只有一个圆角的ImageView

Question

我正在尝试制作 ImageView 的一个圆角，如下图所示，但右下角。尝试使用背景形状，但它根本不起作用。 Glide 加载的所有图像。我应该使用 ViewOutlineProvider 之类的东西吗？有没有一种有效的方法来做到这一点？谢谢！

<shape xmlns:android="http://schemas.android.com/apk/res/android" >
    <corners
        android:radius="2dp"
        android:bottomRightRadius="20dp"
        android:bottomLeftRadius="0dp"
        android:topLeftRadius="0dp"
        android:topRightRadius="0dp"/>
</shape>

Answer 1

这是您的主要布局文件，它使用自定义可绘制文件 "round_one.xml"文件。只需复制并粘贴此代码。希望它能满足您的要求。

<?xml version="1.0" encoding="utf-8"?>
<androidx.cardview.widget.CardView xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:elevation="@dimen/_10sdp"
    android:background="@color/white"
    android:orientation="vertical" android:layout_width="match_parent"
    android:layout_height="wrap_content">

    <LinearLayout
        android:id="@+id/linearLayout2"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="@drawable/round_one"
        android:orientation="vertical"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent">

        <ImageView
            android:layout_width="match_parent"
            android:layout_height="@dimen/_80sdp"
            android:layout_gravity="center"
            android:scaleType="fitXY"
            android:src="@android:drawable/ic_menu_day" />
        <TextView
            android:id="@+id/textView22"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginStart="16dp"
            android:layout_marginTop="16dp"
            android:layout_marginEnd="8dp"
            android:text="title goes here" />

        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginStart="16dp"
            android:layout_marginTop="8dp"
            android:layout_marginBottom="8dp"
            android:text="Secondary text"
            />
    </LinearLayout>


</androidx.cardview.widget.CardView>

round_one.xml

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android">
    <solid android:color="@color/gray" />
    <corners android:topRightRadius="50dp" />
</shape>

Answer 2

要仅将 imageview 的一个角倒圆，请按照以下步骤和代码进行操作：

将以下文件添加到您的项目中RoundCornerImageView.java

package com.skd.stackdemo;

import android.annotation.SuppressLint;
import android.content.Context;
import android.content.res.ColorStateList;
import android.content.res.Resources;
import android.content.res.TypedArray;
import android.graphics.Bitmap;
import android.graphics.BitmapShader;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.ColorFilter;
import android.graphics.Matrix;
import android.graphics.Paint;
import android.graphics.Path;
import android.graphics.PixelFormat;
import android.graphics.Rect;
import android.graphics.RectF;
import android.graphics.Shader;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;
import android.graphics.drawable.LayerDrawable;
import android.net.Uri;
import android.util.AttributeSet;
import android.util.Log;
import android.widget.ImageView;

public class RoundCornerImageView extends ImageView {

    public static final String TAG = "RoundCornerImageView";

    private int mResource = 0;

    private static final ScaleType[] sScaleTypeArray = {
            ScaleType.MATRIX,
            ScaleType.FIT_XY,
            ScaleType.FIT_START,
            ScaleType.FIT_CENTER,
            ScaleType.FIT_END,
            ScaleType.CENTER,
            ScaleType.CENTER_CROP,
            ScaleType.CENTER_INSIDE
    };

    // Set default scale type to FIT_CENTER, which is default scale type of
    // original ImageView.
    private ScaleType mScaleType = ScaleType.FIT_CENTER;

    private float mLeftTopCornerRadius = 0.0f;
    private float mRightTopCornerRadius = 0.0f;
    private float mLeftBottomCornerRadius = 0.0f;
    private float mRightBottomCornerRadius = 0.0f;

    private float mBorderWidth = 0.0f;
    private static final int DEFAULT_BORDER_COLOR = Color.BLACK;
    private ColorStateList mBorderColor = ColorStateList.valueOf(DEFAULT_BORDER_COLOR);

    private boolean isOval = false;

    private Drawable mDrawable;

    private float[] mRadii = new float[] { 0, 0, 0, 0, 0, 0, 0, 0 };

    public RoundCornerImageView(Context context) {
        super(context);
    }

    public RoundCornerImageView(Context context, AttributeSet attrs) {
        this(context, attrs, 0);
    }

    public RoundCornerImageView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);

        TypedArray a = context.obtainStyledAttributes(attrs,
                R.styleable.SelectableRoundedImageView, defStyle, 0);

        final int index = a.getInt(R.styleable.SelectableRoundedImageView_android_scaleType, -1);
        if (index >= 0) {
            setScaleType(sScaleTypeArray[index]);
        }

        mLeftTopCornerRadius = a.getDimensionPixelSize(
                R.styleable.SelectableRoundedImageView_sriv_left_top_corner_radius, 0);
        mRightTopCornerRadius = a.getDimensionPixelSize(
                R.styleable.SelectableRoundedImageView_sriv_right_top_corner_radius, 0);
        mLeftBottomCornerRadius = a.getDimensionPixelSize(
                R.styleable.SelectableRoundedImageView_sriv_left_bottom_corner_radius, 0);
        mRightBottomCornerRadius = a.getDimensionPixelSize(
                R.styleable.SelectableRoundedImageView_sriv_right_bottom_corner_radius, 0);

        if (mLeftTopCornerRadius < 0.0f || mRightTopCornerRadius < 0.0f
                || mLeftBottomCornerRadius < 0.0f || mRightBottomCornerRadius < 0.0f) {
            throw new IllegalArgumentException("radius values cannot be negative.");
        }

        mRadii = new float[] {
                mLeftTopCornerRadius, mLeftTopCornerRadius,
                mRightTopCornerRadius, mRightTopCornerRadius,
                mRightBottomCornerRadius, mRightBottomCornerRadius,
                mLeftBottomCornerRadius, mLeftBottomCornerRadius };

        mBorderWidth = a.getDimensionPixelSize(
                R.styleable.SelectableRoundedImageView_sriv_border_width, 0);
        if (mBorderWidth < 0) {
            throw new IllegalArgumentException("border width cannot be negative.");
        }

        mBorderColor = a
                .getColorStateList(R.styleable.SelectableRoundedImageView_sriv_border_color);
        if (mBorderColor == null) {
            mBorderColor = ColorStateList.valueOf(DEFAULT_BORDER_COLOR);
        }

        isOval = a.getBoolean(R.styleable.SelectableRoundedImageView_sriv_oval, false);
        a.recycle();

        updateDrawable();
    }

    @Override
    protected void drawableStateChanged() {
        super.drawableStateChanged();
        invalidate();
    }

    @Override
    public ScaleType getScaleType() {
        return mScaleType;
    }

    @Override
    public void setScaleType(ScaleType scaleType) {
        super.setScaleType(scaleType);
        mScaleType = scaleType;
        updateDrawable();
    }

    @Override
    public void setImageDrawable(Drawable drawable) {
        mResource = 0;
        mDrawable = RoundCornerDrawable.fromDrawable(drawable, getResources());
        super.setImageDrawable(mDrawable);
        updateDrawable();
    }

    @Override
    public void setImageBitmap(Bitmap bm) {
        mResource = 0;
        mDrawable = RoundCornerDrawable.fromBitmap(bm, getResources());
        super.setImageDrawable(mDrawable);
        updateDrawable();
    }

    @Override
    public void setImageResource(int resId) {
        if (mResource != resId) {
            mResource = resId;
            mDrawable = resolveResource();
            super.setImageDrawable(mDrawable);
            updateDrawable();
        }
    }

    @Override
    public void setImageURI(Uri uri) {
        super.setImageURI(uri);
        setImageDrawable(getDrawable());
    }

    private Drawable resolveResource() {
        Resources rsrc = getResources();
        if (rsrc == null) {
            return null;
        }

        Drawable d = null;

        if (mResource != 0) {
            try {
                d = rsrc.getDrawable(mResource);
            } catch (Resources.NotFoundException e) {
                Log.w(TAG, "Unable to find resource: " + mResource, e);
                // Don't try again.
                mResource = 0;
            }
        }
        return RoundCornerDrawable.fromDrawable(d, getResources());
    }

    private void updateDrawable() {
        if (mDrawable == null) {
            return;
        }

        ((RoundCornerDrawable) mDrawable).setScaleType(mScaleType);
        ((RoundCornerDrawable) mDrawable).setCornerRadii(mRadii);
        ((RoundCornerDrawable) mDrawable).setBorderWidth(mBorderWidth);
        ((RoundCornerDrawable) mDrawable).setBorderColor(mBorderColor);
        ((RoundCornerDrawable) mDrawable).setOval(isOval);
    }

    public float getCornerRadius() {
        return mLeftTopCornerRadius;
    }

    /**
     * Set radii for each corner.
     *
     * @param leftTop The desired radius for left-top corner in dip.
     * @param rightTop The desired desired radius for right-top corner in dip.
     * @param leftBottom The desired radius for left-bottom corner in dip.
     * @param rightBottom The desired radius for right-bottom corner in dip.
     *
     */
    public void setCornerRadiiDP(float leftTop, float rightTop, float leftBottom, float rightBottom) {
        final float density = getResources().getDisplayMetrics().density;

        final float lt = leftTop * density;
        final float rt = rightTop * density;
        final float lb = leftBottom * density;
        final float rb = rightBottom * density;

        mRadii = new float[] { lt, lt, rt, rt, rb, rb, lb, lb };
        updateDrawable();
    }

    public float getBorderWidth() {
        return mBorderWidth;
    }

    /**
     * Set border width.
     *
     * @param width
     *            The desired width in dip.
     */
    public void setBorderWidthDP(float width) {
        float scaledWidth = getResources().getDisplayMetrics().density * width;
        if (mBorderWidth == scaledWidth) {
            return;
        }

        mBorderWidth = scaledWidth;
        updateDrawable();
        invalidate();
    }

    public int getBorderColor() {
        return mBorderColor.getDefaultColor();
    }

    public void setBorderColor(int color) {
        setBorderColor(ColorStateList.valueOf(color));
    }

    public ColorStateList getBorderColors() {
        return mBorderColor;
    }

    public void setBorderColor(ColorStateList colors) {
        if (mBorderColor.equals(colors)) {
            return;
        }

        mBorderColor = (colors != null) ? colors : ColorStateList
                .valueOf(DEFAULT_BORDER_COLOR);
        updateDrawable();
        if (mBorderWidth > 0) {
            invalidate();
        }
    }

    public boolean isOval() {
        return isOval;
    }

    public void setOval(boolean oval) {
        isOval = oval;
        updateDrawable();
        invalidate();
    }

    static class RoundCornerDrawable extends Drawable {

        private static final String TAG = "RoundCornerDrawable";
        private static final int DEFAULT_BORDER_COLOR = Color.BLACK;

        private RectF mBounds = new RectF();
        private RectF mBorderBounds = new RectF();

        private final RectF mBitmapRect = new RectF();
        private final int mBitmapWidth;
        private final int mBitmapHeight;

        private final Paint mBitmapPaint;
        private final Paint mBorderPaint;

        private BitmapShader mBitmapShader;

        private float[] mRadii = new float[] { 0, 0, 0, 0, 0, 0, 0, 0 };
        private float[] mBorderRadii = new float[] { 0, 0, 0, 0, 0, 0, 0, 0 };

        private boolean mOval = false;

        private float mBorderWidth = 0;
        private ColorStateList mBorderColor = ColorStateList.valueOf(DEFAULT_BORDER_COLOR);
        // Set default scale type to FIT_CENTER, which is default scale type of
        // original ImageView.
        private ScaleType mScaleType = ScaleType.FIT_CENTER;

        private Path mPath = new Path();
        private Bitmap mBitmap;
        private boolean mBoundsConfigured = false;

        public RoundCornerDrawable(Bitmap bitmap, Resources r) {
            mBitmap = bitmap;
            mBitmapShader = new BitmapShader(bitmap, Shader.TileMode.CLAMP, Shader.TileMode.CLAMP);

            if (bitmap != null) {
                mBitmapWidth = bitmap.getScaledWidth(r.getDisplayMetrics());
                mBitmapHeight = bitmap.getScaledHeight(r.getDisplayMetrics());
            } else {
                mBitmapWidth = mBitmapHeight = -1;
            }

            mBitmapRect.set(0, 0, mBitmapWidth, mBitmapHeight);

            mBitmapPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
            mBitmapPaint.setStyle(Paint.Style.FILL);
            mBitmapPaint.setShader(mBitmapShader);

            mBorderPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
            mBorderPaint.setStyle(Paint.Style.STROKE);
            mBorderPaint.setColor(mBorderColor.getColorForState(getState(), DEFAULT_BORDER_COLOR));
            mBorderPaint.setStrokeWidth(mBorderWidth);
        }

        public static RoundCornerDrawable fromBitmap(Bitmap bitmap, Resources r) {
            if (bitmap != null) {
                return new RoundCornerDrawable(bitmap, r);
            } else {
                return null;
            }
        }

        @SuppressLint("LongLogTag")
        public static Drawable fromDrawable(Drawable drawable, Resources r) {
            if (drawable != null) {
                if (drawable instanceof RoundCornerDrawable) {
                    return drawable;
                } else if (drawable instanceof LayerDrawable) {
                    LayerDrawable ld = (LayerDrawable) drawable;
                    final int num = ld.getNumberOfLayers();
                    for (int i = 0; i < num; i++) {
                        Drawable d = ld.getDrawable(i);
                        ld.setDrawableByLayerId(ld.getId(i), fromDrawable(d, r));
                    }
                    return ld;
                }

                Bitmap bm = drawableToBitmap(drawable);
                if (bm != null) {
                    return new RoundCornerDrawable(bm, r);
                } else {
                    Log.w(TAG, "Failed to create bitmap from drawable!");
                }
            }
            return drawable;
        }

        public static Bitmap drawableToBitmap(Drawable drawable) {
            if (drawable == null) {
                return null;
            }

            if (drawable instanceof BitmapDrawable) {
                return ((BitmapDrawable) drawable).getBitmap();
            }

            Bitmap bitmap;
            int width = Math.max(drawable.getIntrinsicWidth(), 2);
            int height = Math.max(drawable.getIntrinsicHeight(), 2);
            try {
                bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
                Canvas canvas = new Canvas(bitmap);
                drawable.setBounds(0, 0, canvas.getWidth(), canvas.getHeight());
                drawable.draw(canvas);
            } catch (IllegalArgumentException e) {
                e.printStackTrace();
                bitmap = null;
            }
            return bitmap;
        }

        @Override
        public boolean isStateful() {
            return mBorderColor.isStateful();
        }

        @Override
        protected boolean onStateChange(int[] state) {
            int newColor = mBorderColor.getColorForState(state, 0);
            if (mBorderPaint.getColor() != newColor) {
                mBorderPaint.setColor(newColor);
                return true;
            } else {
                return super.onStateChange(state);
            }
        }

        private void configureBounds(Canvas canvas) {
            // I have discovered a truly marvelous explanation of this,
            // which this comment space is too narrow to contain. :)
            // If you want to understand what's going on here,
            // See http://www.joooooooooonhokim.com/?p=289
            Rect clipBounds = canvas.getClipBounds();
            Matrix canvasMatrix = canvas.getMatrix();

            if (ScaleType.CENTER == mScaleType) {
                mBounds.set(clipBounds);
            } else if (ScaleType.CENTER_CROP == mScaleType) {
                applyScaleToRadii(canvasMatrix);
                mBounds.set(clipBounds);
            } else if (ScaleType.FIT_XY == mScaleType) {
                Matrix m = new Matrix();
                m.setRectToRect(mBitmapRect, new RectF(clipBounds), Matrix.ScaleToFit.FILL);
                mBitmapShader.setLocalMatrix(m);
                mBounds.set(clipBounds);
            } else if (ScaleType.FIT_START == mScaleType || ScaleType.FIT_END == mScaleType
                    || ScaleType.FIT_CENTER == mScaleType || ScaleType.CENTER_INSIDE == mScaleType) {
                applyScaleToRadii(canvasMatrix);
                mBounds.set(mBitmapRect);
            } else if (ScaleType.MATRIX == mScaleType) {
                applyScaleToRadii(canvasMatrix);
                mBounds.set(mBitmapRect);
            }
        }

        private void applyScaleToRadii(Matrix m) {
            float[] values = new float[9];
            m.getValues(values);
            for (int i = 0; i < mRadii.length; i++) {
                mRadii[i] = mRadii[i] / values[0];
            }
        }

        private void adjustCanvasForBorder(Canvas canvas) {
            Matrix canvasMatrix = canvas.getMatrix();
            final float[] values = new float[9];
            canvasMatrix.getValues(values);

            final float scaleFactorX = values[0];
            final float scaleFactorY = values[4];
            final float translateX = values[2];
            final float translateY = values[5];

            final float newScaleX = mBounds.width()
                    / (mBounds.width() + mBorderWidth + mBorderWidth);
            final float newScaleY = mBounds.height()
                    / (mBounds.height() + mBorderWidth + mBorderWidth);

            canvas.scale(newScaleX, newScaleY);
            if (ScaleType.FIT_START == mScaleType || ScaleType.FIT_END == mScaleType
                    || ScaleType.FIT_XY == mScaleType || ScaleType.FIT_CENTER == mScaleType
                    || ScaleType.CENTER_INSIDE == mScaleType || ScaleType.MATRIX == mScaleType) {
                canvas.translate(mBorderWidth, mBorderWidth);
            } else if (ScaleType.CENTER == mScaleType || ScaleType.CENTER_CROP == mScaleType) {
                // First, make translate values to 0
                canvas.translate(
                        -translateX / (newScaleX * scaleFactorX),
                        -translateY / (newScaleY * scaleFactorY));
                // Then, set the final translate values.
                canvas.translate(-(mBounds.left - mBorderWidth), -(mBounds.top - mBorderWidth));
            }
        }

        private void adjustBorderWidthAndBorderBounds(Canvas canvas) {
            Matrix canvasMatrix = canvas.getMatrix();
            final float[] values = new float[9];
            canvasMatrix.getValues(values);

            final float scaleFactor = values[0];

            float viewWidth = mBounds.width() * scaleFactor;
            mBorderWidth = (mBorderWidth * mBounds.width()) / (viewWidth - (2 * mBorderWidth));
            mBorderPaint.setStrokeWidth(mBorderWidth);

            mBorderBounds.set(mBounds);
            mBorderBounds.inset(- mBorderWidth / 2, - mBorderWidth / 2);
        }

        private void setBorderRadii() {
            for (int i = 0; i < mRadii.length; i++) {
                if (mRadii[i] > 0) {
                    mBorderRadii[i] = mRadii[i];
                    mRadii[i] = mRadii[i] - mBorderWidth;
                }
            }
        }

        @Override
        public void draw(Canvas canvas) {
            canvas.save();
            if (!mBoundsConfigured) {
                configureBounds(canvas);
                if (mBorderWidth > 0) {
                    adjustBorderWidthAndBorderBounds(canvas);
                    setBorderRadii();
                }
                mBoundsConfigured = true;
            }

            if (mOval) {
                if (mBorderWidth > 0) {
                    adjustCanvasForBorder(canvas);
                    mPath.addOval(mBounds, Path.Direction.CW);
                    canvas.drawPath(mPath, mBitmapPaint);
                    mPath.reset();
                    mPath.addOval(mBorderBounds, Path.Direction.CW);
                    canvas.drawPath(mPath, mBorderPaint);
                } else {
                    mPath.addOval(mBounds, Path.Direction.CW);
                    canvas.drawPath(mPath, mBitmapPaint);
                }
            } else {
                if (mBorderWidth > 0) {
                    adjustCanvasForBorder(canvas);
                    mPath.addRoundRect(mBounds, mRadii, Path.Direction.CW);
                    canvas.drawPath(mPath, mBitmapPaint);
                    mPath.reset();
                    mPath.addRoundRect(mBorderBounds, mBorderRadii, Path.Direction.CW);
                    canvas.drawPath(mPath, mBorderPaint);
                } else {
                    mPath.addRoundRect(mBounds, mRadii, Path.Direction.CW);
                    canvas.drawPath(mPath, mBitmapPaint);
                }
            }
            canvas.restore();
        }

        public void setCornerRadii(float[] radii) {
            if (radii == null)
                return;

            if (radii.length != 8) {
                throw new ArrayIndexOutOfBoundsException("radii[] needs 8 values");
            }

            for (int i = 0; i < radii.length; i++) {
                mRadii[i] = radii[i];
            }
        }

        @Override
        public int getOpacity() {
            return (mBitmap == null || mBitmap.hasAlpha() || mBitmapPaint.getAlpha() < 255) ? PixelFormat.TRANSLUCENT
                    : PixelFormat.OPAQUE;
        }

        @Override
        public void setAlpha(int alpha) {
            mBitmapPaint.setAlpha(alpha);
            invalidateSelf();
        }

        @Override
        public void setColorFilter(ColorFilter cf) {
            mBitmapPaint.setColorFilter(cf);
            invalidateSelf();
        }

        @Override
        public void setDither(boolean dither) {
            mBitmapPaint.setDither(dither);
            invalidateSelf();
        }

        @Override
        public void setFilterBitmap(boolean filter) {
            mBitmapPaint.setFilterBitmap(filter);
            invalidateSelf();
        }

        @Override
        public int getIntrinsicWidth() {
            return mBitmapWidth;
        }

        @Override
        public int getIntrinsicHeight() {
            return mBitmapHeight;
        }

        public float getBorderWidth() {
            return mBorderWidth;
        }

        public void setBorderWidth(float width) {
            mBorderWidth = width;
            mBorderPaint.setStrokeWidth(width);
        }

        public int getBorderColor() {
            return mBorderColor.getDefaultColor();
        }

        public void setBorderColor(int color) {
            setBorderColor(ColorStateList.valueOf(color));
        }

        public ColorStateList getBorderColors() {
            return mBorderColor;
        }

        /**
         * Controls border color of this ImageView.
         *
         * @param colors
         *            The desired border color. If it's null, no border will be
         *            drawn.
         *
         */
        public void setBorderColor(ColorStateList colors) {
            if (colors == null) {
                mBorderWidth = 0;
                mBorderColor = ColorStateList.valueOf(Color.TRANSPARENT);
                mBorderPaint.setColor(Color.TRANSPARENT);
            } else {
                mBorderColor = colors;
                mBorderPaint.setColor(mBorderColor.getColorForState(getState(),
                        DEFAULT_BORDER_COLOR));
            }
        }

        public boolean isOval() {
            return mOval;
        }

        public void setOval(boolean oval) {
            mOval = oval;
        }

        public ScaleType getScaleType() {
            return mScaleType;
        }

        public void setScaleType(ScaleType scaleType) {
            if (scaleType == null) {
                return;
            }
            mScaleType = scaleType;
        }
    }

}

将 styleable 添加到 res 文件夹下的 attr 文件

<declare-styleable name="RoundCornerImageView">
        <attr name="sriv_left_top_corner_radius" format="dimension" />
        <attr name="sriv_right_top_corner_radius" format="dimension" />
        <attr name="sriv_left_bottom_corner_radius" format="dimension" />
        <attr name="sriv_right_bottom_corner_radius" format="dimension" />
        <attr name="sriv_border_width" format="dimension" />
        <attr name="sriv_border_color" format="color" />
        <attr name="sriv_oval" format="boolean" />
        <attr name="android:scaleType" />
    </declare-styleable>

用于 XML 文件：

 <com.skd.stackdemo.RoundCornerImageView
        android:layout_width="300dp"
        android:layout_height="300dp"
        android:src="@drawable/android"
        android:scaleType="centerCrop"
        app:sriv_left_top_corner_radius="0dp"
        app:sriv_right_top_corner_radius="20dp"
        app:sriv_left_bottom_corner_radius="0dp"
        app:sriv_right_bottom_corner_radius="0dp"
        app:sriv_oval="false" />

以上代码的输出是：

有关详细信息，请查看此 github 项目：SelectableRoundedImageView

希望对你有用

Answer 3

Material Components library从版本1.2.0-alpha03开始引入了ShapeableImageView。

只需使用类似的东西：

  <com.google.android.material.imageview.ShapeableImageView
      android:id="@+id/image_view"
      android:scaleType="centerInside"
      android:adjustViewBounds="true"
      ../>

然后在您的代码中，您可以将 ShapeAppearanceModel 应用为：

ShapeableImageView imageView = findViewById(R.id.image_view);
float radius = getResources().getDimension(R.dimen.default_corner_radius);
imageView.setShapeAppearanceModel(imageView.getShapeAppearanceModel()
    .toBuilder()
    .setTopRightCorner(CornerFamily.ROUNDED,radius)
    .build());

您也可以在xml中应用shapeAppearanceOverlay参数：

<com.google.android.material.imageview.ShapeableImageView
      app:shapeAppearanceOverlay="@style/customRroundedImageView"
      app:srcCompat="@drawable/ic_image" />

与：

  <style name="customRoundedImageView" parent="">
    <item name="cornerFamily">rounded</item>
    <item name="cornerSize">0dp</item>   
    <item name="cornerSizeTopRight">8dp</item>
  </style>

使用 jetpack compose 你可以应用 clip Modifier using a RoundedCornerShape:

Image(painterResource(id = R.drawable.xxx),
    contentDescription = "xxxx",
    contentScale = ContentScale.Crop,
    modifier = Modifier
        .size(xx.dp,xx.dp)
        .clip(RoundedCornerShape(topStart = 12.dp)),
)

Answer 4

此外，如果您想摆脱在“.java”文件中编写代码。然后你可以像下面这样定义 style 并将它添加到你的 ShapeableImageView:

<com.google.android.material.imageview.ShapeableImageView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:src="@drawable/ex_image"
    app:shapeAppearanceOverlay="@style/roundedImageView"
    />

然后：

<style name="roundedImageView" parent="">
    <item name="cornerFamilyTopRight">rounded</item>
    <item name="cornerSizeTopRight">30dp</item>
</style>

只有一个圆角的ImageView

ImageView with only one rounded corner

android

android-shape

android-shapedrawable

material-components

material-components-android