diff --git a/src/net/micode/notes/ui/ChangingPassword.java b/src/net/micode/notes/ui/ChangingPassword.java
new file mode 100644
index 0000000..54c869b
--- /dev/null
+++ b/src/net/micode/notes/ui/ChangingPassword.java
@@ -0,0 +1,71 @@
+package net.micode.notes.ui;
+
+import android.app.Activity;
+import android.content.Intent;
+import android.content.SharedPreferences;
+import android.os.Bundle;
+import android.view.View;
+import android.view.WindowManager;
+import android.widget.Button;
+import android.widget.EditText;
+import android.widget.Toast;
+
+import net.micode.notes.R;
+
+public class ChangingPassword extends Activity{
+    EditText OldPassword;
+    EditText NewPassword;
+    EditText AckPassword;
+    Button Acknowledged;
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState){
+        super.onCreate(savedInstanceState);
+        setContentView(R.layout.activity_change_password);
+        getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_ADJUST_RESIZE
+                | WindowManager.LayoutParams.SOFT_INPUT_STATE_VISIBLE);
+        OldPassword=(EditText) findViewById(R.id.old_password);
+        NewPassword=(EditText) findViewById(R.id.new_password);
+        AckPassword=(EditText) findViewById(R.id.ack_password);
+        Acknowledged=(Button)findViewById(R.id.Acknowledged);
+        Acknowledged.setOnClickListener(new View.OnClickListener() {
+            @Override
+            public void onClick(View v) {
+                String old_password = OldPassword.getText().toString();
+                String new_password = NewPassword.getText().toString();
+                String ack_password = AckPassword.getText().toString();
+                SharedPreferences pref = getSharedPreferences("user management",MODE_PRIVATE);
+                        String login_password = pref.getString("password","");
+                if(old_password.equals("")==true || new_password.equals("")==true || ack_password.equals("")==true) {
+                    Toast.makeText(ChangingPassword.this, "密码不能为空", Toast.LENGTH_SHORT).show();
+                }
+                else if (new_password.equals(ack_password) == false) {
+                    Toast.makeText(ChangingPassword.this, "新建密码与重复密码不匹配,请重新输入密码", Toast.LENGTH_SHORT).show();
+                            AckPassword.setText("");
+                }
+                else if(old_password.equals(login_password) == false){
+                    Toast.makeText(ChangingPassword.this, "原有密码错误,请重新输入密码", Toast.LENGTH_SHORT).show();
+                            OldPassword.setText("");
+                }
+                else if (new_password.equals(ack_password) == true &&
+                        old_password.equals(login_password) == true){
+                    SharedPreferences.Editor editor=getSharedPreferences("user management", MODE_PRIVATE).edit();
+                            editor.putString("password",new_password);
+                    editor.apply();
+                    Toast.makeText(ChangingPassword.this, "修改密码成功",Toast.LENGTH_SHORT).show();
+                    Intent intent=new
+                            Intent(ChangingPassword.this,NotesListActivity.class);
+                    startActivity(intent);
+                    finish();
+                }
+            }
+        });
+    }
+    @Override
+    public void onBackPressed(){
+        Intent intent=new Intent(ChangingPassword.this,NotesListActivity.class);
+        startActivity(intent);
+        finish();
+    }
+}
+
diff --git a/src/net/micode/notes/ui/DeletingPassword.java b/src/net/micode/notes/ui/DeletingPassword.java
index 0058bba..82cbb76 100644
--- a/src/net/micode/notes/ui/DeletingPassword.java
+++ b/src/net/micode/notes/ui/DeletingPassword.java
@@ -31,13 +31,10 @@ public class DeletingPassword extends Activity {
                 if(text02.equals("")==true)
                     Toast.makeText(DeletingPassword.this, "密码不能为空",
                             Toast.LENGTH_SHORT).show();
-                SharedPreferences pref=getSharedPreferences("user
-                        management",MODE_PRIVATE);
+                SharedPreferences pref=getSharedPreferences("user management",MODE_PRIVATE);
                         String password = pref.getString("password","");
                 if(password.equals("")==false&&password.equals(text02)==true){
-                    SharedPreferences.Editor editor=getSharedPreferences("user
-                            management",
-                            MODE_PRIVATE).edit();
+                    SharedPreferences.Editor editor=getSharedPreferences("user management", MODE_PRIVATE).edit();
                     editor.putBoolean("user",false);//false 表示已经设置登录密码
                     editor.putString("password","");
                     editor.apply();
diff --git a/src/net/micode/notes/ui/LoginActivity.java b/src/net/micode/notes/ui/LoginActivity.java
index 98555f8..d87b98c 100644
--- a/src/net/micode/notes/ui/LoginActivity.java
+++ b/src/net/micode/notes/ui/LoginActivity.java
@@ -8,18 +8,19 @@ import android.view.WindowManager;
 import android.widget.Button;
 import android.widget.EditText;
 import android.widget.Toast;
+import android.app.Activity;
 
 import net.micode.notes.R;
 
-public class LoginActivity {
+public class LoginActivity extends Activity{
 
     EditText lgn_password;
     Button lgn_login;
 
     @Override
-    protected void onCreate(Bundle saverInstanceState) {
+    protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
-        SharedPreferences pref = getSharedPreferences("user managemet", MODE_PRIVATE);
+        SharedPreferences pref = getSharedPreferences("user management", MODE_PRIVATE);
         boolean User_boolean = pref.getBoolean("user", false); //检查用户是否设置了密码
         if (!User_boolean) {  //如果用户没有设置密码,则直接跳转到便签主界面
             Intent intent = new Intent(LoginActivity.this, NotesListActivity.class);
@@ -29,7 +30,7 @@ public class LoginActivity {
 
         setContentView(R.layout.activity_login);
         getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_VISIBLE | WindowManager.LayoutParams.SOFT_INPUT_ADJUST_RESIZE);
-        lgn_password = (EditTExt) findViewById(R.id.lgn_password);
+        lgn_password = (EditText)findViewById(R.id.lgn_password);
         lgn_login = (Button) findViewById(R.id.login);
         lgn_login.setOnClickListener(new View.OnClickListener() {
                                          @Override
diff --git a/src/net/micode/notes/ui/NoteEditText.java b/src/net/micode/notes/ui/NoteEditText.java
index 07060b5..84a8239 100644
--- a/src/net/micode/notes/ui/NoteEditText.java
+++ b/src/net/micode/notes/ui/NoteEditText.java
@@ -187,9 +187,10 @@ public class NoteEditText extends EditText {
         if (mOnTextViewChangeListener != null) {
             if (!focused && TextUtils.isEmpty(getText())) {
                 mOnTextViewChangeListener.onTextChange(mIndex, false);
-            } else {
+            }
+            else {
                 mOnTextViewChangeListener.onTextChange(mIndex, true);
-            }9
+            }
         }
         super.onFocusChanged(focused, direction, previouslyFocusedRect);
     }