自定义布局代码：

package com.example.workday06;

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 Demo1 extends View {
    private Paint paint;
    private Paint paint1;
    private Paint paint2;
    private Paint paint3;

    public Demo1(Context context, AttributeSet attrs) {
        super(context, attrs);
        initView();
    }

    private void initView() {
        paint = new Paint();
        paint1 = new Paint();
        paint2 = new Paint();
        paint3 = new Paint();
        //设置画笔属性
        paint.setStyle(Paint.Style.FILL_AND_STROKE);
        paint.setStrokeWidth(2);
        paint.setAntiAlias(true);
        paint.setColor(Color.RED);

        paint1.setStyle(Paint.Style.FILL_AND_STROKE);
        paint1.setStrokeWidth(2);
        paint1.setAntiAlias(true);
        paint1.setColor(Color.YELLOW);

        paint2.setStyle(Paint.Style.FILL_AND_STROKE);
        paint2.setStrokeWidth(2);
        paint2.setAntiAlias(true);
        paint2.setColor(Color.BLUE);

        paint3.setStyle(Paint.Style.FILL_AND_STROKE);
        paint3.setStrokeWidth(2);
        paint3.setAntiAlias(true);
        paint3.setColor(Color.GREEN);
    }

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        //画圆柱
        canvas.drawOval(100,100,400,200,paint);
        canvas.drawLine(100,150,100,600,paint);
        canvas.drawLine(400,150,400,600,paint);
        canvas.drawOval(100,550,400,650,paint);

        //画饼
        RectF rectF1 = new RectF(500,400,900,800);
        canvas.drawArc(rectF1,0,90,true,paint);
        canvas.drawArc(rectF1,90,90,true,paint1);
        canvas.drawArc(rectF1,180,90,true,paint2);
        canvas.drawArc(rectF1,270,90,true,paint3);


    }
}

主类代码：

package com.example.workday06;

import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;

public class workday06 extends AppCompatActivity {
    Button button;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_workday06);
        Demo1 demo1 = findViewById(R.id.demo1);
        button = findViewById(R.id.clock);
    }
}

效果图：