How to give hexagon shape to ImageView

How to give hexagon shape to ImageView . Is it possible to do in same way ? If so then how. If this is not possible through this then how this could be achieved ?

<shape xmlns:android="http//schemas.android.com/apk/res/android"
       android:shape="hexagon">
  <solid android:color="#ffffffff" />
  <size android:width="60dp"
        android:height="40dp" />
</shape>

Screenshot

enter image description here

Here I can't do masking image because I can not detect which portion of bitmap I should crop to get hexagon shape bitmap. So I am looking for the answer to give hexagon shape to ImageView


Solution 1:

Try this View. You might want to adjust it for your specific needs, but it draws a hexagon mask with a border on top of a view. The background resource goes below the mask.

The result:

enter image description here

The code:

HexagonMaskView.java

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Path;
import android.graphics.Region;
import android.util.AttributeSet;
import android.view.View;

public class HexagonMaskView extends View {
    private Path hexagonPath;
    private Path hexagonBorderPath;
    private float radius;
    private float width, height;
    private int maskColor;

public HexagonMaskView(Context context) {
    super(context);
    init();
}

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

public HexagonMaskView(Context context, AttributeSet attrs, int defStyleAttr) {
    super(context, attrs, defStyleAttr);
    init();
}

private void init() {
    hexagonPath = new Path();
    hexagonBorderPath = new Path();
    maskColor = 0xFF01FF77;
}

public void setRadius(float r) {
    this.radius = r;
    calculatePath();
}

public void setMaskColor(int color) {
    this.maskColor = color;
    invalidate();
}

private void calculatePath() {
    float triangleHeight = (float) (Math.sqrt(3) * radius / 2);
    float centerX = width/2;
    float centerY = height/2;
    hexagonPath.moveTo(centerX, centerY + radius);
    hexagonPath.lineTo(centerX - triangleHeight, centerY + radius/2);
    hexagonPath.lineTo(centerX - triangleHeight, centerY - radius/2);
    hexagonPath.lineTo(centerX, centerY - radius);
    hexagonPath.lineTo(centerX + triangleHeight, centerY - radius/2);
    hexagonPath.lineTo(centerX + triangleHeight, centerY + radius/2);
    hexagonPath.moveTo(centerX, centerY + radius);

    float radiusBorder = radius - 5;    
    float triangleBorderHeight = (float) (Math.sqrt(3) * radiusBorder / 2);
    hexagonBorderPath.moveTo(centerX, centerY + radiusBorder);
    hexagonBorderPath.lineTo(centerX - triangleBorderHeight, centerY + radiusBorder/2);
    hexagonBorderPath.lineTo(centerX - triangleBorderHeight, centerY - radiusBorder/2);
    hexagonBorderPath.lineTo(centerX, centerY - radiusBorder);
    hexagonBorderPath.lineTo(centerX + triangleBorderHeight, centerY - radiusBorder/2);
    hexagonBorderPath.lineTo(centerX + triangleBorderHeight, centerY + radiusBorder/2);
    hexagonBorderPath.moveTo(centerX, centerY + radiusBorder);
    invalidate();
}

@Override
public void onDraw(Canvas c){
    super.onDraw(c);
    c.clipPath(hexagonBorderPath, Region.Op.DIFFERENCE);
    c.drawColor(Color.WHITE);
    c.save();
    c.clipPath(hexagonPath, Region.Op.DIFFERENCE);
    c.drawColor(maskColor);
    c.save();
}

// getting the view size and default radius
@Override
public void onMeasure(int widthMeasureSpec, int heightMeasureSpec){
    super.onMeasure(widthMeasureSpec, heightMeasureSpec);
    width = MeasureSpec.getSize(widthMeasureSpec);
    height =  MeasureSpec.getSize(heightMeasureSpec);
    radius = height / 2 - 10;
    calculatePath();
}
}

Update 29.07.2016

A better way to only clip the source image without painting the whole view's background. Switched to an ImageView as a base class to benefit from the scaleType. I also did some code refactoring.

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Path;
import android.graphics.PorterDuff;
import android.graphics.Region;
import android.util.AttributeSet;
import android.widget.ImageView;

public class HexagonMaskView extends ImageView {
    private Path hexagonPath;
    private Path hexagonBorderPath;
    private Paint mBorderPaint;

    public HexagonMaskView(Context context) {
        super(context);
        init();
    }

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

    public HexagonMaskView(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        init();
    }

    private void init() {
        this.hexagonPath = new Path();
        this.hexagonBorderPath = new Path();

        this.mBorderPaint = new Paint();
        this.mBorderPaint.setColor(Color.WHITE);
        this.mBorderPaint.setStrokeCap(Paint.Cap.ROUND);
        this.mBorderPaint.setStrokeWidth(50f);
        this.mBorderPaint.setStyle(Paint.Style.STROKE);
    }

    public void setRadius(float radius) {
        calculatePath(radius);
    }

    public void setBorderColor(int color) {
        this.mBorderPaint.setColor(color);
        invalidate();
    }

    private void calculatePath(float radius) {
        float halfRadius = radius / 2f;
        float triangleHeight = (float) (Math.sqrt(3.0) * halfRadius);
        float centerX = getMeasuredWidth() / 2f;
        float centerY = getMeasuredHeight() / 2f;

        this.hexagonPath.reset();
        this.hexagonPath.moveTo(centerX, centerY + radius);
        this.hexagonPath.lineTo(centerX - triangleHeight, centerY + halfRadius);
        this.hexagonPath.lineTo(centerX - triangleHeight, centerY - halfRadius);
        this.hexagonPath.lineTo(centerX, centerY - radius);
        this.hexagonPath.lineTo(centerX + triangleHeight, centerY - halfRadius);
        this.hexagonPath.lineTo(centerX + triangleHeight, centerY + halfRadius);
        this.hexagonPath.close();

        float radiusBorder = radius - 5f;
        float halfRadiusBorder = radiusBorder / 2f;
        float triangleBorderHeight = (float) (Math.sqrt(3.0) * halfRadiusBorder);

        this.hexagonBorderPath.reset();
        this.hexagonBorderPath.moveTo(centerX, centerY + radiusBorder);
        this.hexagonBorderPath.lineTo(centerX - triangleBorderHeight, centerY + halfRadiusBorder);
        this.hexagonBorderPath.lineTo(centerX - triangleBorderHeight, centerY - halfRadiusBorder);
        this.hexagonBorderPath.lineTo(centerX, centerY - radiusBorder);
        this.hexagonBorderPath.lineTo(centerX + triangleBorderHeight, centerY - halfRadiusBorder);
        this.hexagonBorderPath.lineTo(centerX + triangleBorderHeight, centerY + halfRadiusBorder);
        this.hexagonBorderPath.close();
        invalidate();
    }

    @Override
    public void onDraw(Canvas c) {
        c.drawPath(hexagonBorderPath, mBorderPaint);
        c.clipPath(hexagonPath, Region.Op.INTERSECT);
        c.drawColor(Color.TRANSPARENT, PorterDuff.Mode.CLEAR);
        super.onDraw(c);
    }

    @Override
    public void onMeasure(int widthMeasureSpec, int heightMeasureSpec){
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
        int width = MeasureSpec.getSize(widthMeasureSpec);
        int height = MeasureSpec.getSize(heightMeasureSpec);
        setMeasuredDimension(width, height);
        calculatePath(Math.min(width / 2f, height / 2f) - 10f);
    }
}

Example layout:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    android:background="@android:color/holo_green_dark">

    <com.scelus.hexagonmaskimproved.HexagonMaskView
        android:id="@+id/image"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:src="@drawable/bear"
        android:background="@android:color/holo_green_light"/>

</RelativeLayout>

New result

Solution 2:

Here is my working code for this, it supports shadows to:

import android.annotation.SuppressLint;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapShader;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Path;
import android.graphics.PorterDuff;
import android.graphics.Shader;
import android.graphics.drawable.BitmapDrawable;
import android.util.AttributeSet;
import android.widget.ImageView;

public class HexagonImageView extends ImageView {

    private Path hexagonPath;
    private Path hexagonBorderPath;
    private float radius;
    private Bitmap image;
    private int viewWidth;
    private int viewHeight;
    private Paint paint;
    private BitmapShader shader;
    private Paint paintBorder;
    private int borderWidth = 4;

    public HexagonImageView(Context context) {
        super(context);
        setup();
    }

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

    public HexagonImageView(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        setup();
    }

    private void setup() {
        paint = new Paint();
        paint.setAntiAlias(true);

        paintBorder = new Paint();
        setBorderColor(Color.WHITE);
        paintBorder.setAntiAlias(true);
        this.setLayerType(LAYER_TYPE_SOFTWARE, paintBorder);
        paintBorder.setShadowLayer(4.0f, 1.0f, 1.0f, Color.BLACK);

        hexagonPath = new Path();
        hexagonBorderPath = new Path();
    }

    public void setRadius(float r) {
        this.radius = r;
        calculatePath();
    }

    public void setBorderWidth(int borderWidth)  {
        this.borderWidth = borderWidth;
        this.invalidate();
    }

    public void setBorderColor(int borderColor)  {
        if (paintBorder != null)
            paintBorder.setColor(borderColor);

        this.invalidate();
    }

    private void calculatePath() {

        float triangleHeight = (float) (Math.sqrt(3) * radius / 2);
        float centerX = viewWidth/2;
        float centerY = viewHeight/2;

        hexagonBorderPath.moveTo(centerX, centerY + radius);
        hexagonBorderPath.lineTo(centerX - triangleHeight, centerY + radius/2);
        hexagonBorderPath.lineTo(centerX - triangleHeight, centerY - radius/2);
        hexagonBorderPath.lineTo(centerX, centerY - radius);
        hexagonBorderPath.lineTo(centerX + triangleHeight, centerY - radius/2);
        hexagonBorderPath.lineTo(centerX + triangleHeight, centerY + radius/2);
        hexagonBorderPath.moveTo(centerX, centerY + radius);

        float radiusBorder = radius - borderWidth;    
        float triangleBorderHeight = (float) (Math.sqrt(3) * radiusBorder / 2);

        hexagonPath.moveTo(centerX, centerY + radiusBorder);
        hexagonPath.lineTo(centerX - triangleBorderHeight, centerY + radiusBorder/2);
        hexagonPath.lineTo(centerX - triangleBorderHeight, centerY - radiusBorder/2);
        hexagonPath.lineTo(centerX, centerY - radiusBorder);
        hexagonPath.lineTo(centerX + triangleBorderHeight, centerY - radiusBorder/2);
        hexagonPath.lineTo(centerX + triangleBorderHeight, centerY + radiusBorder/2);
        hexagonPath.moveTo(centerX, centerY + radiusBorder);

        invalidate();
    }

    private void loadBitmap()  {
        BitmapDrawable bitmapDrawable = (BitmapDrawable) this.getDrawable();

        if (bitmapDrawable != null)
            image = bitmapDrawable.getBitmap();
    }

    @SuppressLint("DrawAllocation")
    @Override
    public void onDraw(Canvas canvas){
        super.onDraw(canvas);

        loadBitmap();

        // init shader
        if (image != null) {

            canvas.drawColor(Color.TRANSPARENT, PorterDuff.Mode.CLEAR);

            shader = new BitmapShader(Bitmap.createScaledBitmap(image, canvas.getWidth(), canvas.getHeight(), false), Shader.TileMode.CLAMP, Shader.TileMode.CLAMP);
            paint.setShader(shader);

            canvas.drawPath(hexagonBorderPath, paintBorder);
            canvas.drawPath(hexagonPath, paint);
        }

    }

    @Override
    public void onMeasure(int widthMeasureSpec, int heightMeasureSpec){
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);

        int width = measureWidth(widthMeasureSpec);
        int height = measureHeight(heightMeasureSpec, widthMeasureSpec);

        viewWidth = width - (borderWidth * 2);
        viewHeight = height - (borderWidth * 2);

        radius = height / 2 - borderWidth;

        calculatePath();

        setMeasuredDimension(width, height);
    }

    private int measureWidth(int measureSpec)   {
        int result = 0;
        int specMode = MeasureSpec.getMode(measureSpec);
        int specSize = MeasureSpec.getSize(measureSpec);

        if (specMode == MeasureSpec.EXACTLY)  {
            result = specSize;
        }
        else {
            result = viewWidth;
        }

        return result;
    }

    private int measureHeight(int measureSpecHeight, int measureSpecWidth)  {
        int result = 0;
        int specMode = MeasureSpec.getMode(measureSpecHeight);
        int specSize = MeasureSpec.getSize(measureSpecHeight);

        if (specMode == MeasureSpec.EXACTLY) {
            result = specSize;
        }
        else {
            result = viewHeight;
        }

        return (result + 2);
    }


}