feat(*): 添加水印工具类

Author: AndroidCoderPeng

lite/src/main/java/com/pengxh/kt/lite/annotations/WaterMarkPosition.kt

@@ -0,0 +1,31 @@
+package com.pengxh.kt.lite.annotations
+
+@Retention(AnnotationRetention.SOURCE)
+annotation class WaterMarkPosition {
+    companion object {
+        /**
+         * 左上
+         */
+        const val LEFT_TOP = 1
+
+        /**
+         * 右上
+         */
+        const val RIGHT_TOP = 2
+
+        /**
+         * 左下
+         */
+        const val LEFT_BOTTOM = 3
+
+        /**
+         * 右下
+         */
+        const val RIGHT_BOTTOM = 4
+
+        /**
+         * 中间
+         */
+        const val CENTER = 0
+    }
+}

lite/src/main/java/com/pengxh/kt/lite/utils/WaterMarkEngine.kt

@@ -0,0 +1,191 @@
+package com.pengxh.kt.lite.utils
+
+import android.content.Context
+import android.graphics.Bitmap
+import android.graphics.Canvas
+import android.graphics.Color
+import android.graphics.Rect
+import android.graphics.Typeface
+import android.text.TextPaint
+import androidx.lifecycle.Lifecycle
+import androidx.lifecycle.LifecycleOwner
+import androidx.lifecycle.LifecycleRegistry
+import androidx.lifecycle.lifecycleScope
+import com.pengxh.kt.lite.annotations.WaterMarkPosition
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.launch
+import kotlinx.coroutines.withContext
+import java.io.File
+import java.io.FileOutputStream
+
+/**
+ * 绘制水印
+ */
+class WaterMarkEngine : LifecycleOwner {
+
+    private val registry = LifecycleRegistry(this)
+    private val textPaint by lazy { TextPaint() }
+    private val textRect by lazy { Rect() }
+
+    private lateinit var context: Context
+    private lateinit var originalBitmap: Bitmap
+    private lateinit var marker: String
+    private var textColor = Color.WHITE
+    private var textSize = 16f
+    private var textPadding = 10f
+    private lateinit var addedListener: OnWaterMarkerAddedListener
+    private var position = WaterMarkPosition.RIGHT_BOTTOM
+    private lateinit var fileName: String
+
+    /**
+     * 设置上下文
+     * */
+    fun setContext(context: Context): WaterMarkEngine {
+        this.context = context
+        return this
+    }
+
+    /**
+     * 设置原始Bitmap
+     * */
+    fun setOriginalBitmap(bitmap: Bitmap): WaterMarkEngine {
+        this.originalBitmap = bitmap
+        return this
+    }
+
+    /**
+     * 设置水印文字
+     * */
+    fun setTextMaker(marker: String): WaterMarkEngine {
+        this.marker = marker
+        return this
+    }
+
+    /**
+     * 设置水印文字颜色
+     * */
+    fun setTextColor(textColor: Int): WaterMarkEngine {
+        this.textColor = textColor
+        return this
+    }
+
+    /**
+     * 设置水印文字大小
+     * */
+    fun setTextSize(textSize: Float): WaterMarkEngine {
+        this.textSize = textSize
+        return this
+    }
+
+    /**
+     * 设置水印文字位置
+     * */
+    fun setMarkerPosition(@WaterMarkPosition position: Int): WaterMarkEngine {
+        this.position = position
+        return this
+    }
+
+    /**
+     * 设置水印文字距离Bitmap内边距
+     * */
+    fun setTextPadding(textPadding: Float): WaterMarkEngine {
+        this.textPadding = textPadding
+        return this
+    }
+
+    /**
+     * 设置水印图片保存路径
+     * */
+    fun setMarkedSavePath(fileName: String): WaterMarkEngine {
+        this.fileName = fileName
+        return this
+    }
+
+    /**
+     * 设置水印图片回调监听
+     * */
+    fun setOnWaterMarkerAddedListener(addedListener: OnWaterMarkerAddedListener): WaterMarkEngine {
+        this.addedListener = addedListener
+        return this
+    }
+
+    /**
+     * 开始添加水印
+     * */
+    fun start() {
+        addedListener.onStart()
+        //初始化画笔
+        textPaint.color = textColor
+        textPaint.typeface = Typeface.DEFAULT_BOLD
+        textPaint.isDither = true // 获取清晰的图像采样
+        textPaint.isFilterBitmap = true
+        textPaint.textSize = textSize
+        textPaint.getTextBounds(marker, 0, marker.length, textRect)
+
+        //添加水印
+        val bitmapConfig = originalBitmap.config
+        val copyBitmap = originalBitmap.copy(bitmapConfig, true)
+        lifecycleScope.launch(Dispatchers.IO) {
+            val canvas = Canvas(copyBitmap)
+            val bitmapWidth = copyBitmap.width
+            val bitmapHeight = copyBitmap.height
+
+            when (position) {
+                WaterMarkPosition.LEFT_TOP -> {
+                    canvas.drawText(marker, textPadding, textPadding, textPaint)
+                }
+
+                WaterMarkPosition.RIGHT_TOP -> {
+                    canvas.drawText(
+                        marker, bitmapWidth - textRect.width() - textPadding, textPadding, textPaint
+                    )
+                }
+
+                WaterMarkPosition.LEFT_BOTTOM -> {
+                    canvas.drawText(marker, textPadding, bitmapHeight - textPadding, textPaint)
+                }
+
+                WaterMarkPosition.RIGHT_BOTTOM -> {
+                    canvas.drawText(
+                        marker,
+                        bitmapWidth - textRect.width() - textPadding, bitmapHeight - textPadding,
+                        textPaint
+                    )
+                }
+
+                WaterMarkPosition.CENTER -> {
+                    canvas.drawText(
+                        marker,
+                        (bitmapWidth - textRect.width()) / 2f, bitmapHeight / 2f,
+                        textPaint
+                    )
+                }
+            }
+
+            //编码照片是耗时操作，需要在子线程或者协程里面
+            val file = File(fileName)
+            val fileOutputStream = FileOutputStream(file)
+            /**
+             * 第一个参数如果是Bitmap.CompressFormat.PNG,那不管第二个值如何变化，图片大小都不会变化，不支持png图片的压缩
+             * 第二个参数是压缩比重，图片存储在磁盘上的大小会根据这个值变化。值越小存储在磁盘的图片文件越小
+             * */
+            copyBitmap.compress(Bitmap.CompressFormat.JPEG, 75, fileOutputStream)
+            fileOutputStream.flush()
+            fileOutputStream.close()
+
+            withContext(Dispatchers.Main) {
+                addedListener.onMarkAdded(file)
+            }
+        }
+    }
+
+    override fun getLifecycle(): Lifecycle {
+        return registry
+    }
+
+    interface OnWaterMarkerAddedListener {
+        fun onStart()
+
+        fun onMarkAdded(file: File)
+    }
+}