问题遇到的现象和发生背景
如题，界面一登录成功跳转后变为图1的情况。
问题相关代码，请勿粘贴截图
package com.example.myapplication;
import androidx.appcompat.app.AppCompatActivity;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.net.Uri;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.CheckBox;
import android.widget.EditText;
import android.widget.Toast;
import java.util.ArrayList;
import java.util.List;
public class MainActivit extends AppCompatActivity {
private Button Login;
private EditText User,Password;
private CheckBox cbIsRememberPass;
private SharedPreferences sharedPreferences;
private List<Bean> data = new ArrayList<>();
@Override
protected void onCreate(Bundle savedInstanceState) {
// this.requestWindowFeature(Window.FEATURE_NO_TITLE);
// setContentView(R.layout.activity_login);
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initViews();
sharedPreferences=getSharedPreferences("rememberpassword",Context.MODE_PRIVATE);
boolean isRemember=sharedPreferences.getBoolean("rememberpassword",false);
if(isRemember){
String user=sharedPreferences.getString("user","");
String password=sharedPreferences.getString("password","");
User.setText(user);
Password.setText(password);
cbIsRememberPass.setChecked(true);
}
User = findViewById(R.id.user);
Password = findViewById(R.id.password);
Login = findViewById(R.id.login);
Login.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
String user = User.getText().toString();
String password = Password.getText().toString();
if (user.length() == 0) {
Toast.makeText(MainActivit.this, "用户名不能为空", Toast.LENGTH_SHORT).show();
} else if (password.length() == 0) {
Toast.makeText(MainActivit.this, "密码不能为空", Toast.LENGTH_SHORT).show();
} else if ((Password.getText().toString().trim()).equals(User.getText().toString().trim())) {
SharedPreferences.Editor editor=sharedPreferences.edit();
if(cbIsRememberPass.isChecked()){
editor.putBoolean("rememberpassword",true);
editor.putString("user",user);
editor.putString("password",password);
Intent intent = new Intent();
intent.setClass(MainActivit.this, MyAdapter.class);
startActivity(intent);
}else {
editor.clear();
} editor.commit();
finish();
Toast.makeText(MainActivit.this, "登录成功", Toast.LENGTH_SHORT).show();
Intent intent = new Intent();
intent.setClass(MainActivit.this, MainActivity.class);
startActivity(intent);
MainActivit.this.finish();
} else {
Toast.makeText(MainActivit.this, "两次输入的密码不一致", Toast.LENGTH_SHORT).show();
}
}
});
}
private void initViews() {
User=(EditText)findViewById(R.id.user);
Password=(EditText)findViewById(R.id.password);
cbIsRememberPass=(CheckBox) findViewById(R.id.cbIsRememberPass);
}
public void callPhone (View view){
Intent intent = new Intent();
intent.setAction(Intent.ACTION_DIAL);
intent.setData(Uri.parse("tel:07713246041"));
startActivity(intent);
}
}
package com.example.myapplication;
import androidx.appcompat.app.AppCompatActivity;
import androidx.recyclerview.widget.LinearLayoutManager;
import androidx.recyclerview.widget.RecyclerView;
import android.os.Bundle;
import java.util.ArrayList;
import java.util.List;
public class MainActivity extends AppCompatActivity {
private List<Bean> data = new ArrayList<>();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main2);
for(int i=0;i<1000;i++){
Bean bean =new Bean();
bean.setName("11"+i);
data.add(bean);
}
RecyclerView recyclerView = findViewById(R.id.rv);
LinearLayoutManager linearLayoutManager = new LinearLayoutManager(this);
recyclerView.setLayoutManager(linearLayoutManager);
MyAdapter myAdapter=new MyAdapter(data,this);
recyclerView.setAdapter(myAdapter);
}
}
<?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:orientation="vertical">
<TextView
android:id="@+id/tv"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:textSize="30sp" />
</LinearLayout>
<?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=".MainActivit">
<TextView
android:id="@+id/GXCME"
android:layout_width="303dp"
android:layout_height="38dp"
android:text=""
android:textAlignment="center"
android:textSize="24sp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintVertical_bias="0.038" />
<ImageView
android:id="@+id/imageView"
android:layout_width="184dp"
android:layout_height="114dp"
android:layout_marginTop="20dp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.484"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/GXCME"
app:srcCompat="@drawable/gxcme" />
<TextView
android:id="@+id/textView"
android:layout_width="74dp"
android:layout_height="23dp"
android:layout_marginStart="36dp"
android:layout_marginTop="40dp"
android:text="用户名："
android:textSize="17sp"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/imageView" />
<TextView
android:id="@+id/textView2"
android:layout_width="75dp"
android:layout_height="20dp"
android:layout_marginStart="32dp"
android:layout_marginTop="32dp"
android:text="密码："
android:textSize="17sp"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/textView" />
<EditText
android:id="@+id/password"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="8dp"
android:ems="10"
android:inputType="textPassword"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.4"
app:layout_constraintStart_toEndOf="@+id/textView2"
app:layout_constraintTop_toBottomOf="@+id/user" />
<EditText
android:id="@+id/user"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="28dp"
android:ems="10"
android:inputType="textPersonName"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.406"
app:layout_constraintStart_toEndOf="@+id/textView"
app:layout_constraintTop_toBottomOf="@+id/imageView" />
<Button
android:id="@+id/button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:onClick="callPhone"
android:text="服务电话："
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/password"
app:layout_constraintVertical_bias="0.95" />
<Button
android:id="@+id/login"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="84dp"
android:layout_marginTop="20dp"
android:text="登录"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/linearLayout" />
<Button
android:id="@+id/rege"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="64dp"
android:layout_marginTop="20dp"
android:text="注册"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.0"
app:layout_constraintStart_toEndOf="@+id/login"
app:layout_constraintTop_toBottomOf="@+id/linearLayout" />
<LinearLayout
android:id="@+id/linearLayout"
android:layout_width="333dp"
android:layout_height="67dp"
android:orientation="vertical"
app:layout_constraintBottom_toTopOf="@+id/button"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.642"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/cbIsRememberPass"
app:layout_constraintVertical_bias="0.267">
<RadioGroup
android:id="@+id/radioButton7"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
<RadioButton
android:id="@+id/radioButton4"
android:layout_width="330dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:focusable="false"
android:text="学生" />
<RadioButton
android:id="@+id/radioButton5"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="教师" />
</RadioGroup>
</LinearLayout>
<CheckBox
android:id="@+id/cbIsRememberPass"
android:layout_width="137dp"
android:layout_height="29dp"
android:layout_marginTop="24dp"
android:text="记住账号密码"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.498"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/password" />
</androidx.constraintlayout.widget.ConstraintLayout>
