利用CountDownTimer倒计时的简单使用实现

package com.loaderman.countdowntimerdemo;

import android.os.Bundle;
import android.os.CountDownTimer;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity {

    private TextView tvTime;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        tvTime = (TextView) findViewById(R.id.tv_time);
        tvTime.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                new countDownTimer<TextView>(tvTime);
            }
        });
    }
    public class countDownTimer<T> extends CountDownTimer {
        private TextView mTextView;

        public countDownTimer(T text) {
            super(60000,1000);
            this.mTextView = ((TextView)text);
            mTextView.setClickable(false);
            start();
        }

        /**
         * start后开始执行的方法，按照间隔时间执行一次
         * @param millisUntilFinished
         */
        @Override
        public void onTick(long millisUntilFinished) {
            mTextView.setText(String.format("%s秒",millisUntilFinished/1000));
        }

        /**
         *  时间结束时调用的方法
         */
        @Override
        public void onFinish() {
            mTextView.setText("获取验证码");
            mTextView.setClickable(true);
        }
    }
}

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/activity_main"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:gravity="center"
    tools:context="com.loaderman.countdowntimerdemo.MainActivity">
    <TextView
        android:textColor="#F00"
        android:textSize="18sp"
        android:id="@+id/tv_time"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="开始倒计时"/>
</RelativeLayout>

效果图: