Android使用CircleImageView实现圆形头像的方法

<?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>

<?xml version="1.0" encoding="utf-8"?><RelativeLayout   xmlns:android="http://schemas.android.com/apk/res/android"  xmlns:tools="http://schemas.android.com/tools"  android:layout_width="match_parent"  android:layout_height="match_parent"  tools:context="com.example.icontest.MainActivity">  <circleimageview.CircleImageView    xmlns:app="http://schemas.android.com/apk/res-auto"    android:id="@+id/circleImageView"    android:layout_width="100dp"    android:layout_height="100dp"    android:layout_centerHorizontal="true"    android:src="@mipmap/ic_launcher"    app:border_width="2dp"    app:border_color="#ccc"     /></RelativeLayout>

CircleImageView icon;icon= (CircleImageView) findViewById(R.id.circleImageView);

package circleimageview;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.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;import com.example.icontest.R;public class CircleImageView extends ImageView {  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 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 int mBorderColor = DEFAULT_BORDER_COLOR;  private int mBorderWidth = DEFAULT_BORDER_WIDTH;  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);  }  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_border_width, DEFAULT_BORDER_WIDTH);   mBorderColor = a.getColor(R.styleable.CircleImageView_border_color, DEFAULT_BORDER_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 (getDrawable() == null) {     return;   }   canvas.drawCircle(getWidth() / 2, getHeight() / 2, mDrawableRadius, mBitmapPaint);   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();  }  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);  }}