Android-----自定义圆形的头像控件

亦凉 2022-08-09 09:59 273阅读 0赞

在现在的网络上圆形头像是非常常见的，圆形头像大多数使用在显示个人信息中的头像信息，今天就试试实现一个圆形的头像。

自定义一个CircleImageView，并且继承ImageView，用于显示圆形的图片。

package com.gjg.circleimageviewdemo;
    
    import android.content.Context;
    import android.content.res.TypedArray;
    import android.graphics.Bitmap;
    import android.graphics.BitmapShader;
    import android.graphics.Canvas;
    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.util.AttributeSet;
    import android.widget.ImageView;
    
    public class CircleImageView extends ImageView{
    
    	//设置scaletype为ScaleType.CENTER_CROP（均衡缩放）
    	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 = 1;
    
        private final RectF mDrawableRect = new RectF();
        private final RectF mBorderRect = new RectF();
    
        private final Matrix mShaderMatrix = new Matrix();
        
        private final Paint mBitmapPaint = new Paint();//画整个圆形的画笔
        private final Paint mBorderPaint = new Paint();//画边框的画笔
    
        private int mBorderColor;//圆边框的颜色
        private int mBorderWidth;//圆边框的宽度
    
        private Bitmap mBitmap;
        private BitmapShader mBitmapShader;
        private int mBitmapWidth;
        private int mBitmapHeight;
    
        private float mDrawableRadius;
        private float mBorderRadius;
    
        private boolean mReady;
        private boolean mSetupPending;
        
        
       
        public CircleImageView(Context context) {
            super(context);
            init();
        }
    
        public CircleImageView(Context context, AttributeSet attrs) {
            this(context, attrs, 0);
            init();
        }
    
        public CircleImageView(Context context, AttributeSet attrs, int defStyle) {
            super(context, attrs, defStyle);
    
            //从attrs.xml中获取自定义的属性
            TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.CircleImageView, defStyle, 0);
    
            mBorderWidth = a.getDimensionPixelSize(R.styleable.CircleImageView_border_width, 0);
            mBorderColor = a.getColor(R.styleable.CircleImageView_border_color, 0);
            //回收属性，避免对下次的使用造成影响
            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
        protected void onDraw(Canvas canvas) {
            if (getDrawable() == null) {
                return;
            }
            //画圆（圆形头像部分）
            canvas.drawCircle(getWidth() / 2, getHeight() / 2, mDrawableRadius, mBitmapPaint);
            //若设置了圆的边框宽度，将边框画出来
            if (mBorderWidth != 0) {
                canvas.drawCircle(getWidth() / 2, getHeight() / 2, 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 void setBorderColor(int borderColor) {
            if (borderColor == mBorderColor) {
                return;
            }
    
            mBorderColor = borderColor;
            mBorderPaint.setColor(mBorderColor);
            invalidate();
        }
    
        public int getBorderWidth() {
            return mBorderWidth;
        }
    
        public void setBorderWidth(int borderWidth) {
            if (borderWidth == mBorderWidth) {
                return;
            }
    
            mBorderWidth = borderWidth;
            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(int resId) {
            super.setImageResource(resId);
            mBitmap = getBitmapFromDrawable(getDrawable());
            setup();
        }
    
        @Override
        public void setImageURI(Uri uri) {
            super.setImageURI(uri);
            mBitmap = getBitmapFromDrawable(getDrawable());
            setup();
        }
    
        /**
         * 获取最后的圆形图片
         * @param drawable
         * @return Bitmap
         */
        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 (OutOfMemoryError e) {
                return null;
            }
        }
    
        private void setup() {
            if (!mReady) {
                mSetupPending = true;
                return;
            }
    
            if (mBitmap == null) {
                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);
    
            mBitmapHeight = mBitmap.getHeight();
            mBitmapWidth = mBitmap.getWidth();
    
            mBorderRect.set(0, 0, getWidth(), getHeight());
            mBorderRadius = Math.min((mBorderRect.height() - mBorderWidth) / 2, (mBorderRect.width() - mBorderWidth) / 2);
    
            mDrawableRect.set(mBorderWidth, mBorderWidth, mBorderRect.width() - mBorderWidth, mBorderRect.height() - mBorderWidth);
            mDrawableRadius = Math.min(mDrawableRect.height() / 2, mDrawableRect.width() / 2);
    
            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) + mBorderWidth, (int) (dy + 0.5f) + mBorderWidth);
    
            mBitmapShader.setLocalMatrix(mShaderMatrix);
        }
    	
    
    }

上面的 代码需要注意的是：

public CircleImageView(Context context, AttributeSet attrs, int defStyle) {
            super(context, attrs, defStyle);
    
            //从attrs.xml中获取自定义的属性
            TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.CircleImageView, defStyle, 0);
    
            mBorderWidth = a.getDimensionPixelSize(R.styleable.CircleImageView_border_width, 0);
            mBorderColor = a.getColor(R.styleable.CircleImageView_border_color, 0);
            //回收属性，避免对下次的使用造成影响
            a.recycle();
    
            init();
        }

从attrs.xml文件中获得自定义的属性后，需要调用recycle()方法。

布局文件：

注意上面的图片引用应该是： android:src="@drawable/headicon"  不要写成这种：android:background="@drawable/headicon"

后面的哪种仍然是矩形显示，不能圆形显示。

布局文件中的

xmlns:myapp="http://schemas.android.com/apk/res/com.gjg.circleimageviewdemo"

引用的自定义的属性，属性文件在values/attrs.xml

attrs.xml

<?xml version="1.0" encoding="utf-8"?>
    <resources>
    
        <declare-styleable name="CircleImageView">
            <attr name="border_width" format="dimension" />
            <attr name="border_color" format="color" />
        </declare-styleable>
        
    </resources>

引用的属性的用法：

myapp:border_color="#328843"
     myapp:border_width="2dp"

以myapp:开头，因为布局文件中的

xmlns:myapp="http://schemas.android.com/apk/res/com.gjg.circleimageviewdemo"

也是定义成myapp,后面跟的直接是attrs中定义的name。

在attrs.xml中，其中resource是根标签，可以在里面定义若干个declare-styleable，<declare-styleable name="CircleImageView">中name定义了变量的名称，下面可以再自定义多个属性，针对<attr name="border\_width" format="dimension" />来说，其属性的名称为"border\_width"，format指定了该属性类型为dimension，只能表示字体的大小。

format还可以指定其他的类型比如;

reference   表示引用，参考某一资源ID

string   表示字符串

color   表示颜色值

dimension   表示尺寸值

boolean   表示布尔值

integer   表示整型值

float   表示浮点值

fraction   表示百分数

enum   表示枚举值

flag   表示位运算  
  
效果如下：  
  
![Center][]

另外从网上搜了下，还可以用以下的方式直接将图裁剪成圆形图片，然后再显示。

/**
    	 * 直接将bitmap裁剪成圆形
    	 * @param v
    	 */
    	public void cropBitmap(View v){
    		Bitmap src=BitmapFactory.decodeResource(getResources(), R.drawable.headicon);
    		Bitmap bitmap=Bitmap.createBitmap(src);
    		Bitmap newbitmap=toRoundBitmap(bitmap);
    		ivHead.setImageBitmap(newbitmap);
    	}

/**
    	 * 转换图片成圆形
    	 * 
    	 * @param bitmap 传入Bitmap对象
    	 * @return
    	 */
    	public Bitmap toRoundBitmap(Bitmap bitmap) {
    		int width = bitmap.getWidth();
    		int height = bitmap.getHeight();
    		float roundPx;
    		float left, top, right, bottom, dst_left, dst_top, dst_right, dst_bottom;
    		if (width <= height) {
    			roundPx = width / 2;
    			top = 0;
    			bottom = width;
    			left = 0;
    			right = width;
    			height = width;
    			dst_left = 0;
    			dst_top = 0;
    			dst_right = width;
    			dst_bottom = width;
    		} else {
    			roundPx = height / 2;
    			float clip = (width - height) / 2;
    			left = clip;
    			right = width - clip;
    			top = 0;
    			bottom = height;
    			width = height;
    			dst_left = 0;
    			dst_top = 0;
    			dst_right = height;
    			dst_bottom = height;
    		}
    		Bitmap output = Bitmap.createBitmap(width, height, Config.ARGB_8888);
    		Canvas canvas = new Canvas(output);
    		final int color = 0xff424242;
    		final Paint paint = new Paint();
    		final Rect src = new Rect((int) left, (int) top, (int) right,
    				(int) bottom);
    		final Rect dst = new Rect((int) dst_left, (int) dst_top,
    				(int) dst_right, (int) dst_bottom);
    		final RectF rectF = new RectF(dst);
    		paint.setAntiAlias(true);
    		canvas.drawARGB(0, 0, 0, 0);
    		paint.setColor(color);
    		canvas.drawRoundRect(rectF, roundPx, roundPx, paint);
    		paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN));
    		canvas.drawBitmap(bitmap, src, dst, paint);
    		return output;
    	}

点击“直接裁剪”按钮，效果如下：

![Center 1][]

demo下载地址：[http://download.csdn.net/detail/dangnianmingyue\_gg/9203149][http_download.csdn.net_detail_dangnianmingyue_gg_9203149]

[Center]: /images/20220731/da3389abf3914a98b506b4cb9fb2ed53.png
[Center 1]: /images/20220731/186256b0b6d4492cb9c1616451da75b8.png
[http_download.csdn.net_detail_dangnianmingyue_gg_9203149]: http://download.csdn.net/detail/dangnianmingyue_gg/9203149