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

你可以使用Transition或Animator来改变要展开/折叠的部分的可见性,或者使用不同布局的ConstraintSet。

最简单的一个是使用motionLayout与2个不同的布局和constraintSets改变从一个布局到另一个按钮点击。可以在布局之间进行更改

val constraintSet = ConstraintSet()
constraintSet.clone(this, R.layout.layout_collapsed)

val transition = ChangeBounds()
transition.interpolator = AccelerateInterpolator(1.0f)
transition.setDuration(300)

TransitionManager.beginDelayedTransition(YOUR_VIEW, transition)
constraintSet.applyTo(YOUR_VIEW)

使用过渡api

RotateX.kt

我在gif中使用改变rotationX的过渡api创建了一个。

class RotateX : Transition {

    @Keep
    constructor() : super()

    @Keep
    constructor(context: Context, attrs: AttributeSet) : super(context, attrs)

    override fun getTransitionProperties(): Array<String> {
        return TRANSITION_PROPERTIES
    }

    override fun captureStartValues(transitionValues: TransitionValues) {
        captureValues(transitionValues)
    }

    override fun captureEndValues(transitionValues: TransitionValues) {
        captureValues(transitionValues)
    }

    override fun createAnimator(
        sceneRoot: ViewGroup,
        startValues: TransitionValues?,
        endValues: TransitionValues?
    ): Animator? {

        if (startValues == null || endValues == null) return null

        val startRotation = startValues.values[PROP_ROTATION] as Float
        val endRotation = endValues.values[PROP_ROTATION] as Float
        if (startRotation == endRotation) return null

        val view = endValues.view
        // ensure the pivot is set
        view.pivotX = view.width / 2f
        view.pivotY = view.height / 2f
        return ObjectAnimator.ofFloat(view, View.ROTATION_X, startRotation, endRotation)
    }

    private fun captureValues(transitionValues: TransitionValues) {
        val view = transitionValues.view
        if (view == null || view.width <= 0 || view.height <= 0) return
        transitionValues.values[PROP_ROTATION] = view.rotationX
    }

    companion object {

        private const val PROP_ROTATION = "iosched:rotate:rotation"
        private val TRANSITION_PROPERTIES = arrayOf(PROP_ROTATION)
    }
}

创建目标扩展按钮的XML文件

    <?xml version="1.0" encoding="utf-8"?>
    <transitionSet
        xmlns:android="http://schemas.android.com/apk/res/android"
        android:interpolator="@android:interpolator/fast_out_slow_in">
    
        <transition class="com.smarttoolfactory.tutorial3_1transitions.transition.RotateX">
            <targets>
                <target android:targetId="@id/ivExpand" />
            </targets>
        </transition>
    
        <autoTransition android:duration="200" />
    
    </transitionSet>

My layout to be expanded or collapsed


<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools">

    <com.google.android.material.card.MaterialCardView
        android:id="@+id/cardView"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginHorizontal="4dp"
        android:layout_marginVertical="2dp"
        android:clickable="true"
        android:focusable="true"
        android:transitionName="@string/transition_card_view"
        app:cardCornerRadius="0dp"
        app:cardElevation="0dp"
        app:cardPreventCornerOverlap="false">


        <androidx.constraintlayout.widget.ConstraintLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:paddingTop="16dp"
            android:paddingBottom="16dp">

            <androidx.appcompat.widget.AppCompatImageView
                android:id="@+id/ivAvatar"
                android:layout_width="40dp"
                android:layout_height="40dp"
                android:layout_marginStart="16dp"
                android:layout_marginTop="8dp"
                android:scaleType="centerCrop"
                app:layout_constraintStart_toStartOf="parent"
                app:layout_constraintTop_toTopOf="parent"
                tools:src="@drawable/avatar_1_raster" />

            <androidx.appcompat.widget.AppCompatImageView
                android:id="@+id/ivExpand"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_marginEnd="8dp"
                android:padding="8dp"
                app:layout_constraintEnd_toEndOf="parent"
                app:layout_constraintTop_toTopOf="parent"
                app:srcCompat="@drawable/ic_baseline_expand_more_24" />

            <TextView
                android:id="@+id/tvTitle"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_marginStart="12dp"
                android:layout_marginTop="6dp"
                android:text="Some Title"
                android:textSize="20sp"
                android:textStyle="bold"
                app:layout_constraintStart_toEndOf="@+id/ivAvatar"
                app:layout_constraintTop_toTopOf="parent" />


            <TextView
                android:id="@+id/tvDate"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_marginTop="4dp"
                android:textColor="?android:textColorSecondary"
                android:textSize="12sp"
                app:layout_constraintStart_toStartOf="@+id/tvTitle"
                app:layout_constraintTop_toBottomOf="@id/tvTitle"
                tools:text="Tuesday 7pm" />

            <TextView
                android:id="@+id/tvBody"
                android:layout_width="0dp"
                android:layout_height="wrap_content"
                android:layout_marginTop="8dp"
                android:layout_marginEnd="16dp"
                android:ellipsize="end"
                android:lines="1"
                android:text="@string/bacon_ipsum_short"
                android:textSize="16sp"
                app:layout_constraintEnd_toEndOf="parent"
                app:layout_constraintStart_toStartOf="@+id/ivAvatar"
                app:layout_constraintTop_toBottomOf="@id/tvDate" />


            <androidx.recyclerview.widget.RecyclerView
                android:id="@+id/recyclerView"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:layout_marginStart="16dp"
                android:layout_marginTop="16dp"
                android:layout_marginEnd="16dp"
                android:orientation="horizontal"
                android:overScrollMode="never"
                android:visibility="gone"
                app:layoutManager="androidx.recyclerview.widget.LinearLayoutManager"
                app:layout_constraintBottom_toBottomOf="parent"
                app:layout_constraintEnd_toEndOf="parent"
                app:layout_constraintStart_toStartOf="parent"
                app:layout_constraintTop_toBottomOf="@id/tvBody"
                tools:listitem="@layout/item_image_destination" />

        </androidx.constraintlayout.widget.ConstraintLayout>

    </com.google.android.material.card.MaterialCardView>

</layout>

并设置项目的可见性,以折叠或展开

private fun setUpExpandedStatus() {
    if (isExpanded) {
        binding.recyclerView.visibility = View.VISIBLE
        binding.ivExpand.rotationX = 180f
    } else {
        binding.recyclerView.visibility = View.GONE
        binding.ivExpand.rotationX = 0f
    }
}

然后开始过渡

   val transition = TransitionInflater.from(itemView.context)
            .inflateTransition(R.transition.icon_expand_toggle)

  TransitionManager.beginDelayedTransition(parent, transition)

  isExpanded = !isExpanded
        
  setUpExpandedStatus()

我创建了动画和过渡样本,包括gif上的那个,你可以在那里检查它们。

其他回答

好吧,我刚刚发现了一个非常丑陋的解决方案:

public static Animation expand(final View v, Runnable onEnd) {
    try {
        Method m = v.getClass().getDeclaredMethod("onMeasure", int.class, int.class);
        m.setAccessible(true);
        m.invoke(
            v,
            MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED),
            MeasureSpec.makeMeasureSpec(((View)v.getParent()).getMeasuredHeight(), MeasureSpec.AT_MOST)
        );
    } catch (Exception e){
        Log.e("test", "", e);
    }
    final int initialHeight = v.getMeasuredHeight();
    Log.d("test", "initialHeight="+initialHeight);

    v.getLayoutParams().height = 0;
    v.setVisibility(View.VISIBLE);
    Animation a = new Animation()
    {
        @Override
        protected void applyTransformation(float interpolatedTime, Transformation t) {
            final int newHeight = (int)(initialHeight * interpolatedTime);
            v.getLayoutParams().height = newHeight;
            v.requestLayout();
        }

        @Override
        public boolean willChangeBounds() {
            return true;
        }
    };
    a.setDuration(5000);
    v.startAnimation(a);
    return a;
}

请随意提出一个更好的解决方案!

是的,我同意上面的评论。事实上,它似乎是正确的(或者至少是最简单的?)事情要做的是指定(在XML中)一个初始布局高度“0px”——然后你可以传递另一个参数“toHeight”(即“最终高度”)到你的自定义动画子类的构造函数,例如,在上面的例子中,它看起来像这样:

    public DropDownAnim( View v, int toHeight ) { ... }

不管怎样,希望这能有所帮助!:)

你的思路是对的。确保在动画开始之前将v1设置为布局高度为0。在开始动画之前,您需要初始化您的设置,使其看起来像动画的第一帧。

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);
}

这是一个片段,我用来调整一个视图(线性布局)的宽度与动画。

代码应该根据目标大小进行扩展或收缩。如果你想要一个fill_parent宽度,你必须在将标志设置为true时将父类. getmeasuredwidth作为目标宽度。

希望它能帮助到你们中的一些人。

public class WidthResizeAnimation extends Animation {
int targetWidth;
int originaltWidth;
View view;
boolean expand;
int newWidth = 0;
boolean fillParent;

public WidthResizeAnimation(View view, int targetWidth, boolean fillParent) {
    this.view = view;
    this.originaltWidth = this.view.getMeasuredWidth();
    this.targetWidth = targetWidth;
    newWidth = originaltWidth;
    if (originaltWidth > targetWidth) {
        expand = false;
    } else {
        expand = true;
    }
    this.fillParent = fillParent;
}

@Override
protected void applyTransformation(float interpolatedTime, Transformation t) {
    if (expand && newWidth < targetWidth) {
        newWidth = (int) (newWidth + (targetWidth - newWidth) * interpolatedTime);
    }

    if (!expand && newWidth > targetWidth) {
        newWidth = (int) (newWidth - (newWidth - targetWidth) * interpolatedTime);
    }
    if (fillParent && interpolatedTime == 1.0) {
        view.getLayoutParams().width = -1;

    } else {
        view.getLayoutParams().width = newWidth;
    }
    view.requestLayout();
}

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

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

}