我正在尝试从我的应用程序到Mysql上的数据库建立连接。但我看不到来自应用程序的任何Toast响应或结果。感谢
这是mainActivity.java
public class MainActivity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
public void userReg(View view){
startActivity(new Intent(this,Register.class));
}
}
Background.java
public class Background extends AsyncTask<String,Void,String> {
Context ctx;
Background(Context ctx){
this.ctx = ctx;
}
@Override
protected String doInBackground(String... params) {
String reg_url = "http://10.0.2.2/AndroidDB/register.php";
String log_url = "http://10.0.2.2/AndroidDB/login.php";
String method = params[0];
if(method.equals("register")) {
String name = params[1];
String username = params[2];
String password = params[3];
try {
URL url = new URL(reg_url);
HttpURLConnection httpURLConnection=(HttpURLConnection)url.openConnection();
httpURLConnection.setRequestMethod("POST");
httpURLConnection.setDoOutput(true);
OutputStream OS = httpURLConnection.getOutputStream();
BufferedWriter bufferedWriter = new BufferedWriter(new OutputStreamWriter(OS,"UTF-8"));
String data = URLEncoder.encode("name","UTF-8") +"="+URLEncoder.encode(name,"UTF-8")+"&"+
URLEncoder.encode("username","UTF-8") +"="+URLEncoder.encode(username,"UTF-8")+"&"+
URLEncoder.encode("password","UTF-8") +"="+URLEncoder.encode(password,"UTF-8");
bufferedWriter.write(data);
bufferedWriter.flush();
bufferedWriter.close();
OS.close();
InputStream IS = httpURLConnection.getInputStream();
IS.close();
return "Registration Success....";
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (ProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
return null;
}
@Override
protected void onPreExecute() {
super.onPreExecute();
}
@Override
protected void onProgressUpdate(Void... values) {
super.onProgressUpdate(values);
}
@Override
protected void onPostExecute(String result) {
Toast.makeText(ctx,result,Toast.LENGTH_LONG).show();
}
}
这是Register.java
public class Register extends AppCompatActivity {
EditText et_Name, et_UserName, et_Userpass;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_register);
et_Name =(EditText)findViewById(R.id.name);
et_UserName =(EditText)findViewById(R.id.userName);
et_Userpass =(EditText)findViewById(R.id.userPass);
}
public void userReg (View view) {
String name = et_Name.getText().toString();
String username = et_UserName.getText().toString();
String password = et_Userpass.getText().toString();
String method = "register";
Background background= new Background(this);
background.execute(method,name,username,password);
finish();
}
}
我没有看到错误，但我也看不到结果请帮忙。
答案 0 :(得分：0)
复制此课程：
public class HttpClient {
private static JSONObject response = null;
public static JSONObject SendHttpGET(String url) {
response = null;
try {
URL obj = new URL(url);
HttpURLConnection con = (HttpURLConnection) obj.openConnection();
con.setRequestMethod("GET");
con.setRequestProperty("Accept", "application/json");
con.setRequestProperty("Content-type", "application/json");
BufferedReader in = new BufferedReader(new InputStreamReader(con.getInputStream()));
String inputLine;
StringBuffer sb = new StringBuffer();
while ((inputLine = in.readLine()) != null) {
sb.append(inputLine);
}
in.close();
response = new JSONObject(sb.toString());
} catch (Exception e) {
e.printStackTrace();
// Crashlytics.logException(e);
}
return response;
}
public static JSONObject SendHttpPost(String URL, List<NameValuePair> param) {
System.out.println("!!-- req=>" +URL + " - " + param.toString());
try {
HttpParams params = new BasicHttpParams();
HttpConnectionParams.setConnectionTimeout(params, 15000);
HttpConnectionParams.setSoTimeout(params, 10000);
DefaultHttpClient httpclient = new DefaultHttpClient(params);
HttpPost httpPostRequest = new HttpPost(URL);
httpPostRequest.setEntity(new UrlEncodedFormEntity(param));
/* StringEntity se;
se = new StringEntity(param.toString());
httpPostRequest.setEntity(se);*/
//httpPostRequest.setHeader("Accept", "application/json");
//httpPostRequest.setHeader("Content-type", "application/json");
httpPostRequest.setHeader("Accept-Encoding", "gzip");
HttpResponse response = (HttpResponse) httpclient.execute(httpPostRequest);
HttpEntity entity = response.getEntity();
if (entity != null) {
InputStream instream = entity.getContent();
Header contentEncoding = response.getFirstHeader("Content-Encoding");
if (contentEncoding != null && contentEncoding.getValue().equalsIgnoreCase("gzip")) {
instream = new GZIPInputStream(instream);
}
String resultString = convertStreamToString(instream);
instream.close();
resultString = resultString.substring(0, resultString.length() - 1);
System.out.println("!!-- res11=>" + resultString.toString());
JSONObject jsonObjRecv = new JSONObject(resultString);
System.out.println("!!-- res=>" + jsonObjRecv.toString());
return jsonObjRecv;
}
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
private static String convertStreamToString(InputStream is) {
BufferedReader reader = new BufferedReader(new InputStreamReader(is));
StringBuilder sb = new StringBuilder();
String line = null;
try {
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
is.close();
} catch (IOException e) {
e.printStackTrace();
}
}
return sb.toString();
}
}
然后在活动（内部类）中添加以下 Asynctask 类
public class RegisterAsynctask extends AsyncTask<String,Void,JSONObject> {
@Override
protected void onPreExecute() {
super.onPreExecute();
baseActivity.showProgressDialog();
name = et_Name.getText().toString();
username = et_UserName.getText().toString();
password = et_Userpass.getText().toString();
method = "register";
}
@Override
protected JSONObject doInBackground(String... params) {
try {
List<NameValuePair> req_params = new ArrayList<NameValuePair>();
req_params.add(new BasicNameValuePair("name", name));
req_params.add(new BasicNameValuePair("username", username));
req_params.add(new BasicNameValuePair("password", ""+password));
req_params.add(new BasicNameValuePair("method", method));
JSONObject response = HttpClient.SendHttpPost(your_url, req_params);
if (response != null) {
return response;
}
}catch(Exception e){
e.printStackTrace();
}
return null;
}
@Override
protected void onPostExecute(JSONObject res) {
super.onPostExecute(res);
baseActivity.dismissProgressDialog();
Toast.makeText(getApplicationContext(), res.toString(), Toast.LENGTH_LONG).show();
}
}
现在通过 userReg（）方法调用此方法：
new RegisterAsynctask().execute();