从零开始学android<android基本绘图.四十六.>

<span style="font-size:18px;"><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    
    tools:context=".MainActivity" >

    <com.example.paintpic.MyView
        android:id="@+id/Myview"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
></com.example.paintpic.MyView>
</LinearLayout>
</span>

<span style="font-size:18px;">package com.example.paintpic;

import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;

public class MainActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }


    
}
</span>

<span style="font-size:18px;">package com.example.paintpic;

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.RectF;
import android.util.AttributeSet;
import android.view.View;

public class MyView extends View {

	public MyView(Context context, AttributeSet attrs) {
		super(context, attrs);
		// TODO Auto-generated constructor stub
	}

	@Override
	protected void onDraw(Canvas canvas) {
		// TODO Auto-generated method stub
		// canvas是画板对象，背景是白色的
		canvas.drawColor(Color.WHITE);
		// paint画笔工具
		Paint paint = new Paint();
		// 设置画笔颜色为蓝色
		paint.setColor(Color.BLUE);
		// 为画板上画圆，圆心（50,50）半径50
		canvas.drawCircle(50, 50, 50, paint);
		// 设置画笔颜色的颜色为红色
		paint.setColor(Color.RED);
		// 画矩形
		canvas.drawRect(100, 0, 160, 80, paint);
		// 画笔颜色为绿色
		paint.setColor(Color.GREEN);
		// 画直线
		canvas.drawLine(50, 110, 200, 110, paint);
		paint.setColor(Color.YELLOW);
		// Rect rect=new Rect(120, 120, 300, 300);
		// canvas.drawRect(rect, paint);

		// 使用RectF画多边形
		RectF oval = new RectF();
		oval.set(10.0f, 140.0f, 110.0f, 200.0f);
		canvas.drawOval(oval, paint);

		oval = new RectF();
		oval.set(150.0f, 140.0f, 210.0f, 200.0f);
		canvas.drawArc(oval, 150.0f, 140.0f, true, paint);
	}
}
</span>