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.AppCompatImageViewclass PaintView @JvmOverloads constructor(context: Context?,attrs: AttributeSet? = null,defStyleAttr: Int = 0
) : AppCompatImageView(context!!, attrs, defStyleAttr) {class DrawPath {var id: Long = 0Lvar path: Path? = nullvar paint: Paint? = nullvar points = ArrayList<PointF>()}private var mPaint: Paint? = nullprivate var mPath: Path? = nullprivate var mDownX = 0fprivate var mDownY = 0fprivate var mTempX = 0fprivate 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.REDprivate val mDrawPathList: ArrayList<DrawPath>?private val mSavePathList: ArrayList<DrawPath>?companion object {var WIDTH_INCREMENT = 15const val TAG = "PaintView"}init {mDrawPathList = ArrayList()mSavePathList = ArrayList()initPaint()}private fun initPaint() {mPaint = Paint()mPaint?.color = mColormPaint?.isAntiAlias = truemPaint?.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.xmDownY = 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 = mPaintdrawPath.path = mPathmDrawPathList?.add(drawPath)//新一轮绘制开始，保存点。drawPath.points.add(PointF(event.x, event.y))invalidate()mTempX = mDownXmTempY = mDownY}MotionEvent.ACTION_MOVE -> {//Log.d(TAG, "ACTION_MOVE ${event.x} ${event.y}")val moveX = event.xval moveY = event.ymPath?.quadTo(mTempX, mTempY, moveX, moveY)mDrawPathList?.filter {it.path == mPath}?.forEach {it.points.add(PointF(event.x, event.y))}invalidate()mTempX = moveXmTempY = 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 = colormPaint?.color = this.mColor}/*** 画笔的宽度。*/fun setPaintWidth(size: Int) {mPaintWidth += sizemPaint?.strokeWidth = mPaintWidth.toFloat()}/*** 放大，改变画笔的宽度。线条变粗。*/fun enlargePaintWidth() {mPaintWidth += WIDTH_INCREMENTmPaint?.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.PaintViewandroid: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" /><RelativeLayoutandroid:id="@+id/rl_left"android:layout_width="100dp"android:layout_height="wrap_content"app:layout_constraintStart_toStartOf="parent"app:layout_constraintTop_toTopOf="parent"><Buttonandroid:id="@+id/btn_undo"android:layout_width="match_parent"android:layout_height="60dp"android:text="撤销" /><Buttonandroid:id="@+id/btn_red"android:layout_width="match_parent"android:layout_height="60dp"android:layout_below="@id/btn_undo"android:text="红色" /><Buttonandroid:id="@+id/btn_green"android:layout_width="match_parent"android:layout_height="60dp"android:layout_below="@id/btn_red"android:text="绿色" /><Buttonandroid: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https://blog.csdn.net/zhangphil/article/details/87810653