关于Android Studio中简单的图片切换

真的太简单了，甚至没有使用到Adaper

activity.xml

<?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=".ImageActivity">

    <ImageView
        android:id="@+id/iv_image"
        android:layout_width="357dp"
        android:layout_height="383dp"
        android:layout_margin="10dp"
        android:layout_marginTop="64dp"
        android:foregroundGravity="center"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.49"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/tv_title"
        app:layout_constraintVertical_bias="0.617"
        tools:ignore="MissingConstraints" />

    <EditText
        android:id="@+id/et_image"
        android:layout_width="367dp"
        android:layout_height="54dp"
        android:hint="请输入"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.411"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/tv_title"
        app:layout_constraintVertical_bias="0.027"
        tools:ignore="MissingConstraints" />

    <Button
        android:id="@+id/button_image"
        android:layout_width="252dp"
        android:layout_height="56dp"
        android:backgroundTint="#00000000"
        android:text="查询"
        android:textColor="#888888"
        android:visibility="visible"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.423"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/tv_title"
        app:layout_constraintVertical_bias="0.162"
        tools:ignore="MissingConstraints" />

</androidx.constraintlayout.widget.ConstraintLayout>

.java

package com.example.metro;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageView;

public class ImageActivity extends AppCompatActivity implements View.OnClickListener {

    private ImageView iv_image;
    private EditText et_image;
    private Button button_imag;
    private int id = R.drawable.beijing;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_image);

        initView();
    }

    private void initView() {
        iv_image = findViewById(R.id.iv_image);
        et_image = findViewById(R.id.et_image);

        button_imag = findViewById(R.id.button_image);
        button_imag.setOnClickListener(this);
    }

    @Override
    public void onClick(View view) {
        String item = et_image.getText().toString();
        if("a".equals(item)){
            id = R.drawable.a;
        } else if("b".equals(item)){
            id = R.drawable.b;
        }  else {
            id = R.drawable.c;
        }
        iv_image.setImageResource(id);
    }
}