Android中设置图片的圆形遮罩的几种方式

编写不易，如有转载，请声明出处: 梦回河口：http://blog.csdn.net/zxc514257857/article/details/63834235

方式一 采用paint.setXfermode() 设置一个简单的圆形遮罩

  效果图如下：

  布局代码如下：

//（layout）activity_main.xml<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"                xmlns:tools="http://schemas.android.com/tools"                android:layout_width="match_parent"                android:layout_height="match_parent"                tools:context=".MainActivity" >    <ImageView        android:id="@+id/imageview"        android:src="@mipmap/pic"        android:layout_width="wrap_content"        android:layout_height="wrap_content"/></RelativeLayout>

  Activity代码如下：

//(activity)MainActivityimport android.graphics.Bitmap;import android.graphics.BitmapFactory;import android.graphics.Canvas;import android.graphics.Paint;import android.graphics.PorterDuff;import android.graphics.PorterDuffXfermode;import android.os.Bundle;import android.support.v7.app.AppCompatActivity;import android.widget.ImageView;public class MainActivity extends AppCompatActivity {    private ImageView mImageview;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        initView();        initData();    }    private void initView() {        mImageview = (ImageView) findViewById(R.id.imageview);    }    private void initData() {        //原图        Bitmap before = BitmapFactory.decodeResource(getResources(), R.mipmap.pic);        //遮罩图        Bitmap shade = BitmapFactory.decodeResource(getResources(), R.mipmap.circle);        //遮罩后图        Bitmap after = Bitmap.createBitmap(shade.getWidth(), shade.getHeight(), Bitmap.Config.ARGB_8888);        Canvas canvas = new Canvas(after);        Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG);        //关键代码        paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.DST_IN));        canvas.drawBitmap(before, 0, 0, null);        canvas.drawBitmap(shade, 0, 0, paint);        paint.setXfermode(null);        mImageview.setImageBitmap(after);        mImageview.setScaleType(ImageView.ScaleType.CENTER);    }}

  注：如果要改变圆形图片的大小，需要修改遮罩图的分辨率大小，原图大小也要相应改变

  Demo下载请移步：http://download.csdn.net/detail/zxc514257857/9833165

方式二 如果是从网络上加载出来的图片，可以使用图片加载框架中封装的方法轻松实现圆形遮罩效果

//例如Glide:Context context = MainActivity.this;String url = (String)list.get(1);ImageView pic = (ImageView)findViewById(R.id.pic);Glide.with(context).load(url).asBitmap().diskCacheStrategy(DiskCacheStrategy.ALL).centerCrop().into(new BitmapImageViewTarget(pic) {    @Override    protected void setResource(Bitmap resource) {        RoundedBitmapDrawable circularBitmapDrawable =                RoundedBitmapDrawableFactory.create(getResources(), resource);        circularBitmapDrawable.setCircular(true);        pic.setImageDrawable(circularBitmapDrawable);    }});

方式三 鸿神的两种实现方法

  自定义View实现：
http://blog.csdn.net/lmj623565791/article/details/24555655
  使用BitmapShader实现：
http://blog.csdn.net/lmj623565791/article/details/41967509

方式四 使用自定义的ImageView

  效果图如下：

  自定义ImageView代码如下：

//CustomRoundViewimport android.content.Context;import android.content.res.TypedArray;import android.graphics.Bitmap;import android.graphics.Canvas;import android.graphics.Paint;import android.graphics.PorterDuff;import android.graphics.PorterDuffXfermode;import android.graphics.Rect;import android.graphics.drawable.BitmapDrawable;import android.graphics.drawable.Drawable;import android.graphics.drawable.NinePatchDrawable;import android.util.AttributeSet;import android.widget.ImageView;public class CustomRoundView extends ImageView{    private int mBorderThickness = 0;    private Context mContext;    private int defaultColor = 0xFFFFFFFF;    // 如果只有其中一个有值，则只画一个圆形边框    private int mBorderOutsideColor = 0;    private int mBorderInsideColor = 0;    // 控件默认长、宽    private int defaultWidth = 0;    private int defaultHeight = 0;    public CustomRoundView(Context context) {        super(context);        mContext = context;    }    public CustomRoundView(Context context, AttributeSet attrs) {        super(context, attrs);        mContext = context;        setCustomAttributes(attrs);    }    public CustomRoundView(Context context, AttributeSet attrs, int defStyle) {        super(context, attrs, defStyle);        mContext = context;        setCustomAttributes(attrs);    }    private void setCustomAttributes(AttributeSet attrs) {        TypedArray a = mContext.obtainStyledAttributes(attrs,                R.styleable.roundview);        mBorderThickness = a.getDimensionPixelSize(                R.styleable.roundview_border_thickness, 0);        mBorderOutsideColor = a                .getColor(R.styleable.roundview_border_outside_color,                        defaultColor);        mBorderInsideColor = a.getColor(                R.styleable.roundview_border_inside_color, defaultColor);    }    @Override    protected void onDraw(Canvas canvas) {        Drawable drawable = getDrawable();        if (drawable == null) {            return;        }        if (getWidth() == 0 || getHeight() == 0) {            return;        }        this.measure(0, 0);        if (drawable.getClass() == NinePatchDrawable.class)            return;        Bitmap b = ((BitmapDrawable) drawable).getBitmap();        Bitmap bitmap = b.copy(Bitmap.Config.ARGB_8888, true);        if (defaultWidth == 0) {            defaultWidth = getWidth();        }        if (defaultHeight == 0) {            defaultHeight = getHeight();        }        int radius = 0;        if (mBorderInsideColor != defaultColor                && mBorderOutsideColor != defaultColor) {            // 定义画两个边框，分别为外圆边框和内圆边框            radius = (defaultWidth < defaultHeight ? defaultWidth                    : defaultHeight) / 2 - 2 * mBorderThickness;            // 画内圆            drawCircleBorder(canvas, radius + mBorderThickness / 2,                    mBorderInsideColor);            // 画外圆            drawCircleBorder(canvas, radius + mBorderThickness                    + mBorderThickness / 2, mBorderOutsideColor);        } else if (mBorderInsideColor != defaultColor                && mBorderOutsideColor == defaultColor) {            // 定义画一个边框            radius = (defaultWidth < defaultHeight ? defaultWidth                    : defaultHeight) / 2 - mBorderThickness;            drawCircleBorder(canvas, radius + mBorderThickness / 2,                    mBorderInsideColor);        } else if (mBorderInsideColor == defaultColor                && mBorderOutsideColor != defaultColor) {            // 定义画一个边框            radius = (defaultWidth < defaultHeight ? defaultWidth                    : defaultHeight) / 2 - mBorderThickness;            drawCircleBorder(canvas, radius + mBorderThickness / 2,                    mBorderOutsideColor);        } else {            // 没有边框            radius = (defaultWidth < defaultHeight ? defaultWidth                    : defaultHeight) / 2;        }        Bitmap roundBitmap = getCroppedRoundBitmap(bitmap, radius);        canvas.drawBitmap(roundBitmap, defaultWidth / 2 - radius, defaultHeight                / 2 - radius, null);    }    // 获取裁剪后的圆形图片    public Bitmap getCroppedRoundBitmap(Bitmap bmp, int radius) {        Bitmap scaledSrcBmp;        int diameter = radius * 2;        // 为了防止宽高不相等，造成圆形图片变形，因此截取长方形中处于中间位置最大的正方形图片        int bmpWidth = bmp.getWidth();        int bmpHeight = bmp.getHeight();        int squareWidth = 0, squareHeight = 0;        int x = 0, y = 0;        Bitmap squareBitmap;        if (bmpHeight > bmpWidth) {            // 高大于宽            squareWidth = squareHeight = bmpWidth;            x = 0;            y = (bmpHeight - bmpWidth) / 2;            // 截取正方形图片            squareBitmap = Bitmap.createBitmap(bmp, x, y, squareWidth,                    squareHeight);        } else if (bmpHeight < bmpWidth) {            // 宽大于高            squareWidth = squareHeight = bmpHeight;            x = (bmpWidth - bmpHeight) / 2;            y = 0;            squareBitmap = Bitmap.createBitmap(bmp, x, y, squareWidth,                    squareHeight);        } else {            squareBitmap = bmp;        }        if (squareBitmap.getWidth() != diameter                || squareBitmap.getHeight() != diameter) {            scaledSrcBmp = Bitmap.createScaledBitmap(squareBitmap, diameter,                    diameter, true);        } else {            scaledSrcBmp = squareBitmap;        }        Bitmap output = Bitmap.createBitmap(scaledSrcBmp.getWidth(),                scaledSrcBmp.getHeight(), Bitmap.Config.ARGB_8888);        Canvas canvas = new Canvas(output);        Paint paint = new Paint();        Rect rect = new Rect(0, 0, scaledSrcBmp.getWidth(),                scaledSrcBmp.getHeight());        paint.setAntiAlias(true);        paint.setFilterBitmap(true);        paint.setDither(true);        canvas.drawARGB(0, 0, 0, 0);        canvas.drawCircle(scaledSrcBmp.getWidth() / 2,                scaledSrcBmp.getHeight() / 2, scaledSrcBmp.getWidth() / 2,                paint);        paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_IN));        canvas.drawBitmap(scaledSrcBmp, rect, rect, paint);        bmp = null;        squareBitmap = null;        scaledSrcBmp = null;        return output;    }    //边缘画圆    private void drawCircleBorder(Canvas canvas, int radius, int color) {        Paint paint = new Paint();        //去锯齿        paint.setAntiAlias(true);        paint.setFilterBitmap(true);        paint.setDither(true);        paint.setColor(color);        //设置paint的　style　为STROKE：空心        paint.setStyle(Paint.Style.STROKE);        //设置paint的外框宽度        paint.setStrokeWidth(mBorderThickness);        canvas.drawCircle(defaultWidth / 2, defaultHeight / 2, radius, paint);    }}

  布局代码如下：

//（layout）activity_main.xml<?xml version="1.0" encoding="utf-8"?><RelativeLayout    xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:id="@+id/activity_main"    android:layout_width="match_parent"    android:layout_height="match_parent"    tools:context=".MainActivity">    <com.test.customroundview.CustomRoundView        android:src="@mipmap/pic"        android:id="@+id/roundview"        android:layout_width="200dp"        android:layout_height="200dp"/></RelativeLayout>-----------------------------------------------------------//（values）attrs.xml<?xml version="1.0" encoding="utf-8"?><resources>    <declare-styleable name="roundview">        <attr name="border_thickness" format="dimension" />        <attr name="border_inside_color" format="color" />        <attr name="border_outside_color" format="color"/>    </declare-styleable></resources>-----------------------------------------------------------

  Activity代码如下：

//MainActivityimport android.support.v7.app.AppCompatActivity;import android.os.Bundle;public class MainActivity extends AppCompatActivity {    //截取长方形中处于中间位置最大的正方形图片,只要头像处于图片中间不要太偏就可以很好的截出效果    private CustomRoundView mRoundView;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        initView();        initData();    }    private void initView(){        mRoundView = (CustomRoundView) findViewById(R.id.roundview);    }    private void initData(){        mRoundView.setImageResource(R.mipmap.pic);    }}

注：如果要改变圆形图片的大小，修改：

<com.test.customroundview.CustomRoundView        android:src="@mipmap/pic"        android:id="@+id/roundview"        android:layout_width="XXXdp"        android:layout_height="XXXdp"/>

  Demo下载请移步：http://download.csdn.net/detail/zxc514257857/9833264

方式五 CircleImageView (也是自定义View 经常和Glide搭配使用)

  效果图如下：

  自定义ImageView代码如下：

//(view)CircleImageViewimport android.content.Context;import android.content.res.TypedArray;import android.graphics.Bitmap;import android.graphics.BitmapShader;import android.graphics.Canvas;import android.graphics.Color;import android.graphics.ColorFilter;import android.graphics.Matrix;import android.graphics.Paint;import android.graphics.RectF;import android.graphics.Shader;import android.graphics.drawable.BitmapDrawable;import android.graphics.drawable.ColorDrawable;import android.graphics.drawable.Drawable;import android.net.Uri;import android.support.annotation.DrawableRes;import android.util.AttributeSet;import android.widget.ImageView;import com.test.circleimageview.R;public class CircleImageView extends ImageView {    private static final ScaleType SCALE_TYPE = ScaleType.CENTER_CROP;    private static final Bitmap.Config BITMAP_CONFIG = Bitmap.Config.ARGB_8888;    private static final int COLORDRAWABLE_DIMENSION = 2;    private static final int DEFAULT_BORDER_WIDTH = 0;    private static final int DEFAULT_BORDER_COLOR = Color.BLACK;    private static final int DEFAULT_FILL_COLOR = Color.TRANSPARENT;    private static final boolean DEFAULT_BORDER_OVERLAY = false;    private final RectF mDrawableRect = new RectF();    private final RectF mBorderRect = new RectF();    private final Matrix mShaderMatrix = new Matrix();    private final Paint mBitmapPaint = new Paint();    private final Paint mBorderPaint = new Paint();    private final Paint mFillPaint = new Paint();    private int mBorderColor = DEFAULT_BORDER_COLOR;    private int mBorderWidth = DEFAULT_BORDER_WIDTH;    private int mFillColor = DEFAULT_FILL_COLOR;    private Bitmap mBitmap;    private BitmapShader mBitmapShader;    private int mBitmapWidth;    private int mBitmapHeight;    private float mDrawableRadius;    private float mBorderRadius;    private ColorFilter mColorFilter;    private boolean mReady;    private boolean mSetupPending;    private boolean mBorderOverlay;    public CircleImageView(Context context) {        super(context);        init();    }    public CircleImageView(Context context, AttributeSet attrs) {        this(context, attrs, 0);    }    public CircleImageView(Context context, AttributeSet attrs, int defStyle) {        super(context, attrs, defStyle);        TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.CircleImageView, defStyle, 0);        mBorderWidth = a.getDimensionPixelSize(R.styleable.CircleImageView_civ_border_width, DEFAULT_BORDER_WIDTH);        mBorderColor = a.getColor(R.styleable.CircleImageView_civ_border_color, DEFAULT_BORDER_COLOR);        mBorderOverlay = a.getBoolean(R.styleable.CircleImageView_civ_border_overlay, DEFAULT_BORDER_OVERLAY);        mFillColor = a.getColor(R.styleable.CircleImageView_civ_fill_color, DEFAULT_FILL_COLOR);        a.recycle();        init();    }    private void init() {        super.setScaleType(SCALE_TYPE);        mReady = true;        if (mSetupPending) {            setup();            mSetupPending = false;        }    }    @Override    public ScaleType getScaleType() {        return SCALE_TYPE;    }    @Override    public void setScaleType(ScaleType scaleType) {        if (scaleType != SCALE_TYPE) {            throw new IllegalArgumentException(String.format("ScaleType %s not supported.", scaleType));        }    }    @Override    public void setAdjustViewBounds(boolean adjustViewBounds) {        if (adjustViewBounds) {            throw new IllegalArgumentException("adjustViewBounds not supported.");        }    }    @Override    protected void onDraw(Canvas canvas) {        if (mBitmap == null) {            return;        }        if (mFillColor != Color.TRANSPARENT) {            canvas.drawCircle(getWidth() / 2.0f, getHeight() / 2.0f, mDrawableRadius, mFillPaint);        }        canvas.drawCircle(getWidth() / 2.0f, getHeight() / 2.0f, mDrawableRadius, mBitmapPaint);        if (mBorderWidth != 0) {            canvas.drawCircle(getWidth() / 2.0f, getHeight() / 2.0f, mBorderRadius, mBorderPaint);        }    }    @Override    protected void onSizeChanged(int w, int h, int oldw, int oldh) {        super.onSizeChanged(w, h, oldw, oldh);        setup();    }    public int getBorderColor() {        return mBorderColor;    }    public int getFillColor() {        return mFillColor;    }    public int getBorderWidth() {        return mBorderWidth;    }    public void setBorderWidth(int borderWidth) {        if (borderWidth == mBorderWidth) {            return;        }        mBorderWidth = borderWidth;        setup();    }    public boolean isBorderOverlay() {        return mBorderOverlay;    }    public void setBorderOverlay(boolean borderOverlay) {        if (borderOverlay == mBorderOverlay) {            return;        }        mBorderOverlay = borderOverlay;        setup();    }    @Override    public void setImageBitmap(Bitmap bm) {        super.setImageBitmap(bm);        mBitmap = bm;        setup();    }    @Override    public void setImageDrawable(Drawable drawable) {        super.setImageDrawable(drawable);        mBitmap = getBitmapFromDrawable(drawable);        setup();    }    @Override    public void setImageResource(@DrawableRes int resId) {        super.setImageResource(resId);        mBitmap = getBitmapFromDrawable(getDrawable());        setup();    }    @Override    public void setImageURI(Uri uri) {        super.setImageURI(uri);        mBitmap = uri != null ? getBitmapFromDrawable(getDrawable()) : null;        setup();    }    @Override    public void setColorFilter(ColorFilter cf) {        if (cf == mColorFilter) {            return;        }        mColorFilter = cf;        mBitmapPaint.setColorFilter(mColorFilter);        invalidate();    }    private Bitmap getBitmapFromDrawable(Drawable drawable) {        if (drawable == null) {            return null;        }        if (drawable instanceof BitmapDrawable) {            return ((BitmapDrawable) drawable).getBitmap();        }        try {            Bitmap bitmap;            if (drawable instanceof ColorDrawable) {                bitmap = Bitmap.createBitmap(COLORDRAWABLE_DIMENSION, COLORDRAWABLE_DIMENSION, BITMAP_CONFIG);            } else {                bitmap = Bitmap.createBitmap(drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight(), BITMAP_CONFIG);            }            Canvas canvas = new Canvas(bitmap);            drawable.setBounds(0, 0, canvas.getWidth(), canvas.getHeight());            drawable.draw(canvas);            return bitmap;        } catch (Exception e) {            e.printStackTrace();            return null;        }    }    private void setup() {        if (!mReady) {            mSetupPending = true;            return;        }        if (getWidth() == 0 && getHeight() == 0) {            return;        }        if (mBitmap == null) {            invalidate();            return;        }        mBitmapShader = new BitmapShader(mBitmap, Shader.TileMode.CLAMP, Shader.TileMode.CLAMP);        mBitmapPaint.setAntiAlias(true);        mBitmapPaint.setShader(mBitmapShader);        mBorderPaint.setStyle(Paint.Style.STROKE);        mBorderPaint.setAntiAlias(true);        mBorderPaint.setColor(mBorderColor);        mBorderPaint.setStrokeWidth(mBorderWidth);        mFillPaint.setStyle(Paint.Style.FILL);        mFillPaint.setAntiAlias(true);        mFillPaint.setColor(mFillColor);        mBitmapHeight = mBitmap.getHeight();        mBitmapWidth = mBitmap.getWidth();        mBorderRect.set(0, 0, getWidth(), getHeight());        mBorderRadius = Math.min((mBorderRect.height() - mBorderWidth) / 2.0f, (mBorderRect.width() - mBorderWidth) / 2.0f);        mDrawableRect.set(mBorderRect);        if (!mBorderOverlay) {            mDrawableRect.inset(mBorderWidth, mBorderWidth);        }        mDrawableRadius = Math.min(mDrawableRect.height() / 2.0f, mDrawableRect.width() / 2.0f);        updateShaderMatrix();        invalidate();    }    private void updateShaderMatrix() {        float scale;        float dx = 0;        float dy = 0;        mShaderMatrix.set(null);        if (mBitmapWidth * mDrawableRect.height() > mDrawableRect.width() * mBitmapHeight) {            scale = mDrawableRect.height() / (float) mBitmapHeight;            dx = (mDrawableRect.width() - mBitmapWidth * scale) * 0.5f;        } else {            scale = mDrawableRect.width() / (float) mBitmapWidth;            dy = (mDrawableRect.height() - mBitmapHeight * scale) * 0.5f;        }        mShaderMatrix.setScale(scale, scale);        mShaderMatrix.postTranslate((int) (dx + 0.5f) + mDrawableRect.left, (int) (dy + 0.5f) + mDrawableRect.top);        mBitmapShader.setLocalMatrix(mShaderMatrix);    }}

  布局代码如下：

//(layout)activity_main.xml<?xml version="1.0" encoding="utf-8"?><RelativeLayout    xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:id="@+id/activity_main"    android:layout_width="match_parent"    android:layout_height="match_parent"    tools:context=".activity.MainActivity">    <com.test.circleimageview.view.CircleImageView        android:id="@+id/imageView"        android:layout_width="200dp"        android:layout_height="200dp"/></RelativeLayout>-----------------------------------------------------------//(values)attrs.xml<resources>    <declare-styleable name="CircleImageView">        <attr name="civ_border_width" format="dimension" />        <attr name="civ_border_color" format="color" />        <attr name="civ_border_overlay" format="boolean" />        <attr name="civ_fill_color" format="color" />    </declare-styleable></resources>

  Activity代码如下：

//(activity)MainActivityimport android.os.Bundle;import android.support.v7.app.AppCompatActivity;import com.test.circleimageview.R;import com.test.circleimageview.view.CircleImageView;public class MainActivity extends AppCompatActivity {    private CircleImageView mImageView;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        initView();        initData();    }    private void initView() {        mImageView = (CircleImageView) findViewById(R.id.imageView);    }    private void initData(){        mImageView.setImageResource(R.mipmap.pic);    }}

  注：如果要改变圆形图片的大小，修改：

<com.test.circleimageview.view.CircleImageView        android:id="@+id/imageView"        android:layout_width="XXXdp"        android:layout_height="XXXdp"/>

Demo下载请移步：http://download.csdn.net/detail/zxc514257857/9833756


———-因本人才疏学浅，如博客或Demo中有错误的地方请大家随意指出，与大家一起讨论，共同进步，谢谢！———-