如何设置RotateAnimation的半径

Question

我可以对指向屏幕中心的图像进行评分。但它的旋转半径很大，部分遮挡了屏幕。如何设置半径，比如100像素。

    DisplayMetrics displaymetrics = new DisplayMetrics();
    getWindowManager().getDefaultDisplay().getMetrics(displaymetrics);

    screenWidthPixel = displaymetrics.widthPixels;
    screenHeightPixel = displaymetrics.heightPixels;

    center_x = screenWidthPixel/2;
    center_y = screenHeightPixel/2;

    //RotateAnimation rotate = new RotateAnimation(0, 360, Animation.ABSOLUTE, center_x, Animation.ABSOLUTE, center_y);
    RotateAnimation rotate = new RotateAnimation(0, 360, center_x, center_y);
    rotate.setDuration(2000);
    rotate.setRepeatCount(Animation.INFINITE);
    rotate.setInterpolator(new LinearInterpolator());

    ImageView image= (ImageView) findViewById(R.id.test_img);

    image.setAnimation(rotate);

我看起来有点像rotate.setRadius(100)

Answer 1

试试这个：

从RotateAnimation()中删除center_x和center_y参数，在layout.xml中将ImageView设置在屏幕中央。

Activity.java

 RotateAnimation rotate = new RotateAnimation(0, 360);
 rotate.setDuration(2000);
 rotate.setRepeatCount(Animation.INFINITE);
 rotate.setInterpolator(new LinearInterpolator());
 ImageView image= (ImageView) findViewById(R.id.test_img);
 image.setAnimation(rotate);

layout.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    >
    <ImageView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/test_img"
        android:src="@mipmap/ic_launcher"
        android:layout_centerInParent="true"
        />
</RelativeLayout>