圆形ImageView

控件来源https://github.com/hdodenhof/CircleImageView
这里说一下简单实用方法
自己的项目中使用的话，需要写一个类class CircleImageView extends ImageView :
可能获取有的Android版本不一致,继承的类改为:
android.support.v7.widget.AppCompatImageView
如果需要使用,复制粘贴就行(记得改包名)
效果贴图:

下面是类的具体代码:
package com.example.autum.layotdemo.customview;

import 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.ColorInt;
import android.support.annotation.ColorRes;
import android.support.annotation.DrawableRes;
import android.util.AttributeSet;

import com.example.autum.layotdemo.R;

public class CircleImageView extends android.support.v7.widget.AppCompatImageView {

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;
private boolean mDisableCircularTransformation;

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 (mDisableCircularTransformation) {
        super.onDraw(canvas);
        return;
    }

    if (mBitmap == null) {
        return;
    }

    if (mFillColor != Color.TRANSPARENT) {
        canvas.drawCircle(mDrawableRect.centerX(), mDrawableRect.centerY(), mDrawableRadius, mFillPaint);
    }
    canvas.drawCircle(mDrawableRect.centerX(), mDrawableRect.centerY(), mDrawableRadius, mBitmapPaint);
    if (mBorderWidth > 0) {
        canvas.drawCircle(mBorderRect.centerX(), mBorderRect.centerY(), mBorderRadius, mBorderPaint);
    }
}

@Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
    super.onSizeChanged(w, h, oldw, oldh);
    setup();
}

@Override
public void setPadding(int left, int top, int right, int bottom) {
    super.setPadding(left, top, right, bottom);
    setup();
}

@Override
public void setPaddingRelative(int start, int top, int end, int bottom) {
    super.setPaddingRelative(start, top, end, bottom);
    setup();
}

public int getBorderColor() {
    return mBorderColor;
}

public void setBorderColor(@ColorInt int borderColor) {
    if (borderColor == mBorderColor) {
        return;
    }

    mBorderColor = borderColor;
    mBorderPaint.setColor(mBorderColor);
    invalidate();
}

/**
 * @deprecated Use {@link #setBorderColor(int)} instead
 */
@Deprecated
public void setBorderColorResource(@ColorRes int borderColorRes) {
    setBorderColor(getContext().getResources().getColor(borderColorRes));
}

/**
 * Return the color drawn behind the circle-shaped drawable.
 *
 * @return The color drawn behind the drawable
 *
 * @deprecated Fill color support is going to be removed in the future
 */
@Deprecated
public int getFillColor() {
    return mFillColor;
}

/**
 * Set a color to be drawn behind the circle-shaped drawable. Note that
 * this has no effect if the drawable is opaque or no drawable is set.
 *
 * @param fillColor The color to be drawn behind the drawable
 *
 * @deprecated Fill color support is going to be removed in the future
 */
@Deprecated
public void setFillColor(@ColorInt int fillColor) {
    if (fillColor == mFillColor) {
        return;
    }

    mFillColor = fillColor;
    mFillPaint.setColor(fillColor);
    invalidate();
}

/**
 * Set a color to be drawn behind the circle-shaped drawable. Note that
 * this has no effect if the drawable is opaque or no drawable is set.
 *
 * @param fillColorRes The color resource to be resolved to a color and
 *                     drawn behind the drawable
 *
 * @deprecated Fill color support is going to be removed in the future
 */
@Deprecated
public void setFillColorResource(@ColorRes int fillColorRes) {
    setFillColor(getContext().getResources().getColor(fillColorRes));
}

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();
}

public boolean isDisableCircularTransformation() {
    return mDisableCircularTransformation;
}

public void setDisableCircularTransformation(boolean disableCircularTransformation) {
    if (mDisableCircularTransformation == disableCircularTransformation) {
        return;
    }

    mDisableCircularTransformation = disableCircularTransformation;
    initializeBitmap();
}

@Override
public void setImageBitmap(Bitmap bm) {
    super.setImageBitmap(bm);
    initializeBitmap();
}

@Override
public void setImageDrawable(Drawable drawable) {
    super.setImageDrawable(drawable);
    initializeBitmap();
}

@Override
public void setImageResource(@DrawableRes int resId) {
    super.setImageResource(resId);
    initializeBitmap();
}

@Override
public void setImageURI(Uri uri) {
    super.setImageURI(uri);
    initializeBitmap();
}

@Override
public void setColorFilter(ColorFilter cf) {
    if (cf == mColorFilter) {
        return;
    }

    mColorFilter = cf;
    applyColorFilter();
    invalidate();
}

@Override
public ColorFilter getColorFilter() {
    return mColorFilter;
}

private void applyColorFilter() {
    if (mBitmapPaint != null) {
        mBitmapPaint.setColorFilter(mColorFilter);
    }
}

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 initializeBitmap() {
    if (mDisableCircularTransformation) {
        mBitmap = null;
    } else {
        mBitmap = getBitmapFromDrawable(getDrawable());
    }
    setup();
}

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(calculateBounds());
    mBorderRadius = Math.min((mBorderRect.height() - mBorderWidth) / 2.0f, (mBorderRect.width() - mBorderWidth) / 2.0f);

    mDrawableRect.set(mBorderRect);
    if (!mBorderOverlay && mBorderWidth > 0) {
        mDrawableRect.inset(mBorderWidth - 1.0f, mBorderWidth - 1.0f);
    }
    mDrawableRadius = Math.min(mDrawableRect.height() / 2.0f, mDrawableRect.width() / 2.0f);

    applyColorFilter();
    updateShaderMatrix();
    invalidate();
}

private RectF calculateBounds() {
    int availableWidth  = getWidth() - getPaddingLeft() - getPaddingRight();
    int availableHeight = getHeight() - getPaddingTop() - getPaddingBottom();

    int sideLength = Math.min(availableWidth, availableHeight);

    float left = getPaddingLeft() + (availableWidth - sideLength) / 2f;
    float top = getPaddingTop() + (availableHeight - sideLength) / 2f;

    return new RectF(left, top, left + sideLength, top + sideLength);
}

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);
}

}

然后在项目中的values资源文件夹下的attr.xml中添加以下代码(如果没有文件请自行创建):
—这里可能xml语句显示不了,加个截图,方便观看,其实代码也不多,可手打!!!









然后就能使用了,如果有不能使用的请转正式文档:https://github.com/hdodenhof/CircleImageView!!!