android - ImageView 中带圆角的位图

Question

我有一个 ImageView，我想用rounded corners.

我用这个：

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android" android:shape="rectangle"> 
    <solid  android:color="@null"/>    

    <stroke android:width="1dp"
            android:color="#ff000000"/>


    <corners android:radius="62px"/> 
</shape>

并将此代码设置为我的 imageview 的背景。它可以工作，但是我放在上面的 src 图像ImageView超出了边界并且不能适应新的形状。

我该如何解决这个问题？

score 87 · Accepted Answer

试试这个：

public class CustomImageView extends ImageView {

    public static float radius = 18.0f;  

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

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

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

    @Override
    protected void onDraw(Canvas canvas) {
        //float radius = 36.0f;  
        Path clipPath = new Path();
        RectF rect = new RectF(0, 0, this.getWidth(), this.getHeight());
        clipPath.addRoundRect(rect, radius, radius, Path.Direction.CW);
        canvas.clipPath(clipPath);
        super.onDraw(canvas);
    }
}

和

<your.pack.name.CustomImageView
                android:id="@+id/selectIcon"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_centerInParent="true"
                android:scaleType="centerCrop" />

CustomImageView  iconImage = (CustomImageView )findViewById(R.id.selectIcon);
iconImage.setImageBitmap(bitmap);

或者，

ImageView iv= new CustomImageView(this);
iv.setImageResource(R.drawable.pic);

score 33 · Accepted Answer

奇怪的是，这里没有人提到Android Support Library v4 中的RoundedBitmapDrawable。对我来说，这是获得无边界圆角的最简单方法。以下是使用示例：

RoundedBitmapDrawable roundedBitmapDrawable = RoundedBitmapDrawableFactory.create(getResources(), bitmap);
final float roundPx = (float) bitmap.getWidth() * 0.06f;
roundedBitmapDrawable.setCornerRadius(roundPx);

score 23 · Accepted Answer

使用画布制作一个使位图四舍五入的功能。

public static Bitmap getRoundedCornerBitmap(Bitmap bitmap, int pixels) {
    Bitmap output = Bitmap.createBitmap(bitmap.getWidth(), bitmap
            .getHeight(), 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());
    final RectF rectF = new RectF(rect);
    final float roundPx = pixels;

    paint.setAntiAlias(true);
    canvas.drawARGB(0, 0, 0, 0);
    paint.setColor(color);
    canvas.drawRoundRect(rectF, roundPx, roundPx, paint);

    paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN));
    canvas.drawBitmap(bitmap, rect, rect, paint);

    return output;
}

欲了解更多信息：>这里

score 9 · Accepted Answer

接受的答案使用路径裁剪，但它不支持抗锯齿。请参阅 Romain Guy 对其帖子的评论。“路径裁剪不支持抗锯齿，你会得到锯齿状的边缘。”

http://www.curious-creature.com/2012/12/11/android-recipe-1-image-with-rounded-corners/

有一个很好的库（vinc3m1 的 RoundedImageView）支持 ImageView 上的圆角，但它只支持每个角上的相同半径。所以我做了一个，你可以在每个角落设置不同的半径。

它不依赖路径裁剪，也不重绘。它只用canvas.drawPath()方法绘制一次。所以我终于得到了我想要的结果，如下所示。

在此处输入图像描述

请参阅：https ://github.com/pungrue26/SelectableRoundedImageView

score 6 · Accepted Answer

如果您需要制作具有不同角半径的位图，我建议您遵循以下代码：

private static Bitmap createRoundedRectBitmap(@NonNull Bitmap bitmap,
                                float topLeftCorner, float topRightCorner,
                                float bottomRightCorner, float bottomLeftCorner) {
    Bitmap output = Bitmap.createBitmap(bitmap.getWidth(), bitmap.getHeight(), 
                                        Bitmap.Config.ARGB_8888);
    Canvas canvas = new Canvas(output);

    final int color = Color.WHITE;
    final Paint paint = new Paint();
    final Rect rect = new Rect(0, 0, bitmap.getWidth(), bitmap.getHeight());
    final RectF rectF = new RectF(rect);
    Path path = new Path();
    float[] radii = new float[]{
            topLeftCorner, bottomLeftCorner,
            topRightCorner, topRightCorner,
            bottomRightCorner, bottomRightCorner,
            bottomLeftCorner, bottomLeftCorner
    };

    paint.setAntiAlias(true);
    canvas.drawARGB(0, 0, 0, 0);
    paint.setColor(color);
    path.addRoundRect(rectF, radii, Path.Direction.CW);
    canvas.drawPath(path, paint);
    paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_IN));
    canvas.drawBitmap(bitmap, rect, rect, paint);
    return output;
}

score 5 · Accepted Answer

如果您还需要边框，那么： 1. 您可以使用带有透明主体和外部白色的圆角框图像。例如：

圆角盒

并将其与目标图像一起使用，如下所示：

<FrameLayout
android:layout_width="100px"
android:layout_height="100px" >
<ImageView
        android:id="@+id/targetImage"
        android:layout_width="100px"
        android:layout_height="100px"
        android:src="@drawable/app_icon"
        android:layout_gravity="center" />
<ImageView
        android:id="@+id/boxImage"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:scaleType="fitXY"
        android:src="@drawable/box" />

添加CardView作为父布局ImageView也是一个很好的解决方案。

score 4 · Accepted Answer

对我来说，下面的方法很神奇。:) 这个方法接受一个位图对象并用圆角返回它。roundPx是您想要的四舍五入像素数：

public static Bitmap getRoundedCornerBitmap(Bitmap bitmap) {
    Bitmap output = Bitmap.createBitmap(bitmap.getWidth(),
    bitmap.getHeight(), 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());
    final RectF rectF = new RectF(rect);
    final float roundPx = 12;

    paint.setAntiAlias(true);
    canvas.drawARGB(0, 0, 0, 0);
    paint.setColor(color);
    canvas.drawRoundRect(rectF, roundPx, roundPx, paint);

    paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN));
    canvas.drawBitmap(bitmap, rect, rect, paint);

    return output;
}

...或者您可以使用这个库而不是ImageView而无需任何进一步的编码。

score 3 · Accepted Answer

它可以通过背景可绘制来完成，就像在包括这篇文章在内的许多帖子中解释的那样，但它还需要设置剪辑。这里有一个完整的例子：

编码：

AppCompatImageView iconView = findViewById(R.id.thumbnail);
iconView.setClipToOutline(true);

布局：

<android.support.v7.widget.AppCompatImageView
    android:id="@+id/thumbnail"
    android:layout_width="80dp"
    android:layout_height="80dp"
    android:contentDescription="@string/thumbnail"
    android:scaleType="centerInside"
    android:background="@drawable/round_view" <!--here set the drawable as background -->
    tools:src="@mipmap/ic_user" />

可绘制对象：

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="rectangle">
    <corners android:radius="10dp" />
</shape>

score 0 · Accepted Answer

public class RoundedImageView extends ImageView {

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

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

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

    @Override
    protected void onDraw(Canvas canvas) {

        super.onDraw(canvas);

        Bitmap rounder = Bitmap.createBitmap(getWidth(),getHeight(),Bitmap.Config.ARGB_8888);
        Canvas canvasRound = new Canvas(rounder);    

        Paint xferPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
        xferPaint.setColor(Color.BLACK);

        final int rx = this.getWidth(); //our x radius
        final int ry = this.getHeight(); //our y radius

        canvasRound.drawRoundRect(new RectF(0,0,rx,ry), rx, ry, xferPaint);     

        xferPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.DST_IN));

        canvas.drawBitmap(rounder, 0, 0, xferPaint);

    }

}

score 0 · Accepted Answer

/**
 * Creates new circular bitmap based on original one.
 * @param newCornerRadius is optional
 */
fun Bitmap.toCircular(context: Context, newCornerRadius: Float? = null): RoundedBitmapDrawable {
    return RoundedBitmapDrawableFactory.create(context.resources, this).apply {
        isCircular = true
        newCornerRadius?.let {
            cornerRadius = it
        }
    }
}

score -4 · Accepted Answer

public void drawRoundImage(boolean isEditPicEnable){
   if(originalImageBitmap != null){
        setBackgroundResource(R.drawable.ic_account_user_outer_circle_blue);

        if (isEditPicEnable) {
            setBackgroundResource(R.drawable.ic_account_user_outer_circle_white);
            Bitmap mask = BitmapFactory.decodeResource(getResources(), R.drawable.ic_account_white_mask);
            Bitmap mask1 = BitmapFactory.decodeResource(getResources(), R.drawable.ic_account_pencil_bg);
            originalImageBitmap = Bitmap.createScaledBitmap(originalImageBitmap, mask.getWidth(), mask.getHeight(), true);
            Bitmap result = Bitmap.createBitmap(mask.getWidth(), mask.getHeight(), Bitmap.Config.ARGB_8888);
            Canvas mCanvas = new Canvas(result);
            Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG);
            paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.DST_IN));
            mCanvas.drawBitmap(originalImageBitmap, 0, 0, null);
            mCanvas.drawBitmap(mask, 0, 0, paint);
            mCanvas.drawBitmap(mask1, 0, 0, null);
            Bitmap mask2 = BitmapFactory.decodeResource(getResources(), R.drawable.ic_account_pencil);
            mCanvas.drawBitmap(mask2, 0, 0, null);
            setImageBitmap(result);
            setScaleType(ScaleType.FIT_XY);
        } else {
            Bitmap mask = BitmapFactory.decodeResource(getResources(),R.drawable.ic_account_white_mask);
            originalImageBitmap = Bitmap.createScaledBitmap(originalImageBitmap, mask.getWidth(),mask.getHeight(), true);
            Bitmap result = Bitmap.createBitmap(mask.getWidth(), mask.getHeight(),Bitmap.Config.ARGB_8888);
            Canvas mCanvas = new Canvas(result);
            Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG);
            paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.DST_IN));
            mCanvas.drawBitmap(originalImageBitmap, 0, 0, null);
            mCanvas.drawBitmap(mask, 0, 0, paint);
            paint.setXfermode(null);
            setImageBitmap(result);
            setScaleType(ScaleType.FIT_XY);
        }

    }else{
        setBackgroundResource(R.drawable.ic_account_user_outer_circle_blue);
        setImageResource(R.drawable.my_ac_default_profile_pic);
    }

}

score -4 · Accepted Answer

在android中为imageview制作圆角的方法不是火箭科学的家伙！只需使用具有与背景颜色相同的所需曲线的 png 并将叠加设置为 FITXY。！

android - ImageView 中带圆角的位图

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