多线程编程 1.随便选择两个城市作为预选旅游目标。实现两个独立的线程分别显示10次城市名，每次显示后休眠一段随机时间(1000ms以内)，哪个先显示完毕，就决定去哪个城市。分别用Runnable接口和Thread类实现

<?xml version="1.0" encoding="utf-8"?>
<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"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context="com.hanqi.testapp2.duoxianchengActivity"
    android:orientation="vertical">

    <Button
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="点击选择"
        android:id="@+id/btt_1"
        android:onClick="btt1_OnClick"/>

</LinearLayout>

package com.hanqi.testapp2;

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

import java.util.Random;

public class duoxianchengActivity extends AppCompatActivity {

    Button btt_1;

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

        btt_1=(Button)findViewById(R.id.btt_1);
    }
    Random random=new Random();


        public void btt1_OnClick(View v) {

            for (int i = 0; i < 10; i++) {
                new Thread() {
                    @Override
                    public void run() {
                        try {

                            Thread.sleep(random.nextInt(1000));
                        } catch (Exception e) {

                        }
                        runOnUiThread(new Runnable() {
                            @Override
                            public void run() {

                                btt_1.setText("淄博");
                            }
                        });
                        return;
                    }
                }.start();

                new Thread(new Runnable() {
                    @Override
                    public void run() {
                        try {
                            Thread.sleep(random.nextInt(1000));
                        } catch (Exception e) {

                        }
                        runOnUiThread(new Runnable() {
                            @Override
                            public void run() {

                                btt_1.setText("青岛");
                            }
                        });
                        return;
                    }
                }).start();
            }

          }
        }