我開發一個應用程序中,我需要管理用戶的會話即當在第一次用戶登錄,他必須看到登錄頁面,一旦他被認證,他將被重定向到主屏幕和在共享首選項中設置一個值。現在,當用戶點擊退出按鈕在主屏幕上shsredpreferences的值必須被清除,下一次用戶打開他必須直接登錄page.Unless應用程序,直到用戶點擊註銷他一定不會顯示在登錄頁面。 我能夠存儲在sharedpreferences值,但無法將其刪除。值不被清除
這裏是我的loginpage.java
package com.sess.eg;
import android.app.Activity;
import android.content.Intent;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.preference.PreferenceManager;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
public class loginpage extends Activity {
/** Called when the activity is first created. */
EditText acc,user,pin;
Button login;
StringBuilder builder = new StringBuilder();
String UserName;
SharedPreferences.Editor prefs;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// SharedPreferences prefs1 = getPreferences(MODE_WORLD_READABLE);
// UserName= prefs1.getString("User", "Abcdef");
//
// System.out.println(UserName);
//
// if(UserName.equals("Ad"))
//
// {
// System.out.println(UserName);
// Intent i=new Intent(loginpage.this,homepage.class);
// startActivity(i);
// }
setContentView(R.layout.main);
acc = (EditText) findViewById(R.id.ed_login_acc);
user = (EditText) findViewById(R.id.ed_user_acc);
pin = (EditText) findViewById(R.id.ed_pin_acc);
login = (Button) findViewById(R.id.login_button);
SharedPreferences prefs1 = getPreferences(MODE_WORLD_READABLE);
login.setOnClickListener(new Button.OnClickListener(){
public void onClick(View v) {
prefs.putString("User", "Ad");
prefs.commit();
//System.out.println(sendJson1());
//startService(new Intent(Login.this, MyService.class));
Intent i = new Intent(loginpage.this, homepage.class);
startActivity(i);
finish();
//System.out.println(UserName);
}
});
}
@Override
protected void onStart() {
SharedPreferences prefs1 = getPreferences(MODE_WORLD_READABLE);
UserName= prefs1.getString("User", "Abcdef");
System.out.println(UserName);
if(UserName.equals("Ad"))
{
System.out.println(UserName);
Intent i=new Intent(loginpage.this,homepage.class);
startActivity(i);
finish();
}
super.onStart();
}
}
here is my code for homepage.java
package com.sess.eg;
import android.app.Activity;
import android.content.Intent;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
public class homepage extends Activity{
Button logout;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.home3);
logout = (Button) findViewById(R.id.logout);
logout.setOnClickListener(new Button.OnClickListener(){
public void onClick(View v) {
SharedPreferences.Editor prefs = getPreferences(MODE_WORLD_WRITEABLE).edit();
prefs.clear();
// prefs.commit();
SharedPreferences prefs1 = getPreferences(MODE_WORLD_READABLE);
String UserName= prefs1.getString("User", "Abcdef");
System.out.println(UserName);
finish();
}
});
}
}
[讓我爲你做嗎?](http://samir-mangroliya.blogspot.in/p/android-shared-preferences.html) –
感謝samir的回覆它將值保存在sharedpreferences中並維護會話,但是如何在用戶點擊註銷時清除sharedpreferences中的值? –
閱讀明文數據 –