blocks|key|499906|text|我不确定这是一个编程问题，但是...|type|unstyled|depth|inlineStyleRanges|entityRanges|data|499907|最简单的解决方案是在源位图中使外部区域透明。否则，您必须计算哪些像素在圆之外，并相应地设置alpha+(alpha+=0表示完全透明)。|499908|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|F|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|G|8|@]|9|@]|A|$]]|$1|D|3|-4|5|6|7|H|8|@]|9|@]|A|$]]]|E|$]]

Not sure this is a programming question but...

The easiest solution would be to make the outside area transparent in the source bitmap. Otherwise, you'll have to calculate which pixels are outside of the circle, and set the alpha accordingly (alpha = 0 for full transparency).

blocks|key|499996|text|经过长时间的头脑风暴，我找到了解决方案。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|499997|public+Bitmap+getCroppedBitmap(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());

++++paint.setAntiAlias(true);
++++canvas.drawARGB(0,+0,+0,+0);
++++paint.setColor(color);
++++//+canvas.drawRoundRect(rectF,+roundPx,+roundPx,+paint);
++++canvas.drawCircle(bitmap.getWidth()+/+2,+bitmap.getHeight()+/+2,
++++++++++++bitmap.getWidth()+/+2,+paint);
++++paint.setXfermode(new+PorterDuffXfermode(Mode.SRC_IN));
++++canvas.drawBitmap(bitmap,+rect,+rect,+paint);
++++//Bitmap+_bmp+=+Bitmap.createScaledBitmap(output,+60,+60,+false);
++++//return+_bmp;
++++return+output;
}|code-block|syntax|javascript|499998|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

After long brainstorming I have found the solution

<pre><code>public Bitmap getCroppedBitmap(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());

 paint.setAntiAlias(true);
 canvas.drawARGB(0, 0, 0, 0);
 paint.setColor(color);
 // canvas.drawRoundRect(rectF, roundPx, roundPx, paint);
 canvas.drawCircle(bitmap.getWidth() / 2, bitmap.getHeight() / 2,
 bitmap.getWidth() / 2, paint);
 paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN));
 canvas.drawBitmap(bitmap, rect, rect, paint);
 //Bitmap _bmp = Bitmap.createScaledBitmap(output, 60, 60, false);
 //return _bmp;
 return output;
}
</code></pre>

blocks|key|500051|text|@Gene对上面的答案进行了评论，建议使用clipPath作为将图像裁剪为圆圈的选项。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|500052|下面是它的一个干净的实现：|500053|++++public+static+Bitmap+GetBitmapClippedCircle(Bitmap+bitmap)+{

++++++++final+int+width+=+bitmap.getWidth();
++++++++final+int+height+=+bitmap.getHeight();
++++++++final+Bitmap+outputBitmap+=+Bitmap.createBitmap(width,+height,+Config.ARGB_8888);

++++++++final+Path+path+=+new+Path();
++++++++path.addCircle(
++++++++++++++++++(float)(width+/+2)
++++++++++++++++,+(float)(height+/+2)
++++++++++++++++,+(float)+Math.min(width,+(height+/+2))
++++++++++++++++,+Path.Direction.CCW);

++++++++final+Canvas+canvas+=+new+Canvas(outputBitmap);
++++++++canvas.clipPath(path);
++++++++canvas.drawBitmap(bitmap,+0,+0,+null);
++++++++return+outputBitmap;
++++}|code-block|syntax|javascript|500054|这可以添加到一个实用程序类中。|500055|entityMap^0|L|8|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@$9|R|A|S|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|T|8|@]|D|@]|E|$]]|$1|H|3|I|5|J|7|U|8|@]|D|@]|E|$K|L]]|$1|M|3|N|5|6|7|V|8|@]|D|@]|E|$]]|$1|O|3|-4|5|6|7|W|8|@]|D|@]|E|$]]]|P|$]]

@Gene made a comment on the answer above that suggested using <code>clipPath</code> as an option for cropping an image as a circle.

The following is a clean implementation of this:

<pre><code> public static Bitmap GetBitmapClippedCircle(Bitmap bitmap) {

 final int width = bitmap.getWidth();
 final int height = bitmap.getHeight();
 final Bitmap outputBitmap = Bitmap.createBitmap(width, height, Config.ARGB_8888);

 final Path path = new Path();
 path.addCircle(
 (float)(width / 2)
 , (float)(height / 2)
 , (float) Math.min(width, (height / 2))
 , Path.Direction.CCW);

 final Canvas canvas = new Canvas(outputBitmap);
 canvas.clipPath(path);
 canvas.drawBitmap(bitmap, 0, 0, null);
 return outputBitmap;
 }
</code></pre>

This could be added to a utility class.

blocks|key|283392|text|从矩形生成圆的步骤|type|unstyled|depth|inlineStyleRanges|entityRanges|data|283393|public+static+Bitmap+getCircularBitmap(Bitmap+bitmap)+{
++++Bitmap+output;

++++if+(bitmap.getWidth()+>+bitmap.getHeight())+{
++++++++output+=+Bitmap.createBitmap(bitmap.getHeight(),+bitmap.getHeight(),+Config.ARGB_8888);
++++}+else+{
++++++++output+=+Bitmap.createBitmap(bitmap.getWidth(),+bitmap.getWidth(),+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(Mode.SRC_IN));
++++canvas.drawBitmap(bitmap,+rect,+rect,+paint);
++++return+output;
}|code-block|syntax|javascript|283394|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

<h1>to generate Circle from rectangles</h1>

<pre class="lang-java prettyprint-override"><code>public static Bitmap getCircularBitmap(Bitmap bitmap) {
 Bitmap output;

 if (bitmap.getWidth() &gt; bitmap.getHeight()) {
 output = Bitmap.createBitmap(bitmap.getHeight(), bitmap.getHeight(), Config.ARGB_8888);
 } else {
 output = Bitmap.createBitmap(bitmap.getWidth(), bitmap.getWidth(), 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() &gt; 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(Mode.SRC_IN));
 canvas.drawBitmap(bitmap, rect, rect, paint);
 return output;
}
</code></pre>

blocks|key|283437|text|你可以使用这段代码，它会工作的|type|unstyled|depth|inlineStyleRanges|entityRanges|data|283438|public+Bitmap+getRoundedShape(Bitmap+scaleBitmapImage)+{
++++int+targetWidth+=+110;
++++int+targetHeight+=+110;
++++Bitmap+targetBitmap+=+Bitmap.createBitmap(targetWidth,+
++++++++++++targetHeight,Bitmap.Config.ARGB_8888);

++++Canvas+canvas+=+new+Canvas(targetBitmap);
++++Path+path+=+new+Path();
++++path.addCircle(((float)+targetWidth+-+1)+/+2,
++++++++++++((float)+targetHeight+-+1)+/+2,
++++++++++++(Math.min(((float)+targetWidth),+
++++++++++++++++++++((float)+targetHeight))+/+2),
++++++++++++++++++++Path.Direction.CCW);

++++canvas.clipPath(path);
++++Bitmap+sourceBitmap+=+scaleBitmapImage;
++++canvas.drawBitmap(sourceBitmap,+
++++++++++++new+Rect(0,+0,+sourceBitmap.getWidth(),
++++++++++++++++++++sourceBitmap.getHeight()),+
++++++++++++++++++++new+Rect(0,+0,+targetWidth,+targetHeight),+new+Paint(Paint.FILTER_BITMAP_FLAG));
++++return+targetBitmap;
}|code-block|syntax|javascript|283439|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

you can use this code, it will work

<pre><code>public Bitmap getRoundedShape(Bitmap scaleBitmapImage) {
 int targetWidth = 110;
 int targetHeight = 110;
 Bitmap targetBitmap = Bitmap.createBitmap(targetWidth, 
 targetHeight,Bitmap.Config.ARGB_8888);

 Canvas canvas = new Canvas(targetBitmap);
 Path path = new Path();
 path.addCircle(((float) targetWidth - 1) / 2,
 ((float) targetHeight - 1) / 2,
 (Math.min(((float) targetWidth), 
 ((float) targetHeight)) / 2),
 Path.Direction.CCW);

 canvas.clipPath(path);
 Bitmap sourceBitmap = scaleBitmapImage;
 canvas.drawBitmap(sourceBitmap, 
 new Rect(0, 0, sourceBitmap.getWidth(),
 sourceBitmap.getHeight()), 
 new Rect(0, 0, targetWidth, targetHeight), new Paint(Paint.FILTER_BITMAP_FLAG));
 return targetBitmap;
}
</code></pre>

blocks|key|500162|text|如果你不再需要它，我建议你添加bitmap.recycle()，它可以防止OutOfMemory错误。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|500163|entityMap^0|F|G|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|K|8|@]|D|@]|E|$]]]|G|$]]

I recommend adding <code>bitmap.recycle()</code> if you don't need it anymore, it will prevent OutOfMemory error.

blocks|key|500208|text|我认为这个解决方案适用于任何类型的矩形，如果您想要图像小或大，请更改像素大小：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|500209|public+static+Bitmap+getCircleBitmap(Bitmap+bm)+{

++++++++int+sice+=+Math.min((bm.getWidth()),+(bm.getHeight()));

++++++++Bitmap+bitmap+=+ThumbnailUtils.extractThumbnail(bm,+sice,+sice);

++++++++Bitmap+output+=+Bitmap.createBitmap(bitmap.getWidth(),+bitmap.getHeight(),+Bitmap.Config.ARGB_8888);

++++++++Canvas+canvas+=+new+Canvas(output);

++++++++final+int+color+=+0xffff0000;
++++++++final+Paint+paint+=+new+Paint();
++++++++final+Rect+rect+=+new+Rect(0,+0,+bitmap.getWidth(),+bitmap.getHeight());
++++++++final+RectF+rectF+=+new+RectF(rect);

++++++++paint.setAntiAlias(true);
++++++++paint.setDither(true);
++++++++paint.setFilterBitmap(true);
++++++++canvas.drawARGB(0,+0,+0,+0);
++++++++paint.setColor(color);
++++++++canvas.drawOval(rectF,+paint);

++++++++paint.setColor(Color.BLUE);
++++++++paint.setStyle(Paint.Style.STROKE);
++++++++paint.setStrokeWidth((float)+4);
++++++++paint.setXfermode(new+PorterDuffXfermode(Mode.SRC_IN));
++++++++canvas.drawBitmap(bitmap,+rect,+rect,+paint);

++++++++return+output;
++++}|code-block|syntax|javascript|500210|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

I think this solution works better with any type of rectangle, change the pixel size if you want image small or large :

<pre><code>public static Bitmap getCircleBitmap(Bitmap bm) {

 int sice = Math.min((bm.getWidth()), (bm.getHeight()));

 Bitmap bitmap = ThumbnailUtils.extractThumbnail(bm, sice, sice);

 Bitmap output = Bitmap.createBitmap(bitmap.getWidth(), bitmap.getHeight(), Bitmap.Config.ARGB_8888);

 Canvas canvas = new Canvas(output);

 final int color = 0xffff0000;
 final Paint paint = new Paint();
 final Rect rect = new Rect(0, 0, bitmap.getWidth(), bitmap.getHeight());
 final RectF rectF = new RectF(rect);

 paint.setAntiAlias(true);
 paint.setDither(true);
 paint.setFilterBitmap(true);
 canvas.drawARGB(0, 0, 0, 0);
 paint.setColor(color);
 canvas.drawOval(rectF, paint);

 paint.setColor(Color.BLUE);
 paint.setStyle(Paint.Style.STROKE);
 paint.setStrokeWidth((float) 4);
 paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN));
 canvas.drawBitmap(bitmap, rect, rect, paint);

 return output;
 }
</code></pre>

blocks|key|500234|text|您可以使用RoundedBitmapDrawable使您的图像视图成为圆形|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|500235|下面是实现roundedImageview的代码：|500236|ImageView+profilePic=(ImageView)findViewById(R.id.user_image);

//get+bitmap+of+the+image
Bitmap+imageBitmap=BitmapFactory.decodeResource(getResources(),++R.drawable.large_icon);
RoundedBitmapDrawable+roundedBitmapDrawable=RoundedBitmapDrawableFactory.create(getResources(),+imageBitmap);

//setting+radius
roundedBitmapDrawable.setCornerRadius(50.0f);
roundedBitmapDrawable.setAntiAlias(true);
profilePic.setImageDrawable(roundedBitmapDrawable);|code-block|syntax|javascript|500237|entityMap|0|LINK|mutability|MUTABLE|url|http://developer.android.com/reference/android/support/v4/graphics/drawable/RoundedBitmapDrawable.html^0|5|L|0|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@$A|T|B|U|1|V]]|C|$]]|$1|D|3|E|5|6|7|W|8|@]|9|@]|C|$]]|$1|F|3|G|5|H|7|X|8|@]|9|@]|C|$I|J]]|$1|K|3|-4|5|6|7|Y|8|@]|9|@]|C|$]]]|L|$M|$5|N|O|P|C|$Q|R]]]]

You Can make your imageview circular using <a href="http://developer.android.com/reference/android/support/v4/graphics/drawable/RoundedBitmapDrawable.html" rel="noreferrer">RoundedBitmapDrawable</a>

here is the code for achieving roundedImageview:

<pre><code>ImageView profilePic=(ImageView)findViewById(R.id.user_image);

//get bitmap of the image
Bitmap imageBitmap=BitmapFactory.decodeResource(getResources(), R.drawable.large_icon);
RoundedBitmapDrawable roundedBitmapDrawable=RoundedBitmapDrawableFactory.create(getResources(), imageBitmap);

//setting radius
roundedBitmapDrawable.setCornerRadius(50.0f);
roundedBitmapDrawable.setAntiAlias(true);
profilePic.setImageDrawable(roundedBitmapDrawable);
</code></pre>

blocks|key|283584|text|对于想要矩形中心的人(我)，在剪切之前添加以下内容：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|283585|++++public+static+Bitmap+cropBitmapToBlock(Bitmap+bitmap)+{
++++if+(bitmap.getWidth()+>=+bitmap.getHeight()){
++++++++return+Bitmap.createBitmap(
++++++++++++++++bitmap,
++++++++++++++++bitmap.getWidth()/2+-+bitmap.getHeight()/2,
++++++++++++++++0,
++++++++++++++++bitmap.getHeight(),
++++++++++++++++bitmap.getHeight()
++++++++);
++++}else{
++++++++return+Bitmap.createBitmap(
++++++++++++++++bitmap,
++++++++++++++++0,
++++++++++++++++bitmap.getHeight()/2+-+bitmap.getWidth()/2,
++++++++++++++++bitmap.getWidth(),
++++++++++++++++bitmap.getWidth()
++++++++);
++++}
}+|code-block|syntax|javascript|283586|Android+Crop+Center+of+Bitmap|offset|length|283587|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/questions/6908604/android-crop-center-of-bitmap^0|0|0|0|T|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|T|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|U|8|@]|9|@$I|V|J|W|1|X]]|A|$]]|$1|K|3|-4|5|6|7|Y|8|@]|9|@]|A|$]]]|L|$M|$5|N|O|P|A|$Q|R]]]]

For peaple who want the center of the rectangle (me), add this before cutting:

<pre><code> public static Bitmap cropBitmapToBlock(Bitmap bitmap) {
 if (bitmap.getWidth() &gt;= bitmap.getHeight()){
 return Bitmap.createBitmap(
 bitmap,
 bitmap.getWidth()/2 - bitmap.getHeight()/2,
 0,
 bitmap.getHeight(),
 bitmap.getHeight()
 );
 }else{
 return Bitmap.createBitmap(
 bitmap,
 0,
 bitmap.getHeight()/2 - bitmap.getWidth()/2,
 bitmap.getWidth(),
 bitmap.getWidth()
 );
 }
} 
</code></pre>

<a href="https://stackoverflow.com/questions/6908604/android-crop-center-of-bitmap">Android Crop Center of Bitmap</a>

blocks|key|500287|text|你可以使用这段代码，它会工作的|type|unstyled|depth|inlineStyleRanges|entityRanges|data|500288|+private+Bitmap+getCircleBitmap(Bitmap+bitmap)+{
++++++++final+Bitmap+output+=+Bitmap.createBitmap(bitmap.getWidth(),
++++++++++++++++bitmap.getHeight(),+Bitmap.Config.ARGB_8888);
++++++++final+Canvas+canvas+=+new+Canvas(output);

++++++++final+int+color+=+Color.RED;
++++++++final+Paint+paint+=+new+Paint();
++++++++final+Rect+rect+=+new+Rect(0,+0,+bitmap.getWidth(),+bitmap.getHeight());
++++++++final+RectF+rectF+=+new+RectF(rect);

++++++++paint.setAntiAlias(true);
++++++++canvas.drawARGB(0,+0,+0,+0);
++++++++paint.setColor(color);
++++++++canvas.drawOval(rectF,+paint);

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

++++++++bitmap.recycle();

++++++++return+output;
++++}|code-block|syntax|javascript|500289|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

you can use this code, it will work

<pre><code> private Bitmap getCircleBitmap(Bitmap bitmap) {
 final Bitmap output = Bitmap.createBitmap(bitmap.getWidth(),
 bitmap.getHeight(), Bitmap.Config.ARGB_8888);
 final Canvas canvas = new Canvas(output);

 final int color = Color.RED;
 final Paint paint = new Paint();
 final Rect rect = new Rect(0, 0, bitmap.getWidth(), bitmap.getHeight());
 final RectF rectF = new RectF(rect);

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

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

 bitmap.recycle();

 return output;
 }
</code></pre>

blocks|key|283655|text|基于Jachumbelechao+Mantekilla+a的答案，对于寻找Kotlin解决方案的人来说，这段代码就像一个护身符：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|283656|fun+cropCircleFromBitmap(originalBitmap:+Bitmap):+Bitmap+{
++++val+size+=+Math.min(originalBitmap.width,+originalBitmap.height)
++++val+bitmap+=+ThumbnailUtils.extractThumbnail(originalBitmap,+size,+size)
++++var+output+=+Bitmap.createBitmap(bitmap.width,+bitmap.height,+Bitmap.Config.ARGB_8888)
++++val+canvas+=+Canvas(output)
++++val+paint+=+Paint()
++++val+rect+=+Rect(0,+0,+bitmap.width,+bitmap.height)
++++val+rectF+=+RectF(rect)
++++paint.isAntiAlias+=+true
++++paint.isDither+=+true
++++paint.isFilterBitmap+=+true
++++canvas.drawARGB(0,+0,+0,+0)
++++paint.color+=+0xffff0000.toInt()
++++canvas.drawOval(rectF,+paint)
++++paint.color+=+Color.BLUE
++++paint.style+=+Paint.Style.STROKE
++++paint.strokeWidth+=+4f
++++paint.xfermode+=+PorterDuffXfermode(PorterDuff.Mode.SRC_IN);
++++canvas.drawBitmap(bitmap,+rect,+rect,+paint)
++++return+output
}|code-block|syntax|javascript|283657|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Based on [Jachumbelechao Unto Mantekilla] answer, this code works like a charm for people looking for a Kotlin solution:

<pre><code>fun cropCircleFromBitmap(originalBitmap: Bitmap): Bitmap {
 val size = Math.min(originalBitmap.width, originalBitmap.height)
 val bitmap = ThumbnailUtils.extractThumbnail(originalBitmap, size, size)
 var output = Bitmap.createBitmap(bitmap.width, bitmap.height, Bitmap.Config.ARGB_8888)
 val canvas = Canvas(output)
 val paint = Paint()
 val rect = Rect(0, 0, bitmap.width, bitmap.height)
 val rectF = RectF(rect)
 paint.isAntiAlias = true
 paint.isDither = true
 paint.isFilterBitmap = true
 canvas.drawARGB(0, 0, 0, 0)
 paint.color = 0xffff0000.toInt()
 canvas.drawOval(rectF, paint)
 paint.color = Color.BLUE
 paint.style = Paint.Style.STROKE
 paint.strokeWidth = 4f
 paint.xfermode = PorterDuffXfermode(PorterDuff.Mode.SRC_IN);
 canvas.drawBitmap(bitmap, rect, rect, paint)
 return output
}
</code></pre>

blocks|key|500363|text|现在，正确回答：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|500364|private+Bitmap+getCroppedBitmap(Bitmap+bitmap,+Integer+cx,+Integer+cy,+Integer+radius)+{
++++int+diam+=+radius+<<+1;
++++Bitmap+targetBitmap+=+Bitmap.createBitmap(diam,+diam,+Bitmap.Config.ARGB_8888);
++++Canvas+canvas+=+new+Canvas(targetBitmap);
++++final+int+color+=+0xff424242;
++++final+Paint+paint+=+new+Paint(Paint.ANTI_ALIAS_FLAG);
++++canvas.drawARGB(0,+0,+0,+0);
++++paint.setColor(color);
++++canvas.drawCircle(radius,+radius,+radius,+paint);
++++paint.setXfermode(new+PorterDuffXfermode(PorterDuff.Mode.SRC_IN));
++++canvas.drawBitmap(bitmap,+-cx%2Bradius,+-cy%2Bradius,+paint);
++++return+targetBitmap;
}|code-block|syntax|javascript|500365|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Now, Right answer:

<pre><code>private Bitmap getCroppedBitmap(Bitmap bitmap, Integer cx, Integer cy, Integer radius) {
 int diam = radius &lt;&lt; 1;
 Bitmap targetBitmap = Bitmap.createBitmap(diam, diam, Bitmap.Config.ARGB_8888);
 Canvas canvas = new Canvas(targetBitmap);
 final int color = 0xff424242;
 final Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG);
 canvas.drawARGB(0, 0, 0, 0);
 paint.setColor(color);
 canvas.drawCircle(radius, radius, radius, paint);
 paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_IN));
 canvas.drawBitmap(bitmap, -cx+radius, -cy+radius, paint);
 return targetBitmap;
}
</code></pre>

blocks|key|283729|text|下面是使用扩展方法的Kotlin变体|type|unstyled|depth|inlineStyleRanges|entityRanges|data|283730|/**
+*+Creates+new+circular+bitmap+based+on+original+one.
+*/
fun+Bitmap.getCircularBitmap(config:+Bitmap.Config+=+Bitmap.Config.ARGB_8888):+Bitmap+{
++++//+circle+configuration
++++val+circlePaint+=+Paint().apply+{+isAntiAlias+=+true+}
++++val+circleRadius+=+Math.max(width,+height)+/+2f

++++//+output+bitmap
++++val+outputBitmapPaint+=+Paint(circlePaint).apply+{+xfermode+=+PorterDuffXfermode(PorterDuff.Mode.SRC_IN)+}
++++val+outputBounds+=+Rect(0,+0,+width,+height)
++++val+output+=+Bitmap.createBitmap(width,+height,+config)

++++return+Canvas(output).run+{
++++++++drawCircle(circleRadius,+circleRadius,+circleRadius,+circlePaint)
++++++++drawBitmap(this@getCircularBitmap,+outputBounds,+outputBounds,+outputBitmapPaint)
++++++++output
++++}
}|code-block|syntax|javascript|283731|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Here is Kotlin variant using extension method

<pre><code>/**
 * Creates new circular bitmap based on original one.
 */
fun Bitmap.getCircularBitmap(config: Bitmap.Config = Bitmap.Config.ARGB_8888): Bitmap {
 // circle configuration
 val circlePaint = Paint().apply { isAntiAlias = true }
 val circleRadius = Math.max(width, height) / 2f

 // output bitmap
 val outputBitmapPaint = Paint(circlePaint).apply { xfermode = PorterDuffXfermode(PorterDuff.Mode.SRC_IN) }
 val outputBounds = Rect(0, 0, width, height)
 val output = Bitmap.createBitmap(width, height, config)

 return Canvas(output).run {
 drawCircle(circleRadius, circleRadius, circleRadius, circlePaint)
 drawBitmap(this@getCircularBitmap, outputBounds, outputBounds, outputBitmapPaint)
 output
 }
}
</code></pre>

blocks|key|500626|text|Kotin函数|type|unstyled|depth|inlineStyleRanges|entityRanges|data|500627|+fun+getRoundedCornerBitmap(bitmap:+Bitmap,+pixels:+Int):+Bitmap+{
++++++++++++val+output+=+Bitmap.createBitmap(bitmap.width,+bitmap.height,+Bitmap.Config.ARGB_8888)
++++++++++++val+canvas+=+Canvas(output)

++++++++++++val+color+=+-0xbdbdbe
++++++++++++val+paint+=+Paint()
++++++++++++val+rect+=+Rect(0,+0,+bitmap.width,+bitmap.height)
++++++++++++val+rectF+=+RectF(rect)
++++++++++++val+roundPx+=+pixels.toFloat()

++++++++++++paint.isAntiAlias+=+true
++++++++++++canvas.drawARGB(0,+0,+0,+0)
++++++++++++paint.color+=+color
++++++++++++canvas.drawRoundRect(rectF,+roundPx,+roundPx,+paint)

++++++++++++paint.xfermode+=+PorterDuffXfermode(PorterDuff.Mode.SRC_IN)
++++++++++++canvas.drawBitmap(bitmap,+rect,+rect,+paint)

++++++++++++return+output
++++++++}|code-block|syntax|javascript|500628|通过下面的代码调用它|500629|+holder.itemFriendImage.setImageBitmap(ImageConverter.getRoundedCornerBitmap(bitmap,600))|500630|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

Kotin Fucntion

<pre><code> fun getRoundedCornerBitmap(bitmap: Bitmap, pixels: Int): Bitmap {
 val output = Bitmap.createBitmap(bitmap.width, bitmap.height, Bitmap.Config.ARGB_8888)
 val canvas = Canvas(output)

 val color = -0xbdbdbe
 val paint = Paint()
 val rect = Rect(0, 0, bitmap.width, bitmap.height)
 val rectF = RectF(rect)
 val roundPx = pixels.toFloat()

 paint.isAntiAlias = true
 canvas.drawARGB(0, 0, 0, 0)
 paint.color = color
 canvas.drawRoundRect(rectF, roundPx, roundPx, paint)

 paint.xfermode = PorterDuffXfermode(PorterDuff.Mode.SRC_IN)
 canvas.drawBitmap(bitmap, rect, rect, paint)

 return output
 }
</code></pre>

call it by this code

<pre><code> holder.itemFriendImage.setImageBitmap(ImageConverter.getRoundedCornerBitmap(bitmap,600))
</code></pre>

blocks|key|500636|text|**Jst+Add+this+to+your+image+Id+and+get+the+circuler+image.**

+imgUserProfile.setImageBitmap(getCircularCenterCropBitmap(bitmap,+(int)+(150+*+denisty)));

Method:-

public+void+Bitmap+getCircularCenterCropBitmap(Bitmap+originalBmp,+int+diameter)+{
++++++++Bitmap+resizedBmp+=+BitmapUtils.getScaledCroppedBitmap(originalBmp,+diameter,+diameter);
++++++++return+BitmapUtils.getRoundedCircularBitmap(resizedBmp,+diameter+/+2);
++++}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|500637|unstyled|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|G|8|@]|9|@]|A|$B|C]]|$1|D|3|-4|5|E|7|H|8|@]|9|@]|A|$]]]|F|$]]

<pre><code>**Jst Add this to your image Id and get the circuler image.**

 imgUserProfile.setImageBitmap(getCircularCenterCropBitmap(bitmap, (int) (150 * denisty)));

Method:-

public void Bitmap getCircularCenterCropBitmap(Bitmap originalBmp, int diameter) {
 Bitmap resizedBmp = BitmapUtils.getScaledCroppedBitmap(originalBmp, diameter, diameter);
 return BitmapUtils.getRoundedCircularBitmap(resizedBmp, diameter / 2);
 }
</code></pre>

blocks|key|283981|text|我相信最简单的解决方案是创建一个位图的半径，将它传递给你的paint对象，然后简单地调用canvas.drawCircle(cx，cy，BitmapShader，paint)；|type|unstyled|depth|inlineStyleRanges|entityRanges|data|283982|例如|283983|Paint+p+=+new+Paint();
p.setShader(new+BitmapShader(myBitmap,+Shader.TileMode.CLAMP,+Shader.TileMode.CLAMP));
canvas.drawCircle(getWidth()+/+2,+getHeight()+/+2,+getHeight()+/+2,+p);|code-block|syntax|javascript|283984|这就是https://github.com/hdodenhof/CircleImageView是如何做到这一点的，你可以在这里阅读源代码：https://github.com/hdodenhof/CircleImageView/blob/master/circleimageview/src/main/java/de/hdodenhof/circleimageview/CircleImageView.java|offset|length|283985|entityMap|0|LINK|mutability|MUTABLE|url|https://github.com/hdodenhof/CircleImageView|1|https://github.com/hdodenhof/CircleImageView/blob/master/circleimageview/src/main/java/de/hdodenhof/circleimageview/CircleImageView.java^0|0|0|0|3|18|0|1X|3S|1|0^^$0|@$1|2|3|4|5|6|7|W|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|X|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|Y|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|Z|8|@]|9|@$K|10|L|11|1|12]|$K|13|L|14|1|15]]|A|$]]|$1|M|3|-4|5|6|7|16|8|@]|9|@]|A|$]]]|N|$O|$5|P|Q|R|A|$S|T]]|U|$5|P|Q|R|A|$S|V]]]]

I believe the easiest solution is to create a BitmapShader of your Bitmap, pass it to your paint object and then simply call something like canvas.drawCircle(cx, cy, radius, paint);

for example

<pre><code>Paint p = new Paint();
p.setShader(new BitmapShader(myBitmap, Shader.TileMode.CLAMP, Shader.TileMode.CLAMP));
canvas.drawCircle(getWidth() / 2, getHeight() / 2, getHeight() / 2, p);
</code></pre>

This is how <a href="https://github.com/hdodenhof/CircleImageView" rel="nofollow noreferrer">https://github.com/hdodenhof/CircleImageView</a> also has done it,
you can read the source code here: 
<a href="https://github.com/hdodenhof/CircleImageView/blob/master/circleimageview/src/main/java/de/hdodenhof/circleimageview/CircleImageView.java" rel="nofollow noreferrer">https://github.com/hdodenhof/CircleImageView/blob/master/circleimageview/src/main/java/de/hdodenhof/circleimageview/CircleImageView.java</a>

blocks|key|284045|text|kotlin，把它放到Ext.kt里|type|unstyled|depth|inlineStyleRanges|entityRanges|data|284046|+private+fun+Bitmap.getCircledBitmap():+Bitmap+{
++++val+output+=+Bitmap.createBitmap(this.width,+this.height,+Bitmap.Config.ARGB_8888)
++++val+canvas+=+Canvas(output)
++++val+paint+=+Paint()
++++val+rect+=+Rect(0,+0,+this.width,+this.height)
++++paint.isAntiAlias+=+true
++++canvas.drawARGB(0,+0,+0,+0)
++++canvas.drawCircle(this.width+/+2f,+this.height+/+2f,+this.width+/+2f,+paint)
++++paint.xfermode+=+PorterDuffXfermode(PorterDuff.Mode.SRC_IN)
++++canvas.drawBitmap(this,+rect,+rect,+paint)
++++return+output
}|code-block|syntax|javascript|284047|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

kotlin, put it in Ext.kt
<pre><code> private fun Bitmap.getCircledBitmap(): Bitmap {
 val output = Bitmap.createBitmap(this.width, this.height, Bitmap.Config.ARGB_8888)
 val canvas = Canvas(output)
 val paint = Paint()
 val rect = Rect(0, 0, this.width, this.height)
 paint.isAntiAlias = true
 canvas.drawARGB(0, 0, 0, 0)
 canvas.drawCircle(this.width / 2f, this.height / 2f, this.width / 2f, paint)
 paint.xfermode = PorterDuffXfermode(PorterDuff.Mode.SRC_IN)
 canvas.drawBitmap(this, rect, rect, paint)
 return output
}
</code></pre>

I have a bitmap and I want to crop a circular region from this bitmap. All pixels outside the circle should be transparent. How can I do this?

<img src="https://i.stack.imgur.com/SGlVs.jpg" alt="enter image description here">

How to crop circular area from bitmap in Android

Kotlin

我有一个位图，我想从这个位图裁剪一个圆形区域。圆之外的所有像素都应该是透明的。我该怎么做呢？​​

问如何在Android中从位图中裁剪圆形区域
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