Android studio 实现圆形ImageView的方法步骤

1.新建一个RoundImage.java文件

package com.jhg.freshman;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.Drawable;import android.os.Build;import android.util.AttributeSet;import android.util.TypedValue;import android.widget.ImageView;    public class RoundImageView extends android.support.v7.widget.AppCompatImageView {        /**         * 圆形模式         */        private static final int MODE_CIRCLE = 1;        /**         * 普通模式         */        private static final int MODE_NONE = 0;        /**         * 圆角模式         */        private static final int MODE_ROUND = 2;        private Paint mPaint;        private int currMode = 0;        /**         * 圆角半径         */        private int currRound = dp2px(10);        public RoundImageView(Context context) {            super(context);            initViews();        }        public RoundImageView(Context context, AttributeSet attrs) {            this(context, attrs, 0);        }        public RoundImageView(Context context, AttributeSet attrs, int defStyleAttr) {            super(context, attrs, defStyleAttr);            obtainStyledAttrs(context, attrs, defStyleAttr);            initViews();        }        private void obtainStyledAttrs(Context context, AttributeSet attrs, int defStyleAttr) {            TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.RoundImageView, defStyleAttr, 0);            currMode = a.hasValue(R.styleable.RoundImageView_type) ? a.getInt(R.styleable.RoundImageView_type, MODE_NONE) : MODE_NONE;            currRound = a.hasValue(R.styleable.RoundImageView_radius) ? a.getDimensionPixelSize(R.styleable.RoundImageView_radius, currRound) : currRound;            a.recycle();        }        private void initViews() {            mPaint = new Paint(Paint.ANTI_ALIAS_FLAG | Paint.DITHER_FLAG);        }        @Override        protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {            /**             * 当模式为圆形模式的时候，我们强制让宽高一致             */            if (currMode == MODE_CIRCLE) {                super.onMeasure(widthMeasureSpec, heightMeasureSpec);                int result = Math.min(getMeasuredHeight(), getMeasuredWidth());                setMeasuredDimension(result, result);            } else {                super.onMeasure(widthMeasureSpec, heightMeasureSpec);            }        }        @Override        protected void onDraw(Canvas canvas) {            Drawable mDrawable = getDrawable();            Matrix mDrawMatrix = getImageMatrix();            if (mDrawable == null) {                return; // couldn't resolve the URI            }            if (mDrawable.getIntrinsicWidth() == 0 || mDrawable.getIntrinsicHeight() == 0) {                return;     // nothing to draw (empty bounds)            }            if (mDrawMatrix == null && getPaddingTop() == 0 && getPaddingLeft() == 0) {                mDrawable.draw(canvas);            } else {                final int saveCount = canvas.getSaveCount();                canvas.save();                if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN) {                    if (getCropToPadding()) {                        final int scrollX = getScrollX();                        final int scrollY = getScrollY();                        canvas.clipRect(scrollX + getPaddingLeft(), scrollY + getPaddingTop(),                                scrollX + getRight() - getLeft() - getPaddingRight(),                                scrollY + getBottom() - getTop() - getPaddingBottom());                    }                }                canvas.translate(getPaddingLeft(), getPaddingTop());                if (currMode == MODE_CIRCLE) {//当为圆形模式的时候                    Bitmap bitmap = drawable2Bitmap(mDrawable);                    mPaint.setShader(new BitmapShader(bitmap, Shader.TileMode.CLAMP, Shader.TileMode.CLAMP));                    canvas.drawCircle(getWidth() / 2, getHeight() / 2, getWidth() / 2, mPaint);                } else if (currMode == MODE_ROUND) {//当为圆角模式的时候                    Bitmap bitmap = drawable2Bitmap(mDrawable);                    mPaint.setShader(new BitmapShader(bitmap, Shader.TileMode.CLAMP, Shader.TileMode.CLAMP));                    canvas.drawRoundRect(new RectF(getPaddingLeft(), getPaddingTop(), getWidth() - getPaddingRight(), getHeight() - getPaddingBottom()),                            currRound, currRound, mPaint);                } else {                    if (mDrawMatrix != null) {                        canvas.concat(mDrawMatrix);                    }                    mDrawable.draw(canvas);                }                canvas.restoreToCount(saveCount);            }        }        /**         * drawable转换成bitmap         */        private Bitmap drawable2Bitmap(Drawable drawable) {            if (drawable == null) {                return null;            }            Bitmap bitmap = Bitmap.createBitmap(getWidth(), getHeight(), Bitmap.Config.ARGB_8888);            Canvas canvas = new Canvas(bitmap);            //根据传递的scaletype获取matrix对象，设置给bitmap            Matrix matrix = getImageMatrix();            if (matrix != null) {                canvas.concat(matrix);            }            drawable.draw(canvas);            return bitmap;        }        private int dp2px(float value) {            return (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, value, getResources().getDisplayMetrics());        }    }

2.在Value下新建一个attrs.xml文件

<?xml version="1.0" encoding="utf-8"?>                                                    ssss

3.在layout布局文件中使用RoundImage控件

更多相关文章

随机推荐