最佳解决方案https://www.youtube.com/watch?v=0MHoNU7ytaw 卡视图的宽度和高度决定了它所包含图像的大小设置如下:

向Gradle添加依赖项(模块) 将xml代码添加到activity.xml或fragment.xml文件中

    implementation 'androidx.cardview:cardview:1.0.0'

   <androidx.cardview.widget.CardView
      android:layout_width="300dp"
      android:layout_height="270dp"
      android:layout_gravity="center"
      app:cardCornerRadius="150dp"
      app:cardBackgroundColor="@color/trans"
      >
    <ImageView
        android:id="@+id/resultImage"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:src="@drawable/congrats"
        android:layout_gravity="center">

    </ImageView>


  </androidx.cardview.widget.CardView>```

创建一个CustomImageview，然后简单地覆盖它的onDraw()方法如下:

@Override
protected void onDraw(Canvas canvas) {

    float radius = this.getHeight()/2;
    Path path = new Path();
    RectF rect = new RectF(0, 0, this.getWidth(), this.getHeight());
    path.addRoundRect(rect, radius, radius, Path.Direction.CW);
    canvas.clipPath(path);
    super.onDraw(canvas);

}

如果你想要的代码自定义小部件以及:-

CircularImageView.java

import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Canvas;
import android.graphics.Path;
import android.graphics.RectF;
import android.graphics.drawable.Drawable;
import android.util.AttributeSet;
import android.widget.ImageView;

import androidx.annotation.Nullable;

public class CircularImageView extends ImageView {

    private Drawable image;

    public CircularImageView(Context context) {
        super(context);

        init(null, 0);
    }

    public CircularImageView(Context context, @Nullable AttributeSet attrs) {
        super(context, attrs);

        init(attrs, 0);
    }

    public CircularImageView(Context context, @Nullable AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);

        init(attrs, defStyleAttr);
    }

    @Override
    protected void onDraw(Canvas canvas) {

        float radius = this.getHeight()/2;
        Path path = new Path();
        RectF rect = new RectF(0, 0, this.getWidth(), this.getHeight());
        path.addRoundRect(rect, radius, radius, Path.Direction.CW);
        canvas.clipPath(path);
        super.onDraw(canvas);

    }

    private void init(AttributeSet attrs, int defStyle) {
        TypedArray a = Utils.CONTEXT.getTheme().obtainStyledAttributes(attrs, R.styleable.CircularImageView, 0, 0);
        try {
            image = a.getDrawable(R.styleable.CircularImageView_src);
        } finally {
            a.recycle();
        }

        this.setImageDrawable(image);
    }
}

此外，在res/attrs.xml中添加以下代码来创建所需的属性

<declare-styleable name="CircularImageView">
        <attr name="src" format="reference" />
</declare-styleable>

如果使用src属性，上述方法似乎不起作用。我所做的是把两个图像视图放在一个框架布局中，一个在另一个上面，就像这样:

<FrameLayout android:id="@+id/frame"
             android:layout_width="40dp"
             android:layout_height="40dp">

    <ImageView android:id="@+id/pic"
               android:layout_width="40dp"
               android:layout_height="40dp"
               android:src="@drawable/my_picture" />

    <ImageView android:id="@+id/circle_crop"
               android:layout_width="40dp"
               android:layout_height="40dp"
               android:src="@drawable/circle_crop" />

</FrameLayout>

简单地把一个circular_crop.png放在你的可绘制文件夹中，它是你的图像尺寸的形状(在我的例子中是一个正方形)，白色背景，中间是一个透明的圆。如果你想要一个正方形imageview，你可以使用这个图像。

下载上面的图片。

if you want to set edit icon on to circle imageview than put this below code.

 <FrameLayout
                android:layout_width="@dimen/_100sdp"
                android:layout_height="@dimen/_100sdp"
                android:layout_gravity="center"
                android:layout_marginTop="10dp">

                <de.hdodenhof.circleimageview.CircleImageView
                    android:id="@+id/profilePic"
                    android:layout_width="@dimen/_100sdp"
                    android:layout_height="@dimen/_100sdp"
                    android:layout_gravity="bottom|center_horizontal"
                    android:src="@drawable/ic_upload" />

                <de.hdodenhof.circleimageview.CircleImageView
                    android:id="@+id/iv_camera"
                    android:layout_width="@dimen/_30sdp"
                    android:layout_height="@dimen/_30sdp"
                    android:layout_gravity="top|right"
                    android:src="@drawable/edit"/>
            </FrameLayout>

如果您希望将图像切割成圆形显示，可以这样做

public static Bitmap getCircularBitmap(Bitmap bitmap) {
        Bitmap output;

        if (bitmap.getWidth() > bitmap.getHeight()) {
            output = Bitmap.createBitmap(bitmap.getHeight(), bitmap.getHeight(), Bitmap.Config.ARGB_8888);
        } else {
            output = Bitmap.createBitmap(bitmap.getWidth(), bitmap.getWidth(), Bitmap.Config.ARGB_8888);
        }

        Canvas canvas = new Canvas(output);

        final int color = 0xff424242;
        final Paint paint = new Paint();
        final Rect rect = new Rect(0, 0, bitmap.getWidth(), bitmap.getHeight());

        float r = 0;

        if (bitmap.getWidth() > bitmap.getHeight()) {
            r = bitmap.getHeight() / 2;
        } else {
            r = bitmap.getWidth() / 2;
        }

        paint.setAntiAlias(true);
        canvas.drawARGB(0, 0, 0, 0);
        paint.setColor(color);
        canvas.drawCircle(r, r, r, paint);
        paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_IN));
        canvas.drawBitmap(bitmap, rect, rect, paint);
        return output;
    }

在glide库和RoundedBitmapDrawableFactory类的帮助下，很容易实现。您可能需要创建圆形占位符映像。

滑翔V4:

Glide.with(context).load(url).apply(RequestOptions.circleCropTransform()).into(imageView);

滑翔V3:

    Glide.with(context)
        .load(imgUrl)
        .asBitmap()
        .placeholder(R.drawable.placeholder)
        .error(R.drawable.placeholder)
        .into(new BitmapImageViewTarget(imgProfilePicture) {
            @Override
            protected void setResource(Bitmap resource) {
                RoundedBitmapDrawable drawable = RoundedBitmapDrawableFactory.create(context.getResources(),
                        Bitmap.createScaledBitmap(resource, 50, 50, false));
                drawable.setCircular(true);
                imgProfilePicture.setImageDrawable(drawable);
            }
        });

对于Picasso RoundedTransformation，这是一个非常好的解决方案，提供了一个额外的选择，在顶部或底部边缘的图像。