I'm developing a function to draw a rounded button in my android application. The problem is that the final results is rectangular instead of something rounded on the corners. What am I missing?
fun draw(canvas: Canvas?) {
canvas?.let {
if (strokeColor != -1) {
shaderBorderPaint.color = strokeColor
shaderBorderPaint.shader = null
} else {
shaderBorderPaint.shader = shaderFactory.resize(it.width, it.height)
}
val cornerRadius = 8f
val halfStrokeSize: Float = shaderBorderPaint.strokeWidth / 2
val rect = RectF(halfStrokeSize, it.height - halfStrokeSize, it.width - halfStrokeSize, halfStrokeSize)
it.drawRoundRect(rect, cornerRadius, cornerRadius, shaderBorderPaint)
}
}
Try this instead.
val corners = floatArrayOf(
80f, 80f, // Top left radius in px
80f, 80f, // Top right radius in px
0f, 0f, // Bottom right radius in px
0f, 0f // Bottom left radius in px
)
val path = Path()
path.addRoundRect(rect, corners, Path.Direction.CW)
canvas.drawPath(path, mPaint)
or this,
public static void makeRoundCorner(int bgcolor,int radius,View v,int strokeWidth,int strokeColor)
{
GradientDrawable gdDefault = new GradientDrawable();
gdDefault.setColor(bgcolor);
gdDefault.setCornerRadius(radius);
gdDefault.setStroke(strokeWidth, strokeColor);
v.setBackgroundDrawable(gdDefault);
}
because val cornerRadius = 8f. try to set cornerRadius = heightRect / 2
Related
I'm using canvas to draw a circle and border. The circle fill color and border color are different. I'm also drawing a text in the center of the circle. But the problem I'm facing is that the edges on all four sides of the circle seems to be cut off.
This is the code I'm using for drawing the circle, border and text.
override fun onDraw(canvas: Canvas) {
super.onDraw(canvas)
try {
/** Draw Circle **/
drawPaint.color = ContextCompat.getColor(context, R.color.white_static)
drawPaint.style = Paint.Style.FILL
canvas.drawCircle(size, size, size, drawPaint)
/** Draw Border **/
borderPaint.color = ContextCompat.getColor(context, R.color.color_primary)
borderPaint.style = Paint.Style.STROKE
borderPaint.strokeJoin = Paint.Join.ROUND
borderPaint.strokeWidth = 2f
canvas.drawCircle(size, size, size, borderPaint)
/** Draw Text **/
textPaint.textAlign = Paint.Align.CENTER
textPaint.color = ContextCompat.getColor(context, R.color.color_primary)
val xPos = width / 2
val yPos = (height / 2 - (textPaint.descent() + textPaint.ascent()) / 2).toInt()
/** Add Text **/
canvas.drawText(text!!, xPos.toFloat(), yPos.toFloat(), textPaint)
} catch (e: Exception) {
println("CircularTextView => Exception caught => $e")
}
}
I need to draw a circle and fill it according to a percentage value as image shows.
]2
I have tried to draw it using canvas:
#SuppressLint("DrawAllocation")
override fun onDraw(canvas: Canvas?) {
super.onDraw(canvas)
rectF = RectF(0f + margin, 0f + margin, width.toFloat() - margin, height.toFloat() - margin)
val scaledValues = scale()
var sliceStartPoint = 0F
for (i in scaledValues.indices) {
slicePaint.color = ContextCompat.getColor(context, sliceColors[i])
canvas!!.drawArc(rectF!!, sliceStartPoint, scaledValues[i], true, slicePaint)
canvas.drawArc(rectF!!, sliceStartPoint, scaledValues[i], true, centerPaint)
sliceStartPoint += scaledValues[i]
}
}
The problem is that I got all lines centered to radio (as a Pie) instead of slices.
I tried to set usecenter:false but it was not successful result.
Any idea how to draw an arc without set the center point as vertice?
I think you just need rotate the canvas & a little math.
private val slicePaint = Paint()
private val centerPaint = Paint().apply {
color = 0x33333333
}
private val sliceColors = arrayListOf<Int>(Color.GRAY, Color.RED, Color.BLACK)
private var rectF: RectF? = null
private val margin = 0f
private var rotDeg = -120f
override fun onDraw(canvas: Canvas) {
super.onDraw(canvas)
rectF = RectF(0f + margin, 0f + margin, width.toFloat() - margin, height.toFloat() - margin)
canvas.save()
canvas.rotate(rotDeg, canvas.width /2.0f, canvas.height/2.0f)
// val scaledValues = scale()
// var sliceStartPoint = 0F
for (i in percent.indices) {
slicePaint.color = sliceColors[i] // ContextCompat.getColor(context, sliceColors[i])
var d = percent2degree(percent[i])
canvas!!.drawArc(rectF!!, d, -2 * d, false, slicePaint)
// canvas.drawArc(rectF!!, sliceStartPoint, scaledValues[i], true, centerPaint)
// sliceStartPoint += scaledValues[i]
}
canvas.restore()
}
private fun percent2degree(p:Float): Float {
return (acos((0.5 - p)/ 0.5) / Math.PI * 180).toFloat()
}
var percent = arrayOf(1.0f, 0.9f, 0.55f) // 0.5 + 0.3 + 0.2 = 100%
How to use canvas to draw a selected field of transparent color with blue background?
In official documentation i find smth like this .
But there is still a question of how to implement it.
Also for example, i tried to draw line:
private fun someFun(canvas: Canvas, parent: RecyclerView) {
val radius: Float = parent.context.resources.getDimension(R.dimen.dimen_12)
val paint = Paint()
paint.color = ContextCompat.getColor(parent.context, R.color.primary)
paint.style = Paint.Style.FILL
val path = Path()
path.moveTo(0f, 0f)
path.lineTo(0f, radius)
path.arcTo(RectF(0f, 0f, radius * 2, radius * 2), 270f, -90f)
path.close()
canvas.drawPath(path, paint)
}
And get smth like this:
Decided to the next way:
private fun drawRoundedCorners(canvas: Canvas, parent: RecyclerView) {
val radius: Float = parent.context.resources.getDimension(R.dimen.dimen_12)
val paint = Paint()
paint.color = ContextCompat.getColor(parent.context, R.color.primary)
paint.style = Paint.Style.FILL
val path = Path()
path.moveTo(0f, 0f)
path.lineTo(150f, 0f)
path.arcTo(RectF(0f, 0f, radius * 2, radius * 2), 270f, -90f)
path.moveTo(parent.width.toFloat(), 0f)
path.lineTo(parent.width.toFloat(), 0f)
path.arcTo(RectF(parent.width.toFloat() - radius * 2, 0f, parent.width.toFloat(),
radius * 2), 270f, 90f)
path.close()
canvas.drawPath(path, paint)
}
What i have:: I have a Imageview for which i am making image as a circle using picassso
What i what to do:: I want to add a black border for rounded image using my current implementation, how to achieve this without using third party library
Picasso.with(this)
.load("http://i.imgur.com/DvpvklR.png")
.transform(new RoundedTransformation(50, 4))
.resize(100, 100)
.centerCrop().into(imageView1);
RoundedTransformation.java
// enables hardware accelerated rounded corners
// original idea here : http://www.curious-creature.org/2012/12/11/android-recipe-1-image-with-rounded-corners/
public class RoundedTransformation implements com.squareup.picasso.Transformation {
private final int radius;
private final int margin; // dp
// radius is corner radii in dp
// margin is the board in dp
public RoundedTransformation(final int radius, final int margin) {
this.radius = radius;
this.margin = margin;
}
#Override
public Bitmap transform(final Bitmap source) {
final Paint paint = new Paint();
paint.setAntiAlias(true);
paint.setShader(new BitmapShader(source, Shader.TileMode.CLAMP, Shader.TileMode.CLAMP));
Bitmap output = Bitmap.createBitmap(source.getWidth(), source.getHeight(), Config.ARGB_8888);
Canvas canvas = new Canvas(output);
canvas.drawRoundRect(new RectF(margin, margin, source.getWidth() - margin, source.getHeight() - margin), radius, radius, paint);
if (source != output) {
source.recycle();
}
return output;
}
#Override
public String key() {
return "rounded";
}
}
EDIT
public class RoundedTransformation implements com.squareup.picasso.Transformation {
private final int radius;
private final int margin; // dp
// radius is corner radii in dp
// margin is the board in dp
public RoundedTransformation(final int radius, final int margin) {
this.radius = radius;
this.margin = margin;
}
#Override
public Bitmap transform(final Bitmap source) {
final Paint paint = new Paint();
paint.setAntiAlias(true);
paint.setShader(new BitmapShader(source, Shader.TileMode.CLAMP, Shader.TileMode.CLAMP));
Bitmap output = Bitmap.createBitmap(source.getWidth(), source.getHeight(), Config.ARGB_8888);
Canvas canvas = new Canvas(output);
canvas.drawRoundRect(new RectF(margin, margin, source.getWidth() - margin, source.getHeight() - margin), radius, radius, paint);
if (source != output) {
source.recycle();
}
Paint paint1 = new Paint();
paint1.setColor(Color.RED);
paint1.setStyle(Style.STROKE);
paint1.setAntiAlias(true);
paint1.setStrokeWidth(2);
canvas.drawCircle((source.getWidth() - margin)/2, (source.getHeight() - margin)/2, radius-2, paint1);
return output;
}
#Override
public String key() {
return "rounded";
}
}
Final transformation class, thanks to blackbelt
public class RoundedTransformation implements com.squareup.picasso.Transformation {
private final int radius;
private final int margin; // dp
// radius is corner radii in dp
// margin is the board in dp
public RoundedTransformation(final int radius, final int margin) {
this.radius = radius;
this.margin = margin;
}
#Override
public Bitmap transform(final Bitmap source) {
final Paint paint = new Paint();
paint.setAntiAlias(true);
paint.setShader(new BitmapShader(source, Shader.TileMode.CLAMP, Shader.TileMode.CLAMP));
Bitmap output = Bitmap.createBitmap(source.getWidth(), source.getHeight(), Config.ARGB_8888);
Canvas canvas = new Canvas(output);
canvas.drawCircle((source.getWidth() - margin)/2, (source.getHeight() - margin)/2, radius-2, paint);
if (source != output) {
source.recycle();
}
Paint paint1 = new Paint();
paint1.setColor(Color.RED);
paint1.setStyle(Style.STROKE);
paint1.setAntiAlias(true);
paint1.setStrokeWidth(2);
canvas.drawCircle((source.getWidth() - margin)/2, (source.getHeight() - margin)/2, radius-2, paint1);
return output;
}
#Override
public String key() {
return "rounded";
}
}
you can use drawCircle with another Paint object. For instance:
Paint paint = new Paint();
paint.setColor(Color.RED);
paint.setStyle(Style.STROKE);
paint.setAntiAlias(true);
paint.setStrokeWidth(2);
canvas.drawCircle((source.getWidth() - margin)/2, (source.getHeight() - margin)/2, radius-2, paint);
Also, instead of using a drawRoundRect to draw a circle, you can use drawCircle
Answers of BlackBelt and Devrath are great. And if you are looking for a Kotlin version of this class, here it is:
class RoundedBorderTransform(private val radius: Int, private val margin: Int) : com.squareup.picasso.Transformation {
override fun transform(source: Bitmap?): Bitmap {
val paint = Paint()
paint.isAntiAlias = true
paint.shader = BitmapShader(source!!, Shader.TileMode.CLAMP, Shader.TileMode.CLAMP)
val output = Bitmap.createBitmap(source.width, source.height, Bitmap.Config.ARGB_8888)
val canvas = Canvas(output)
canvas.drawCircle((source.width - margin) / 2f, (source.height - margin) / 2f, radius - 2f, paint)
if (source != output) {
source.recycle()
}
val borderPaint = Paint()
borderPaint.color = Color.RED
borderPaint.style = Paint.Style.STROKE
borderPaint.isAntiAlias = true
borderPaint.strokeWidth = 2f
canvas.drawCircle((source.width - margin) / 2f, (source.height - margin) / 2f, radius - 2f, borderPaint)
return output
}
override fun key(): String {
return "roundedBorder"
}
}
This is solution for circle and rectangle shapes. Also it's useful not only for Picasso usage, but for general android Canvas-tasks.
I've created them very voluminous and detailed only for yours understanding of processes, shorten as you want.
But I want to clarify a main problem that many people faced with.
In android there no possibilities to create inner or outer border - only centered:
And this is the reason why you receive border elements cut off like these:
So there only a single way to recalculate position of border: in case of
circle you have to decrease circle radius by HALF OF BORDER WIDTH
rectangle you have to 1) shift border lines "inside" by HALF OF BORDER WIDTH; 2) decrease corner radius by HALF OF BORDER WIDTH
These actions will provide you an expected results:
If you're need only code for you border - pick only correspondent drawBorder() method.
Here is an example for empty Fragment with two images:
ViewsCroppingAndBorderingTestFragment.kt
class ViewsCroppingAndBorderingTestFragment : Fragment() {
override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
return inflater.inflate(R.layout.fragment_test_views_cropping_and_bordering, container, false)
}
override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
super.onViewCreated(view, savedInstanceState)
val urlCircle = "https://images-na.ssl-images-amazon.com/images/I/71zLQIfmTlL._AC_SX466_.jpg"
val urlRectRounded = "https://www.gardendesign.com/pictures/images/675x529Max/site_3/helianthus-yellow-flower-pixabay_11863.jpg"
val ivCircle = view.findViewById<ImageView>(R.id.ivCircle)
val ivRectRounded = view.findViewById<ImageView>(R.id.ivRectRounded)
val trCircle = CircleTransformation()
val trRectRounded = RectRoundedTransformation()
Picasso.get().load(urlCircle).transform(trCircle).into(ivCircle)
Picasso.get().load(urlRectRounded).transform(trRectRounded).into(ivRectRounded)
}
class CircleTransformation() : Transformation {
override fun transform(source: Bitmap): Bitmap {
val size = Math.min(source.width, source.height)
val x = (source.width - size) / 2
val y = (source.height - size) / 2
val w = size
val h = size
val squaredBitmap = Bitmap.createBitmap(source, x, y, w, h)
if (squaredBitmap != source) {
source.recycle()
}
val bitmap = Bitmap.createBitmap(w, h, source.config)
val canvas = Canvas(bitmap)
// >> Draw original rectangle image
// val paint = Paint(Paint.ANTI_ALIAS_FLAG)
// canvas.drawBitmap(squaredBitmap, 0F, 0F, paint)
val rImage = w / 2f
cropWithCircle(squaredBitmap, canvas, rImage)
squaredBitmap.recycle()
drawBorder(canvas, rImage)
return bitmap
}
private fun cropWithCircle(bitmapSource: Bitmap, canvas: Canvas, rImage: Float) {
val shader = BitmapShader(bitmapSource, Shader.TileMode.CLAMP, Shader.TileMode.CLAMP)
val paint = Paint(Paint.ANTI_ALIAS_FLAG)
paint.shader = shader
paint.isAntiAlias = true
val xCenter = rImage
val yCenter = rImage
canvas.drawCircle(xCenter, yCenter, rImage, paint)
}
private fun drawBorder(canvas: Canvas, rImage: Float) {
val borderWidth = 30F
val paintBorder = Paint()
paintBorder.strokeWidth = borderWidth
paintBorder.style = Paint.Style.STROKE
paintBorder.color = Color.GREEN
paintBorder.isAntiAlias = true
val cCenter = rImage
val yCenter = rImage
// ANDROID'S BORDER IS ALWAYS CENTERED.
// So have to reduce radius by half of border's width
val rBorder = rImage - borderWidth / 2
canvas.drawCircle(cCenter, yCenter, rBorder, paintBorder)
}
override fun key(): String {
return "circle"
}
}
class RectRoundedTransformation() : Transformation {
override fun transform(source: Bitmap): Bitmap {
val x = 0
val y = 0
val w = source.width
val h = source.height
val squaredBitmap = Bitmap.createBitmap(source, x, y, w, h)
if (squaredBitmap != source) {
source.recycle()
}
val bitmap = Bitmap.createBitmap(w, h, source.config)
val canvas = Canvas(bitmap)
// >> Draw original rectangle image
// val paint = Paint(Paint.ANTI_ALIAS_FLAG)
// canvas.drawBitmap(squaredBitmap, 0F, 0F, paint)
val rCorner = 80F
cropCorners(squaredBitmap, canvas, rCorner)
squaredBitmap.recycle()
drawBorder(canvas, rCorner)
return bitmap
}
private fun cropCorners(bitmapSource: Bitmap, canvas: Canvas, rCorner: Float) {
val width = canvas.width
val height = canvas.height
val maskBitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ALPHA_8)
val maskCanvas = Canvas(maskBitmap)
val maskPaint = Paint(Paint.ANTI_ALIAS_FLAG)
val maskRect = RectF(0F, 0F, width.toFloat(), height.toFloat())
// 1. draw base rect
maskCanvas.drawRect(maskRect, maskPaint)
// 2. cut off inner rounded rect, leave corners
maskPaint.xfermode = PorterDuffXfermode(PorterDuff.Mode.CLEAR)
maskCanvas.drawRoundRect(maskRect, rCorner, rCorner, maskPaint)
// 3. draw original rectangle image
val paintSource = Paint(Paint.ANTI_ALIAS_FLAG)
canvas.drawBitmap(bitmapSource, 0f, 0f, paintSource)
// 4.cut off corners
val paintCropped = Paint(Paint.ANTI_ALIAS_FLAG or Paint.FILTER_BITMAP_FLAG)
paintCropped!!.xfermode = PorterDuffXfermode(PorterDuff.Mode.CLEAR)
canvas.drawBitmap(maskBitmap!!, 0f, 0f, paintCropped)
}
private fun drawBorder(canvas: Canvas, rCorner: Float) {
val borderWidth = 30F
val paintBorder = Paint()
paintBorder.strokeWidth = borderWidth
paintBorder.style = Paint.Style.STROKE
paintBorder.color = Color.RED
paintBorder.isAntiAlias = true
// // ANDROID'S BORDER IS ALWAYS CENTERED.
// // So have to shift every side by half of border's width
val rectLeft = 0 + borderWidth / 2
val rectTop = 0 + borderWidth / 2
val rectRight = canvas.width.toFloat() - borderWidth / 2
val rectBottom = canvas.height.toFloat() - borderWidth / 2
val rectF = RectF(rectLeft, rectTop, rectRight, rectBottom)
// // So have to corner reduce radius by half of border's width
val rectRCorner = rCorner - borderWidth / 2
canvas.drawRoundRect(rectF, rectRCorner, rectRCorner, paintBorder)
}
override fun key(): String {
return "rectRounded"
}
}
}
fragment_test_views_cropping_and_bordering.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/temp"
android:orientation="horizontal"
android:layout_width="match_parent"
android:layout_height="200dp"
android:paddingLeft="10dp"
android:paddingRight="10dp"
android:background="#android:color/darker_gray">
<ImageView
android:id="#+id/ivCircle"
android:layout_width="150dp"
android:layout_height="150dp"
android:layout_margin="10dp"/>
<ImageView
android:id="#+id/ivRectRounded"
android:layout_width="200dp"
android:layout_height="160dp"
android:layout_margin="10dp"/>
</LinearLayout>
What i have:: I have a Imageview for which i am making image as a circle using picassso
What i what to do:: I want to add a black border for rounded image using my current implementation, how to achieve this without using third party library
Picasso.with(this)
.load("http://i.imgur.com/DvpvklR.png")
.transform(new RoundedTransformation(50, 4))
.resize(100, 100)
.centerCrop().into(imageView1);
RoundedTransformation.java
// enables hardware accelerated rounded corners
// original idea here : http://www.curious-creature.org/2012/12/11/android-recipe-1-image-with-rounded-corners/
public class RoundedTransformation implements com.squareup.picasso.Transformation {
private final int radius;
private final int margin; // dp
// radius is corner radii in dp
// margin is the board in dp
public RoundedTransformation(final int radius, final int margin) {
this.radius = radius;
this.margin = margin;
}
#Override
public Bitmap transform(final Bitmap source) {
final Paint paint = new Paint();
paint.setAntiAlias(true);
paint.setShader(new BitmapShader(source, Shader.TileMode.CLAMP, Shader.TileMode.CLAMP));
Bitmap output = Bitmap.createBitmap(source.getWidth(), source.getHeight(), Config.ARGB_8888);
Canvas canvas = new Canvas(output);
canvas.drawRoundRect(new RectF(margin, margin, source.getWidth() - margin, source.getHeight() - margin), radius, radius, paint);
if (source != output) {
source.recycle();
}
return output;
}
#Override
public String key() {
return "rounded";
}
}
EDIT
public class RoundedTransformation implements com.squareup.picasso.Transformation {
private final int radius;
private final int margin; // dp
// radius is corner radii in dp
// margin is the board in dp
public RoundedTransformation(final int radius, final int margin) {
this.radius = radius;
this.margin = margin;
}
#Override
public Bitmap transform(final Bitmap source) {
final Paint paint = new Paint();
paint.setAntiAlias(true);
paint.setShader(new BitmapShader(source, Shader.TileMode.CLAMP, Shader.TileMode.CLAMP));
Bitmap output = Bitmap.createBitmap(source.getWidth(), source.getHeight(), Config.ARGB_8888);
Canvas canvas = new Canvas(output);
canvas.drawRoundRect(new RectF(margin, margin, source.getWidth() - margin, source.getHeight() - margin), radius, radius, paint);
if (source != output) {
source.recycle();
}
Paint paint1 = new Paint();
paint1.setColor(Color.RED);
paint1.setStyle(Style.STROKE);
paint1.setAntiAlias(true);
paint1.setStrokeWidth(2);
canvas.drawCircle((source.getWidth() - margin)/2, (source.getHeight() - margin)/2, radius-2, paint1);
return output;
}
#Override
public String key() {
return "rounded";
}
}
Final transformation class, thanks to blackbelt
public class RoundedTransformation implements com.squareup.picasso.Transformation {
private final int radius;
private final int margin; // dp
// radius is corner radii in dp
// margin is the board in dp
public RoundedTransformation(final int radius, final int margin) {
this.radius = radius;
this.margin = margin;
}
#Override
public Bitmap transform(final Bitmap source) {
final Paint paint = new Paint();
paint.setAntiAlias(true);
paint.setShader(new BitmapShader(source, Shader.TileMode.CLAMP, Shader.TileMode.CLAMP));
Bitmap output = Bitmap.createBitmap(source.getWidth(), source.getHeight(), Config.ARGB_8888);
Canvas canvas = new Canvas(output);
canvas.drawCircle((source.getWidth() - margin)/2, (source.getHeight() - margin)/2, radius-2, paint);
if (source != output) {
source.recycle();
}
Paint paint1 = new Paint();
paint1.setColor(Color.RED);
paint1.setStyle(Style.STROKE);
paint1.setAntiAlias(true);
paint1.setStrokeWidth(2);
canvas.drawCircle((source.getWidth() - margin)/2, (source.getHeight() - margin)/2, radius-2, paint1);
return output;
}
#Override
public String key() {
return "rounded";
}
}
you can use drawCircle with another Paint object. For instance:
Paint paint = new Paint();
paint.setColor(Color.RED);
paint.setStyle(Style.STROKE);
paint.setAntiAlias(true);
paint.setStrokeWidth(2);
canvas.drawCircle((source.getWidth() - margin)/2, (source.getHeight() - margin)/2, radius-2, paint);
Also, instead of using a drawRoundRect to draw a circle, you can use drawCircle
Answers of BlackBelt and Devrath are great. And if you are looking for a Kotlin version of this class, here it is:
class RoundedBorderTransform(private val radius: Int, private val margin: Int) : com.squareup.picasso.Transformation {
override fun transform(source: Bitmap?): Bitmap {
val paint = Paint()
paint.isAntiAlias = true
paint.shader = BitmapShader(source!!, Shader.TileMode.CLAMP, Shader.TileMode.CLAMP)
val output = Bitmap.createBitmap(source.width, source.height, Bitmap.Config.ARGB_8888)
val canvas = Canvas(output)
canvas.drawCircle((source.width - margin) / 2f, (source.height - margin) / 2f, radius - 2f, paint)
if (source != output) {
source.recycle()
}
val borderPaint = Paint()
borderPaint.color = Color.RED
borderPaint.style = Paint.Style.STROKE
borderPaint.isAntiAlias = true
borderPaint.strokeWidth = 2f
canvas.drawCircle((source.width - margin) / 2f, (source.height - margin) / 2f, radius - 2f, borderPaint)
return output
}
override fun key(): String {
return "roundedBorder"
}
}
This is solution for circle and rectangle shapes. Also it's useful not only for Picasso usage, but for general android Canvas-tasks.
I've created them very voluminous and detailed only for yours understanding of processes, shorten as you want.
But I want to clarify a main problem that many people faced with.
In android there no possibilities to create inner or outer border - only centered:
And this is the reason why you receive border elements cut off like these:
So there only a single way to recalculate position of border: in case of
circle you have to decrease circle radius by HALF OF BORDER WIDTH
rectangle you have to 1) shift border lines "inside" by HALF OF BORDER WIDTH; 2) decrease corner radius by HALF OF BORDER WIDTH
These actions will provide you an expected results:
If you're need only code for you border - pick only correspondent drawBorder() method.
Here is an example for empty Fragment with two images:
ViewsCroppingAndBorderingTestFragment.kt
class ViewsCroppingAndBorderingTestFragment : Fragment() {
override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
return inflater.inflate(R.layout.fragment_test_views_cropping_and_bordering, container, false)
}
override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
super.onViewCreated(view, savedInstanceState)
val urlCircle = "https://images-na.ssl-images-amazon.com/images/I/71zLQIfmTlL._AC_SX466_.jpg"
val urlRectRounded = "https://www.gardendesign.com/pictures/images/675x529Max/site_3/helianthus-yellow-flower-pixabay_11863.jpg"
val ivCircle = view.findViewById<ImageView>(R.id.ivCircle)
val ivRectRounded = view.findViewById<ImageView>(R.id.ivRectRounded)
val trCircle = CircleTransformation()
val trRectRounded = RectRoundedTransformation()
Picasso.get().load(urlCircle).transform(trCircle).into(ivCircle)
Picasso.get().load(urlRectRounded).transform(trRectRounded).into(ivRectRounded)
}
class CircleTransformation() : Transformation {
override fun transform(source: Bitmap): Bitmap {
val size = Math.min(source.width, source.height)
val x = (source.width - size) / 2
val y = (source.height - size) / 2
val w = size
val h = size
val squaredBitmap = Bitmap.createBitmap(source, x, y, w, h)
if (squaredBitmap != source) {
source.recycle()
}
val bitmap = Bitmap.createBitmap(w, h, source.config)
val canvas = Canvas(bitmap)
// >> Draw original rectangle image
// val paint = Paint(Paint.ANTI_ALIAS_FLAG)
// canvas.drawBitmap(squaredBitmap, 0F, 0F, paint)
val rImage = w / 2f
cropWithCircle(squaredBitmap, canvas, rImage)
squaredBitmap.recycle()
drawBorder(canvas, rImage)
return bitmap
}
private fun cropWithCircle(bitmapSource: Bitmap, canvas: Canvas, rImage: Float) {
val shader = BitmapShader(bitmapSource, Shader.TileMode.CLAMP, Shader.TileMode.CLAMP)
val paint = Paint(Paint.ANTI_ALIAS_FLAG)
paint.shader = shader
paint.isAntiAlias = true
val xCenter = rImage
val yCenter = rImage
canvas.drawCircle(xCenter, yCenter, rImage, paint)
}
private fun drawBorder(canvas: Canvas, rImage: Float) {
val borderWidth = 30F
val paintBorder = Paint()
paintBorder.strokeWidth = borderWidth
paintBorder.style = Paint.Style.STROKE
paintBorder.color = Color.GREEN
paintBorder.isAntiAlias = true
val cCenter = rImage
val yCenter = rImage
// ANDROID'S BORDER IS ALWAYS CENTERED.
// So have to reduce radius by half of border's width
val rBorder = rImage - borderWidth / 2
canvas.drawCircle(cCenter, yCenter, rBorder, paintBorder)
}
override fun key(): String {
return "circle"
}
}
class RectRoundedTransformation() : Transformation {
override fun transform(source: Bitmap): Bitmap {
val x = 0
val y = 0
val w = source.width
val h = source.height
val squaredBitmap = Bitmap.createBitmap(source, x, y, w, h)
if (squaredBitmap != source) {
source.recycle()
}
val bitmap = Bitmap.createBitmap(w, h, source.config)
val canvas = Canvas(bitmap)
// >> Draw original rectangle image
// val paint = Paint(Paint.ANTI_ALIAS_FLAG)
// canvas.drawBitmap(squaredBitmap, 0F, 0F, paint)
val rCorner = 80F
cropCorners(squaredBitmap, canvas, rCorner)
squaredBitmap.recycle()
drawBorder(canvas, rCorner)
return bitmap
}
private fun cropCorners(bitmapSource: Bitmap, canvas: Canvas, rCorner: Float) {
val width = canvas.width
val height = canvas.height
val maskBitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ALPHA_8)
val maskCanvas = Canvas(maskBitmap)
val maskPaint = Paint(Paint.ANTI_ALIAS_FLAG)
val maskRect = RectF(0F, 0F, width.toFloat(), height.toFloat())
// 1. draw base rect
maskCanvas.drawRect(maskRect, maskPaint)
// 2. cut off inner rounded rect, leave corners
maskPaint.xfermode = PorterDuffXfermode(PorterDuff.Mode.CLEAR)
maskCanvas.drawRoundRect(maskRect, rCorner, rCorner, maskPaint)
// 3. draw original rectangle image
val paintSource = Paint(Paint.ANTI_ALIAS_FLAG)
canvas.drawBitmap(bitmapSource, 0f, 0f, paintSource)
// 4.cut off corners
val paintCropped = Paint(Paint.ANTI_ALIAS_FLAG or Paint.FILTER_BITMAP_FLAG)
paintCropped!!.xfermode = PorterDuffXfermode(PorterDuff.Mode.CLEAR)
canvas.drawBitmap(maskBitmap!!, 0f, 0f, paintCropped)
}
private fun drawBorder(canvas: Canvas, rCorner: Float) {
val borderWidth = 30F
val paintBorder = Paint()
paintBorder.strokeWidth = borderWidth
paintBorder.style = Paint.Style.STROKE
paintBorder.color = Color.RED
paintBorder.isAntiAlias = true
// // ANDROID'S BORDER IS ALWAYS CENTERED.
// // So have to shift every side by half of border's width
val rectLeft = 0 + borderWidth / 2
val rectTop = 0 + borderWidth / 2
val rectRight = canvas.width.toFloat() - borderWidth / 2
val rectBottom = canvas.height.toFloat() - borderWidth / 2
val rectF = RectF(rectLeft, rectTop, rectRight, rectBottom)
// // So have to corner reduce radius by half of border's width
val rectRCorner = rCorner - borderWidth / 2
canvas.drawRoundRect(rectF, rectRCorner, rectRCorner, paintBorder)
}
override fun key(): String {
return "rectRounded"
}
}
}
fragment_test_views_cropping_and_bordering.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/temp"
android:orientation="horizontal"
android:layout_width="match_parent"
android:layout_height="200dp"
android:paddingLeft="10dp"
android:paddingRight="10dp"
android:background="#android:color/darker_gray">
<ImageView
android:id="#+id/ivCircle"
android:layout_width="150dp"
android:layout_height="150dp"
android:layout_margin="10dp"/>
<ImageView
android:id="#+id/ivRectRounded"
android:layout_width="200dp"
android:layout_height="160dp"
android:layout_margin="10dp"/>
</LinearLayout>