Android应用自定义圆角图片RoundImageView
发布时间:2020-12-14 23:50:05 所属栏目:Java 来源:网络整理
导读:今天PHP站长网 52php.cn把收集自互联网的代码分享给大家,仅供参考。 Android开发中图片控件ImageView默认的样子是矩形,方方正正的。在我们实际的项目中,有时候这些方正的图片显得有些呆板,我们就需要其它样式的图片,
以下代码由PHP站长网 52php.cn收集自互联网 现在PHP站长网小编把它分享给大家,仅供参考
Android开发中图片控件ImageView默认的样子是矩形,方方正正的。在我们实际的项目中,有时候这些方正的图片显得有些呆板,我们就需要其它样式的图片,比较圆形图片(The rounded picture), 常见的就是app中用户头像等。要得到圆形图片有很多方式,比如draw一个circle,也可以用切好的圆形图片做背景或者写一个xml实现圆角功能等 等。不过在项目中,如果我们有多个地方要把图片展示出圆形的,而且图片是从网络上取的,这种情况还一个个处理就麻烦了,我们可以定义个圆形图片组件 RoundImageView,然后在要用的地方把RoundImageView 当成ImageView一样使用就行了。我在最近做的项目中也用到了圆形图片,所以做个笔记,方便下次使用!
public class RoundImageView 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 RoundImageView(Context context) { super(context); mContext = context; } public RoundImageView(Context context,AttributeSet attrs) { super(context,attrs); mContext = context; setCustomAttributes(attrs); } public RoundImageView(Context context,AttributeSet attrs,int defStyle) { super(context,attrs,defStyle); mContext = context; setCustomAttributes(attrs); } private void setCustomAttributes(AttributeSet attrs) {//这里要用到自定义属性 TypedArray a = mContext.obtainStyledAttributes(attrs,R.styleable.RoundImageView); mBorderThickness = a.getDimensionPixelSize( R.styleable.RoundImageView_border_thickness,0); mBorderOutsideColor = a .getColor(R.styleable.RoundImageView_border_outside_color,defaultColor); mBorderInsideColor = a.getColor( R.styleable.RoundImageView_border_inside_color,defaultColor); } @Override protected void onDraw(Canvas canvas) { Drawable drawable = getDrawable(); if (drawable == null) { return; } if (getWidth() == 0 || getHeight() == 0) { return; } 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,mBorderInsideColor); } else if (mBorderInsideColor == defaultColor && mBorderOutsideColor != defaultColor) {// 定义画一个边框 radius = (defaultWidth < defaultHeight ? defaultWidth : defaultHeight) / 2 - mBorderThickness; drawCircleBorder(canvas,mBorderOutsideColor); } else {// 没有边框 radius = (defaultWidth < defaultHeight ? defaultWidth : defaultHeight) / 2; } Bitmap roundBitmap = getCroppedRoundBitmap(bitmap,radius); bitmap = null; 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,squareHeight); } else { squareBitmap = bmp; } if (squareBitmap.getWidth() != diameter || squareBitmap.getHeight() != diameter) { scaledSrcBmp = Bitmap.createScaledBitmap(squareBitmap,diameter,true); } else { scaledSrcBmp = squareBitmap; } Bitmap output = Bitmap.createBitmap(scaledSrcBmp.getWidth(),scaledSrcBmp.getHeight(),Config.ARGB_8888); Canvas canvas = new Canvas(output); Paint paint = new Paint(); Rect rect = new Rect(0,scaledSrcBmp.getWidth(),scaledSrcBmp.getHeight()); paint.setAntiAlias(true); paint.setFilterBitmap(true); paint.setDither(true); canvas.drawARGB(0,0); canvas.drawCircle(scaledSrcBmp.getWidth() / 2,scaledSrcBmp.getHeight() / 2,scaledSrcBmp.getWidth() / 2,paint); paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN)); canvas.drawBitmap(scaledSrcBmp,rect,paint); // bitmap回收(recycle导致在布局文件XML看不到效果) // bmp.recycle(); // squareBitmap.recycle(); // scaledSrcBmp.recycle(); 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); } } <?xml version="1.0" encoding="utf-8"?> <resources> <declare-styleable name="RoundImageView"> <attr name="border_thickness" format="dimension" /> <attr name="border_outside_color" format="color" /> <attr name="border_inside_color" format="color" /> </declare-styleable> </resources> 以上内容由PHP站长网【52php.cn】收集整理供大家参考研究 如果以上内容对您有帮助,欢迎收藏、点赞、推荐、分享。 (编辑:李大同) 【声明】本站内容均来自网络,其相关言论仅代表作者个人观点,不代表本站立场。若无意侵犯到您的权利,请及时与联系站长删除相关内容! |