试试这个。

public class RoundedImageView extends android.support.v7.widget.AppCompatImageView {

    private int borderWidth = 4;
    private int viewWidth;
    private int viewHeight;
    private Bitmap image;
    private Paint paint;
    private Paint paintBorder;
    private BitmapShader shader;

    public RoundedImageView(Context context)
    {
        super(context);
        setup();
    }

    public RoundedImageView(Context context, AttributeSet attrs)
    {
        super(context, attrs);
        setup();
    }

    public RoundedImageView(Context context, AttributeSet attrs, int defStyle)
    {
        super(context, attrs, defStyle);
        setup();
    }

    private void setup()
    {
        paint = new Paint();
        paint.setAntiAlias(true);

        paintBorder = new Paint();
        setBorderColor(Color.WHITE);
        paintBorder.setAntiAlias(true);
        this.setLayerType(LAYER_TYPE_SOFTWARE, paintBorder);

        paintBorder.setShadowLayer(4.0f, 0.0f, 2.0f, Color.WHITE);
    }

    public void setBorderWidth(int borderWidth)
    {
        this.borderWidth = borderWidth;
        this.invalidate();
    }

    public void setBorderColor(int borderColor)
    {
        if (paintBorder != null)
            paintBorder.setColor(borderColor);

        this.invalidate();
    }

    private void loadBitmap()
    {
        BitmapDrawable bitmapDrawable = (BitmapDrawable) this.getDrawable();

        if (bitmapDrawable != null)
            image = bitmapDrawable.getBitmap();
    }

    @SuppressLint("DrawAllocation")
    @Override
    public void onDraw(Canvas canvas)
    {
        loadBitmap();

        if (image != null)
        {
            shader = new BitmapShader(Bitmap.createScaledBitmap(image, canvas.getWidth(), canvas.getHeight(), false), Shader.TileMode.CLAMP, Shader.TileMode.CLAMP);
            paint.setShader(shader);
            int circleCenter = viewWidth / 2;
            canvas.drawCircle(circleCenter + borderWidth, circleCenter + borderWidth, circleCenter + borderWidth - 4.0f, paintBorder);
            canvas.drawCircle(circleCenter + borderWidth, circleCenter + borderWidth, circleCenter - 4.0f, paint);
        }
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec)
    {
        int width = measureWidth(widthMeasureSpec);
        int height = measureHeight(heightMeasureSpec, widthMeasureSpec);

        viewWidth = width - (borderWidth * 2);
        viewHeight = height - (borderWidth * 2);

        setMeasuredDimension(width, height);
    }

    private int measureWidth(int measureSpec)
    {
        int result = 0;
        int specMode = MeasureSpec.getMode(measureSpec);
        int specSize = MeasureSpec.getSize(measureSpec);

        if (specMode == MeasureSpec.EXACTLY)
        {
            result = specSize;
        }
        else
        {
            // Measure the text
            result = viewWidth;
        }

        return result;
    }

    private int measureHeight(int measureSpecHeight, int measureSpecWidth)
    {
        int result = 0;
        int specMode = MeasureSpec.getMode(measureSpecHeight);
        int specSize = MeasureSpec.getSize(measureSpecHeight);

        if (specMode == MeasureSpec.EXACTLY)
        {
            result = specSize;
        }
        else
        {
            result = viewHeight;
        }

        return (result + 2);
     }
 }

然后在布局中使用这个ImageView:

<com.app.Demo.RoundedImageView
     android:id="@+id/iv_profileImage"
     android:layout_width="70dp"
     android:layout_height="70dp"
     android:layout_centerHorizontal="true"
    />

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。

这是一个相对较老的问题，但您可以在可绘制文件夹中创建一个圆形边框(假设xml文件将称为circle_border)

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns="http://schemas.android.com/apk/res/android"
    android:shape="oval">

    <solid android:color="@android:color/transparent" />

    <!-- If you want a padding -->
    <padding android:top="4dp" android:left="4dp" android:right="4dp" android:bottom="4dp" />

    <!-- If you want the circle border to have a color -->
    <strong android:width="1dp" android:color="#FFFFFF" />

</shape>

然后你可以使用它作为ImageView的背景

<ImageView
    android:background="@drawable/circle_border"
    <!-- other attributes here -->
/>

另一种不使用任何库的方法是使用ImageFilterView，并设置视图的圆百分比将使圆

app: roundPercent =“1”

  <androidx.constraintlayout.utils.widget.ImageFilterView
        android:id="@+id/ivProfile"
        android:layout_width="150dp"
        android:layout_height="150dp"
        android:src="@drawable/custom_button_1"
        app:roundPercent="1"
        android:scaleType="fitXY"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintBottom_toTopOf="@+id/etName"/>

2021年更新:使用Glide v4 CircleCrop参见https://bumptech.github.io/glide/doc/generatedapi.html

    implementation 'com.github.bumptech.glide:glide:4.11.0'
    annotationProcessor 'com.github.bumptech.glide:compiler:4.11.0'

XML

<ImageView
    android:id="@+id/vinyl"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:ignore="ContentDescription" />

在代码中

    Glide.with(this)
            .load("https://images.pexels.com/photos/3828241/pexels-photo-3828241.jpeg")
            .transform(CircleCrop())
            .into(rootView.findViewById<ImageView>(R.id.vinyl))

使用材质组件库只需使用ShapeableImageView。 Somethig:

<com.google.android.material.imageview.ShapeableImageView
    app:shapeAppearanceOverlay="@style/roundedImageViewRounded"
    app:strokeColor="@color/....."
    app:strokeWidth="1dp"
    ...
    />

:

  <style name="roundedImageViewRounded">
    <item name="cornerFamily">rounded</item>
    <item name="cornerSize">50%</item>
  </style>

注意:它至少需要1.2.0版本。

使用jetpack合成，你可以使用CircleShape应用剪辑修饰器:

Image(
    painter = painterResource(R.drawable.xxxx),
    contentDescription = "xxxx",
    contentScale = ContentScale.Crop,
    modifier = Modifier
        .size(100.dp)
        .clip(CircleShape)
        .border(2.dp, Color.Blue, CircleShape)
)