先上效果图:
实现方法一:
- /**
- * 获取圆角位图的方法
- *
- * @param bitmap
- * 需要转化成圆角的位图
- * @param pixels
- * 圆角的度数,数值越大,圆角越大
- * @return 处理后的圆角位图
- */
- public static Bitmap toRoundCornerImage(Bitmap bitmap, int pixels) {
- Bitmap output = Bitmap.createBitmap(bitmap.getWidth(), bitmap.getHeight(), Config.ARGB_8888);
- Canvas canvas = new Canvas(output);
- final int color = 0xff424242;
- final Paint paint = new Paint();
- final Rect rect = new Rect(0, 0, bitmap.getWidth(), bitmap.getHeight());
- final RectF rectF = new RectF(rect);
- final float roundPx = pixels;
- // 抗锯齿
- 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, rect, rect, paint);
- return output;
- }
实现方法二:
- package com.loopfire.meitaotao.view.roundImageView;
- import com.loopfire.meitaotao.R;
- import android.content.Context;
- import android.content.res.TypedArray;
- import android.graphics.Bitmap;
- import android.graphics.Bitmap.Config;
- import android.graphics.Canvas;
- import android.graphics.Color;
- import android.graphics.Paint;
- import android.graphics.Path;
- import android.graphics.PorterDuff;
- import android.graphics.PorterDuffXfermode;
- import android.graphics.RectF;
- import android.util.AttributeSet;
- import android.widget.ImageView;
- /**
- * 实现圆角image
- *
- * @author Administrator
- *
- */
- public class RoundAngleImageView extends ImageView {
- private Paint paint;
- /**
- * 个人理解是
- *
- * 这两个都是画圆的半径
- */
- private int roundWidth = 20;
- private int roundHeight = 20;
- private Paint paint2;
- public RoundAngleImageView(Context context, AttributeSet attrs, int defStyle) {
- super(context, attrs, defStyle);
- init(context, attrs);
- }
- public RoundAngleImageView(Context context, AttributeSet attrs) {
- super(context, attrs);
- init(context, attrs);
- }
- public RoundAngleImageView(Context context) {
- super(context);
- init(context, null);
- }
- private void init(Context context, AttributeSet attrs) {
- if (attrs != null) {
- TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.RoundAngleImageView);
- roundWidth = a.getDimensionPixelSize(R.styleable.RoundAngleImageView_roundWidth, roundWidth);
- roundHeight = a.getDimensionPixelSize(R.styleable.RoundAngleImageView_roundHeight, roundHeight);
- } else {
- float density = context.getResources().getDisplayMetrics().density;
- roundWidth = (int) (roundWidth * density);
- roundHeight = (int) (roundHeight * density);
- }
- paint = new Paint();
- paint.setColor(Color.WHITE);
- paint.setAntiAlias(true);
- paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.DST_OUT));
- paint2 = new Paint();
- paint2.setXfermode(null);
- }
- @Override
- public void draw(Canvas canvas) {
- Bitmap bitmap = Bitmap.createBitmap(getWidth(), getHeight(), Config.ARGB_8888);
- Canvas canvas2 = new Canvas(bitmap);
- super.draw(canvas2);
- drawLiftUp(canvas2);
- drawLiftDown(canvas2);
- drawRightUp(canvas2);
- drawRightDown(canvas2);
- canvas.drawBitmap(bitmap, 0, 0, paint2);
- bitmap.recycle();
- }
- private void drawLiftUp(Canvas canvas) {
- Path path = new Path();
- path.moveTo(0, roundHeight);
- path.lineTo(0, 0);
- path.lineTo(roundWidth, 0);
- path.arcTo(new RectF(0, 0, roundWidth * 2, roundHeight * 2), -90, -90);
- path.close();
- canvas.drawPath(path, paint);
- }
- private void drawLiftDown(Canvas canvas) {
- Path path = new Path();
- path.moveTo(0, getHeight() - roundHeight);
- path.lineTo(0, getHeight());
- path.lineTo(roundWidth, getHeight());
- path.arcTo(new RectF(0, getHeight() - roundHeight * 2, roundWidth * 2, getHeight()), 90, 90);
- path.close();
- canvas.drawPath(path, paint);
- }
- private void drawRightDown(Canvas canvas) {
- Path path = new Path();
- path.moveTo(getWidth() - roundWidth, getHeight());
- path.lineTo(getWidth(), getHeight());
- path.lineTo(getWidth(), getHeight() - roundHeight);
- path.arcTo(new RectF(getWidth() - roundWidth * 2, getHeight() - roundHeight * 2, getWidth(), getHeight()), -0, 90);
- path.close();
- canvas.drawPath(path, paint);
- }
- private void drawRightUp(Canvas canvas) {
- Path path = new Path();
- path.moveTo(getWidth(), roundHeight);
- path.lineTo(getWidth(), 0);
- path.lineTo(getWidth() - roundWidth, 0);
- path.arcTo(new RectF(getWidth() - roundWidth * 2, 0, getWidth(), 0 + roundHeight * 2), -90, 90);
- path.close();
- canvas.drawPath(path, paint);
- }
- }
然后在values下建个xml文件attribute.xml
- <?xml version="1.0" encoding="utf-8"?>
- <resources>
- <declare-styleable name="RoundAngleImageView">
- <attr name="roundWidth" format="dimension" />
- <attr name="roundHeight" format="dimension" />
- </declare-styleable>
- </resources>
首先说明:两种方法都有一个相同点,重写了onDraw方法,方法里面都是采用重绘bitmap的方式实现圆角Image
第二种方法网上有很多相似例子,不过发现它们都有一个错误,就是左下角不能实现圆角,我的第二个方法就是
对网上的错误方法修改而成!