• 自定义View 水印布局 WaterMark 前景色 MD


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    自定义View 水印布局 WaterMark 前景色 MD


    目录

    第一种实现方式

    项目中的使用案例

    项目中要求在所有页面都添加水印,这种情况下可以在BaseActivity中将水印布局设为根布局

    前景色样式:
    mark
    背景色样式:
    mark

    布局:

    <com.bqt.lock.MarkFrameLayout
        xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:app="http://schemas.android.com/apk/res-auto"
        android:id="@+id/mark_layout"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:mark_is_foreground="false"
        app:mark_show_value="包青天"
        app:mark_textcolor="#fff">
    
        <TextView
            android:id="@+id/tv"
            android:layout_width="match_parent"
            android:layout_height="100dp"
            android:background="#f00"
            android:gravity="center"/>
    
        <ImageView
            android:layout_width="match_parent"
            android:layout_height="100dp"
            android:layout_marginTop="200dp"
            android:scaleType="centerCrop"
            android:src="@drawable/icon"/>
    
    </com.bqt.lock.MarkFrameLayout>

    水印布局 MarkFrameLayout

    绘制水印时,可以选择在onDrawForeground上绘制前景色(盖在所有View的上面),也可以选择在onDraw上绘制背景色(会被所有View的背景遮盖)。
    如果需要用到继承自其他其他 Layout 的水印布局,则只需将继承的类改为RelativeLayoutLinearLayout即可,其他什么都不需要更改。

    public class MarkFrameLayout extends FrameLayout {
    
        private static final int DEFAULT_DEGRESES = -15;//水印倾斜角度
        private static final int DEFAULT_MARK_PAINT_COLOR = Color.parseColor("#FFCCCCCC");//水印颜色
        private static final int DEFAULT_ALPHA = (int) (0.5 * 255);//水印透明度
        private static final String DEFAULT_MARK_SHOW_VALUE = "[水印]";//水印内容
    
        private boolean showMark = true;
        private float mMarkTextSize;
        private int mMarkTextColor;
        private boolean mMarkLayerIsForeground; //水印绘制在控件背景上,还是前景色上
        private float mDegrees;
        private int mVerticalSpacing;
        private int mHorizontalSpacing;
        private int mMarkPainAlpha;
        private String mMarkValue;
        private TextPaint mMarkPaint;
        private Bitmap mMarkBitmap;
    
        public MarkFrameLayout(@NonNull Context context) {
            this(context, null);
        }
    
        public MarkFrameLayout(@NonNull Context context, @Nullable AttributeSet attrs) {
            super(context, attrs);
            if (showMark) {
                int defaultMarkTextSize = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_SP, 12, getResources().getDisplayMetrics());
                int defaultSpacing = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 24, getResources().getDisplayMetrics());
    
                TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.MarkFrameLayout);
                mDegrees = a.getInteger(R.styleable.MarkFrameLayout_mark_rotate_degrees, DEFAULT_DEGRESES);
                mMarkTextColor = a.getColor(R.styleable.MarkFrameLayout_mark_textcolor, DEFAULT_MARK_PAINT_COLOR);
                mMarkTextSize = a.getDimension(R.styleable.MarkFrameLayout_mark_textsize, defaultMarkTextSize);
                mMarkPainAlpha = a.getInt(R.styleable.MarkFrameLayout_mark_alpha, DEFAULT_ALPHA);
                mMarkLayerIsForeground = a.getBoolean(R.styleable.MarkFrameLayout_mark_is_foreground, true);//默认绘制在前景色上
                mHorizontalSpacing = (int) a.getDimension(R.styleable.MarkFrameLayout_mark_hor_spacing, defaultSpacing);
                mVerticalSpacing = (int) a.getDimension(R.styleable.MarkFrameLayout_mark_ver_spacing, defaultSpacing);
                mMarkValue = a.getString(R.styleable.MarkFrameLayout_mark_show_value);
                mMarkValue = TextUtils.isEmpty(mMarkValue) ? DEFAULT_MARK_SHOW_VALUE : mMarkValue;
    
                a.recycle();
                initWaterPaint();
                setForeground(new ColorDrawable(Color.TRANSPARENT)); //重置前景色透明
            }
        }
    
        @Override
        public void onDrawForeground(Canvas canvas) {
            super.onDrawForeground(canvas);
            if (showMark && mMarkLayerIsForeground) {
                drawMark(canvas); //绘制前景色
            }
        }
    
        @Override
        protected void onDraw(Canvas canvas) {
            super.onDraw(canvas);
            if (showMark && !mMarkLayerIsForeground) {
                drawMark(canvas); //绘制被景色
            }
        }
    
        private void initWaterPaint() {
            //初始化Mark的Paint
            mMarkPaint = new TextPaint(Paint.ANTI_ALIAS_FLAG); //mMarkPaint.setAntiAlias(true)
            mMarkPaint.setColor(mMarkTextColor);
            mMarkPaint.setAlpha(mMarkPainAlpha);
            mMarkPaint.setTextSize(mMarkTextSize);
            //初始化MarkBitmap
            Paint.FontMetrics fontMetrics = mMarkPaint.getFontMetrics();
            int textHeight = (int) (fontMetrics.bottom - fontMetrics.top);
            int textLength = (int) mMarkPaint.measureText(mMarkValue);
            mMarkBitmap = Bitmap.createBitmap(textLength + 2 * mHorizontalSpacing,
                    textHeight + mVerticalSpacing * 2, Bitmap.Config.ARGB_8888);
            Canvas canvas = new Canvas(mMarkBitmap);
            canvas.drawText(mMarkValue, mHorizontalSpacing, mVerticalSpacing, mMarkPaint);
        }
    
        private void drawMark(Canvas canvas) {
            int maxSize = Math.max(getMeasuredWidth(), getMeasuredHeight());
            mMarkPaint.setShader(new BitmapShader(mMarkBitmap, Shader.TileMode.REPEAT, Shader.TileMode.REPEAT));
            canvas.save();
            canvas.translate(-(maxSize - getMeasuredWidth()) / 2, 0);
            canvas.rotate(mDegrees, maxSize / 2, maxSize / 2);
            canvas.drawRect(new RectF(0, 0, maxSize, maxSize), mMarkPaint);
            canvas.restore();
        }
    
        public void setShowMark(boolean showMark) {
            this.showMark = showMark;
            invalidate();
        }
    }

    自定义属性

    <?xml version="1.0" encoding="utf-8"?>
    <resources>
        <declare-styleable name="MarkFrameLayout">
            <attr name="mark_rotate_degrees" format="integer"/>
            <attr name="mark_textcolor" format="color|reference"/>
            <attr name="mark_textsize" format="dimension"/>
            <attr name="mark_alpha" format="integer"/>
            <attr name="mark_is_foreground" format="boolean"/>
            <attr name="mark_hor_spacing" format="dimension"/>
            <attr name="mark_ver_spacing" format="dimension"/>
            <attr name="mark_show_value" format="string"/>
        </declare-styleable>
    
    </resources>

    第二种实现方式

    参考

    使用案例

    FrameLayout rootView = findViewById(R.id.layout);
    rootView.setForeground(new WaterMarkBg(this, labels, -10, 12));

    自定义 Drawable

    public class WaterMarkBg extends Drawable {
    
        private Paint paint = new Paint();
        private List<String> labels;
        private Context context;
        private int degress;//角度
        private int fontSize;//字体大小 单位sp
    
        /**
         * 初始化构造
         *
         * @param context  上下文
         * @param labels   水印文字列表 多行显示支持
         * @param degress  水印角度
         * @param fontSize 水印文字大小
         */
        public WaterMarkBg(Context context, List<String> labels, int degress, int fontSize) {
            this.labels = labels;
            this.context = context;
            this.degress = degress;
            this.fontSize = fontSize;
        }
    
        @Override
        public void draw(@NonNull Canvas canvas) {
            int width = getBounds().right;
            int height = getBounds().bottom;
    
            canvas.drawColor(Color.TRANSPARENT);
            paint.setColor(Color.GRAY);
            paint.setAlpha((int) (0.5 * 255));
            paint.setAntiAlias(true);
            paint.setTextSize(sp2px(context, fontSize));
            canvas.save();
            canvas.rotate(degress);
            float textWidth = paint.measureText(labels.get(0));
            int index = 0;
            for (int positionY = height / 10; positionY <= height; positionY += height / 10 + 80) {
                float fromX = -width + (index++ % 2) * textWidth;
                for (float positionX = fromX; positionX < width; positionX += textWidth * 2) {
                    int spacing = 0;//间距
                    for (String label : labels) {
                        canvas.drawText(label, positionX, positionY + spacing, paint);
                        spacing = spacing + 50;
                    }
    
                }
            }
            canvas.restore();
        }
    
        @Override
        public void setAlpha(@IntRange(from = 0, to = 255) int alpha) {
    
        }
    
        @Override
        public void setColorFilter(@Nullable ColorFilter colorFilter) {
    
        }
    
        @Override
        public int getOpacity() {
            return PixelFormat.UNKNOWN;
        }
    
        private static int sp2px(Context context, float spValue) {
            final float fontScale = context.getResources().getDisplayMetrics().scaledDensity;
            return (int) (spValue * fontScale + 0.5f);
        }
    }

    2018-10-13 11:59:36 星期六

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  • 原文地址:https://www.cnblogs.com/baiqiantao/p/9782665.html
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