我已经制作了一个Android应用程序来登录数据库，我需要它在单击按钮时重定向到用户个人资料页面，到目前为止它只显示一条消息，表示登录成功然后确实没有其他的。我在下面的三个代码片段是应用程序的XML，同一页面的Java和BackgroundWorker，其中完成了许多基础工作。有人可以告诉我如何重定向到名为Activity_user_profile.xml的页面吗？
编辑回答：
我添加了一行：startActivity（new Intent（this，UserProfileActivity.class））;对于我的onLogin方法，这允许我将它链接到我想要的页面
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/activity_main"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="com.example.programmingknowledge.finalyearproject2017.MainActivity">
<Button
android:text="Register"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/btnRegister"
android:onClick="OpenReg"
android:layout_below="@+id/btnLogin"
android:layout_alignLeft="@+id/btnLogin"
android:layout_alignStart="@+id/btnLogin"
android:layout_alignParentRight="true"
android:layout_alignParentEnd="true" />
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:ems="10"
android:id="@+id/et_doctor_number"
android:layout_alignParentTop="true"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:hint="Doctor number "
android:layout_alignParentRight="true"
android:layout_alignParentEnd="true"
android:inputType="number" />
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:inputType="textPassword"
android:ems="10"
android:id="@+id/et_Password"
android:layout_below="@+id/et_doctor_number"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_alignParentRight="true"
android:layout_alignParentEnd="true"
android:hint="Password" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Login"
android:id="@+id/btnLogin"
android:onClick="OnLogin"
android:layout_below="@+id/et_Password"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_alignParentRight="true"
android:layout_alignParentEnd="true" />
</RelativeLayout>
主要活动：
package com.example.programmingknowledge.finalyearproject2017;
import android.content.Intent;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.EditText;
public class MainActivity extends ActionBarActivity {
EditText EmailEt, PasswordEt;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
EmailEt = (EditText) findViewById(R.id.et_doctor_number);
PasswordEt = (EditText) findViewById(R.id.et_Password);
}
public void OnLogin(View view){
String email = EmailEt.getText().toString();
String password = PasswordEt.getText().toString();
String type = "Login";
BackgroundWorker backgroundWorker = new BackgroundWorker(this);
backgroundWorker.execute(type, email, password);
startActivity(new Intent(this,UserProfileActivity.class));
}
public void OpenReg(View view){
startActivity(new Intent(this,Register.class));
}
}
Background Worker:
package com.example.programmingknowledge.finalyearproject2017;
import android.content.Context;
import android.os.AsyncTask;
import android.app.AlertDialog;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLEncoder;
/**
* Created by john on 25-Feb-17.
*/
public class BackgroundWorker extends AsyncTask<String, Void, String> {
Context context;
AlertDialog alertDialog;
BackgroundWorker (Context ctx){
context = ctx;
}
@Override
protected String doInBackground(String... params) {
String type = params[0];
String login_url = "http://10.0.2.2/login.php";
String register_url = "http://10.0.2.2/register.php";
if (type.equals("login")){
try {
String email = params[1];
String password = params[2];
URL url = new URL(login_url);
HttpURLConnection httpURLConnection = (HttpURLConnection)url.openConnection();
httpURLConnection.setRequestMethod("POST");
httpURLConnection.setDoOutput(true);
httpURLConnection.setDoInput(true);
OutputStream outputStream = httpURLConnection.getOutputStream();
BufferedWriter bufferedWriter = new BufferedWriter(new OutputStreamWriter(outputStream, "utf-8"));
String post_data = URLEncoder.encode("email", "UTF-8")+"="+URLEncoder.encode(email, "utf-8")+"&"+URLEncoder.encode("password", "UTF-8")+"="+URLEncoder.encode(password, "utf-8");
bufferedWriter.write(post_data);
bufferedWriter.flush();
bufferedWriter.close();
outputStream.close();
InputStream inputStream = httpURLConnection.getInputStream();
BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(inputStream,"iso-8859-1"));
String result ="";
String line ="";
while ((line=bufferedReader.readLine())!=null){
result+=line;
}
bufferedReader.close();
inputStream.close();
httpURLConnection.disconnect();
return result;
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e){
e.printStackTrace();
}
} else if(type.equals("register")){
try {
String patient_name = params[1];
String check_in_date = params[2];
String room_number = params[3];
String bed_number = params[4];
String notes = params[5];
URL url = new URL(register_url);
HttpURLConnection httpURLConnection = (HttpURLConnection)url.openConnection();
httpURLConnection.setRequestMethod("POST");
httpURLConnection.setDoOutput(true);
httpURLConnection.setDoInput(true);
OutputStream outputStream = httpURLConnection.getOutputStream();
BufferedWriter bufferedWriter = new BufferedWriter(new OutputStreamWriter(outputStream, "utf-8"));
String post_data = URLEncoder.encode("patient_name", "UTF-8")+"="+URLEncoder.encode(patient_name, "utf-8")+"&"
+ URLEncoder.encode("check_in_date", "UTF-8")+"="+URLEncoder.encode(check_in_date, "utf-8")+"&"
+ URLEncoder.encode("room_number", "UTF-8")+"="+URLEncoder.encode(room_number, "utf-8")+"&"
+ URLEncoder.encode("bed_number", "UTF-8")+"="+URLEncoder.encode(bed_number, "utf-8")+"&"
+ URLEncoder.encode("notes", "UTF-8")+"="+URLEncoder.encode(notes, "utf-8");
bufferedWriter.write(post_data);
bufferedWriter.flush();
bufferedWriter.close();
outputStream.close();
InputStream inputStream = httpURLConnection.getInputStream();
BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(inputStream,"iso-8859-1"));
String result ="";
String line ="";
while ((line=bufferedReader.readLine())!=null){
result+=line;
}
bufferedReader.close();
inputStream.close();
httpURLConnection.disconnect();
return result;
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e){
e.printStackTrace();
}
}
return null;
}
@Override
protected void onPreExecute() {
alertDialog = new AlertDialog.Builder(context).create();
alertDialog.setMessage("Login Status");
}
@Override
protected void onPostExecute(String result) {
alertDialog.setMessage(result);
alertDialog.show();
}
@Override
protected void onProgressUpdate(Void... values) {
super.onProgressUpdate(values);
}
}
答案 0 :(得分：0)
on on on onSostExecute，Call Intent to go your Userprofile Activity
@Override
protected void onPostExecute(String result) {
alertDialog.setMessage(result);
alertDialog.show();
activity.startActivity(new Intent(activity,UserProfile.class));
}