
callback method is where you can call finishAfterTransition()
. This is for when you press the up navigation
or click on the back button
.
If you want to reverse the circular reveal on leaving activity, use the following modification to onBackPressed().
@Override
public void onBackPressed() {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
int cx = rootLayout.getWidth();
int cy = 0;
float finalRadius = Math.max(rootLayout.getWidth(), rootLayout.getHeight());
Animator circularReveal = ViewAnimationUtils.createCircularReveal(rootLayout, cx, cy, finalRadius, 0);
circularReveal.addListener(new Animator.AnimatorListener() {
@Override
public void onAnimationStart(Animator animator) {
}
@Override
public void onAnimationEnd(Animator animator) {
rootLayout.setVisibility(View.INVISIBLE);
finish();
}
@Override
public void onAnimationCancel(Animator animator) {
}
@Override
public void onAnimationRepeat(Animator animator) {
}
});
circularReveal.setDuration(400);
circularReveal.start();
}else{
super.onBackPressed();
}
}
I think you can use ActivityOptionsCompat.makeClipRevealAnimation
.
[https://developer.android.com/reference/android/support/v4/app/ActivityOptionsCompat.html#makeClipRevealAnimation(android.view.View, int, int, int, int)](https://developer.android.com/reference/android/support/v4/app/ActivityOptionsCompat.html#makeClipRevealAnimation(android.view.View, int, int, int, int))
ou have to draw the circle view, and after that you should create an animation to it.
Creating the circle view:
public class Circle extends View {
private static final int START_ANGLE_POINT = 90;
private final Paint paint;
private final RectF rect;
private float angle;
public Circle(Context context, AttributeSet attrs) {
super(context, attrs);
final int strokeWidth = 40;
paint = new Paint();
paint.setAntiAlias(true);
paint.setStyle(Paint.Style.STROKE);
paint.setStrokeWidth(strokeWidth);
//Circle color
paint.setColor(Color.RED);
//size 200x200 example
rect = new RectF(strokeWidth, strokeWidth, 200 + strokeWidth, 200 + strokeWidth);
//Initial Angle (optional, it can be zero)
angle = 120;
}
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
canvas.drawArc(rect, START_ANGLE_POINT, angle, false, paint);
}
public float getAngle() {
return angle;
}
public void setAngle(float angle) {
this.angle = angle;
}
}
Creating the animation class to set the new angle:
public class CircleAngleAnimation extends Animation {
private Circle circle;
private float oldAngle;
private float newAngle;
public CircleAngleAnimation(Circle circle, int newAngle) {
this.oldAngle = circle.getAngle();
this.newAngle = newAngle;
this.circle = circle;
}
@Override
protected void applyTransformation(float interpolatedTime, Transformation transformation) {
float angle = oldAngle + ((newAngle - oldAngle) * interpolatedTime);
circle.setAngle(angle);
circle.requestLayout();
}
}
Put circle into your layout:
<com.package.Circle
android:id="@+id/circle"
android:layout_width="300dp"
android:layout_height="300dp" />
And finally starting the animation:
Circle circle = (Circle) findViewById(R.id.circle);
CircleAngleAnimation animation = new CircleAngleAnimation(circle, 240);
animation.setDuration(1000);
circle.startAnimation(animation);