Android studio登录注册页面和启动页面的实现
不多说了，直接放代码：
布局文件：
这里我把启动页放在了activity_main里：
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@drawable/start"
tools:context=".MainActivity"/>
activity_login:
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".loginActivity">
<LinearLayout
android:layout_width="409dp"
android:layout_height="729dp"
android:orientation="vertical"
tools:layout_editor_absoluteX="1dp"
tools:layout_editor_absoluteY="1dp">
<EditText
android:id="@+id/user"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:maxLines="2"
android:hint="账号："
/>
<EditText
android:id="@+id/password"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:inputType="textPassword"
android:maxLines="2"
android:hint="密码："
/>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal">
<Button
android:id="@+id/b1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="Login"
android:textAllCaps="false"/>
<Button
android:id="@+id/b2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="Register"
android:textAllCaps="false"/>
</LinearLayout>
</LinearLayout>
</androidx.constraintlayout.widget.ConstraintLayout>
activity_register:
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".registerActivity">
<LinearLayout
android:layout_width="409dp"
android:layout_height="729dp"
android:orientation="vertical"
tools:layout_editor_absoluteX="1dp"
tools:layout_editor_absoluteY="1dp">
<EditText
android:id="@+id/user1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:hint="用户名：" />
<EditText
android:id="@+id/password1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:hint="密码：" />
<EditText
android:id="@+id/password2"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:hint="重复密码：" />
<androidx.constraintlayout.widget.ConstraintLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<Button
android:id="@+id/b3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="注册"
tools:layout_editor_absoluteX="150dp"
tools:layout_editor_absoluteY="4dp" />
</androidx.constraintlayout.widget.ConstraintLayout>
</LinearLayout>
</androidx.constraintlayout.widget.ConstraintLayout>
MainActivity:
package com.example.mylogin;
import android.content.Intent;
import android.os.Bundle;
import android.os.Handler;
import android.view.WindowManager;
import androidx.appcompat.app.ActionBar;
import androidx.appcompat.app.AppCompatActivity;
public class MainActivity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
getWindow().addFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN);//隐藏状态栏
setContentView(R.layout.activity_main );
ActionBar actionBar = getSupportActionBar();
if (actionBar != null)
{
actionBar.hide();
}
new Handler().postDelayed(new Runnable() {
@Override
public void run() {
Intent mainIntent = new Intent(MainActivity.this, loginActivity.class);//从启动界面跳转到登录界面
startActivity(mainIntent);
finish();
}
}, 3000);//系统休眠3秒
}
}
loginActivity:
package com.example.mylogin;
import androidx.appcompat.app.AppCompatActivity;
import android.content.Intent;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.text.TextUtils;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
public class loginActivity extends AppCompatActivity {
private String userName,psw,spPsw;
private EditText user,password;//引入EditText控件
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login);
user=findViewById(R.id.user);
password=findViewById(R.id.password);
Button b1 = (Button) findViewById(R.id.b1);
b1.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
getText();
spPsw=readPsw(userName);
if(TextUtils.isEmpty(userName)){
Toast.makeText(loginActivity.this, "请输入用户名", Toast.LENGTH_SHORT).show();
return;
}else if(TextUtils.isEmpty(psw)){
Toast.makeText(loginActivity.this, "请输入密码", Toast.LENGTH_SHORT).show();
return;
}else if(psw.equals(spPsw)){
Toast.makeText(loginActivity.this, "登录成功", Toast.LENGTH_SHORT).show();
return;
}else if((spPsw!=null&&!TextUtils.isEmpty(spPsw)&&!psw.equals(spPsw))){
Toast.makeText(loginActivity.this, "输入的用户名和密码不一致", Toast.LENGTH_SHORT).show();
return;
}else{
Toast.makeText(loginActivity.this, "此用户名不存在", Toast.LENGTH_SHORT).show();
}
}
});
Button b2 = (Button) findViewById(R.id.b2);
b2.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Intent intent = new Intent(loginActivity.this,registerActivity.class);//从登录页面跳转到注册页面
startActivity(intent);
}
});
}
private void getText(){
userName=user.getText().toString().trim();
psw=password.getText().toString().trim();
}
private String readPsw(String userName){
SharedPreferences sp=getSharedPreferences("loginInfo", MODE_PRIVATE);
return sp.getString(userName , "");
}
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if(data!=null){
//是获取注册界面回传过来的用户名
String userName=data.getStringExtra("userName");
if(!TextUtils.isEmpty(userName)){
}
}
}
}
registerActivity:
package com.example.mylogin;
import androidx.appcompat.app.AppCompatActivity;
import android.content.Intent;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.text.TextUtils;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
public class registerActivity extends AppCompatActivity {
private EditText user1,password1,password2;
private String userName,passWord1,passWord2;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_register);
user1=findViewById(R.id.user1);
password1=findViewById(R.id.password1);
password2=findViewById(R.id.password2);
Button b3 = (Button)findViewById(R.id.b3);
b3.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
getEditText();//获取EditText控件上的文本
if(TextUtils.isEmpty(userName)){
Toast.makeText(registerActivity.this, "请输入用户名", Toast.LENGTH_SHORT).show();
return;
}else if(TextUtils.isEmpty(passWord1)){
Toast.makeText(registerActivity.this, "请输入密码", Toast.LENGTH_SHORT).show();
return;
}else if(TextUtils.isEmpty(passWord2)){
Toast.makeText(registerActivity.this, "请再次输入密码", Toast.LENGTH_SHORT).show();
return;
}else if(!passWord1.equals(passWord2)) {
Toast.makeText(registerActivity.this, "输入两次的密码不一样", Toast.LENGTH_SHORT).show();
return;
}else if (isExitUserName(userName)){
Toast.makeText(registerActivity.this,"此账户已经存在",Toast.LENGTH_SHORT).show();
}else{
Toast.makeText(registerActivity.this, "注册成功", Toast.LENGTH_SHORT).show();
//把账号、密码和账号标识保存到sp里面
/**
* 保存账号和密码到SharedPreferences中
*/
saveRegisterInfo(userName, passWord1);
Intent data = new Intent();
data.putExtra("userName", userName);
setResult(RESULT_OK, data);
registerActivity.this.finish();
}
}
});
}
//读取EditText中的文本内容
private void getEditText(){
userName=user1.getText().toString().trim();
passWord1=password1.getText().toString().trim();
passWord2=password2.getText().toString().trim();
}
//将账号密码保存到SharePreferences
private void saveRegisterInfo(String userName,String psw){
SharedPreferences sp=getSharedPreferences("loginInfo", MODE_PRIVATE);
SharedPreferences.Editor editor=sp.edit();
editor.putString(userName, psw);
editor.commit();
}
//从SharePreferen中读取用户名，判断用户名是否已经被注册
private boolean isExitUserName(String userName){
boolean exit_userName=false;
SharedPreferences sp = getSharedPreferences("loginInfo",MODE_PRIVATE);
String psw=sp.getString(userName,"");
if(!TextUtils.isEmpty(psw)){
exit_userName=true;
}
return exit_userName;
}
}