

要實現這兩種效果,需要自定義View,並且有兩種實現方式.
第一種:
public class BitmapShaders extends View
{
private BitmapShader bitmapShader = null;
private Bitmap bitmap = null;
private Paint paint = null;
private ShapeDrawable shapeDrawable = null;
private int BitmapWidth = 0;
private int BitmapHeight = 0;
public BitmapShaders(Context context)
{
super(context);
//得到圖像
bitmap = ((BitmapDrawable) getResources().getDrawable(R.drawable.h)).getBitmap();
BitmapWidth = bitmap.getWidth();
BitmapHeight = bitmap.getHeight();
//構造渲染器BitmapShader
bitmapShader = new BitmapShader(bitmap,Shader.TileMode.MIRROR,Shader.TileMode.REPEAT);
}
@Override
protected void onDraw(Canvas canvas)
{
super.onDraw(canvas);
//將圖片裁剪為橢圓形
//構建ShapeDrawable對象並定義形狀為橢圓
shapeDrawable = new ShapeDrawable(new OvalShape());
//得到畫筆並設置渲染器
shapeDrawable.getPaint().setShader(bitmapShader);
//設置顯示區域
shapeDrawable.setBounds(20, 20,700,BitmapHeight);//可見區域
//繪制shapeDrawable
shapeDrawable.draw(canvas);
}
}
第二種:
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 = 1; //尺寸
private static final int DEFAULT_BORDER_WIDTH = 0; //邊框寬度
private static final int DEFAULT_BORDER_COLOR = Color.BLACK; //邊框顏色
private final RectF mDrawableRect = new RectF();//圖像矩形
private final RectF mBorderRect = new RectF(); //邊框矩形
private final Matrix mShaderMatrix = new Matrix(); //矩陣
private final Paint mBitmapPaint = new Paint(); //圖像畫筆
private final Paint mBorderPaint = new Paint();//邊框畫筆
private int mBorderColor = DEFAULT_BORDER_COLOR; //邊框顏色
private int mBorderWidth = DEFAULT_BORDER_WIDTH; //邊框寬度
private Bitmap mBitmap; //圖片
private BitmapShader mBitmapShader; //渲染為圓�?
private int mBitmapWidth; //位圖寬度
private int mBitmapHeight; //位圖高度
private float mDrawableRadius; //圖片半徑
private float mBorderRadius; //邊框半徑
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);//按比例擴�?/縮小圖片的size居中顯示,使得圖片的高等於View的高,使得圖片寬等於或大於View的寬
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
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() {
Log.e("info","進入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);
}
