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public class ShadowViewCard extends FrameLayout {private static final int DEFAULT_VALUE_SHADOW_COLOR = R.color.shadow_default_color;private static final int DEFAULT_VALUE_SHADOW_CARD_COLOR = R.color.shadow_card_default_color;private static final int DEFAULT_VALUE_SHADOW_ROUND = 0;

private static final int DEFAULT_VALUE_SHADOW_RADIUS = 10;private static final int DEFAULT_VALUE_SHADOW_TOP_HEIGHT = 5;private static final int DEFAULT_VALUE_SHADOW_LEFT_HEIGHT = 5;private static final int DEFAULT_VALUE_SHADOW_RIGHT_HEIGHT = 5;private static final int DEFAULT_VALUE_SHADOW_BOTTOM_HEIGHT = 5;private static final int DEFAULT_VALUE_SHADOW_OFFSET_Y = 0;private static final int DEFAULT_VALUE_SHADOW_OFFSET_X = DEFAULT_VALUE_SHADOW_TOP_HEIGHT / 3;

private int shadowRound;private int shadowColor;private int shadowCardColor;private int shadowRadius;private int shadowOffsetY;private int shadowOffsetX;private int shadowTopHeight;private int shadowLeftHeight;private int shadowRightHeight;private int shadowBottomHeight;

public ShadowViewCard(Context context) {this(context, null);}

public ShadowViewCard(Context context, AttributeSet attrs) {this(context, attrs, 0);}

public ShadowViewCard(Context context, AttributeSet attrs, int defStyleAttr) {super(context, attrs, defStyleAttr);initView(context, attrs);}

private void initView(Context context, AttributeSet attrs) {TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.ShadowViewCard);shadowRound = a.getDimensionPixelSize(R.styleable.ShadowViewCard_shadowRound, DEFAULT_VALUE_SHADOW_ROUND);shadowColor = a.getColor(R.styleable.ShadowViewCard_shadowColor, getResources().getColor(DEFAULT_VALUE_SHADOW_COLOR));shadowCardColor = a.getColor(R.styleable.ShadowViewCard_shadowCardColor, getResources().getColor(DEFAULT_VALUE_SHADOW_CARD_COLOR));shadowTopHeight = a.getDimensionPixelSize(R.styleable.ShadowViewCard_shadowTopHeight, dp2px(getContext(), DEFAULT_VALUE_SHADOW_TOP_HEIGHT));shadowRightHeight = a.getDimensionPixelSize(R.styleable.ShadowViewCard_shadowRightHeight, dp2px(getContext(), DEFAULT_VALUE_SHADOW_RIGHT_HEIGHT));shadowLeftHeight = a.getDimensionPixelSize(R.styleable.ShadowViewCard_shadowLeftHeight, dp2px(getContext(), DEFAULT_VALUE_SHADOW_LEFT_HEIGHT));shadowBottomHeight = a.getDimensionPixelSize(R.styleable.ShadowViewCard_shadowBottomHeight, dp2px(getContext(), DEFAULT_VALUE_SHADOW_BOTTOM_HEIGHT));shadowOffsetY = a.getDimensionPixelSize(R.styleable.ShadowViewCard_shadowOffsetY, dp2px(getContext(), DEFAULT_VALUE_SHADOW_OFFSET_Y));shadowOffsetX = a.getDimensionPixelSize(R.styleable.ShadowViewCard_shadowOffsetX, dp2px(getContext(), DEFAULT_VALUE_SHADOW_OFFSET_X));shadowRadius = a.getInteger(R.styleable.ShadowViewCard_shadowRadius, DEFAULT_VALUE_SHADOW_RADIUS);a.recycle();setPadding(shadowLeftHeight, shadowTopHeight, sha

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dowRightHeight, shadowBottomHeight);setLayerType(LAYER_TYPE_SOFTWARE, null);}

public static int dp2px(Context context, float dipValue) {final float scale = context.getResources().getDisplayMetrics().density;return (int) (dipValue * scale + 0.5f);}

@Overrideprotected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {super.onMeasure(widthMeasureSpec, heightMeasureSpec);}

@Overrideprotected void onDraw(Canvas canvas) {super.onDraw(canvas);}

@Overrideprotected void dispatchDraw(Canvas canvas) {Paint shadowPaint = new Paint();shadowPaint.setColor(Color.WHITE);shadowPaint.setStyle(Paint.Style.FILL);shadowPaint.setAntiAlias(true);float left = shadowLeftHeight;float top = shadowTopHeight;float right = getWidth() - shadowRightHeight;float bottom = getHeight() - shadowBottomHeight;shadowPaint.setShadowLayer(shadowRadius, shadowOffsetX, shadowOffsetX, shadowColor);RectF rectF = new RectF(left, top, right, bottom);canvas.drawRoundRect(rectF, shadowRound, shadowRound, shadowPaint);canvas.save();super.dispatchDraw(canvas);}}

attr.xml

color.xml

<color name="shadow_default_color">#1a000000</color><color name="shadow_card_default_color">#ffffff</color>

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