我有一个线性布局,我想显示或隐藏与动画,推动布局向上或向下每当我改变其可见性。

我在那里看过一些样品,但没有一个适合我的需要。

我已经为动画创建了两个xml文件,但我不知道当我改变线性布局的可见性时如何启动它们。


当前回答

if (filter_section.getVisibility() == View.GONE) {
    filter_section.animate()
            .translationY(filter_section.getHeight()).alpha(1.0f)
            .setListener(new AnimatorListenerAdapter() {
                @Override
                public void onAnimationStart(Animator animation) {
                    super.onAnimationStart(animation);
                    filter_section.setVisibility(View.VISIBLE);
                    filter_section.setAlpha(0.0f);
                }
            });
} else {
    filter_section.animate()
            .translationY(0).alpha(0.0f)
            .setListener(new AnimatorListenerAdapter() {
                @Override
                public void onAnimationEnd(Animator animation) {
                    super.onAnimationEnd(animation);
                    filter_section.setVisibility(View.GONE);
                }
            });
}

其他回答

我有一个角落的情况,我的视图高度仍然是0所以。

import android.animation.Animator;
import android.animation.AnimatorListenerAdapter;
import android.view.View;

public final class AnimationUtils {

  public static void slideDown(final View view) {
        view.animate()
                .translationY(view.getHeight())
                .alpha(0.f)
                .setListener(new AnimatorListenerAdapter() {
                    @Override
                    public void onAnimationEnd(Animator animation) {
                        // superfluous restoration
                        view.setVisibility(View.GONE);
                        view.setAlpha(1.f);
                        view.setTranslationY(0.f);
                    }
                });
    }

    public static void slideUp(final View view) {
        view.setVisibility(View.VISIBLE);
        view.setAlpha(0.f);

        if (view.getHeight() > 0) {
            slideUpNow(view);
        } else {
            // wait till height is measured
            view.post(new Runnable() {
                @Override
                public void run() {
                    slideUpNow(view);
                }
            });
        }
    }

    private static void slideUpNow(final View view) {
        view.setTranslationY(view.getHeight());
        view.animate()
                .translationY(0)
                .alpha(1.f)
                .setListener(new AnimatorListenerAdapter() {
                    @Override
                    public void onAnimationEnd(Animator animation) {
                        view.setVisibility(View.VISIBLE);
                        view.setAlpha(1.f);
                    }
                });
    }

}

使用ObjectAnimator

private fun slideDown(view: View) {
    val height = view.height
    ObjectAnimator.ofFloat(view, View.TRANSLATION_Y, 0f, height.toFloat()).apply {
        duration = 1000
        start()
    }
}

private fun slideUp(view: View) {
    val height = view.height
    ObjectAnimator.ofFloat(view, View.TRANSLATION_Y, height.toFloat(), 0f)).apply {
        duration = 1000
        start()
    }
}

使用这个类:

public class ExpandCollapseExtention {

 public static void expand(View view) {
    view.setVisibility(View.VISIBLE);

    final int widthSpec = View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED);
    final int heightSpec = View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED);
    view.measure(widthSpec, heightSpec);

    ValueAnimator mAnimator = slideAnimator(view, 0, view.getMeasuredHeight());
    mAnimator.start();
}


public static void collapse(final View view) {
    int finalHeight = view.getHeight();

    ValueAnimator mAnimator = slideAnimator(view, finalHeight, 0);

    mAnimator.addListener(new Animator.AnimatorListener() {

        @Override
        public void onAnimationEnd(Animator animator) {               
            view.setVisibility(View.GONE);
        }


        @Override
        public void onAnimationStart(Animator animation) {

        }


        @Override
        public void onAnimationCancel(Animator animation) {

        }


        @Override
        public void onAnimationRepeat(Animator animation) {

        }
    });
    mAnimator.start();
}


private static ValueAnimator slideAnimator(final View v, int start, int end) {

    ValueAnimator animator = ValueAnimator.ofInt(start, end);

    animator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {

        @Override
        public void onAnimationUpdate(ValueAnimator valueAnimator) {

            int value = (Integer) valueAnimator.getAnimatedValue();
            ViewGroup.LayoutParams layoutParams = v.getLayoutParams();
            layoutParams.height = value;
            v.setLayoutParams(layoutParams);
        }
    });
    return animator;
}
}

最简单的解决方案:在持有视图的容器上设置android:animateLayoutChanges="true"。

如果你有一个如下所示的布局,这个容器中所有视图的可见性变化都将自动动画化。

<LinearLayout android:id="@+id/container"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:animateLayoutChanges="true"
    >

    <Views_which_change_visibility>

</LinearLayout>

你可以在动画布局变化- Android开发者上找到更多细节

这是我的解决方案。只需要获取视图的引用并调用这个方法:

public static void animateViewFromBottomToTop(final View view){

    view.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {

        @Override
        public void onGlobalLayout() {

            view.getViewTreeObserver().removeOnGlobalLayoutListener(this);

            final int TRANSLATION_Y = view.getHeight();
            view.setTranslationY(TRANSLATION_Y);
            view.setVisibility(View.GONE);
            view.animate()
                .translationYBy(-TRANSLATION_Y)
                .setDuration(500)
                .setStartDelay(200)
                .setListener(new AnimatorListenerAdapter() {

                    @Override
                    public void onAnimationStart(final Animator animation) {

                        view.setVisibility(View.VISIBLE);
                    }
                })
                .start();
        }
    });
}

不需要做任何其他事情=)