我想从API检索天气数据作为JSON，但它不起作用。如何将天气数据（例如5天预测）提取到文本视图中？
我的代码如下，但我需要以某种方式调整它以传递JSON 5天天气预报并将其放入文本视图中。
package mytweets.mytweets;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.params.BasicHttpParams;
import org.json.JSONArray;
import org.json.JSONObject;
import android.app.Activity;
import android.os.AsyncTask;
import android.os.Bundle;
import android.util.Base64;
import android.util.Log;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TextView;
public class MytweetsActivity extends Activity {
// we are reading weathe
final String URL `enter code here`="http://api.openweathermap.org/data/2.5/forecast/daily?q,gb&mode=json&units=metric&cnt=5&APPID=xxxxxxxxxxxxxxxx";
final String Consumer_Key = "mPfkAwVuuiVYeuZWdHAMzQ"; // change this if it does not work, you can get this from your twitter account at https://dev.twitter.com/apps/new
final String Consumer_Secret = "bkmiQqellGg9jnJFj41E8zukYSNk0FX1W7v1nU376rE"; // change this if it does not work, you can get this from your twitter account at https://dev.twitter.com/apps/new
JSONArray tweets = null; //an array of tweets
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_mytweets);
Button btn_token = (Button)findViewById(R.id.get_token);
btn_token.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
new GetTokenTask().execute();
}
});
Button btn_feed = (Button)findViewById(R.id.get_tweets);
btn_feed.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
TextView txt_token = (TextView)findViewById(R.id.txt_token);
String token = txt_token.getText().toString();
new GetTweetsTask().execute(token, URL);
}
});
}
protected class GetTokenTask extends AsyncTask<Void, Void, String> { // the class extends AsynTask in order to run as a thread in the background
@Override
protected String d
try {
DefaultHttpClient httpclient = new DefaultHttpClient(new BasicHttpParams());
HttpPost httppost = new HttpPost("https://api.twitter.com/oauth2/token"); //asks for a token
String apiString = Consumer_Key + ":" + Consumer_Secret;
String authorization = "Basic " + Base64.encodeToString(apiString.getBytes(), Base64.NO_WRAP); // twitter ants the authorization in bytes
httppost.setHeader("Authorization", authorization);
httppost.setHeader("Content-Type", "application/x-www-form-urlencoded;charset=UTF-8");
httppost.setEntity(new StringEntity("grant_type=client_credentials"));
InputStream inputStream = null;
HttpResponse response = httpclient.execute(httppost);
HttpEntity entity = response.getEntity();
inputStream = entity.getContent();
BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream, "UTF-8"), 8); // reading the input stream
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null)
{
sb.append(line + "\n");
}
return sb.toString();
}catch (Exception e){
Log.e("GetTokenTask", "Error:" + e.getMessage());
return null;
}
}
@Override
protected void onPostExecute(String jsonText){
try {
JSONObject root = new JSONObject(jsonText);
String bearer_token = root.getString("access_token");
TextView txt = (TextView)findViewById(R.id.txt_token);
txt.setText(bearer_token);
}catch (Exception e){
Log.e("GetTokenTask", "Error:" + e.getMessage());
}
}
}
protected class GetTweetsTask extends AsyncTask<String, Void, String> { //the class is run as a thread in the background to get the tweets
@Override
protected String doInBackground(String... params) {
try {
DefaultHttpClient httpclient = new DefaultHttpClient(new BasicHttpParams());
HttpGet httpget = new HttpGet(params[1]);
httpget.setHeader("Authorization", "Bearer " + params[0]);
httpget.setHeader("Content-type", "application/json"); //json content type
InputStream inputStream = null;
HttpResponse response = httpclient.execute(httpget);
HttpEntity entity = response.getEntity();
inputStream = entity.getContent();
BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream, "UTF-8"), 8);
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null)
{
sb.append(line + "\n");
}
return sb.toString();
}catch (Exception e){
Log.e("GetFeedTask", "Error:" + e.getMessage());
return null;
}
}
@Override
protected void onPostExecute(String jsonString){
try {
TextView txt_tweets = (TextView)findViewById(R.id.txt_tweets);
JSONObject forecastJson = new JSONObject(jsonString);
JSONArray forecastArray = forecastJson.getJSONArray("list");
String txt = "";
int i;
double minTemp, maxTemp;
// we are going to parse the json string and only display created_at and text. You can decide to display more objects if you want.
for (i=0;i<tweets.length();i++)
{
JSONObject dailyForecast = forecastArray.getJSONObject(i);
JSONObject tempObject = dailyForecast.getJSONObject("temp");
minTemp = tempObject.getDouble("min");
maxTemp = tempObject.getDouble("max");
//add these minTemp and maxTemp to array or the
//way you want to use
txt_tweets.setText(txt);
txt += "------------\n"; //separtors, check the output
}
}catch (Exception e){
Log.e("GetFeedTask", "Error:" + e.getMessage());
}
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.mytweets, menu);
return true;
}
}
答案 0 :(得分：1)
这是天气数据的JSON格式：
city: {
id: 2643743,
name: "London",
coord: {
lon: -0.12574,
lat: 51.50853
},
country: "GB",
population: 0
},
cod: "200",
message: 0.0268,
cnt: 5,
list: [
{
dt: 1448535600,
temp: {
day: 8.58,
min: 8.58,
max: 9.18,
night: 9.18,
eve: 8.58,
morn: 8.58
},
pressure: 1025.14,
humidity: 95,
weather: [
{
id: 500,
main: "Rain",
description: "light rain",
icon: "10d"
}
],
speed: 3.67,
deg: 224,
clouds: 92,
rain: 0.35
},
{},
{},
{},
{}
]
现在要访问天气数据（例如最小和最大温度），您需要解析如下：
JSONObject forecastJson = new JSONObject(jsonString);
JSONArray forecastArray = forecastJson.getJSONArray("list");
double minTemp, maxTemp;
for(int i = 0; i < forecastArray.length(); i++) {
JSONObject dailyForecast = forecastArray.getJSONObject(i);
JSONObject tempObject = dailyForecast.getJSONObject("temp");
minTemp = tempObject.getDouble("min");
maxTemp = tempObject.getDouble("max");
//add these minTemp and maxTemp to array or the
//way you want to use
}
如果您有任何疑问，请告诉我。
答案 1 :(得分：0)
使用数组和对象，并确保你有一个json解析器