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

如果你想同时显示/隐藏多个视图,你可以使用TransitionSet(因为你不能同时播放2个“单个”过渡)

fun slideTopBottomVisibility(topLayout: View, bottomLayout: View, show: Boolean) {
    val topTransition: Transition = Slide(Gravity.TOP)
    topTransition.duration = 600
    topTransition.addTarget(topLayout)

    val bottomTransition: Transition = Slide(Gravity.BOTTOM)
    bottomTransition.duration = 600
    bottomTransition.addTarget(bottomLayout)

    val transitionSet = TransitionSet()
    transitionSet.addTransition(topTransition)
    transitionSet.addTransition(bottomTransition)

    TransitionManager.beginDelayedTransition(topLayout.parent as ViewGroup, transitionSet)
    topLayout.visibility = if (show) View.VISIBLE else View.GONE
    bottomLayout.visibility = if (show) View.VISIBLE else View.GONE
}

其他回答

当LinearLayout的可见性改变时,你可以通过创建LinearLayout的一个新的子类并覆盖setVisibility()来启动动画来启动正确的动画。考虑一下这样的事情:

public class SimpleViewAnimator extends LinearLayout
{
    private Animation inAnimation;
    private Animation outAnimation;

    public SimpleViewAnimator(Context context)
    {
        super(context);
    }

    public void setInAnimation(Animation inAnimation)
    {
        this.inAnimation = inAnimation;
    }

    public void setOutAnimation(Animation outAnimation)
    {
        this.outAnimation = outAnimation;
    }

    @Override
    public void setVisibility(int visibility)
    {
        if (getVisibility() != visibility)
        {
            if (visibility == VISIBLE)
            {
                if (inAnimation != null) startAnimation(inAnimation);
            }
            else if ((visibility == INVISIBLE) || (visibility == GONE))
            {
                if (outAnimation != null) startAnimation(outAnimation);
            }
        }

        super.setVisibility(visibility);
    }
}

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()
    }
}

如果你想同时显示/隐藏多个视图,你可以使用TransitionSet(因为你不能同时播放2个“单个”过渡)

fun slideTopBottomVisibility(topLayout: View, bottomLayout: View, show: Boolean) {
    val topTransition: Transition = Slide(Gravity.TOP)
    topTransition.duration = 600
    topTransition.addTarget(topLayout)

    val bottomTransition: Transition = Slide(Gravity.BOTTOM)
    bottomTransition.duration = 600
    bottomTransition.addTarget(bottomLayout)

    val transitionSet = TransitionSet()
    transitionSet.addTransition(topTransition)
    transitionSet.addTransition(bottomTransition)

    TransitionManager.beginDelayedTransition(topLayout.parent as ViewGroup, transitionSet)
    topLayout.visibility = if (show) View.VISIBLE else View.GONE
    bottomLayout.visibility = if (show) View.VISIBLE else View.GONE
}

其中一个简单的方法是:

containerView.setLayoutTransition(LayoutTransition())
containerView.layoutTransition.enableTransitionType(LayoutTransition.CHANGING)

随着Android 3.0 (Honeycomb)引入的新动画API,创建这样的动画非常简单。

将视图向下滑动一段距离:

view.animate().translationY(distance);

你可以稍后将视图滑回原来的位置,如下所示:

view.animate().translationY(0);

您还可以轻松地组合多个动画。下面的动画会将一个视图按高度向下滑动,同时淡入:

// Prepare the View for the animation
view.setVisibility(View.VISIBLE);
view.setAlpha(0.0f);

// Start the animation
view.animate()
    .translationY(view.getHeight())
    .alpha(1.0f)
    .setListener(null);

然后,您可以将视图淡出,并将其滑回原始位置。我们还设置了一个AnimatorListener,这样我们可以在动画完成后将视图的可见性设置为GONE:

view.animate()
    .translationY(0)
    .alpha(0.0f)
    .setListener(new AnimatorListenerAdapter() {
        @Override
        public void onAnimationEnd(Animator animation) {
            super.onAnimationEnd(animation);
            view.setVisibility(View.GONE);
        }
    });