How to do android scale animation based on view's position on screen and focus that view in centre?

问题

I want animation like this: Calendar Animation

I want to scale animation on calendar and focus on current date to centre. I am new in android animation, I do some stuff for scaling:

zoom_in.xml

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android"
android:fillAfter="true">
<scale
    android:duration="1000"
    android:fromXScale="1"
    android:fromYScale="1"
    android:pivotX="50%"
    android:pivotY="50%"
    android:toXScale="2"
    android:toYScale="2" />
</set>

but using this, it scaling the calendar to centre but I want the current date in centre. Anybody have an idea how to do this whole animation? any help would be appreciated.

回答1:

you need to get position of the view/content that you want to be in center, because you need to do some translation

here example zoom to center of TextView with random position inside a ConstraintView

if you want to zoom to specific area you can change the difX and difY formula

float layoutWitdh = layout.getWidth();
        float layoutHeight = layout.getHeight();

        float x = view.getX();
        float y = view.getY();
        float w = view.getWidth();
        float h = view.getHeight();

        float difX = (layoutWitdh - w) / 2 - x;
        float difY = (layoutHeight - h) / 2 - y;

        view.animate().translationX(difX).translationY(difY).scaleY(5).scaleX(5).setDuration(1000);

来源：https://stackoverflow.com/questions/62794012/how-to-do-android-scale-animation-based-on-views-position-on-screen-and-focus-t