Develop Reference

Android: Circular Drawable

I made this Custom Drawable that should clip any Drawable in circle. But with my implementation, the drawable passed is being the output in the original form not in the circular form.
public class CircularDrawable extends Drawable {
Paint mPaint,xfermodePaint;
Drawable mDrawable;
int[] vinylCenter = new int[2];
int radius;
Bitmap src;
PorterDuffXfermode xfermode;
Rect rect;
Canvas testCanvas;
public CircularDrawable(Drawable drawable) {
mDrawable = drawable;
mPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
mPaint.setColor(0xffffffff);
mPaint.setStyle(Paint.Style.FILL);
xfermodePaint = new Paint(Paint.ANTI_ALIAS_FLAG);
xfermode=new PorterDuffXfermode(PorterDuff.Mode.SRC_IN);
xfermodePaint.setXfermode(xfermode);
testCanvas=new Canvas();
}
#Override
public void setBounds(Rect bounds) {
super.setBounds(bounds);
mDrawable.setBounds(bounds);
}
#Override
public void setBounds(int left, int top, int right, int bottom) {
super.setBounds(left, top, right, bottom);
mDrawable.setBounds(left, top, right, bottom);
}
#Override
protected void onBoundsChange(Rect bounds) {
super.onBoundsChange(bounds);
vinylCenter[0] = bounds.width() / 2;
vinylCenter[1] = bounds.height() / 2;
radius = (bounds.right - bounds.left) / 2;
src = Bitmap.createBitmap(bounds.width(), bounds.height(), Bitmap.Config.ARGB_8888);
testCanvas.setBitmap(src);
}
#Override
public void draw(Canvas canvas) {
canvas.save();
canvas.drawARGB(0, 0, 0, 0);
canvas.drawCircle(vinylCenter[0],vinylCenter[1],radius,mPaint);
mDrawable.draw(testCanvas);
canvas.drawBitmap(src,0f,0f,xfermodePaint);
}
#Override
public void setAlpha(int alpha) {/*ignored*/}
#Override
public void setColorFilter(ColorFilter colorFilter) {/*ignored*/}
#Override
public int getOpacity() {
/*ignored*/
return 0;
}
}
What is my mistake?
Also I am using a SquareImageview to display this drawable that just makes the view square in onMeasure.
This question is not meant for Circular imageview.

You already have optimized implementation for circular drawable in Support library v4:
Google reference
/**
* A Drawable that wraps a bitmap and can be drawn with rounded corners. You can create a
* RoundedBitmapDrawable from a file path, an input stream, or from a
* {#link android.graphics.Bitmap} object.
* <p>
* Also see the {#link android.graphics.Bitmap} class, which handles the management and
* transformation of raw bitmap graphics, and should be used when drawing to a
* {#link android.graphics.Canvas}.
* </p>
*/
public abstract class RoundedBitmapDrawable extends Drawable ....

The canvas doesnt have alpha channel on by default when using Porter/Duff xfermode mode (As per my experience with my this in android). That is the reason the whole image(src) is being the output. Porter/Duff xfermode acts based on Alpha Channel.
In many implementation of Circular Drawable 2 Canvas are taken, out of which one is given RGB image bitmap and other is given only alpha channel bitmap with circular mask. Porter/Duff xfermodeis applied and the result is drawn on the main canvas.
My mistake is that I am not specifying the draw function's canvas that alpha channel is to be considered on using the layer on the canvas for xfermode.
The draw function will become
#Override
public void draw(Canvas canvas) {
int sc = canvas.saveLayer(null, null,
Canvas.HAS_ALPHA_LAYER_SAVE_FLAG |
);
canvas.drawCircle(vinylCenter[0],vinylCenter[1],radius,mPaint);
mDrawable.draw(testCanvas);
canvas.drawBitmap(src,0f,0f,xfermodePaint);
canvas.restoreToCount(sc);
}
Saving the Layer to indicate alpha channel with the flag and then using the xfermode. Finally restoring it to its save count.

So basically I use this method to get rounded corner images
public static Bitmap getRoundedCornerBitmap(Bitmap bitmap, int pixels) {
Bitmap output = Bitmap.createBitmap(bitmap.getWidth(), bitmap.getHeight(), 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());
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(PorterDuff.Mode.SRC_IN));
canvas.drawBitmap(bitmap, rect, rect, paint);
return output;
but like you pointed out sometimes it does not work, well it does work, but what happens most of the time is your imageview might have its scaletype set to centerCrop and other types, what I do is I first compress my image height to the same height and width as my imageview so that the entire image will fit in the imageview and no scaling will take place or I just calculate how much of the corner height to make rounded using this function based on the height
private int calculatePercentage(int percentage, int target)
{
int k = (int)(target*(percentage/100.0f));
return k;
}
so I use my code like: new Bitmap(getRoundedCornerBitmap(bmp, calculatePercentage(5, bmp.getHeight()))); where 5 is 5 of the image height this gives me same curves for all images be it some images are bigger than others
`

For rounded imageview you can use this code
public class RoundedImageView extends ImageView {
public RoundedImageView(Context context) {
super(context);
// TODO Auto-generated constructor stub
}
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) {
Drawable drawable = getDrawable();
if (drawable == null) {
return;
}
if (getWidth() == 0 || getHeight() == 0) {
return;
}
Bitmap b = ((BitmapDrawable) drawable).getBitmap();
Bitmap bitmap = b.copy(Bitmap.Config.ARGB_8888, true);
int w = getWidth();//, h = getHeight();
Bitmap roundBitmap = getCroppedBitmap(bitmap, w);
canvas.drawBitmap(roundBitmap, 0, 0, null);
}
public static Bitmap getCroppedBitmap(Bitmap bmp, int radius)
{
Bitmap sbmp;
if (bmp.getWidth() != radius || bmp.getHeight() != radius)
sbmp = Bitmap.createScaledBitmap(bmp, radius, radius, false);
else
sbmp = bmp;
Bitmap output = Bitmap.createBitmap(sbmp.getWidth(), sbmp.getHeight(),Config.ARGB_8888);
Canvas canvas = new Canvas(output);
// final int color = 0xffa19774;
final Paint paint = new Paint();
final Rect rect = new Rect(0, 0, sbmp.getWidth(), sbmp.getHeight());
paint.setAntiAlias(true);
paint.setFilterBitmap(true);
paint.setDither(true);
canvas.drawARGB(0, 0, 0, 0);
// paint.setColor(Color.parseColor("#BAB399"));
paint.setColor(Color.parseColor("#FF0000"));
canvas.drawCircle(sbmp.getWidth() / 2 + 0.7f, sbmp.getHeight() / 2 + 0.7f, sbmp.getWidth() / 2 + 0.1f, paint);
paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN));
canvas.drawBitmap(sbmp, rect, rect, paint);
return output;
}
}

For circular imageview use the below code
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) {
BitmapDrawable drawable = (BitmapDrawable) getDrawable();
if (drawable == null) {
return;
}
if (getWidth() == 0 || getHeight() == 0) {
return;
}
Bitmap fullSizeBitmap = drawable.getBitmap();
int scaledWidth = getMeasuredWidth();
int scaledHeight = getMeasuredHeight();
/*
* scaledWidth = scaledWidth/2; scaledHeight = scaledHeight/2;
*/
Bitmap mScaledBitmap;
if (scaledWidth == fullSizeBitmap.getWidth()
&& scaledHeight == fullSizeBitmap.getHeight()) {
mScaledBitmap = fullSizeBitmap;
} else {
mScaledBitmap = Bitmap.createScaledBitmap(fullSizeBitmap,
scaledWidth, scaledHeight, true /* filter */);
}
// Bitmap roundBitmap = getRoundedCornerBitmap(mScaledBitmap);
// Bitmap roundBitmap = getRoundedCornerBitmap(getContext(),
// mScaledBitmap, 10, scaledWidth, scaledHeight, false, false,
// false, false);
// canvas.drawBitmap(roundBitmap, 0, 0, null);
Bitmap circleBitmap = getCircledBitmap(mScaledBitmap);
canvas.drawBitmap(circleBitmap, 0, 0, null);
}
public Bitmap getRoundedCornerBitmap(Context context, Bitmap input,
int pixels, int w, int h, boolean squareTL, boolean squareTR,
boolean squareBL, boolean squareBR) {
Bitmap output = Bitmap.createBitmap(w, h, Config.ARGB_8888);
Canvas canvas = new Canvas(output);
final float densityMultiplier = context.getResources()
.getDisplayMetrics().density;
final int color = 0xff424242;
final Paint paint = new Paint();
final Rect rect = new Rect(0, 0, w, h);
final RectF rectF = new RectF(rect);
// make sure that our rounded corner is scaled appropriately
final float roundPx = pixels * densityMultiplier;
paint.setAntiAlias(true);
canvas.drawARGB(0, 0, 0, 0);
paint.setColor(color);
canvas.drawRoundRect(rectF, roundPx, roundPx, paint);
// draw rectangles over the corners we want to be square
if (squareTL) {
canvas.drawRect(0, 0, w / 2, h / 2, paint);
}
if (squareTR) {
canvas.drawRect(w / 2, 0, w, h / 2, paint);
}
if (squareBL) {
canvas.drawRect(0, h / 2, w / 2, h, paint);
}
if (squareBR) {
canvas.drawRect(w / 2, h / 2, w, h, paint);
}
paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_IN));
canvas.drawBitmap(input, 0, 0, paint);
return output;
}
Bitmap getCircledBitmap(Bitmap bitmap) {
Bitmap result = Bitmap.createBitmap(bitmap.getWidth(),
bitmap.getHeight(), Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(result);
int color = Color.BLUE;
Paint paint = new Paint();
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.getHeight() / 2, paint);
paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN));
canvas.drawBitmap(bitmap, rect, rect, paint);
return result;
}
}

Try disabling hardware acceleration if you are using PorterDuffXfermode:
In manifest for whole activity:
<activity android:hardwareAccelerated="false" />
Or on a specific view on which you are using xfermode:
myView.setLayerType(View.LAYER_TYPE_SOFTWARE, null);

Skew matrix in Android

I'm working on Android project. and I'm using View class to drawing bitmap using canvas with matrix.
How can I skew matrix? to be like this:
I'm using this code, but it is not working:
float[] src=new float[]{0,0,0,1,1,1,1,0};
float[] dst=new float[]{0.2f,0,0,1,1,1,0.8f,0};
Paint paint = new Paint();
matrix.reset();
matrix.postTranslate(-width / 2.0f, -height / 2.0f);
matrix.postRotate(0/*(float)(angle*180/Math.PI) ,-width / 2.0f + 50, -height / 2.0f +50*/);
matrix.postScale(scale, scale);
matrix.setPolyToPoly(src, 0, dst, 0, 4);
matrix.postTranslate(position.getX(), position.getY());
canvas.drawBitmap(bitmap, matrix, paint);
canvas.concat(matrix);

use something like this:
class V extends View {
private Bitmap b;
private Matrix m;
public V(Context context) {
super(context);
b = BitmapFactory.decodeResource(getResources(), R.drawable.layer0);
m = new Matrix();
}
#Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
int bw = b.getWidth();
int bh = b.getHeight();
float[] src = {0, 0, 0, bh, bw, bh, bw, 0};
int DX = 100;
float[] dst = {0 + DX, 0, 0, h, w, h, w - DX, 0};
m.setPolyToPoly(src, 0, dst, 0, 4);
}
#Override
protected void onDraw(Canvas canvas) {
canvas.drawBitmap(b, m, null);
}
}
UPDATE to keep the image aspect ratio:
#Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
int bw = b.getWidth();
int bh = b.getHeight();
RectF src = new RectF(0, 0, bw, bh);
RectF dst = new RectF(0, 0, w, h);
m.setRectToRect(src, dst, ScaleToFit.CENTER);
float[] pts = {0, 0, 0, bh, bw, bh, bw, 0, 0, 0, 0, 0, 0, 0, 0, 0};
m.mapPoints(pts, 8, pts, 0, 4);
int DX = 40;
pts[8] += DX;
pts[14] -= DX;
m.setPolyToPoly(pts, 0, pts, 8, 4);
}

Android circular border around circular image

I do this to get a circular ImageView, how can I add a circle border around it like this picture:
public static Bitmap getRoundedShape(Bitmap scaleBitmapImage,int width) {
int targetWidth = width;
int targetHeight = width;
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), null);
return targetBitmap;
}

There is a very interesting post about this feature:
http://www.curious-creature.org/2012/12/11/android-recipe-1-image-with-rounded-corners/
It is written by Romain Guy (ex android team at Google).
You can use something like this:
This example create a circular bitmap, with around a white stroke.
You can change it, adding a white stroke with a black line.
public class CircleDrawable extends Drawable {
private final BitmapShader mBitmapShader;
private final Paint mPaint;
private Paint mWhitePaint;
int circleCenterX;
int circleCenterY;
int mRadus;
private boolean mUseStroke = false;
private int mStrokePadding = 0;
public CircleDrawable(Bitmap bitmap) {
mBitmapShader = new BitmapShader(bitmap,
Shader.TileMode.CLAMP, Shader.TileMode.CLAMP);
mPaint = new Paint();
mPaint.setAntiAlias(true);
mPaint.setShader(mBitmapShader);
}
public CircleDrawable(Bitmap bitmap, boolean mUseStroke) {
this(bitmap);
if (mUseStroke) {
this.mUseStroke = true;
mStrokePadding = 4;
mWhitePaint = new Paint();
mWhitePaint.setStyle(Paint.Style.FILL_AND_STROKE);
mWhitePaint.setStrokeWidth(0.75f);
mWhitePaint.setColor(Color.WHITE);
}
}
#Override
protected void onBoundsChange(Rect bounds) {
super.onBoundsChange(bounds);
circleCenterX = bounds.width() / 2;
circleCenterY = bounds.height() / 2;
if (bounds.width() >= bounds.height())
mRadus = bounds.width() / 2;
else
mRadus = bounds.height() / 2;
}
#Override
public void draw(Canvas canvas) {
if (mUseStroke) {
canvas.drawCircle(circleCenterX, circleCenterY, mRadus, mWhitePaint);
}
canvas.drawCircle(circleCenterX, circleCenterY, mRadus - mStrokePadding, mPaint);
}
#Override
public int getOpacity() {
return PixelFormat.TRANSLUCENT;
}
#Override
public void setAlpha(int alpha) {
mPaint.setAlpha(alpha);
}
#Override
public void setColorFilter(ColorFilter cf) {
mPaint.setColorFilter(cf);
}
public boolean ismUseStroke() {
return mUseStroke;
}
public void setmUseStroke(boolean mUseStroke) {
this.mUseStroke = mUseStroke;
}
}

Draw and fill custom shape

I'm trying to create a custom shape using the Path object in Android and I'm running into a weird problem.
What I'm trying to achieve is depicted in the picture below
Here is the code I'm using to draw and fill the shape:
public class BallView extends RelativeLayout {
....
protected void onDraw(Canvas canvas) {
...
PaintArc(canvas);
}
private void PaintArc(Canvas canvas) {
Paint p = new Paint(Paint.ANTI_ALIAS_FLAG);
p.setAntiAlias(true);
p.setStyle(Paint.Style.FILL_AND_STROKE);
p.setStrokeWidth(2);
p.setColor(Color.RED);
RectF oval = new RectF(20, 20, getWidth() - 20, getHeight() - 20);
RectF oval2 = new RectF(0, 0, getWidth(), getHeight());
Path path = new Path();
path.setFillType(Path.FillType.EVEN_ODD);
path.addArc(oval, 0, 180);
path.addArc(oval2, 0, 180);
float y=20+oval.height()/2;
float x=20;
path.moveTo(x,y);
path.lineTo(x - 20, y);
x=oval.width()+20;
path.moveTo(x,y);
path.lineTo(x+20,y);
path.close();
canvas.drawPath(path, p);
}
}
The actual result that I'm getting looks like this:
The resulting shape without Filling looks like this:
Can you tell me what I'm doing wrong ?

try this:
class MyView extends View {
private Path mPath;
private Paint mPaint;
private RectF mOval;
public MyView(Context context) {
super(context);
mPath = new Path();
mPaint = new Paint();
mPaint.setColor(0xffff0000);
mOval = new RectF();
}
#Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
int dx = w / 4;
mOval.set(0, 0, w, w);
mPath.reset();
mPath.moveTo(0, w / 2f);
mPath.arcTo(mOval, 180, 180);
mPath.rLineTo(-dx, 0);
mOval.inset(dx, dx);
mPath.addArc(mOval, 0, -180);
mPath.rLineTo(-dx, 0);
}
#Override
protected void onDraw(Canvas canvas) {
canvas.drawColor(0xffffffff);
mPaint.setStyle(Style.FILL);
canvas.drawPath(mPath, mPaint);
canvas.translate(0, getWidth() / 2);
mPaint.setStyle(Style.STROKE);
canvas.drawPath(mPath, mPaint);
}
}

- I have just edited my answer
and i add below code
RectF oval3 = new RectF(10, 20, getWidth() - 10, getHeight() - 10);
/**
*Now check this code output seem like your thought
*/
private void PaintArc(Canvas canvas) {
Paint p = new Paint(Paint.ANTI_ALIAS_FLAG);
p.setAntiAlias(true);
p.setStyle(Paint.Style.STROKE);
p.setStrokeWidth(2);
p.setColor(Color.RED);
Paint p1 = new Paint(Paint.ANTI_ALIAS_FLAG);
p1.setAntiAlias(true);
p1.setStyle(Paint.Style.STROKE);
p1.setStrokeWidth(10);
p1.setColor(Color.RED);
RectF oval = new RectF(20, 20, getWidth() - 20, getHeight() - 20);
RectF oval2 = new RectF(0, 0, getWidth(), getHeight());
RectF oval3 = new RectF(10, 20, getWidth() - 10, getHeight() - 10);
Path path = new Path();
path.setFillType(Path.FillType.EVEN_ODD);
path.addArc(oval, 0, 180);
path.addArc(oval2, 0, 180);
path.addArc(oval3, 0, 180);
float y = 20 + oval.height() / 2;
float x = 20;
path.moveTo(x, y);
path.lineTo(x - 20, y);
x = oval.width() + 20;
path.moveTo(x, y);
path.lineTo(x + 20, y);
path.close();
canvas.drawArc(oval3, 0, 180, false, p1);
canvas.drawPath(path, p);
}

Drawing 2 circles on a canvas

I'm trying to draw two circles like this:
This is how I'm trying to do it:
Bitmap bmp = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_4444);
Canvas c = new Canvas(bmp);
RectF rect = new RectF(0,0,width,width);
Paint paint = new Paint();
drawCircles(paint, c, width, height, width);
ImageView img = (ImageView) findViewById(R.id.imageView1);
img.setImageBitmap(bmp);
img.setScaleType(ScaleType.FIT_CENTER);
And here is my drawCircles() method:
private void drawCircles(Paint paint, Canvas c, int width, int height, int radius) {
paint.setARGB(255, 255 , 10, 21);
paint.setStrokeWidth(10);
paint.setAntiAlias(true);
paint.setStrokeCap(Paint.Cap.BUTT);
paint.setStyle(Paint.Style.STROKE);
if(width < height && radius == 0){
radius = width/2;
height = width;
} else if (radius == 0){
radius = height/2;
width = height;
}
Paint paint2 = new Paint();
paint2.setARGB(255, 255 , 10, 21);
paint2.setStrokeWidth(10);
paint2.setAntiAlias(true);
paint2.setStrokeCap(Paint.Cap.BUTT);
paint2.setStyle(Paint.Style.STROKE);
c.drawCircle(width/2, height/2, radius-10, paint);
c.drawCircle(width/2, height/2, 50, paint2);
}
I don't know why but I get only one circle, the small one (the one drawn with paint2).
What can be the reason?

Try this code.Hope it may helps :)
public class SimpleCircleActivity extends Activity
{
private CircleDemoView circledemoView ;
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
circledemoView =new CircleDemoView(this);
setContentView(circledemoView);
}
private class CircleDemoView extends View
{
public CircleDemoView(Context context)
{
super(context);
}
#Override
protected void onDraw(Canvas canvas)
{
super.onDraw(canvas);
Paint p = new Paint();
p.setColor(Color.RED);
DashPathEffect dashPath = new DashPathEffect(new float[]{5,5}, (float)1.0);
p.setPathEffect(dashPath);
p.setStyle(Style.STROKE);
for (int i = 0; i < 2; i ++) {
canvas.drawCircle(200, 200, 50+(i*40), p);
}
invalidate();
}
}
}