Animate visibility of a view from gone to visible

问题:

I have a view that is invisible by default(Just for the first time).

Now I need to switch the visibility to VISIBLE with this animation:

if (myView.getVisibility() == View.INVISIBLE) {
    myView.setVisibility(View.VISIBLE);
    myView.animate().translationY(0);
 }

(Like the SnackBar default animation)

But this isn't working. It will turn visible with default animation

Is there any simple way that I could achieve this?

Note

I'm animating my view to dismiss, like this:

myView.animate().translationY(myView.getHeight());

回答1:

You can do this using XML animation.

Create a slide-up animation XML using set and alpha and put this XML into your resource anim folder.

slide_up.xml

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

    <translate
        android:duration="500"
        android:fromYDelta="100%"
        android:toYDelta="0" />
</set>

USE:

Use AnimationUtils.loadAnimation() to load animation from XML and set and start animation using .startAnimation() method.

Here is an example:

ImageView imageView = (ImageView) findViewById(R.id.imageView);

// slide-up animation
Animation slideUp = AnimationUtils.loadAnimation(this, R.anim.slide_up);

if (imageView.getVisibility() == View.INVISIBLE) {
    imageView.setVisibility(View.VISIBLE);
    imageView.startAnimation(slideUp);
}

Hope this will help~

回答2:

Add animations using ConstraintLayout

Just add below code above the views whose visibility is updated:

TransitionManager.beginDelayedTransition(constraintLayout)

Note:

• ConstraintLayout will only perform animation on its direct children since it only knows when you change layout parameters and constraints on the children that it handles.
• ConstraintLayout only animates layout related changes.

For more see this post https://robinhood.engineering/beautiful-animations-using-android-constraintlayout-eee5b72ecae3

回答3:

Based on this answer:

with this methods, I can set the visibility of my view to VISIBLE with a slideUp animation(Like snackbar animation):

int getScreenHeight() {
    DisplayMetrics displaymetrics = new DisplayMetrics();
    activity.getWindowManager().getDefaultDisplay().getMetrics(displaymetrics);
    return displaymetrics.heightPixels;
}

public void animateOnScreen(View view) {
    final int screenHeight = getScreenHeight();
    ObjectAnimator animator = ObjectAnimator.ofFloat(view, "y", screenHeight, (screenHeight * 0.8F));
    animator.setInterpolator(new DecelerateInterpolator());
    animator.start();
}

Then I can use it like this:

if (myView.getVisibility() == View.INVISIBLE) {
    myView.setVisibility(View.VISIBLE);
    animateOnScreen(myView);
}