Android 作业03

<?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=".MainActivity">

    <Button
        android:id="@+id/btn_one"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginBottom="156dp"
        android:background="#ff8fa0"
        android:text="Log in"
        android:textColor="#ffffff"
        android:textStyle="bold"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.498"
        app:layout_constraintStart_toStartOf="parent" />

    <EditText
        android:id="@+id/editText2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginBottom="340dp"
        android:ems="10"
        android:hint=" Please enter your ID."
        android:inputType="textPassword"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent" />

    <EditText
        android:id="@+id/editText"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="44dp"
        android:ems="10"
        android:hint=" enter your PIN."
        android:inputType="textPassword"
        app:layout_constraintEnd_toEndOf="@+id/editText2"
        app:layout_constraintTop_toBottomOf="@+id/editText2" />

    <ImageView
        android:id="@+id/imageView2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginBottom="65dp"
        app:layout_constraintBottom_toTopOf="@+id/editText2"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        tools:srcCompat="@tools:sample/avatars[8]" />

</androidx.constraintlayout.widget.ConstraintLayout>

package com.example.myapplication;

import androidx.appcompat.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity {
    private EditText username;
    private EditText password;
    private Button btn;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        username = (EditText) findViewById(R.id.editText2);
        password = (EditText) findViewById(R.id.editText);
        btn = (Button) findViewById(R.id.btn_one);

        btn.setOnClickListener(new View.OnClickListener() {
            public void onClick(View view) {
                String strUsername = username.getText().toString();
                String strPassword = password.getText().toString();
                //判断正误
                if (strUsername.equals("bigyellow") && strPassword.equals("123456")) {
                    Toast.makeText(MainActivity.this, "login successfully", Toast.LENGTH_SHORT).show();
                } else {
                    Toast.makeText(MainActivity.this, "login failure", Toast.LENGTH_SHORT).show();
                }

                btn.setOnClickListener(new View.OnClickListener() {
                    @Override
                    public void onClick(View view) {
                        finish();
                    }
                });
            }
        });
    }
}