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

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=)

其他回答

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);
        }
    });

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;
}
}

通过Kotlin扩展,你可以这样使用:

enum class SlideDirection{
    UP,
    DOWN,
    LEFT,
    RIGHT
}

enum class SlideType{
    SHOW,
    HIDE
}

fun View.slideAnimation(direction: SlideDirection, type: SlideType, duration: Long = 250){
    val fromX: Float
    val toX: Float
    val fromY: Float
    val toY: Float
    val array = IntArray(2)
    getLocationInWindow(array)
    if((type == SlideType.HIDE && (direction == SlideDirection.RIGHT || direction == SlideDirection.DOWN)) ||
        (type == SlideType.SHOW && (direction == SlideDirection.LEFT || direction == SlideDirection.UP))   ){
        val displayMetrics = DisplayMetrics()
        val windowManager = context.getSystemService(Context.WINDOW_SERVICE) as WindowManager
        windowManager.defaultDisplay.getMetrics(displayMetrics)
        val deviceWidth = displayMetrics.widthPixels
        val deviceHeight = displayMetrics.heightPixels
        array[0] = deviceWidth
        array[1] = deviceHeight
    }
    when (direction) {
        SlideDirection.UP -> {
            fromX = 0f
            toX = 0f
            fromY = if(type == SlideType.HIDE) 0f else (array[1] + height).toFloat()
            toY = if(type == SlideType.HIDE) -1f * (array[1] + height)  else 0f
        }
        SlideDirection.DOWN -> {
            fromX = 0f
            toX = 0f
            fromY = if(type == SlideType.HIDE) 0f else -1f * (array[1] + height)
            toY = if(type == SlideType.HIDE) 1f * (array[1] + height)  else 0f
        }
        SlideDirection.LEFT -> {
            fromX = if(type == SlideType.HIDE) 0f else 1f * (array[0] + width)
            toX = if(type == SlideType.HIDE) -1f * (array[0] + width) else 0f
            fromY = 0f
            toY = 0f
        }
        SlideDirection.RIGHT -> {
            fromX = if(type == SlideType.HIDE) 0f else -1f * (array[0] + width)
            toX = if(type == SlideType.HIDE) 1f * (array[0] + width) else 0f
            fromY = 0f
            toY = 0f
        }
    }
    val animate = TranslateAnimation(
        fromX,
        toX,
        fromY,
        toY
    )
    animate.duration = duration
    animate.setAnimationListener(object: Animation.AnimationListener{
        override fun onAnimationRepeat(animation: Animation?) {

        }

        override fun onAnimationEnd(animation: Animation?) {
            if(type == SlideType.HIDE){
                visibility = View.INVISIBLE
            }
        }

        override fun onAnimationStart(animation: Animation?) {
            visibility = View.VISIBLE
        }

    })
    startAnimation(animate)
}

扩展示例:

view.slideAnimation(SlideDirection.UP, SlideType.HIDE)//to make it disappear through top of the screen
view.slideAnimation(SlideDirection.DOWN, SlideType.SHOW)//to make it reappear from top of the screen

view.slideAnimation(SlideDirection.DOWN, SlideType.HIDE)//to make it disappear through bottom of the screen
view.slideAnimation(SlideDirection.UP, SlideType.SHOW)//to make it reappear from bottom of the screen

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);
    }
}

我在理解和应用公认的答案时遇到了困难。我需要更多的背景知识。现在我已经搞清楚了,下面是一个完整的例子:

MainActivity.java

public class MainActivity extends AppCompatActivity {

    Button myButton;
    View myView;
    boolean isUp;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        myView = findViewById(R.id.my_view);
        myButton = findViewById(R.id.my_button);

        // initialize as invisible (could also do in xml)
        myView.setVisibility(View.INVISIBLE);
        myButton.setText("Slide up");
        isUp = false;
    }

    // slide the view from below itself to the current position
    public void slideUp(View view){
        view.setVisibility(View.VISIBLE);
        TranslateAnimation animate = new TranslateAnimation(
                0,                 // fromXDelta
                0,                 // toXDelta
                view.getHeight(),  // fromYDelta
                0);                // toYDelta
        animate.setDuration(500);
        animate.setFillAfter(true);
        view.startAnimation(animate);
    }

    // slide the view from its current position to below itself
    public void slideDown(View view){
        TranslateAnimation animate = new TranslateAnimation(
                0,                 // fromXDelta
                0,                 // toXDelta
                0,                 // fromYDelta
                view.getHeight()); // toYDelta
        animate.setDuration(500);
        animate.setFillAfter(true);
        view.startAnimation(animate);
    }

    public void onSlideViewButtonClick(View view) {
        if (isUp) {
            slideDown(myView);
            myButton.setText("Slide up");
        } else {
            slideUp(myView);
            myButton.setText("Slide down");
        }
        isUp = !isUp;
    }
}

activity_mail.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="com.example.slideview.MainActivity">

    <Button
        android:id="@+id/my_button"
        android:layout_centerHorizontal="true"
        android:layout_marginTop="100dp"
        android:onClick="onSlideViewButtonClick"
        android:layout_width="150dp"
        android:layout_height="wrap_content"/>

    <LinearLayout
        android:id="@+id/my_view"
        android:background="#a6e1aa"
        android:orientation="vertical"
        android:layout_alignParentBottom="true"
        android:layout_width="match_parent"
        android:layout_height="200dp">

    </LinearLayout>

</RelativeLayout>

笔记

感谢这篇文章为我指明了正确的方向。它比本页上的其他答案更有帮助。 如果你想从屏幕上的视图开始,那么不要将它初始化为INVISIBLE。 因为我们是完全在屏幕外制作动画,所以没有必要将它设置为INVISIBLE。如果你的动画不是完全脱离屏幕,那么你可以添加一个alpha动画,并使用AnimatorListenerAdapter设置可见性。 动画文档