自定义的形状ImageView

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.Drawable; import android.util.AttributeSet; import android.widget.ImageView; import com.bumptech.glide.load.resource.bitmap.GlideBitmapDrawable; import com.isgo.isgogallery.R; public class RectangleView extends ImageView{ public static int SHAPE_REC = 1; // 矩形 public static int SHAPE_CIRCLE = 2; // 圆形 public static int SHAPE_OVAL = 3; // 椭圆 private float mBorderSize = 0; // 边框大小,默认为０，即无边框 private int mBorderColor = Color.WHITE; // 边框颜色，默认为白色 private int mShape = SHAPE_REC; // 形状，默认为直接矩形 private float mRoundRadius = 0; // 矩形的圆角半径,默认为０，即直角矩形 private Paint mBorderPaint = new Paint(Paint.ANTI_ALIAS_FLAG); private RectF mViewRect = new RectF(); // imageview的矩形区域 private RectF mBorderRect = new RectF(); // 边框的矩形区域 private final Matrix mShaderMatrix = new Matrix(); private Paint mBitmapPaint = new Paint(); private BitmapShader mBitmapShader; private Bitmap mBitmap; public RectangleView(Context context, AttributeSet attrs) { this(context, attrs, 0); } public RectangleView(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); // 虽然此处会调用setImageDrawable，但此时成员变量还未被正确初始化 init(attrs); mBorderPaint.setStyle(Paint.Style.STROKE); mBorderPaint.setStrokeWidth(mBorderSize); mBorderPaint.setColor(mBorderColor); mBorderPaint.setAntiAlias(true); mBitmapPaint.setAntiAlias(true); super.setScaleType(ScaleType.CENTER_CROP); // 固定为CENTER_CROP，其他不生效 } @Override public void setImageResource(int resId) { super.setImageResource(resId); mBitmap = getBitmapFromDrawable(getDrawable()); setupBitmapShader(); } @Override public void setBackgroundResource(int resid) { super.setBackgroundResource(resid); mBitmap = getBitmapFromDrawable( getResources().getDrawable(resid)); setupBitmapShader(); } @Override public void setBackgroundDrawable(Drawable background) { super.setBackgroundDrawable(background); mBitmap = getBitmapFromDrawable(background); setupBitmapShader(); } @Override public void setBackground(Drawable background) { super.setBackground(background); mBitmap = getBitmapFromDrawable(background); setupBitmapShader(); } private Bitmap getBitmapFromDrawable(Drawable drawable) { if(drawable != null){ if(drawable instanceof GlideBitmapDrawable){ return ((GlideBitmapDrawable)drawable).getBitmap(); }else if(drawable instanceof BitmapDrawable){ return ((BitmapDrawable)drawable).getBitmap(); } } return null; } @Override public void setImageDrawable(Drawable drawable) { super.setImageDrawable(drawable); mBitmap = getBitmapFromDrawable(drawable); setupBitmapShader(); } @Override public void setScaleType(ScaleType scaleType) { if (scaleType != ScaleType.CENTER_CROP) { throw new IllegalArgumentException(String.format("ScaleType %s not supported.", scaleType)); } } private void init(AttributeSet attrs) { TypedArray a = getContext().obtainStyledAttributes(attrs, R.styleable.RectangleView); mShape = a.getInt(R.styleable.RectangleView_shape, mShape); mRoundRadius = a.getDimension(R.styleable.RectangleView_round_radius, mRoundRadius); mBorderSize = a.getDimension(R.styleable.RectangleView_border_size, mBorderSize); mBorderColor = a.getColor(R.styleable.RectangleView_border_color1, mBorderColor); a.recycle(); } /** * 对于普通的view,在执行到onDraw()时，背景图已绘制完成 * <p/> * 对于ViewGroup,当它没有背景时直接调用的是dispatchDraw()方法, 而绕过了draw()方法， * 当它有背景的时候就调用draw()方法，而draw()方法里包含了dispatchDraw()方法的调用， */ @Override public void onDraw(Canvas canvas) { if (getDrawable() != null) { if (mShape == SHAPE_CIRCLE) { canvas.drawCircle(getWidth() / 2, getHeight() / 2, Math.min(getWidth(), getHeight()) / 2, mBitmapPaint); } else if (mShape == SHAPE_OVAL) { canvas.drawOval(mViewRect, mBitmapPaint); } else { canvas.drawRoundRect(mViewRect, mRoundRadius, mRoundRadius, mBitmapPaint); } } if (mBorderSize > 0) { // 绘制边框 if (mShape == SHAPE_CIRCLE) { canvas.drawCircle(mViewRect.right / 2, mViewRect.bottom / 2, Math.min(mViewRect.right, mViewRect.bottom) / 2 - mBorderSize / 2, mBorderPaint); } else if (mShape == SHAPE_OVAL) { canvas.drawOval(mBorderRect, mBorderPaint); } else { canvas.drawRoundRect(mBorderRect, mRoundRadius, mRoundRadius, mBorderPaint); } } } @Override protected void onSizeChanged(int w, int h, int oldw, int oldh) { super.onSizeChanged(w, h, oldw, oldh); initRect(); setupBitmapShader(); } // 不能在onLayout()调用invalidate()，否则导致绘制异常。（setupBitmapShader()中调用了invalidate()） @Override protected void onLayout(boolean changed, int left, int top, int right, int bottom) { super.onLayout(changed, left, top, right, bottom); // initRect(); // setupBitmapShader(); } private void setupBitmapShader() { // super(context, attrs, defStyle)调用setImageDrawable时,成员变量还未被正确初始化 if (mBitmapPaint == null) { return; } if (mBitmap == null) { invalidate(); return; } mBitmapShader = new BitmapShader(mBitmap, Shader.TileMode.CLAMP, Shader.TileMode.CLAMP); mBitmapPaint.setShader(mBitmapShader); // 固定为CENTER_CROP,使图片在ｖｉｅｗ中居中并裁剪 mShaderMatrix.set(null); // 缩放到高或宽　与view的高或宽　匹配 float scale = Math.max(getWidth() * 1f / mBitmap.getWidth(), getHeight() * 1f / mBitmap.getHeight()); // 由于BitmapShader默认是从画布的左上角开始绘制，所以把其平移到画布中间，即居中 float dx = (getWidth() - mBitmap.getWidth() * scale) / 2; float dy = (getHeight() - mBitmap.getHeight() * scale) / 2; mShaderMatrix.setScale(scale, scale); mShaderMatrix.postTranslate(dx, dy); mBitmapShader.setLocalMatrix(mShaderMatrix); invalidate(); } //　设置图片的绘制区域 private void initRect() { mViewRect.top = 0; mViewRect.left = 0; mViewRect.right = getWidth(); // 宽度 mViewRect.bottom = getHeight(); // 高度 // 边框的矩形区域不能等于ImageView的矩形区域，否则边框的宽度只显示了一半 mBorderRect.top = mBorderSize / 2; mBorderRect.left = mBorderSize / 2; mBorderRect.right = getWidth() - mBorderSize / 2; mBorderRect.bottom = getHeight() - mBorderSize / 2; } public int getShape() { return mShape; } public void setShape(int shape) { mShape = shape; } public float getBorderSize() { return mBorderSize; } public void setBorderSize(int mBorderSize) { this.mBorderSize = mBorderSize; mBorderPaint.setStrokeWidth(mBorderSize); initRect(); invalidate(); } public int getBorderColor() { return mBorderColor; } public void setBorderColor(int mBorderColor) { this.mBorderColor = mBorderColor; mBorderPaint.setColor(mBorderColor); invalidate(); } public float getRoundRadius() { return mRoundRadius; } public void setRoundRadius(float mRoundRadius) { this.mRoundRadius = mRoundRadius; invalidate(); } }