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

这是我的解决方案,我的ImageView从100%增长到200%,并返回到原来的大小,使用res/anim/文件夹中的两个动画文件

anim_grow.xml

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android"
 android:interpolator="@android:anim/accelerate_interpolator">
 <scale
  android:fromXScale="1.0"
  android:toXScale="2.0"
  android:fromYScale="1.0"
  android:toYScale="2.0"
  android:duration="3000"
  android:pivotX="50%"
  android:pivotY="50%"
  android:startOffset="2000" />
</set>

anim_shrink.xml

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android"
 android:interpolator="@android:anim/accelerate_interpolator">
 <scale
  android:fromXScale="2.0"
  android:toXScale="1.0"
  android:fromYScale="2.0"
  android:toYScale="1.0"
  android:duration="3000"
  android:pivotX="50%"
  android:pivotY="50%"
  android:startOffset="2000" />
</set>

发送一个ImageView到setAnimationGrowShrink()方法

ImageView img1 = (ImageView)findViewById(R.id.image1);
setAnimationGrowShrink(img1);

setAnimationGrowShrink()方法:

private void setAnimationGrowShrink(final ImageView imgV){
    final Animation animationEnlarge = AnimationUtils.loadAnimation(getApplicationContext(), R.anim.anim_grow);
    final Animation animationShrink = AnimationUtils.loadAnimation(getApplicationContext(), R.anim.anim_shrink);

    imgV.startAnimation(animationEnlarge);

    animationEnlarge.setAnimationListener(new AnimationListener() {         
        @Override
        public void onAnimationStart(Animation animation) {}

        @Override
        public void onAnimationRepeat(Animation animation) {}

        @Override
        public void onAnimationEnd(Animation animation) {
            imgV.startAnimation(animationShrink);
        }
    });

    animationShrink.setAnimationListener(new AnimationListener() {          
        @Override
        public void onAnimationStart(Animation animation) {}

        @Override
        public void onAnimationRepeat(Animation animation) {}

        @Override
        public void onAnimationEnd(Animation animation) {
            imgV.startAnimation(animationEnlarge);
        }
    });

}

其他回答

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。

来自@Tom Esterez和@Geraldo Neto的组合解决方案

public static void expandOrCollapseView(View v,boolean expand){

    if(expand){
        v.measure(ViewGroup.LayoutParams.MATCH_PARENT,ViewGroup.LayoutParams.WRAP_CONTENT);
        final int targetHeight = v.getMeasuredHeight();
        v.getLayoutParams().height = 0;
        v.setVisibility(View.VISIBLE);
        ValueAnimator valueAnimator = ValueAnimator.ofInt(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(500);
        valueAnimator.start();
    }
    else
    {
        final int initialHeight = v.getMeasuredHeight();
        ValueAnimator valueAnimator = ValueAnimator.ofInt(initialHeight,0);
        valueAnimator.setInterpolator(new DecelerateInterpolator());
        valueAnimator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
            @Override
            public void onAnimationUpdate(ValueAnimator animation) {
                v.getLayoutParams().height = (int) animation.getAnimatedValue();
                v.requestLayout();
                if((int)animation.getAnimatedValue() == 0)
                    v.setVisibility(View.GONE);
            }
        });
        valueAnimator.setInterpolator(new DecelerateInterpolator());
        valueAnimator.setDuration(500);
        valueAnimator.start();
    }
}

//sample usage
expandOrCollapseView((Your ViewGroup),(Your ViewGroup).getVisibility()!=View.VISIBLE);

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;
}

}

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)
}

这是一个合适的工作解决方案,我已经测试过了:

例如:

private void expand(View v) {
    v.setVisibility(View.VISIBLE);

    v.measure(View.MeasureSpec.makeMeasureSpec(PARENT_VIEW.getWidth(), View.MeasureSpec.EXACTLY),
            View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED));

    final int targetHeight = v.getMeasuredHeight();

    mAnimator = slideAnimator(0, targetHeight);
    mAnimator.setDuration(800);
    mAnimator.start();
}

崩溃:

private void collapse(View v) {
    int finalHeight = v.getHeight();

    mAnimator = slideAnimator(finalHeight, 0);

    mAnimator.addListener(new Animator.AnimatorListener() {
        @Override
        public void onAnimationStart(Animator animator) {

        }

        @Override
        public void onAnimationEnd(Animator animator) {
            //Height=0, but it set visibility to GONE
            llDescp.setVisibility(View.GONE);
        }

        @Override
        public void onAnimationCancel(Animator animator) {

        }

        @Override
        public void onAnimationRepeat(Animator animator) {

        }
    });
    mAnimator.start();
}

动画师的值:

private ValueAnimator slideAnimator(int start, int end) {
    ValueAnimator mAnimator = ValueAnimator.ofInt(start, end);

    mAnimator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
        @Override
        public void onAnimationUpdate(ValueAnimator valueAnimator) {
            //Update Height
            int value = (Integer) valueAnimator.getAnimatedValue();
            ViewGroup.LayoutParams layoutParams = llDescp.getLayoutParams();
            layoutParams.height = value;
            v.setLayoutParams(layoutParams);
        }
    });
    return mAnimator;
}

视图v是要被动画的视图,PARENT_VIEW是包含该视图的容器视图。