[移动开发]按钮的点击事件（接口（java））

package com.example.demo03;

import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.appcompat.app.AppCompatActivity;

import android.app.ProgressDialog;
import android.content.BroadcastReceiver;
import android.content.ComponentName;
import android.content.ContentResolver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.content.IntentSender;
import android.content.ServiceConnection;
import android.content.SharedPreferences;
import android.content.pm.ApplicationInfo;
import android.content.pm.PackageManager;
import android.content.res.AssetManager;
import android.content.res.Configuration;
import android.content.res.Resources;
import android.database.DatabaseErrorHandler;
import android.database.sqlite.SQLiteDatabase;
import android.graphics.Bitmap;
import android.graphics.drawable.Drawable;
import android.net.Uri;
import android.os.Bundle;
import android.os.Handler;
import android.os.Looper;
import android.os.UserHandle;
import android.view.Display;
import android.view.View;
import android.widget.Button;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;

public class MainActivity extends AppCompatActivity implements View.OnClickListener{



    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        findViewById(R.id.btn1).setOnClickListener(this);






    }


    @Override
    public void onClick(View view) {
        ProgressDialog prodialog;
        prodialog = new ProgressDialog(this);//构建对话框
        prodialog.setTitle("");
        prodialog.setIcon(R.mipmap.ic_launcher);
        prodialog.setMessage("正在登录请等候...");
        prodialog.setProgressStyle(ProgressDialog.STYLE_SPINNER);
        prodialog.show();
    }
}