假设我有一个垂直线性布局:

[v1]
[v2]

默认情况下,v1已经可见= GONE。我想用一个展开动画显示v1,同时下推v2。

我是这样做的:

Animation a = new Animation()
{
    int initialHeight;

    @Override
    protected void applyTransformation(float interpolatedTime, Transformation t) {
        final int newHeight = (int)(initialHeight * interpolatedTime);
        v.getLayoutParams().height = newHeight;
        v.requestLayout();
    }

    @Override
    public void initialize(int width, int height, int parentWidth, int parentHeight) {
        super.initialize(width, height, parentWidth, parentHeight);
        initialHeight = height;
    }

    @Override
    public boolean willChangeBounds() {
        return true;
    }
};

但是用这个解决方案,当动画开始时我有一个眨眼。我认为这是由于v1在应用动画之前显示全尺寸。

用javascript,这是一行jQuery!android有什么简单的方法吗?


当前回答

平滑动画请使用Handler运行方法.....享受展开/折叠动画

    class AnimUtils{

                 public void expand(final View v) {
                  int ANIMATION_DURATION=500;//in milisecond
        v.measure(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT);
        final int targtetHeight = v.getMeasuredHeight();

        v.getLayoutParams().height = 0;
        v.setVisibility(View.VISIBLE);
        Animation a = new Animation()
        {
            @Override
            protected void applyTransformation(float interpolatedTime, Transformation t) {
                v.getLayoutParams().height = interpolatedTime == 1
                        ? LayoutParams.WRAP_CONTENT
                        : (int)(targtetHeight * interpolatedTime);
                v.requestLayout();
            }

            @Override
            public boolean willChangeBounds() {
                return true;
            }
        };

        // 1dp/ms
        a.setDuration(ANIMATION_DURATION);

      // a.setDuration((int)(targtetHeight / v.getContext().getResources().getDisplayMetrics().density));
        v.startAnimation(a);
    }



    public void collapse(final View v) {
        final int initialHeight = v.getMeasuredHeight();

        Animation a = new Animation()
        {
            @Override
            protected void applyTransformation(float interpolatedTime, Transformation t) {
                if(interpolatedTime == 1){
                    v.setVisibility(View.GONE);
                }else{
                    v.getLayoutParams().height = initialHeight - (int)(initialHeight * interpolatedTime);
                    v.requestLayout();
                }
            }

            @Override
            public boolean willChangeBounds() {
                return true;
            }
        };

        // 1dp/ms
        a.setDuration(ANIMATION_DURATION);
       // a.setDuration((int)(initialHeight / v.getContext().getResources().getDisplayMetrics().density));
        v.startAnimation(a);
    }
}

使用下面的代码调用:

       private void setAnimationOnView(final View inactive ) {
    //I am applying expand and collapse on this TextView ...You can use your view 

    //for expand animation
    new Handler().postDelayed(new Runnable() {
        @Override
        public void run() {

            new AnimationUtililty().expand(inactive);

        }
    }, 1000);


    //For collapse
    new Handler().postDelayed(new Runnable() {
        @Override
        public void run() {

            new AnimationUtililty().collapse(inactive);
            //inactive.setVisibility(View.GONE);

        }
    }, 8000);

}

其他解决方案是:

               public void expandOrCollapse(final View v,String exp_or_colpse) {
    TranslateAnimation anim = null;
    if(exp_or_colpse.equals("expand"))
    {
        anim = new TranslateAnimation(0.0f, 0.0f, -v.getHeight(), 0.0f);
        v.setVisibility(View.VISIBLE);  
    }
    else{
        anim = new TranslateAnimation(0.0f, 0.0f, 0.0f, -v.getHeight());
        AnimationListener collapselistener= new AnimationListener() {
            @Override
            public void onAnimationStart(Animation animation) {
            }

            @Override
            public void onAnimationRepeat(Animation animation) {
            }

            @Override
            public void onAnimationEnd(Animation animation) {
            v.setVisibility(View.GONE);
            }
        };

        anim.setAnimationListener(collapselistener);
    }

     // To Collapse
        //

    anim.setDuration(300);
    anim.setInterpolator(new AccelerateInterpolator(0.5f));
    v.startAnimation(anim);
}

其他回答

下面是两个简单的kotlin扩展函数概述。

fun View.expand() {
    visibility = View.VISIBLE
    val animate = TranslateAnimation(0f, 0f, -height.toFloat(), 0f)
    animate.duration = 200
    animate.fillAfter = true
    startAnimation(animate)
}

fun View.collapse() {
    val animate = TranslateAnimation(0f, 0f, 0f, -height.toFloat() )
    animate.duration = 200
    animate.fillAfter = true
    startAnimation(animate)
}
/**
 * Animation that either expands or collapses a view by sliding it down to make
 * it visible. Or by sliding it up so it will hide. It will look like it slides
 * behind the view above.
 * 
 */
public class FinalExpandCollapseAnimation extends Animation
{
    private View mAnimatedView;
    private int mEndHeight;
    private int mType;
    public final static int COLLAPSE = 1;
    public final static int EXPAND = 0;
    private LinearLayout.LayoutParams mLayoutParams;
    private RelativeLayout.LayoutParams mLayoutParamsRel;
    private String layout;
    private Context context;

    /**
     * Initializes expand collapse animation, has two types, collapse (1) and
     * expand (0).
     * 
     * @param view
     *            The view to animate
     * @param type
     *            The type of animation: 0 will expand from gone and 0 size to
     *            visible and layout size defined in xml. 1 will collapse view
     *            and set to gone
     */
    public FinalExpandCollapseAnimation(View view, int type, int height, String layout, Context context)
    {
        this.layout = layout;
        this.context = context;
        mAnimatedView = view;
        mEndHeight = mAnimatedView.getMeasuredHeight();
        if (layout.equalsIgnoreCase("linear"))
            mLayoutParams = ((LinearLayout.LayoutParams) view.getLayoutParams());
        else
            mLayoutParamsRel = ((RelativeLayout.LayoutParams) view.getLayoutParams());
        mType = type;
        if (mType == EXPAND)
        {
            AppConstant.ANIMATED_VIEW_HEIGHT = height;
        }
        else
        {
            if (layout.equalsIgnoreCase("linear"))
                mLayoutParams.topMargin = 0;
            else
                mLayoutParamsRel.topMargin = convertPixelsIntoDensityPixels(36);
        }
        setDuration(600);
    }

    @Override
    protected void applyTransformation(float interpolatedTime, Transformation t)
    {
        super.applyTransformation(interpolatedTime, t);
        if (interpolatedTime < 1.0f)
        {
            if (mType == EXPAND)
            {
                if (layout.equalsIgnoreCase("linear"))
                {
                    mLayoutParams.height = AppConstant.ANIMATED_VIEW_HEIGHT
                            + (-AppConstant.ANIMATED_VIEW_HEIGHT + (int) (AppConstant.ANIMATED_VIEW_HEIGHT * interpolatedTime));
                }
                else
                {
                    mLayoutParamsRel.height = AppConstant.ANIMATED_VIEW_HEIGHT
                            + (-AppConstant.ANIMATED_VIEW_HEIGHT + (int) (AppConstant.ANIMATED_VIEW_HEIGHT * interpolatedTime));
                }
                mAnimatedView.setVisibility(View.VISIBLE);
            }
            else
            {
                if (layout.equalsIgnoreCase("linear"))
                    mLayoutParams.height = mEndHeight - (int) (mEndHeight * interpolatedTime);
                else
                    mLayoutParamsRel.height = mEndHeight - (int) (mEndHeight * interpolatedTime);
            }
            mAnimatedView.requestLayout();
        }
        else
        {
            if (mType == EXPAND)
            {
                if (layout.equalsIgnoreCase("linear"))
                {
                    mLayoutParams.height = AppConstant.ANIMATED_VIEW_HEIGHT;
                    mLayoutParams.topMargin = 0;
                }
                else
                {
                    mLayoutParamsRel.height = AppConstant.ANIMATED_VIEW_HEIGHT;
                    mLayoutParamsRel.topMargin = convertPixelsIntoDensityPixels(36);
                }
                mAnimatedView.setVisibility(View.VISIBLE);
                mAnimatedView.requestLayout();
            }
            else
            {
                if (layout.equalsIgnoreCase("linear"))
                    mLayoutParams.height = 0;
                else
                    mLayoutParamsRel.height = 0;
                mAnimatedView.setVisibility(View.GONE);
                mAnimatedView.requestLayout();
            }
        }
    }

    private int convertPixelsIntoDensityPixels(int pixels)
    {
        DisplayMetrics metrics = context.getResources().getDisplayMetrics();
        return (int) metrics.density * pixels;
    }
}

该类可以通过以下方式调用

   if (findViewById(R.id.ll_specailoffer_show_hide).getVisibility() == View.VISIBLE) {
                        ((ImageView) findViewById(R.id.iv_specialhour_seemore)).setImageResource(R.drawable.white_dropdown_up);

                        FinalExpandCollapseAnimation finalExpandCollapseAnimation = new FinalExpandCollapseAnimation(
                                findViewById(R.id.ll_specailoffer_show_hide),
                                FinalExpandCollapseAnimation.COLLAPSE,
                                SpecialOfferHeight, "linear", this);
                        findViewById(R.id.ll_specailoffer_show_hide)
                                .startAnimation(finalExpandCollapseAnimation);
                        ((View) findViewById(R.id.ll_specailoffer_show_hide).getParent()).invalidate();
                    } else {
                        ((ImageView) findViewById(R.id.iv_specialhour_seemore)).setImageResource(R.drawable.white_dropdown);

                        FinalExpandCollapseAnimation finalExpandCollapseAnimation = new FinalExpandCollapseAnimation(
                                findViewById(R.id.ll_specailoffer_show_hide),
                                FinalExpandCollapseAnimation.EXPAND,
                                SpecialOfferHeight, "linear", this);
                        findViewById(R.id.ll_specailoffer_show_hide)
                                .startAnimation(finalExpandCollapseAnimation);
                        ((View) findViewById(R.id.ll_specailoffer_show_hide).getParent()).invalidate();
                    }
public static void expand(final View v, int duration, int targetHeight) {
        v.measure(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT);
        v.getLayoutParams().height = 0;
        v.setVisibility(View.VISIBLE);
        ValueAnimator valueAnimator = ValueAnimator.ofInt(0, targetHeight);
        valueAnimator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
            @Override
            public void onAnimationUpdate(ValueAnimator animation) {
                v.getLayoutParams().height = (int) animation.getAnimatedValue();
                v.requestLayout();
            }
        });
        valueAnimator.setInterpolator(new DecelerateInterpolator());
        valueAnimator.setDuration(duration);
        valueAnimator.start();
    }
public static void collapse(final View v, int duration, int targetHeight) {
    ValueAnimator valueAnimator = ValueAnimator.ofInt(0, targetHeight);
    valueAnimator.setInterpolator(new DecelerateInterpolator());
    valueAnimator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
        @Override
        public void onAnimationUpdate(ValueAnimator animation) {
            v.getLayoutParams().height = (int) animation.getAnimatedValue();
            v.requestLayout();
        }
    });
    valueAnimator.setInterpolator(new DecelerateInterpolator());
    valueAnimator.setDuration(duration);
    valueAnimator.start();
}

我今天也遇到了同样的问题,我想这个问题的真正解决方案是这样的

<LinearLayout android:id="@+id/container"
android:animateLayoutChanges="true"
...
 />

您必须为所有涉及移位的最顶层布局设置此属性。如果你现在将一个布局的可见性设置为GONE,另一个将在消失的布局释放它时占据空间。会有一个默认的动画,这是某种“淡出”,但我认为你可以改变这个-但最后一个我没有测试,现在。


如果在RecyclerView项目中使用这个,在onBindViewHolder中设置视图的可见性来展开/折叠,并调用notifyItemChanged(position)来触发转换。

override fun onBindViewHolder(holder: ItemViewHolder, position: Int) {
        ...

        holder.list.visibility = data[position].listVisibility
        holder.expandCollapse.setOnClickListener {
            data[position].listVisibility = if (data[position].listVisibility == View.GONE) View.VISIBLE else View.GONE
            notifyItemChanged(position)
        }
    }

如果你在onBindViewHolder中执行昂贵的操作,你可以使用notifyItemChanged(位置,有效载荷)优化部分更改

private const val UPDATE_LIST_VISIBILITY = 1

    override fun onBindViewHolder(holder: ItemViewHolder, position: Int, payloads: MutableList<Any>) {
        if (payloads.contains(UPDATE_LIST_VISIBILITY)) {
            holder.list.visibility = data[position].listVisibility
        } else {
            onBindViewHolder(holder, position)
        }
    }

    override fun onBindViewHolder(holder: ItemViewHolder, position: Int) {
        ...

        holder.list.visibility = data[position].listVisibility
        holder.expandCollapse.setOnClickListener {
            data[position].listVisibility = if (data[position].listVisibility == View.GONE) View.VISIBLE else View.GONE
            notifyItemChanged(position, UPDATE_LIST_VISIBILITY)
        }
    }

我采用了@LenaYan的解决方案,但它并没有正常工作 对我来说(因为它在折叠和/或扩展之前将视图转换为0高度视图)并做了一些更改。

现在它工作得很好,通过获取视图之前的高度并开始扩展这个大小。坍缩也是一样的。

你可以简单地复制和粘贴下面的代码:

public static void expand(final View v, int duration, int targetHeight) {

    int prevHeight  = v.getHeight();

    v.setVisibility(View.VISIBLE);
    ValueAnimator valueAnimator = ValueAnimator.ofInt(prevHeight, targetHeight);
    valueAnimator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
        @Override
        public void onAnimationUpdate(ValueAnimator animation) {
            v.getLayoutParams().height = (int) animation.getAnimatedValue();
            v.requestLayout();
        }
    });
    valueAnimator.setInterpolator(new DecelerateInterpolator());
    valueAnimator.setDuration(duration);
    valueAnimator.start();
}

public static void collapse(final View v, int duration, int targetHeight) {
    int prevHeight  = v.getHeight();
    ValueAnimator valueAnimator = ValueAnimator.ofInt(prevHeight, targetHeight);
    valueAnimator.setInterpolator(new DecelerateInterpolator());
    valueAnimator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
        @Override
        public void onAnimationUpdate(ValueAnimator animation) {
            v.getLayoutParams().height = (int) animation.getAnimatedValue();
            v.requestLayout();
        }
    });
    valueAnimator.setInterpolator(new DecelerateInterpolator());
    valueAnimator.setDuration(duration);
    valueAnimator.start();
}

用法:

//Expanding the View
   expand(yourView, 2000, 200);

// Collapsing the View     
   collapse(yourView, 2000, 100);

很容易!

感谢LenaYan提供的初始代码!