与动画改变布局的重量 [英] Change the weight of layout with an animation

问题描述

在我的主要布局文件，我有一个RelativeLayout的，用的重量1（基本上显示地图）以上的LinearLayout为2的权重，这样声明：

In my main layout file, I have a RelativeLayout, with a weight of 1 (basically to display a map) above a LinearLayout with a weight of 2, declared this way :

<LinearLayout
    android:id="@+id/GlobalLayout"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >

    <RelativeLayout
        android:id="@+id/UpLayout"
        android:layout_width="match_parent"
        android:layout_height="0px"
        android:layout_weight="1" >
    </RelativeLayout>

    <LinearLayout
        android:id="@+id/DownLayout"
        android:layout_width="match_parent"
        android:layout_height="0px"
        android:layout_weight="2"
        android:orientation="vertical" >
    </LinearLayout>

</LinearLayout>

DownLayout包含的项目列表，当我点击一个项目，我想改变DownLayout的权重为4，因此上布局（地图）只需要1/5的画面，而不是1/3

DownLayout contains a list of items, when I click on an item, I would like to change the weight of DownLayout for 4, so the upper layout (the map) takes only 1/5 of the screen instead of 1/3.

我已经成功地做​​到这一点改变的LayoutParams：

I have managed to do it by changing the LayoutParams :

    LinearLayout linearLayout = (LinearLayout) mActivity.findViewById(R.id.DownLayout);
    LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(
            LayoutParams.WRAP_CONTENT, LayoutParams.MATCH_PARENT);
    params.weight = 4.0f;
    linearLayout.setLayoutParams(params);

它的工作原理，但我不太满意，变化太直接，没有过渡，而且我想它是光滑的。有没有办法用动画是什么？

It works but I'm not satisfied, the change is too immediate, there is no transition while I would like it to be smooth. Is there a way to use animation for that ?

我发现ObjectAnimator一些例子来改变weightSum，但并不想得到我想要的（如果我只更改此属性，下面我有我的下布局一些自由空间）：

I found some examples with ObjectAnimator to change the weightSum, but it does not do want I want (if I change only this property, I have some free space below my down layout) :

        float ws = mLinearLayout.getWeightSum();
        ObjectAnimator anim = ObjectAnimator.ofFloat(mLinearLayout, "weightSum", ws, 5.0f);
        anim.setDuration(3000);
        anim.addUpdateListener(this);
        anim.start();

有没有办法使用ObjectAnimator（或别的东西），要做到这一点？

Is there a way to use ObjectAnimator (or something else) to do that ?

谢谢！

推荐答案

我最近碰到一个类似的问题，解决了它使用的是标准的动画（我有目标API 10所以不能使用ObjectAnimator）。我用了答案的组合这里有轻微改动，考虑到权重，而不是高度。

I recently came across a similar problem and solved it using a standard Animation (I have to target API 10 so couldn't use ObjectAnimator). I used a combination of the answer here with slight alterations to take into account weight instead of height.

我的自定义动画类看起来如下...

My custom animation class looks as follows...

private class ExpandAnimation extends Animation {

    private final float mStartWeight;
    private final float mDeltaWeight;

    public ExpandAnimation(float startWeight, float endWeight) {
        mStartWeight = startWeight;
        mDeltaWeight = endWeight - startWeight;
    }

    @Override
    protected void applyTransformation(float interpolatedTime, Transformation t) {
        LinearLayout.LayoutParams lp = (LinearLayout.LayoutParams) mContent.getLayoutParams();
        lp.weight = (mStartWeight + (mDeltaWeight * interpolatedTime));
        mContent.setLayoutParams(lp);
    }

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

和它的调用该方法...

And its called by this method...

public void toggle() {
    Animation a;
    if (mExpanded) {
        a = new ExpandAnimation(mExpandedWeight, mCollapsedWeight);
        mListener.onCollapse(mContent);
    } else {
        a = new ExpandAnimation(mCollapsedWeight, mExpandedWeight);
        mListener.onExpand(mContent);
    }

    a.setDuration(mAnimationDuration);
    mContent.startAnimation(a);
    mExpanded = !mExpanded;
}

希望这会帮助你，如果你需要了解更多信息或有关于什么问题，让我知道。

Hopefully this will help you out, if you need more details or have questions about something let me know.

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