具体代码如下：
activity_modify_psw.xml
?xml version="1.0" encoding="utf-8"? LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" android:background="@drawable/register_bg" android:orientation="vertical" include layout="@layout/main_title_bar" / EditText android:id="@+id/et_original_psw" android:layout_width="fill_parent" android:layout_height="48dp" android:layout_gravity="center_horizontal" android:layout_marginLeft="35dp" android:layout_marginRight="35dp" android:layout_marginTop="35dp" android:background="@drawable/register_user_name_bg" android:drawableLeft="@drawable/psw_icon" android:drawablePadding="10dp" android:gravity="center_vertical" android:hint="请输入原始密码" android:inputType="textPassword" android:paddingLeft="8dp" android:textColor="#000000" android:textColorHint="#a3a3a3" android:textSize="14sp" / EditText android:id="@+id/et_new_psw" android:layout_width="fill_parent" android:layout_height="48dp" android:layout_gravity="center_horizontal" android:layout_marginLeft="35dp" android:layout_marginRight="35dp" android:background="@drawable/register_psw_bg" android:drawableLeft="@drawable/psw_icon" android:drawablePadding="10dp" android:hint="请输入新密码" android:inputType="textPassword" android:paddingLeft="8dp" android:singleLine="true" android:textColor="#000000" android:textColorHint="#a3a3a3" android:textSize="14sp" / EditText android:id="@+id/et_new_psw_again" android:layout_width="fill_parent" android:layout_height="48dp" android:layout_gravity="center_horizontal" android:layout_marginLeft="35dp" android:layout_marginRight="35dp" android:background="@drawable/register_psw_again_bg" android:drawableLeft="@drawable/psw_icon" android:drawablePadding="10dp" android:hint="请再次输入新密码" android:inputType="textPassword" android:paddingLeft="8dp" android:singleLine="true" android:textColor="#000000" android:textColorHint="#a3a3a3" android:textSize="14sp" / Button android:id="@+id/btn_save" android:layout_width="fill_parent" android:layout_height="40dp" android:layout_gravity="center_horizontal" android:layout_marginLeft="35dp" android:layout_marginRight="35dp" android:layout_marginTop="15dp" android:background="@drawable/register_selector" android:text="保存" android:textColor="@android:color/white" android:textSize="18sp" / /LinearLayout
改密逻辑
思路
首先输入的原始密码与从 SharedPreferences 中读取的原始密码必须一致，输入的新密码与原始密码不能相同，再次输入的新密码与输入的新密码必须相同，以上条件都符合之后，点击保存修改 SharedPreferences 中的密码，修改密码后需要跳转到登录页，同时需要关闭修改密码页及设置页，我们需要在设置页的逻辑代码中新建一个 instance 对象，然后在创建设置页时给 instance 赋值 this ，再完成设置页的点击事件即可
具体代码如下：
ModifyActivity
package cn.edu.lt.android.boxueguapp.activity;import android.content.Intent;import android.content.SharedPreferences;import android.content.pm.ActivityInfo;import android.support.v7.app.AppCompatActivity;import android.os.Bundle;import android.text.TextUtils;import android.view.View;import android.widget.Button;import android.widget.EditText;import android.widget.TextView;import android.widget.Toast;import cn.edu.lt.android.boxueguapp.R;import cn.edu.lt.android.boxueguapp.utils.AnalysisUtils;import cn.edu.lt.android.boxueguapp.utils.MD5Utils;public class ModifyPswActivity extends AppCompatActivity { private TextView tv_main_title; private TextView tv_back; private EditText et_original_psw, et_new_psw, et_new_psw_again; private Button btn_save; private String originalPsw, newPsw, newPswAgain; private String userName; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_modify_psw); //设置此界面为竖屏 setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT); init; userName = AnalysisUtils.readLoginUserName(this); } /** * 获取界面控件并处理相关控件的点击事件 */ private void init { tv_main_title = (TextView) findViewById(R.id.tv_main_title); tv_main_title.setText("修改密码"); tv_back = (TextView) findViewById(R.id.tv_back); et_original_psw = (EditText) findViewById(R.id.et_original_psw); et_new_psw = (EditText) findViewById(R.id.et_new_psw); et_new_psw_again = (EditText) findViewById(R.id.et_new_psw_again); btn_save = (Button) findViewById(R.id.btn_save); tv_back.setOnClickListener(new View.OnClickListener { @Override public void onClick(View v) { ModifyPswActivity.this.finish; } }); //保存按钮的点击事件 btn_save.setOnClickListener(new View.OnClickListener { @Override public void onClick(View v) { getEditString; if (TextUtils.isEmpty(originalPsw)) { Toast.makeText(ModifyPswActivity.this, "请输入原始密码", Toast.LENGTH_SHORT).show; return; } else if (!MD5Utils.md5(originalPsw).equals(readPsw)) { Toast.makeText(ModifyPswActivity.this, "输入的密码与原始密码不一致", Toast.LENGTH_SHORT).show; return; } else if (MD5Utils.md5(newPsw).equals(readPsw)) { Toast.makeText(ModifyPswActivity.this, "输入的新密码与原始密码不能一致", Toast.LENGTH_SHORT).show; return; } else if (TextUtils.isEmpty(newPsw)) { Toast.makeText(ModifyPswActivity.this, "请输入新密码", Toast.LENGTH_SHORT).show; return; } else if (TextUtils.isEmpty(newPswAgain)) { Toast.makeText(ModifyPswActivity.this, "请再次输入新密码", Toast.LENGTH_SHORT).show; return; } else if (!newPsw.equals(newPswAgain)) { Toast.makeText(ModifyPswActivity.this, "两次输入的新密码不一致", Toast.LENGTH_SHORT).show; return; } else { Toast.makeText(ModifyPswActivity.this, "新密码设置成功", Toast.LENGTH_SHORT).show; //修改登录成功时保存在SharedPreferences中的密码 modifyPsw(newPsw); Intent intent = new Intent(ModifyPswActivity.this, LoginActivity.class); startActivity(intent); SettingActivity.instance.finish;//关闭设置页 ModifyPswActivity.this.finish;//关闭当前页面 }
