android - 将变形动画从箭头反转为复选标记

Question

我正在尝试实现变形效果，当用户单击 myButton 时，ImageView 中的图像应该从箭头变形为复选标记。当他再次点击它时，过程应该相反:复选标记应该变成箭头。

这是我所做的:

animated_vector.xml:

<?xml version="1.0" encoding="utf-8"?>
<animated-vector xmlns:android="http://schemas.android.com/apk/res/android"
    android:drawable="@drawable/vector_upvote">

    <target
        android:name="rotationGroup"
        android:animation="@anim/rotate_a_to_b" />

    <target
        android:name="upvote"
        android:animation="@animator/animator_upvote_to_checkmark" />
</animated-vector>

animator_upvote_to_checkmark.xml:

<objectAnimator
    android:duration="250"
    android:propertyName="pathData"
    android:valueFrom="@string/svg_upvote"
    android:valueTo="@string/svg_checkmark"
    android:valueType="pathType"
    android:repeatMode="reverse" />

这就是我播放动画的方式:

            Drawable drawable = upVote.getDrawable();
            if (drawable instanceof Animatable) {

                ((Animatable) drawable).start();
            }

这会将箭头变成复选标记，我该如何反转这个过程？

Answer 1

如果您的 View 是 checkable 并且您的 minsdk > 21 您可以尝试将 StateListAnimator 与 AnimatedVectorDrawable 一起使用，但是因为 appcompat 现在支持 vectorDrawable 和 AnimatedVectorDrawable 并且对使用所有 DrawableContainers 也有限制我不接受以上方法。

So let me tell you what may work:

DrawableContainers which reference other drawables resources which contain only a vector resource. For example, a StateListDrawable which references other files which contain a vector.

来自 Chris Banes

为了实现这一点，我将创建自定义 ImageView，每次单击它时，您都必须调用 morph 函数来运行适当的 vectorAnimatorDrawable。

So代码和demo:

public class ArrowToCheckMarkMorphingImageView extends ImageView {

    private AnimatedVectorDrawable mArrowToCheckMark;
    private AnimatedVectorDrawable mCheckMarkToArrow;
    private boolean mIsShowingCheckMark;
    public ArrowToCheckMarkMorphingImageView(Context context) {
        super(context);
        init();
    }

    public ArrowToCheckMarkMorphingImageView(Context context, AttributeSet attrs) {
        super(context, attrs);
        init();
    }

    public ArrowToCheckMarkMorphingImageView(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        init();
    }

    public ArrowToCheckMarkMorphingImageView(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
        super(context, attrs, defStyleAttr, defStyleRes);
        init();
    }

    public void init(){
        mIsShowingCheckMark = false;
        mArrowToCheckMark =
                (AnimatedVectorDrawable)getContext().getDrawable(R.drawable.arrow_to_checkmark);
        mCheckMarkToArrow =
                (AnimatedVectorDrawable)getContext().getDrawable(R.drawable.checkmark_to_arrow);
        setImageDrawable(mArrowToCheckMark);
    }

    public void morph(){
        final AnimatedVectorDrawable drawable
                = mIsShowingCheckMark ? mCheckMarkToArrow : mArrowToCheckMark;
        setImageDrawable(drawable);
        drawable.start();
        mIsShowingCheckMark = !mIsShowingCheckMark;
    }

}

和MainActivity:

public class MainActivity extends AppCompatActivity {

    ArrowToCheckMarkMorphingImageView mArrowToCheckMarkImageView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);
        mArrowToCheckMarkImageView = (ArrowToCheckMarkMorphingImageView)findViewById(R.id.imageView);
        mArrowToCheckMarkImageView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                mArrowToCheckMarkImageView.morph();
            }
        });
    }
}

在布局文件中你必须像这样使用它:

  <yourpackage.ArrowToCheckMarkMorphingImageView
        android:id="@+id/imageView"
        android:layout_width="50dp"
        android:layout_height="50dp"
        android:layout_centerInParent="true"
        />

以及为想要尝试的人提供的资源:

res/animator/arrow_to_checkmark

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android">
    <objectAnimator
        android:duration="500"
        android:propertyName="pathData"
        android:valueFrom="M7.41,15.41 L12,10.83 l4.59,4.58 L18,14 18,14 l-6,-6 -6,6z"
        android:valueTo  ="M9,16.17 L4.83,12 l-1.42,1.41 L9,19 21,7 l-1.41,-1.41 0,0z"
        android:valueType="pathType" />
    <objectAnimator
        android:duration="500"
        android:propertyName="fillColor"
        android:valueFrom="#FF0000FF"
        android:valueTo="#FF00FF00" />
</set>

res/animator/checkmark_to_arrow

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android">
    <objectAnimator
        android:duration="500"
        android:propertyName="pathData"
        android:valueFrom="M9,16.17 L4.83,12 l-1.42,1.41 L9,19 21,7 l-1.41,-1.41 0,0z"
        android:valueTo  ="M7.41,15.41 L12,10.83 l4.59,4.58 L18,14 18,14 l-6,-6 -6,6z"
        android:valueType="pathType" />
    <objectAnimator
        android:duration="500"
        android:propertyName="fillColor"
        android:valueFrom="#FF00FF00"
        android:valueTo="#FF0000FF" />
</set>

res/drawable/arrow_to_checkmark

<?xml version="1.0" encoding="utf-8"?>
<animated-vector xmlns:android="http://schemas.android.com/apk/res/android"
    android:drawable="@drawable/ic_arrow_up_24dp">
    <target
        android:animation="@animator/arrow_to_checkmark"
        android:name="arrow"/>
</animated-vector>

res/drawable/checkmark_to_arrow

<?xml version="1.0" encoding="utf-8"?>
<animated-vector xmlns:android="http://schemas.android.com/apk/res/android"
    android:drawable="@drawable/ic_checkmark_24dp">
    <target
        android:animation="@animator/checkmark_to_arrow"
        android:name="checkmark"/>
</animated-vector>

res/drawable/ic_arrow_up_24dp

<vector xmlns:android="http://schemas.android.com/apk/res/android"
        android:width="24dp"
        android:height="24dp"
        android:viewportWidth="24.0"
        android:viewportHeight="24.0">
    <path
        android:name="arrow"
        android:fillColor="#FF0000FF"
        android:pathData="M7.41,15.41 L12,10.83 l4.59,4.58 L18,14 18,14 l-6,-6 -6,6z"/>
</vector>

res/drawable/ic_checkmark_24dp

<vector xmlns:android="http://schemas.android.com/apk/res/android"
        android:width="24dp"
        android:height="24dp"
        android:viewportWidth="24.0"
        android:viewportHeight="24.0">
    <path
        android:name="checkmark"
        android:fillColor="#FF00FF00"
        android:pathData="M9,16.17 L4.83,12 l-1.42,1.41 L9,19 21,7 l-1.41,-1.41 0,0z"/>
</vector>