manifest:
<?xml version="1.0" encoding="utf-8"?>
package="com.example.manage"
android:versionCode="1"
android:versionName="1.0" >
android:minSdkVersion="8"
android:targetSdkVersion="17" />
<application
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<uses-library android:name="android.test.runner" />
<activity
android:name="my"
android:label="mine" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
mainactivity:
package com.example.manage;
import java.util.Map;
import com.example.manage.Utils;
import android.os.Bundle;
import android.app.Activity;
import android.content.DialogInterface;
import android.content.DialogInterface.OnClickListener;
import android.text.TextUtils;
import android.util.Log;
import android.view.View;
import android.widget.EditText;
import android.widget.Toast;
public class MainActivity extends Activity implements OnClickListener{
private EditText etNumber;
private EditText etPassword;
protected void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initView();
MapuserInfo=Utils.getUserInfo(this);
if(userInfo!=null){
etNumber.setText(userInfo.get("number"));
etPassword.setText(userInfo.get("password"));
}
}
private void initView(){
etNumber=(EditText) findViewById(R.id.et_number);
etPassword=(EditText) findViewById(R.id.et_password);
findViewById(R.id.btn_login).setOnClickListener((android.view.View.OnClickListener) this);
}
public void onClick(View v) {
// TODO Auto-generated method stub
String number=etNumber.getText().toString().trim();
String password=etPassword.getText().toString();
if(TextUtils.isEmpty(number)){
Toast.makeText(this,"請輸入QQ號碼",Toast.LENGTH_SHORT).show();
return;
}
if(TextUtils.isEmpty(password)){
Toast.makeText(this,"請輸入密碼",Toast.LENGTH_SHORT).show();
return;
}
Toast.makeText(this, "登陸成功", Toast.LENGTH_SHORT).show();
Log.i("MainActivity","記住密碼:"+number+","+password);
boolean isSaveSuccess=Utils.saveUserInfo(this,number,password);
if(isSaveSuccess){
Toast.makeText(this,"保存成功",Toast.LENGTH_SHORT).show();
}
else{
Toast.makeText(this, "保存失敗", Toast.LENGTH_SHORT).show();
}
}
@Override
public void onClick(DialogInterface arg0, int arg1) {
// TODO Auto-generated method stub
}
}
utils:
package com.example.manage;
import java.util.HashMap;
import java.util.Map;
import android.content.Context;
import android.content.SharedPreferences;
import android.content.SharedPreferences.Editor;
public class Utils {
public static boolean saveUserInfo(Context context,String number,String password){
SharedPreferences sp=context.getSharedPreferences("data", Context.MODE_PRIVATE);
Editor edit=sp.edit();
edit.putString("username", number);
edit.putString("pwd",password);
edit.commit();
return true;
}
public static MapgetUserInfo(Context context) {
SharedPreferences sp=context.getSharedPreferences("data", Context.MODE_PRIVATE);
String number=sp.getString("userName", null);
String password=sp.getString("pwd",null);
MapuserMap=new HashMap();
userMap.put("number",number);
userMap.put("password", password);
return userMap;
}
}
這個是書上sharedpreferences的例子,不知道哪裡錯了,書上說utils類要創建在新的一個包裡面,不知道到放在哪就跟mainactivity放在一個裡面了。
MainActivity.java
package com.example.manage;
import java.util.Map;
import android.app.Activity;
import android.os.Bundle;
import android.text.TextUtils;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
public class MainActivity extends Activity implements OnClickListener{
private EditText etNumber;
private EditText etPassword;
private Button etButton;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initView();
Map<String,String> userInfo=Utils.getUserInfo(this);
if(userInfo!=null){
etNumber.setText((String)userInfo.get("number"));
etPassword.setText((String)userInfo.get("password"));
}
}
private void initView(){
etNumber=(EditText) findViewById(R.id.et_number);
etPassword=(EditText) findViewById(R.id.et_password);
etButton=(Button)findViewById(R.id.btn_login);
etButton.setOnClickListener((android.view.View.OnClickListener) this);
}
public void onClick(View v) {
// TODO Auto-generated method stub
String number=etNumber.getText().toString().trim();
String password=etPassword.getText().toString();
if(TextUtils.isEmpty(number)){
Toast.makeText(this,"請輸入QQ號碼",Toast.LENGTH_SHORT).show();
return;
}
if(TextUtils.isEmpty(password)){
Toast.makeText(this,"請輸入密碼",Toast.LENGTH_SHORT).show();
return;
}
Toast.makeText(this, "登陸成功", Toast.LENGTH_SHORT).show();
Log.i("MainActivity","記住密碼:"+number+","+password);
boolean isSaveSuccess=Utils.saveUserInfo(this,number,password);
if(isSaveSuccess){
Toast.makeText(this,"保存成功",Toast.LENGTH_SHORT).show();
}
else{
Toast.makeText(this, "保存失敗", Toast.LENGTH_SHORT).show();
}
}
@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;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}
Utils.java
package com.example.manage;
import java.util.HashMap;
import java.util.Map;
import android.content.Context;
import android.content.SharedPreferences;
import android.content.SharedPreferences.Editor;
public class Utils {
public static boolean saveUserInfo(Context context,String number,String password){
SharedPreferences sp=context.getSharedPreferences("data", Context.MODE_PRIVATE);
Editor edit=sp.edit();
edit.putString("username", number);
edit.putString("pwd",password);
edit.commit();
return true;
}
public static Map<String,String> getUserInfo(Context context) {
SharedPreferences sp=context.getSharedPreferences("data", Context.MODE_PRIVATE);
String number=sp.getString("userName", null);
String password=sp.getString("pwd",null);
Map<String,String> userMap=new HashMap<String,String>();
userMap.put("number",number);
userMap.put("password", password);
return userMap;
}
}
改為這樣試試