[Android] CustomView 추가 실습

아래 그림과 같이 도형을 선택하는 라디오 버튼을 만들고, 선택한 도형에 따라 터치할 때 그린다.

 

activity_main.xml

<?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">

    <view
        android:id="@+id/view"
        class="com.example.myapplication.MyView"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_weight="1"
        app:layout_constraintBottom_toTopOf="@+id/radioGp"
        app:layout_constraintTop_toTopOf="parent"
        tools:layout_editor_absoluteX="8dp" />

    <RadioGroup
        android:id="@+id/radioGp"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:orientation="horizontal"
        app:layout_constraintBottom_toBottomOf="parent">

        <RadioButton
            android:id="@+id/radio_Rectangle"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginStart="8dp"
            android:layout_marginEnd="150dp"
            android:checked="true"
            android:text="@string/rectangle" />

        <RadioButton
            android:id="@+id/radio_Circle"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@string/circle" />
    </RadioGroup>


</androidx.constraintlayout.widget.ConstraintLayout>

 

MainActivity

import android.os.Bundle
import androidx.appcompat.app.AppCompatActivity
import com.example.myapplication.databinding.ActivityMainBinding

class MainActivity() : AppCompatActivity() {
    lateinit var binding: ActivityMainBinding

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        binding = ActivityMainBinding.inflate(layoutInflater)
        setContentView(binding.root)

        binding.radioGp.setOnCheckedChangeListener { _, checkedId ->
            when (checkedId) {
                R.id.radio_Circle -> binding.view.setFigure("circle")
                R.id.radio_Rectangle -> binding.view.setFigure("rect")
            }
        }
    }
}

 

MyView

import android.annotation.SuppressLint
import android.content.Context
import android.graphics.*
import android.util.AttributeSet
import android.view.MotionEvent
import android.view.View

class MyView : View {
    private var rect = Rect(10, 10, 110, 110)
    private var circleX = 100F
    private var circleY = 100F
    private var circleR = 50F

    private var color = Color.BLUE
    private val paint = Paint()

    constructor(context: Context) : super(context)
    constructor(context: Context, attrs: AttributeSet) : super(context, attrs)

    private var newFigure: String = "rect"

    fun setFigure(figure: String) {
        newFigure = figure
    }

    override fun onDraw(canvas: Canvas) {
        super.onDraw(canvas)

        paint.color = color

        when (newFigure) {
            "circle" -> canvas.drawCircle(circleX, circleY, circleR, paint)
            "rect" -> canvas.drawRect(rect, paint)
        }
    }

    @SuppressLint("ClickableViewAccessibility")
    override fun onTouchEvent(event: MotionEvent): Boolean {
        if (event.action == MotionEvent.ACTION_DOWN ||
            event.action == MotionEvent.ACTION_MOVE
        ) {
            rect.left = event.x.toInt()
            rect.top = event.y.toInt()
            rect.right = rect.left + 100
            rect.bottom = rect.top + 100

            circleX = event.x
            circleY = event.y

            invalidate()
            return true
        }
        return super.onTouchEvent(event)
    }
}

간단한 추가실습이었다.