Android图片涂鸦，Kotlin（1）

柔光的暖阳◎ 2024-02-18 11:45 41阅读 0赞

### Android图片涂鸦，Kotlin（1） ###

###  ###

import android.content.Context
    import android.graphics.Canvas
    import android.graphics.Color
    import android.graphics.Paint
    import android.graphics.Path
    import android.graphics.PointF
    import android.util.AttributeSet
    import android.util.Log
    import android.view.MotionEvent
    import androidx.appcompat.widget.AppCompatImageView
    
    
    class PaintView @JvmOverloads constructor(
        context: Context?,
        attrs: AttributeSet? = null,
        defStyleAttr: Int = 0
    ) : AppCompatImageView(context!!, attrs, defStyleAttr) {
    
        class DrawPath {
            var id: Long = 0L
    
            var path: Path? = null
            var paint: Paint? = null
            var points = ArrayList<PointF>()
        }
    
        private var mPaint: Paint? = null
        private var mPath: Path? = null
    
        private var mDownX = 0f
        private var mDownY = 0f
        private var mTempX = 0f
        private var mTempY = 0f
    
        //默认的画笔宽度
        private var mPaintWidth = 10
    
        //默认画笔的颜色
        private var mColor = Color.RED
    
        private val mDrawPathList: ArrayList<DrawPath>?
        private val mSavePathList: ArrayList<DrawPath>?
    
        companion object {
            var WIDTH_INCREMENT = 15
            const val TAG = "PaintView"
        }
    
        init {
            mDrawPathList = ArrayList()
            mSavePathList = ArrayList()
            initPaint()
        }
    
        private fun initPaint() {
            mPaint = Paint()
    
            mPaint?.color = mColor
            mPaint?.isAntiAlias = true
            mPaint?.strokeWidth = mPaintWidth.toFloat()
            mPaint?.style = Paint.Style.STROKE
        }
    
        override fun onDraw(canvas: Canvas) {
            super.onDraw(canvas)
    
            if (!mDrawPathList.isNullOrEmpty()) {
                for (drawPath in mDrawPathList) {
                    if (drawPath.path != null) {
                        canvas.drawPath(drawPath.path!!, drawPath.paint!!)
                    }
    
                    drawPath.points.forEach {
                        Log.d(TAG, "onDraw ${drawPath.id} ${it.x} ${it.y}")
                    }
                }
            }
        }
    
        override fun onTouchEvent(event: MotionEvent): Boolean {
            when (event.action) {
                MotionEvent.ACTION_DOWN -> {
                    Log.d(TAG, "ACTION_DOWN ${event.x} ${event.y}")
    
                    mDownX = event.x
                    mDownY = event.y
    
                    //每次手指点下去作为一条新路径。
                    mPath = Path()
                    mPath?.moveTo(mDownX, mDownY)
    
                    val drawPath = DrawPath()
                    drawPath.id = System.currentTimeMillis()
                    drawPath.paint = mPaint
                    drawPath.path = mPath
                    mDrawPathList?.add(drawPath)
    
                    //新一轮绘制开始，保存点。
                    drawPath.points.add(PointF(event.x, event.y))
    
                    invalidate()
                    mTempX = mDownX
                    mTempY = mDownY
                }
    
                MotionEvent.ACTION_MOVE -> {
                    //Log.d(TAG, "ACTION_MOVE ${event.x} ${event.y}")
    
                    val moveX = event.x
                    val moveY = event.y
    
                    mPath?.quadTo(mTempX, mTempY, moveX, moveY)
    
                    mDrawPathList?.filter {
                        it.path == mPath
                    }?.forEach {
                        it.points.add(PointF(event.x, event.y))
                    }
    
                    invalidate()
                    mTempX = moveX
                    mTempY = moveY
                }
    
                //每次手指抬起重置画笔,不然画笔会保存之前设置的属性会引起bug。
                MotionEvent.ACTION_UP -> {
                    Log.d(TAG, "ACTION_UP ${event.x} ${event.y}")
                    initPaint()
                }
            }
    
            return true
        }
    
        /**
         * 撤销。
         */
        fun undo() {
            if (mDrawPathList != null && mDrawPathList.size >= 1) {
                mSavePathList?.add(mDrawPathList[mDrawPathList.size - 1])
                mDrawPathList.removeAt(mDrawPathList.size - 1)
    
                invalidate()
            }
        }
    
        /**
         * 反撤销，重新生效。
         */
        fun reundo() {
            if (!mSavePathList.isNullOrEmpty()) {
                mDrawPathList?.add(mSavePathList[mSavePathList.size - 1])
                mSavePathList.removeAt(mSavePathList.size - 1)
    
                invalidate()
            }
        }
    
        /**
         * 画笔颜色。
         *
         * @param color
         */
        fun setPaintColor(color: Int) {
            this.mColor = color
            mPaint?.color = this.mColor
        }
    
        /**
         * 画笔的宽度。
         */
        fun setPaintWidth(size: Int) {
            mPaintWidth += size
            mPaint?.strokeWidth = mPaintWidth.toFloat()
        }
    
        /**
         * 放大，改变画笔的宽度。线条变粗。
         */
        fun enlargePaintWidth() {
            mPaintWidth += WIDTH_INCREMENT
            mPaint?.strokeWidth = mPaintWidth.toFloat()
        }
    
        fun getDrawPath(): ArrayList<DrawPath>? {
            return mDrawPathList
        }
    }

<?xml version="1.0" encoding="utf-8"?>
    <androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:app="http://schemas.android.com/apk/res-auto"
        xmlns:tools="http://schemas.android.com/tools"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        tools:context=".MainActivity">
    
        <com.pkg1115.PaintView
            android:id="@+id/paint_view"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:scaleType="fitCenter"
            android:src="@mipmap/p1"
            app:layout_constraintBottom_toBottomOf="parent"
            app:layout_constraintEnd_toEndOf="parent"
            app:layout_constraintStart_toStartOf="parent"
            app:layout_constraintTop_toTopOf="parent" />
    
        <RelativeLayout
            android:id="@+id/rl_left"
            android:layout_width="100dp"
            android:layout_height="wrap_content"
            app:layout_constraintStart_toStartOf="parent"
            app:layout_constraintTop_toTopOf="parent">
    
            <Button
                android:id="@+id/btn_undo"
                android:layout_width="match_parent"
                android:layout_height="60dp"
                android:text="撤销" />
    
            <Button
                android:id="@+id/btn_red"
                android:layout_width="match_parent"
                android:layout_height="60dp"
                android:layout_below="@id/btn_undo"
                android:text="红色" />
    
            <Button
                android:id="@+id/btn_green"
                android:layout_width="match_parent"
                android:layout_height="60dp"
                android:layout_below="@id/btn_red"
                android:text="绿色" />
    
            <Button
                android:id="@+id/btn_enlarge"
                android:layout_width="match_parent"
                android:layout_height="60dp"
                android:layout_below="@id/btn_green"
                android:text="放大" />
        </RelativeLayout>
    
    </androidx.constraintlayout.widget.ConstraintLayout>

[Android图形图像处理：添加涂鸦文字\_android 在图片上涂鸦-CSDN博客文章浏览阅读2k次。先看运行效果： 关键的PaintView:package com.zhangphil;import android.content.Context;import android.graphics.Canvas;import android.graphics.Color;import android.graphics.Paint;import android.graph...\_android 在图片上涂鸦![favicon32.ico][]https://blog.csdn.net/zhangphil/article/details/87810653][Android_android _-CSDN_2k_ _PaintView_package com.zhangphil_import android.content.Context_import android.graphics.Canvas_import android.graphics.Color_import android.graphics.Paint_import android.graph..._android _favicon32.ico_https_blog.csdn.net_zhangphil_article_details_87810653]

[favicon32.ico]: https://image.dandelioncloud.cn/pgy_files/images/2024/02/18/01f68dced0b84470a7f424dc0a6a7d44.png
[Android_android _-CSDN_2k_ _PaintView_package com.zhangphil_import android.content.Context_import android.graphics.Canvas_import android.graphics.Color_import android.graphics.Paint_import android.graph..._android _favicon32.ico_https_blog.csdn.net_zhangphil_article_details_87810653]: https://blog.csdn.net/zhangphil/article/details/87810653