Hi everybady hope your are fine
i have a litle problem in my very basic Drawing android app i have an Image Button to change PaintColor but the problem is :the Color is Change for just milisecond then it come back to the basic color witch define in the DrawingView class ,other problem is all the previeus Drawing Lines Change to the newColor and come back to the basic one this is my 2 classes it is very basic project
DrawingView.kt
package com.wissewassim.kid_drawing_app
import android.content.Context
import android.graphics.*
import android.util.AttributeSet
import android.util.TypedValue
import android.view.MotionEvent
import android.view.View
import kotlin.collections.ArrayList
class DrawingView (context : Context, attrs :AttributeSet) : View(context,attrs) {
private var mDrawPath : CustomPath? = null
private var mCanvasBitmap : Bitmap? = null
private var mDrawPaint : Paint? = null
private var mCanvasPaint : Paint? = null
private var mBrishSize : Float = 0.toFloat()
private var color : Int = Color.CYAN
private var canvas : Canvas? = null
private val paths = ArrayList<CustomPath>()
init {
setUpDrawing()
}
private fun setUpDrawing(){
/** we give it to drawPath to draw in the screen */
mDrawPaint = Paint()
/**we use it to draw on the scren using the Paint that returnned from customPath.class */
mDrawPath = CustomPath(color,mBrishSize)
/**define the style and the color and the edges of the line of the draw (attributes) */
mDrawPaint!!.color = color
mDrawPaint!!.style = Paint.Style.STROKE
mDrawPaint!!.strokeCap = Paint.Cap.ROUND
mDrawPaint!!.strokeJoin = Paint.Join.ROUND
/**we use it to draw the canvas on the view with PaintFlag
* PaintFlag: how does this canvas render in the screen*/
mCanvasPaint= Paint(Paint.DITHER_FLAG)
/**the size of the brush we use it to draw lines */
mBrishSize = 20.toFloat()
}
/** put canvas it the view each time the screen size changed
* or an view was added to the hierarchy
* */
override fun onSizeChanged(w: Int, h: Int, oldw: Int, oldh: Int) {
super.onSizeChanged(w, h, oldw, oldh)
mCanvasBitmap = Bitmap.createBitmap(w,h,Bitmap.Config.ARGB_8888)
canvas = Canvas(mCanvasBitmap!!)
}
/**هده الدالى تستدعي عند بدأ الرسم علي canvas*/
override fun onDraw(canvas: Canvas) {
super.onDraw(canvas)
/**
* بقوم بالرسم باستخدام دالة ال canvas نمرر لها ( mCanvasPaint witch has the Attributes of the draw ,الاحداصيات Y;الاحداصيات X,الكنفس التي سنرسم عليها )
*/
canvas.drawBitmap(mCanvasBitmap!!,0f,0f,mCanvasPaint)
//set mDrawPaint stroke and color using the old path colors to draw it again
for (path in paths){
//initialize the stroke width using the object we created from customPath.class
mDrawPaint!!.strokeWidth = path.brishThickness
mDrawPath!!.color = path.color
//
canvas.drawPath(path,mDrawPaint!!)
}
//check if the drawPath was created using the inner class CustomPath
if(!mDrawPath!!.isEmpty){
//initialize the stroke width using the object we created from customPath.class
mDrawPaint!!.strokeWidth = mDrawPath!!.brishThickness
//initialize the draw color using the object we created from customPath.class
mDrawPaint!!.color = mDrawPath!!.color
///pass the drawpath and draw paint to the canvas to draw the path in the method draw path
canvas.drawPath(mDrawPath!!,mDrawPaint!!)
}
}
fun setBrushSize(newSize : Float){
mBrishSize= TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP,newSize,resources.displayMetrics)
mDrawPaint!!.strokeWidth = mBrishSize
mDrawPaint!!.color = color
}
override fun onTouchEvent(event: MotionEvent?): Boolean {
val touchX = event?.x
val touchY = event?.y
when (event?.action) {
MotionEvent.ACTION_DOWN -> {
mDrawPath!!.color = color
mDrawPath!!.brishThickness = mBrishSize
mDrawPath!!.reset()
if (touchY != null) {
if (touchX != null) {
mDrawPath!!.moveTo(touchX, touchY)
}
}
}
MotionEvent.ACTION_MOVE -> {
if (touchY != null) {
if (touchX != null) {
mDrawPath!!.lineTo(touchX, touchY)
}
}
}
MotionEvent.ACTION_UP -> {
paths.add(mDrawPath!!)
mDrawPath = CustomPath(color, mBrishSize )
}
else -> return false
}
invalidate()
return true
}
fun setpathColor(newColor : Int ){
color = newColor
mDrawPaint!!.color= color
}
/** inner class to create customPath that we use to draw using it */
internal class CustomPath(var color:Int, var brishThickness : Float ): Path()
}
MainActivity.kt
package com.wissewassim.kid_drawing_app
import android.app.Dialog
import android.graphics.Color
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.view.View
import android.view.View.OnClickListener
import android.widget.ImageButton
import com.wissewassim.kid_drawing_app.databinding.ActivityMainBinding
class MainActivity : AppCompatActivity(), OnClickListener {
private lateinit var binding: ActivityMainBinding
private var brushSize = 0.toFloat()
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
binding = ActivityMainBinding.inflate(layoutInflater)
val view = binding.root
setContentView(view)
//set the default brush size
binding.drawingView.setBrushSize(20.toFloat())
//change brush size when choose size in choosing brush size Dialog
binding.ibBrushSizeChange.setOnClickListener{ brushSizeDialog() }
binding.ibBrushColorRed.setOnClickListener(brushSizeDialog())
binding.ibBrushColorGreen.setOnClickListener(brushSizeDialog())
binding.ibBrushColorBlack.setOnClickListener(brushSizeDialog())
binding.ibBrushColorBlue.setOnClickListener(brushSizeDialog())
binding.ibBrushColorYellow.setOnClickListener(brushSizeDialog())
}
private fun brushSizeDialog(){
val brushDialog = Dialog(this)
brushDialog.setContentView(R.layout.dialog_brush_size)
brushDialog.setTitle("set brush size :")
val smallbrush = brushDialog.findViewById<ImageButton>(R.id.ib_small_brush_size)
val mudiumbrush = brushDialog.findViewById<ImageButton>(R.id.ib_meduim_brush_size)
val largebrush = brushDialog.findViewById<ImageButton>(R.id.ib_large_brush_size)
smallbrush.setOnClickListener{
brushSize = 20.toFloat()
binding.drawingView.setBrushSize(brushSize)
brushDialog.dismiss()
}
mudiumbrush.setOnClickListener{
brushSize = 30.toFloat()
binding.drawingView.setBrushSize(brushSize)
brushDialog.dismiss()
}
largebrush.setOnClickListener{
brushSize = 40.toFloat()
binding.drawingView.setBrushSize(brushSize)
brushDialog.dismiss()
}
brushDialog.show()
}
override fun onClick(v: View?) {
when(v?.id){
binding.ibBrushColorRed.id->{
binding.drawingView.setpathColor(Color.RED)
}
binding.ibBrushColorBlack.id->{
binding.drawingView.setpathColor(Color.BLACK)
}
binding.ibBrushColorYellow.id->{
binding.drawingView.setpathColor(Color.YELLOW)
}
binding.ibBrushColorGreen.id->{
binding.drawingView.setpathColor(Color.GREEN)
}
binding.ibBrushColorBlue.id->{
binding.drawingView.setpathColor(Color.BLUE)
}
}
}
}
Change your
DrawingViewclass with this :