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

使用ValueAnimator:

ValueAnimator expandAnimation = ValueAnimator.ofInt(mainView.getHeight(), 400);
expandAnimation.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
    @Override
    public void onAnimationUpdate(final ValueAnimator animation) {
        int height = (Integer) animation.getAnimatedValue();
        RelativeLayout.LayoutParams lp = (LayoutParams) mainView.getLayoutParams();
        lp.height = height;
    }
});


expandAnimation.setDuration(500);
expandAnimation.start();

其他回答

如果你不想扩展或折叠所有的方式-这里是一个简单的HeightAnimation -

import android.view.View;
import android.view.animation.Animation;
import android.view.animation.Transformation;

public class HeightAnimation extends Animation {
    protected final int originalHeight;
    protected final View view;
    protected float perValue;

    public HeightAnimation(View view, int fromHeight, int toHeight) {
        this.view = view;
        this.originalHeight = fromHeight;
        this.perValue = (toHeight - fromHeight);
    }

    @Override
    protected void applyTransformation(float interpolatedTime, Transformation t) {
        view.getLayoutParams().height = (int) (originalHeight + perValue * interpolatedTime);
        view.requestLayout();
    }

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

用法:

HeightAnimation heightAnim = new HeightAnimation(view, view.getHeight(), viewPager.getHeight() - otherView.getHeight());
heightAnim.setDuration(1000);
view.startAnimation(heightAnim);

展开/折叠视图的最佳解决方案:

    @Override
    public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
        View view = buttonView.getId() == R.id.tb_search ? fSearch : layoutSettings;
        transform(view, 200, isChecked
            ? ViewGroup.LayoutParams.WRAP_CONTENT
            : 0);
    }

    public static void transform(final View v, int duration, int targetHeight) {
        int prevHeight  = v.getHeight();
        v.setVisibility(View.VISIBLE);
        ValueAnimator animator;
        if (targetHeight == ViewGroup.LayoutParams.WRAP_CONTENT) {
            v.measure(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT);
            animator = ValueAnimator.ofInt(prevHeight, v.getMeasuredHeight());
        } else {
            animator = ValueAnimator.ofInt(prevHeight, targetHeight);
        }
        animator.addUpdateListener(animation -> {
            v.getLayoutParams().height = (animation.getAnimatedFraction() == 1.0f)
                    ? targetHeight
                    : (int) animation.getAnimatedValue();
            v.requestLayout();
        });
        animator.setInterpolator(new LinearInterpolator());
        animator.setDuration(duration);
        animator.start();
    }

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);
}

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)
        }
    }

使用ValueAnimator:

ValueAnimator expandAnimation = ValueAnimator.ofInt(mainView.getHeight(), 400);
expandAnimation.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
    @Override
    public void onAnimationUpdate(final ValueAnimator animation) {
        int height = (Integer) animation.getAnimatedValue();
        RelativeLayout.LayoutParams lp = (LayoutParams) mainView.getLayoutParams();
        lp.height = height;
    }
});


expandAnimation.setDuration(500);
expandAnimation.start();