layout代码:
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" 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" android:orientation="vertical" tools:context="com.example.my.testapp.Test_Delu"> <LinearLayout android:layout_width="match_parent" android:layout_height="wrap_content" android:orientation="horizontal"> <TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="用户名:"/> <EditText android:layout_width="0dp" android:layout_height="wrap_content" android:layout_weight="1" android:id="@+id/et_1"/> </LinearLayout> <LinearLayout android:layout_width="match_parent" android:layout_height="wrap_content" android:orientation="horizontal"> <TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="密码:" /> <EditText android:layout_width="0dp" android:layout_height="wrap_content" android:layout_weight="1" android:id="@+id/et_2" android:inputType="textPassword"/> </LinearLayout> <Button android:layout_width="match_parent" android:layout_height="wrap_content" android:text="登录" android:onClick="bt2_onClick"/> </LinearLayout>
Activity代码:
package com.example.my.testapp; import android.content.SharedPreferences; import android.support.v7.app.AppCompatActivity; import android.os.Bundle; import android.view.View; import android.widget.EditText; import android.widget.Toast; public class Test_Delu extends AppCompatActivity { EditText et_1,et_2; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_test__delu); et_1=(EditText)findViewById(R.id.et_1); et_2=(EditText)findViewById(R.id.et_2); SharedPreferences sd=getSharedPreferences("用户名", MODE_PRIVATE); String c=sd.getString("用户名",null); et_1.setText(c); } public void bt2_onClick(View v) { EditText et_1=(EditText)findViewById(R.id.et_1); EditText et_2=(EditText)findViewById(R.id.et_1); String a=et_1.getText().toString(); String b=et_2.getText().toString(); if (a==null||a.trim().length()==0||b==null||b.trim().length()==0) { Toast.makeText(Test_Delu.this, "请正确输入用户名或密码", Toast.LENGTH_SHORT).show(); } else { SharedPreferences sp=getSharedPreferences("用户名", MODE_APPEND); SharedPreferences.Editor editor=sp.edit(); editor.putString("用户名",a); editor.commit(); Toast.makeText(Test_Delu.this, "登录成功。", Toast.LENGTH_SHORT).show(); } } }