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1.使用 http://int.dpool.sina.com.cn/iplookup/iplookup.PHP?format=json 新浪 IP API 进行城市定位。

2.添加 ProgressDialog ，获取数据时显示“请稍后”。
报错：java.lang.RuntimeException: Can't create handler inside thread that has not called Looper.prepare()
UI组件不能写在进程中，要写在handle中，通过进程发消息控制其显隐。
3.TextView添加点击刷新：
设置TextView的XML的属性 android:onClick="click"，
代码中写：
public void click(View v) {
Toast.makeText(getApplicationContext(),"刷新",Toast.LENGTH_LONG).show();
new Thread(t).start();
}
点击没反应？布局XML文件中要设置TextView的clickable属性值为true,或者对TextView实例调用setClickable方法，参数设为true。

已知问题：刷新后界面乱了：
package com.hy.weatherjhm; import java.io.UnsupportedEncodingException; import java.util.Calendar; import org.json.JSONException; import org.json.JSONObject; import android.app.Activity; import android.app.AlertDialog; import android.app.ProgressDialog; import android.os.Bundle; import android.os.Handler; import android.os.Message; import android.view.Gravity; import android.view.Menu; import android.view.MenuItem; import android.view.View; import android.view.ViewGroup.LayoutParams; import android.widget.ImageView; import android.widget.LinearLayout; import android.widget.TextView; import android.widget.Toast; public class MainActivity extends Activity { int iweather[]; String city,url,jsons,tempnow,scity,supdatetime,stempnow,sweather1,stemp1,swind1,shumidity,stoday,sdate[],sweek[],sweather[],stemp[],swind[]; JSONObject jsono,info; private final Handler handler = new Handler(); ProgressDialog PD; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); new Thread(t).start(); } final Runnable mUpdateResults = new Runnable() { @Override public void run() { TextView tvcity = (TextView) findViewById(R.id.city); tvcity.setText(scity); TextView updatetime = (TextView) findViewById(R.id.updatetime); updatetime.setText(supdatetime); TextView tempnow = (TextView) findViewById(R.id.tempnow); tempnow.setText(stempnow); TextView weather0 = (TextView) findViewById(R.id.weather); weather0.setText(sweather[0]); ImageView bg = (ImageView) findViewById(R.id.bg); bg.setImageDrawable(MainActivity.this.getResources().getDrawable( getBgImage(sweather[0]))); TextView temp0 = (TextView) findViewById(R.id.temp); temp0.setText(stemp[0]); TextView wind0 = (TextView) findViewById(R.id.wind); wind0.setText(swind[0]); TextView humidity = (TextView) findViewById(R.id.humidity); humidity.setText(shumidity); TextView today = (TextView) findViewById(R.id.today); today.setText(stoday); LinearLayout future = (LinearLayout) findViewById(R.id.future); for (int i = 1; i < 7; i++) { LinearLayout f = new LinearLayout(MainActivity.this); f.setOrientation(LinearLayout.VERTICAL); f.setGravity(Gravity.CENTER); int p = 0; f.setPadding(p,p,p); future.addView(f,new LinearLayout.LayoutParams( LayoutParams.WRAP_CONTENT,LayoutParams.WRAP_CONTENT)); TextView date = new TextView(MainActivity.this); date.setText(sdate[i]); f.addView(date); date.setGravity(Gravity.CENTER); TextView week = new TextView(MainActivity.this); week.setText(sweek[i]); f.addView(week); week.setGravity(Gravity.CENTER); ImageView wi = new ImageView(MainActivity.this); wi.setImageDrawable(MainActivity.this.getResources() .getDrawable(iweather[i])); f.addView(wi); LayoutParams params = wi.getLayoutParams(); params.width = 90; params.height = 90; wi.setLayoutParams(params); TextView weather = new TextView(MainActivity.this); weather.setText(sweather[i]); f.addView(weather); weather.setGravity(Gravity.CENTER); TextView temp = new TextView(MainActivity.this); temp.setText(stemp[i]); // temp.setLayoutParams(new LayoutParams( // LayoutParams.WRAP_CONTENT,LayoutParams.WRAP_CONTENT)); temp.setGravity(Gravity.CENTER); f.addView(temp); TextView wind = new TextView(MainActivity.this); wind.setText(swind[i]); // wind.setLayoutParams(new LayoutParams( // LayoutParams.WRAP_CONTENT,LayoutParams.WRAP_CONTENT)); wind.setGravity(Gravity.CENTER); f.addView(wind); } PDD.sendEmptyMessage(0); } }; Thread t = new Thread() { @Override public void run() { PDS.sendEmptyMessage(0); url = "http://int.dpool.sina.com.cn/iplookup/iplookup.PHP?format=json"; jsons = HttpUtils.getURLResponse(url); try { jsono = new JSONObject(jsons); city = jsono.getString("city"); } catch (JSONException e1) { // TODO Auto-generated catch block e1.printStackTrace(); } try { city = java.net.URLEncoder.encode(city,"UTF-8"); } catch (UnsupportedEncodingException e) { // TODO Auto-generated catch block e.printStackTrace(); } url = "http://v.juhe.cn/weather/index?cityname=" + city + "&key=e73ad3113b4e8dc2b7e8d8298a40d8e3"; jsons = HttpUtils.getURLResponse(url); try { jsono = new JSONObject(jsons); JSONObject sk = jsono.getJSONObject("result").getJSONObject( "sk"); scity = jsono.getJSONObject("result").getJSONObject("today") .getString("city"); supdatetime = sk.getString("time") + "更新"; stempnow = sk.getString("temp") + "℃"; shumidity = sk.getString("humidity"); stoday = jsono.getJSONObject("result").getJSONObject("today") .getString("date_y") + " " + jsono.getJSONObject("result").getJSONObject("today") .getString("week"); Calendar c = Calendar.getInstance(); String day[] = new String[7]; sdate = new String[7]; sweek = new String[7]; iweather = new int[7]; sweather = new String[7]; stemp = new String[7]; swind = new String[7]; for (int i = 0; i < 7; i++) { int y = c.get(Calendar.YEAR); int m = c.get(Calendar.MONTH) + 1; int d = c.get(Calendar.DAY_OF_MONTH); day[i] = new String("day_" + y + m1(m) + d1(d)); JSONObject day_ = jsono.getJSONObject("result") .getJSONObject("future").getJSONObject(day[i]); sdate[i] = day_.getString("date").substring(4,8); sweek[i] = day_.getString("week"); iweather[i] = getWeatherImage(day_.getString("weather")); sweather[i] = day_.getString("weather"); stemp[i] = day_.getString("temperature"); swind[i] = day_.getString("wind"); c.add(Calendar.DAY_OF_MONTH,1); } } catch (JSONException e) { // TODO Auto-generated catch block e.printStackTrace(); } handler.post(mUpdateResults); } }; @Override public boolean onCreateOptionsMenu(Menu menu) { menu.add(0,"退出"); menu.add(0,1,"关于"); return true; } @Override public boolean onOptionsItemSelected(MenuItem item) { int item_id = item.getItemId(); switch (item_id) { case 0: MainActivity.this.finish(); break; case 1: new AlertDialog.Builder(this) .setIcon(R.drawable.ic_launcher) .setTitle("聚合天气 V3.0") .setMessage( "聚合天气API预报，\n桌面动态图标，\n图形天气预报界面。\n作者：黄颖\nQQ：84429027") .setPositiveButton("确定",null).show(); break; } return true; } String m1(int i) { return i < 10 ? "0" + i : "" + i; } String d1(int i) { return i < 10 ? "0" + i : "" + i; } private int getWeatherImage(String weather) { if (weather.indexOf("晴") != -1) return R.drawable.qing; if (weather.indexOf("阴") != -1) return R.drawable.yin; if (weather.indexOf("多云") != -1) return R.drawable.duoyun; if (weather.indexOf("阵雨") != -1) return R.drawable.zhenyu; if (weather.indexOf("中雨") != -1) return R.drawable.zhongyu; return R.drawable.ic_launcher; } private int getBgImage(String weather) { if (weather.indexOf("晴") != -1) return R.drawable.bgqing; if (weather.indexOf("阴") != -1) return R.drawable.bgyin; if (weather.indexOf("多云") != -1) return R.drawable.bgduoyun; if (weather.indexOf("雨") != -1) return R.drawable.bgrain; if (weather.indexOf("雪") != -1) return R.drawable.bgsnow; return R.drawable.ic_launcher; } public void click(View v) { Toast.makeText(getApplicationContext(),Toast.LENGTH_LONG).show(); new Thread(t).start(); } private final Handler PDD = new Handler() { @Override public void handleMessage(Message msg) { PD.dismiss(); } }; private final Handler PDS = new Handler() { @Override public void handleMessage(Message msg) { PD = ProgressDialog.show(MainActivity.this,null,"加载数据中，请稍等"); } }; } 原文链接：https://www.f2er.com/javaschema/285393.html