[Android] AlertDialog获取网上天气并显示各城市天气

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >

    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="50dp"
        android:background="#484E61" >
        <Button
            android:id="@+id/close_weather"
            android:layout_width="30dp"
            android:layout_height="30dp"
            android:layout_centerVertical="true"
            android:layout_marginLeft="10dp"
            android:background="@drawable/home" />
        <TextView
            android:id="@+id/city_name"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_centerInParent="true"
            android:textColor="#fff"
            android:textSize="24sp" />
        <Button
            android:id="@+id/refresh_weather"
            android:layout_width="30dp"
            android:layout_height="30dp"
            android:layout_alignParentRight="true"
            android:layout_centerVertical="true"
            android:layout_marginRight="10dp"
            android:background="@drawable/refresh" />
    </RelativeLayout>

    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_weight="1"
        android:background="#27A5F9" >
        <TextView
            android:id="@+id/publish_text"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentRight="true"
            android:layout_marginRight="10dp"
            android:layout_marginTop="10dp"
            android:textColor="#FFF"
            android:textSize="18sp" />
        <LinearLayout
            android:id="@+id/weather_info_layout"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_centerInParent="true"
            android:orientation="vertical" >
            <TextView
                android:id="@+id/current_date"
                android:layout_width="wrap_content"
                android:layout_height="40dp"
                android:gravity="center"
                android:textColor="#FFF"
                android:textSize="18sp" />
            <TextView
                android:id="@+id/weather_desp"
                android:layout_width="wrap_content"
                android:layout_height="60dp"
                android:layout_gravity="center_horizontal"
                android:gravity="center"
                android:textColor="#FFF"
                android:textSize="40sp" />
            <LinearLayout
                android:layout_width="wrap_content"
                android:layout_height="60dp"
                android:layout_gravity="center_horizontal"
                android:orientation="horizontal" >
                <TextView
                    android:id="@+id/temp1"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_gravity="center_vertical"
                    android:textColor="#FFF"
                    android:textSize="40sp" />
                <TextView
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_gravity="center_vertical"
                    android:layout_marginLeft="10dp"
                    android:layout_marginRight="10dp"
                    android:text="~"
                    android:textColor="#FFF"
                    android:textSize="40sp" />
                <TextView
                    android:id="@+id/temp2"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_gravity="center_vertical"
                    android:textColor="#FFF"
                    android:textSize="40sp" />
            </LinearLayout>
        </LinearLayout>
    </RelativeLayout>

</LinearLayout>

public class MainActivity extends Activity implements OnClickListener {

	//自定义变量
	private TextView cityNameText;       //用于显示城市名
	private TextView publishText;        //用于显示发布时间
	private TextView weatherDespText;    //用于显示天气描述信息
	private TextView temp1Text;          //用于显示最低气温
	private TextView temp2Text;          //用于显示最高气温
	private TextView currentDateText;    //用于显示当前日期
	private Button closeWeather;         //退出程序
	private Button refreshWeather;       //更新天气按钮
	private String weatherCode;          //天气代码
	private String weatherJson;          //获取JSON格式
	
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        requestWindowFeature(Window.FEATURE_NO_TITLE);
        setContentView(R.layout.activity_main);
        
        //获取对象
        cityNameText = (TextView) findViewById(R.id.city_name);
		publishText = (TextView) findViewById(R.id.publish_text);
		weatherDespText = (TextView) findViewById(R.id.weather_desp);
		temp1Text = (TextView) findViewById(R.id.temp1);
		temp2Text = (TextView) findViewById(R.id.temp2);
		currentDateText = (TextView) findViewById(R.id.current_date);
		closeWeather = (Button) findViewById(R.id.close_weather);
		refreshWeather = (Button) findViewById(R.id.refresh_weather);
		
        //主活动 implements OnClickListener
		closeWeather.setOnClickListener(this);
		refreshWeather.setOnClickListener(this);
    }
    
    @Override
	public void onClick(View v) {
		switch (v.getId()) {
		case R.id.close_weather:
			finish();
			break;
		case R.id.refresh_weather:
			DialogChooseCity();
			break;
		default:
			break;
		}
	}
    
    /**
     * 自定义对话框 获取城市
     * 中国天气网 
     * http://www.weather.com.cn/data/cityinfo/101010100.html
     */
  	private void DialogChooseCity() {
  		//创建对话框
  		AlertDialog.Builder  builder = new AlertDialog.Builder(MainActivity.this);
  		builder.setTitle("请选择一个城市");
  		builder.setIcon(android.R.drawable.ic_dialog_info);
  		//指定下拉列表的显示数据
  		final String[] cities = {"北京", "上海", "天津", "广州", "贵阳", "台北", "香港"};
  		final String[] codes = {"101010100", "101020100", "101030100","101280101",
  				"101260101", "101340101", "101320101"};
  		builder.setItems(cities, new DialogInterface.OnClickListener()
        {
            @Override
            public void onClick(DialogInterface dialog, int which)
            {
            	weatherCode = codes[which];
            	//执行线程访问http
            	//否则 NetworkOnMainThreadException
            	new Thread(new Runnable() {
        			@Override
        			public void run() {
		            	
		            	//访问中国天气网
		            	String weatherUrl = "http://www.weather.com.cn/data/cityinfo/"
								+ weatherCode + ".html";
						weatherJson = queryStringForGet(weatherUrl);
						//JSON格式解析
						try {
							JSONObject jsonObject = new JSONObject(weatherJson);
							JSONObject weatherObject = jsonObject
									.getJSONObject("weatherinfo");
							Message message = new Message();
							message.obj = weatherObject;
							handler.sendMessage(message);
						} catch (JSONException e) {
							// TODO Auto-generated catch block
							e.printStackTrace();
						}
        			}
            	}).start();
            }
        });
  		builder.show();
  	}
	
	/**
	 * 解析Json格式数据并显示
	 */
	@SuppressLint("HandlerLeak")
	Handler handler = new Handler() 
	{
		@Override
		public void handleMessage(Message msg) {
			// TODO Auto-generated method stub
			super.handleMessage(msg);
			JSONObject object = (JSONObject) msg.obj;
			try {
				cityNameText.setText(object.getString("city"));
				temp1Text.setText(object.getString("temp1"));
				temp2Text.setText(object.getString("temp2"));
				weatherDespText.setText(object.getString("weather"));
				publishText.setText("今天"+object.getString("ptime")+"发布");
				//获取当前日期
				SimpleDateFormat sdf = new SimpleDateFormat("yyyy年M月d日", Locale.CHINA);
				currentDateText.setText(sdf.format(new Date()));
			} catch (Exception e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
		}
	};
	
	/**
	 * 网络查询
	 */
	private String queryStringForGet(String url) {
		HttpGet request = new HttpGet(url);
		String result = null;
		try {
			HttpResponse response = new DefaultHttpClient().execute(request);
			if (response.getStatusLine().getStatusCode() == 200) {
				result = EntityUtils.toString(response.getEntity(), HTTP.UTF_8);
				return result;
			}
		} catch (ClientProtocolException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (ParseException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		return result;
	}

}

<!-- 申请权限 -->
<uses-permission android:name="android.permission.INTERNET" />

 new Thread(new Runnable() {
        @Override
        public void run() {
            //具体操作
            ....
        }
    }).start();

   (4)学会自定义AlertDialog并调用它,同时获取网络图片那个URL当时查看到没记录,可惜了.
    PS:最后推荐看看郭神《Android第一行代码》第十四章关于天气的讲解,但基本原理和方法该文章我都已经讲述了.

public static String getWeather(String city){   
	String result=null;
	String url="http://php.weather.sina.com.cn/iframe/index/w_cl.php?code=js&day=2&city="+city+"&dfc=3";
    try{   
    	DefaultHttpClient client = getDefaultHttpClient2();   
    	HttpGet mothod = new HttpGet(url);   
    	HttpResponse httpResponse = client.execute(mothod);
		if (httpResponse.getStatusLine().getStatusCode() == 200)  
         {  
              result = EntityUtils.toString(httpResponse.getEntity(),"gb2312");  
         }  
    }catch(Exception ex){   
        ex.printStackTrace();   
    }   
    return result;   
}  

private int imageResoId(String weather){
	int resoid=R.drawable.s_2;
	if(weather.indexOf("多云")!=-1||weather.indexOf("晴")!=-1){//多云转晴，以下类同 indexOf:包含字串
        resoid=R.drawable.s_1;}
    else if(weather.indexOf("多云")!=-1&&weather.indexOf("阴")!=-1){
        resoid=R.drawable.s_2;}
    else if(weather.indexOf("阴")!=-1&&weather.indexOf("雨")!=-1){
        resoid=R.drawable.s_3;}
    else if(weather.indexOf("晴")!=-1&&weather.indexOf("雨")!=-1){
        resoid=R.drawable.s_12;}
    else if(weather.indexOf("晴")!=-1&&weather.indexOf("雾")!=-1){
        resoid=R.drawable.s_12;}
    else if(weather.indexOf("晴")!=-1){resoid=R.drawable.s_13;}
    else if(weather.indexOf("多云")!=-1){resoid=R.drawable.s_2;}
    else if(weather.indexOf("阵雨")!=-1){resoid=R.drawable.s_3;}
    else if(weather.indexOf("小雨")!=-1){resoid=R.drawable.s_3;}
    else if(weather.indexOf("中雨")!=-1){resoid=R.drawable.s_4;}
    else if(weather.indexOf("大雨")!=-1){resoid=R.drawable.s_5;}
    else if(weather.indexOf("暴雨")!=-1){resoid=R.drawable.s_5;}
    else if(weather.indexOf("冰雹")!=-1){resoid=R.drawable.s_6;}
    else if(weather.indexOf("雷阵雨")!=-1){resoid=R.drawable.s_7;}
    else if(weather.indexOf("小雪")!=-1){resoid=R.drawable.s_8;}
    else if(weather.indexOf("中雪")!=-1){resoid=R.drawable.s_9;}
    else if(weather.indexOf("大雪")!=-1){resoid=R.drawable.s_10;}
    else if(weather.indexOf("暴雪")!=-1){resoid=R.drawable.s_10;}
    else if(weather.indexOf("扬沙")!=-1){resoid=R.drawable.s_11;}
    else if(weather.indexOf("沙尘")!=-1){resoid=R.drawable.s_11;}
    else if(weather.indexOf("雾")!=-1){resoid=R.drawable.s_12;}
	return resoid;
}

//输入城市名
private void showOtherCity() {
	LayoutInflater inflater = getLayoutInflater();
	View layout = inflater.inflate(R.layout.weather_other_city,(ViewGroup) findViewById(R.id.ws_dialog));
	dialogCity = (EditText)layout.findViewById(R.id.ws_city_name);
	//创建对话框
    new AlertDialog.Builder(this).setTitle("请输入城市名称").setView(layout)
    	.setPositiveButton("确定",new DialogInterface.OnClickListener() {
		     public void onClick(DialogInterface dialog, int id) {
		    	 cityName = dialogCity.getText().toString();
		    	 Intent intent = new Intent(MainActivity.this, WeatherScreen.class);
		    	 intent.putExtra("extra_data", cityName);
		    	 startActivity(intent);
		       }
    	})
	 .setNegativeButton("取消", new DialogInterface.OnClickListener() {
	     public void onClick(DialogInterface dialog, int id) {
	    	   dialog.cancel();
	       }
	   }).show();
}