我在android中做了一个String替换方法，但是没有用。它显示与输入相同的输出（无变化）。
替换方法位于代码的最后几行。我在这里尝试将“mon”替换为“MONDAY”，“tue”替换为“TUESDAY”....等等，我的代码如下：
Main.java
public class MainActivity extends Activity {
String temperature, date, condition, humidity, wind, link;
Bitmap icon = null;
TextView title, tempText, dateText, conditionText, windText, humidityText,
weatherLink, day1, day2, day3, day4, day5, day6, day7;
ImageView image;
TextView temp1, temp2, temp3, temp4, temp5, txt1, txt2, txt3, txt4, txt5;
ArrayList<String> weather = new ArrayList<String>();
ProgressDialog dialog;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
image = (ImageView) findViewById(R.id.icon);
title = (TextView) findViewById(R.id.weather_title);
dateText = (TextView) findViewById(R.id.dateText);
tempText = (TextView) findViewById(R.id.tempText);
conditionText = (TextView) findViewById(R.id.conditionText);
humidityText = (TextView) findViewById(R.id.humidityText);
windText = (TextView) findViewById(R.id.windText);
day1 = (TextView) findViewById(R.id.day1);
day2 = (TextView) findViewById(R.id.day2);
day3 = (TextView) findViewById(R.id.day3);
day4 = (TextView) findViewById(R.id.day4);
temp1 = (TextView) findViewById(R.id.temp1);
temp2 = (TextView) findViewById(R.id.temp2);
temp3 = (TextView) findViewById(R.id.temp3);
temp4 = (TextView) findViewById(R.id.temp4);
temp5 = (TextView) findViewById(R.id.temp5);
txt1 = (TextView) findViewById(R.id.txt1);
txt2 = (TextView) findViewById(R.id.txt2);
txt3 = (TextView) findViewById(R.id.txt3);
txt3 = (TextView) findViewById(R.id.txt4);
txt3 = (TextView) findViewById(R.id.txt5);
weatherLink = (TextView) findViewById(R.id.weatherLink);
/*
* Typeface tf = Typeface.createFromAsset(getAssets(),
* “Fonts/Roboto-Condensed.ttf”);
*/
title.setText("My Weather Report");
/*
* tempText.setTypeface(tf); conditionText.setTypeface(tf);
* dateText.setTypeface(tf); humidityText.setTypeface(tf);
* windText.setTypeface(tf); title.setTypeface(tf);
* day1.setTypeface(tf); day2.setTypeface(tf); day3.setTypeface(tf);
* day4.setTypeface(tf);
*/
ImageButton backBtn = (ImageButton) findViewById(R.id.backBtn);
ImageButton report = (ImageButton) findViewById(R.id.reportBtn);
new retrieve_weatherTask().execute();
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
protected class retrieve_weatherTask extends
AsyncTask<Void, String, String> {
@Override
protected void onPreExecute() {
// TODO Auto-generated method stub
super.onPreExecute();
dialog = new ProgressDialog(MainActivity.this);
dialog.setTitle("Please wait...");
dialog.show();
}
@Override
protected String doInBackground(Void... params) {
// TODO Auto-generated method stub
String qResult = "";
HttpClient httpClient = new DefaultHttpClient();
HttpContext localContext = new BasicHttpContext();
HttpGet httpGet = new HttpGet(
"http://weather.yahooapis.com/forecastrss?w=2295425&u=c”");
try {
HttpResponse response = httpClient.execute(httpGet,
localContext);
HttpEntity entity = response.getEntity();
if (entity != null) {
InputStream inputStream = entity.getContent();
Reader in = new InputStreamReader(inputStream);
BufferedReader bufferedreader = new BufferedReader(in);
StringBuilder stringBuilder = new StringBuilder();
String stringReadLine = null;
while ((stringReadLine = bufferedreader.readLine()) != null) {
stringBuilder.append(stringReadLine + "\n");
}
qResult = stringBuilder.toString();
}
} catch (ClientProtocolException e) {
e.printStackTrace();
Toast.makeText(MainActivity.this, e.toString(),
Toast.LENGTH_LONG).show();
} catch (IOException e) {
e.printStackTrace();
Toast.makeText(MainActivity.this, e.toString(),
Toast.LENGTH_LONG).show();
}
Document dest = null;
DocumentBuilderFactory dbFactory = DocumentBuilderFactory
.newInstance();
DocumentBuilder parser;
try {
parser = dbFactory.newDocumentBuilder();
dest = parser
.parse(new ByteArrayInputStream(qResult.getBytes()));
} catch (ParserConfigurationException e1) {
e1.printStackTrace();
Toast.makeText(MainActivity.this, e1.toString(),
Toast.LENGTH_LONG).show();
} catch (SAXException e) {
e.printStackTrace();
Toast.makeText(MainActivity.this, e.toString(),
Toast.LENGTH_LONG).show();
} catch (IOException e) {
e.printStackTrace();
Toast.makeText(MainActivity.this, e.toString(),
Toast.LENGTH_LONG).show();
}
Node temperatureNode = dest.getElementsByTagName(
"yweather:condition").item(0);
temperature = temperatureNode.getAttributes().getNamedItem("temp")
.getNodeValue().toString();
Node tempUnitNode = dest.getElementsByTagName("yweather:units")
.item(0);
temperature = temperature
+ "°"
+ tempUnitNode.getAttributes().getNamedItem("temperature")
.getNodeValue().toString();
Node dateNode = dest.getElementsByTagName("yweather:forecast")
.item(0);
date = dateNode.getAttributes().getNamedItem("date").getNodeValue()
.toString();
Node conditionNode = dest
.getElementsByTagName("yweather:condition").item(0);
condition = conditionNode.getAttributes().getNamedItem("text")
.getNodeValue().toString();
Node humidityNode = dest
.getElementsByTagName("yweather:atmosphere").item(0);
humidity = humidityNode.getAttributes().getNamedItem("humidity")
.getNodeValue().toString();
humidity = humidity + "%";
Node windNode = dest.getElementsByTagName("yweather:wind").item(0);
wind = windNode.getAttributes().getNamedItem("speed")
.getNodeValue().toString();
Node windUnitNode = dest.getElementsByTagName("yweather:units")
.item(0);
wind = wind
+ " "
+ windUnitNode.getAttributes().getNamedItem("speed")
.getNodeValue().toString();
String desc = dest.getElementsByTagName("item").item(0)
.getChildNodes().item(13).getTextContent().toString();
StringTokenizer str = new StringTokenizer(desc, "<=>");
System.out.println("Tokens: " + str.nextToken("=>"));
String src = str.nextToken();
System.out.println("src: " + src);
String url1 = src.substring(1, src.length() - 2);
Pattern TAG_REGEX = Pattern.compile("(.+?)<br />");
Matcher matcher = TAG_REGEX.matcher(desc);
while (matcher.find()) {
weather.add(matcher.group(1));
}
Pattern links = Pattern.compile("(.+?)<BR/>");
matcher = links.matcher(desc);
while (matcher.find()) {
System.out.println("Match Links: " + (matcher.group(1)));
link = matcher.group(1);
}
/*
* String test = (Html.fromHtml(desc)).toString();
* System.out.println(“test: “+ test); StringTokenizer tkn = new
* StringTokenizer(test); for(int i=0; i < tkn.countTokens(); i++){
* System.out.println(“Remaining: “+tkn.nextToken()); }
*/
InputStream in = null;
try {
// in = OpenHttpConnection(url1);
int response = -1;
URL url = new URL(url1);
URLConnection conn = url.openConnection();
if (!(conn instanceof HttpURLConnection))
throw new IOException("Not an HTTP connection");
HttpURLConnection httpConn = (HttpURLConnection) conn;
httpConn.setAllowUserInteraction(false);
httpConn.setInstanceFollowRedirects(true);
httpConn.setRequestMethod("GET");
httpConn.connect();
response = httpConn.getResponseCode();
if (response == HttpURLConnection.HTTP_OK) {
System.out.println("*********************");
in = httpConn.getInputStream();
}
icon = BitmapFactory.decodeStream(in);
in.close();
} catch (IOException e1) {
e1.printStackTrace();
}
return qResult;
}
protected void onPostExecute(String result) {
System.out.println("POST EXECUTE");
if (dialog.isShowing() && dialog != null)
dialog.dismiss();
tempText.setText("Temperature:" + temperature);
conditionText.setText("Condition: " + condition);
dateText.setText("Date: " + date);
humidityText.setText("Humidity: " + humidity);
windText.setText("Wind: " + wind);
// image.setImageBitmap(icon);
String three = weather.get(3);
String four = weather.get(4);
String five = weather.get(5);
String six = weather.get(6);
System.out.println(":::::::thusday:::::" + weather.get(3));
System.out.println(":::::::friday:::::" + weather.get(4));
System.out.println(":::::::satrday:::::" + weather.get(5));
System.out.println(":::::::sunday:::::" + weather.get(6));
// DAY1
String[] parts1 = three.split("-");
String th1 = parts1[0]; // 004
String th22 = parts1[1];
String[] sub1 = th22.split(". H");
String t1 = sub1[0];
String t2 = sub1[1];
System.out.println(":::::::;Part 1:::::::::" + t1);
System.out.println(":::::::;Part 1:::::::::" + t2);
day1.setText(weekdaygen(th1.trim()));
System.out.println("::::::::::::::::REPLACE:::::::" + th1);
temp1.setText("H" + t2);
txt1.setText(t1);
/*
* // DAY2 String[] parts2 = four.split("-"); String th2 =
* parts2[0]; // 004 String th23 = parts2[1]; String[] sub2 =
* th23.split(". "); String t3 = sub2[0]; String t4 = sub2[1];
*
* day2.setText(th2); temp2.setText(t4); txt2.setText(t3);
*
* // DAY4 String[] parts4 = five.split("-"); String th4 =
* parts4[0]; // 004 String th25 = parts4[1]; String[] sub4 =
* th25.split(". "); String t7 = sub4[0]; String t8 = sub4[1];
*
* day3.setText(th4); temp3.setText(t8); txt3.setText(t7);
*
* // DAY5 String[] parts5 = five.split("-"); String th5 =
* parts5[0]; // 004 String th26 = parts5[1]; String[] sub5 =
* th26.split(". "); String t9 = sub5[0]; String t10 = sub5[1];
*
* day4.setText(th5); temp4.setText(t10); txt4.setText(t9);
*
* day1.setText(weather.get(3)); day2.setText(weather.get(4));
* day3.setText(weather.get(5)); day4.setText(weather.get(6));
*
*
*
* day5.setText(weather.get(1)); day6.setText(weather.get(2));
*/
weatherLink.setText(Html.fromHtml(link));
}
}
String weekdaygen(String s) {
if (s.equals("Mon")) {
s.replace("mon", "MONDAY");
}
if (s.equals("Tue")) {
s.replace("Tue", "TUESDAY");
}
if (s.equals("Wed")) {
s.replace("Wed", "WEDNESDAY");
}
if (s.equals("Thu")) {
s.replace("Thu", "THURSDAY");
}
if (s.equals("Fri")) {
s.replace("Fri", "FRIDAY");
}
if (s.equals("Sat")) {
s.replace("Sat", "SATURDAY");
}
if (s.equals("Sun")) {
s.replace("Sun", "SUNDAY");
}
return s;
}
}
答案 0 :(得分：2)
String weekdaygen(String s) {
if (s.equals("Mon")) {
s=s.replace("mon", "MONDAY");
}
if (s.equals("Tue")) {
s= s.replace("Tue", "TUESDAY");
}
if (s.equals("Wed")) {
s=s.replace("Wed", "WEDNESDAY");
}
if (s.equals("Thu")) {
s=s.replace("Thu", "THURSDAY");
}
if (s.equals("Fri")) {
s=s.replace("Fri", "FRIDAY");
}
if (s.equals("Sat")) {
s=s.replace("Sat", "SATURDAY");
}
if (s.equals("Sun")) {
s=s.replace("Sun", "SUNDAY");
}
return s;
}
使用此代码
Java中的字符串是不可变的 - 当您调用replace时，它不会更改现有字符串的内容 - 它会返回带有修改的新字符串。所以你想要：s=s.replace("mon", "MONDAY");
答案 1 :(得分：1)
由于字符串是不可变的，因此替换函数会在替换后创建一个新字符串并返回它。
将您的功能更改为后续操作：
String weekdaygen(String s) {
if (s.equals("Mon")) {
s=s.replace("mon", "MONDAY");
}
//same for rest of them
return s;
}