习题4,3-5

log.xml 

<?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:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/user"
        android:text="用户名"
        android:textSize="20sp"
        />
    <EditText
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/userEdit"
        android:textSize="18sp"/>
    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/password"
        android:text="密码"
        android:textSize="20sp"
        />
    <EditText
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/passEdit"
        android:textSize="18sp"/>

</LinearLayout>

package com.example.ex3_5;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.LinearLayout;
import android.app.AlertDialog.Builder;
import android.widget.Toast;


public class MainActivity extends Activity {

    Button btn1, btn2;
    LinearLayout login;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        btn1 = findViewById(R.id.button1);
        btn2 = findViewById(R.id.button2);
        btn1.setOnClickListener(new mClick());
        btn2.setOnClickListener(new mClick());//复制代码时注意修改调用对象  btn1.setOnClickListener(new mClick());
    }

    class mClick implements OnClickListener {
        Builder dialog = new AlertDialog.Builder(MainActivity.this);

        public void onClick(View arg0) {
            if (arg0 == btn1) {
                dialog.setTitle("警告");
               // dialog.setIcon(R.drawable.icon1);
                dialog.setMessage("本项操作可能导致信息泄露!");
                dialog.setPositiveButton("确定", new okClick());
                dialog.create();
                dialog.show();
            } else if (arg0 == btn2) {

                login = (LinearLayout)getLayoutInflater().inflate(R.layout.log,null);
                dialog.setTitle("用户登录").setMessage("请输入用户名和密码").setView(login);
                dialog.setPositiveButton("确定", new loginClick());
                dialog.setNegativeButton("退出", new exitClick());
               // dialog.setIcon(R.drawable.icon2);
                dialog.create();
                dialog.show();
            }
        }


        class okClick implements DialogInterface.OnClickListener {
            public void onClick(DialogInterface dialog, int which) {
                dialog.cancel();
            }
        }

        class loginClick implements DialogInterface.OnClickListener {
            EditText txt;
            EditText pasw;

            public void onClick(DialogInterface dialog, int which) {
                txt = (EditText) login.findViewById(R.id.userEdit);//书本源代码中没有获取用户名进行判断
                pasw = (EditText) login.findViewById(R.id.passEdit);//密码
                if ((txt.getText().toString().equals("admin"))&&(pasw.getText().toString().equals("123456")))//书中源代码没有同时对用户名及密码进行判断
                    Toast.makeText(getApplicationContext(), "登录成功", Toast.LENGTH_SHORT).show();
                else
                    Toast.makeText(getApplicationContext(), "用户或密码输入错误", Toast.LENGTH_SHORT).show();
                dialog.dismiss();
            }
        }

        class exitClick implements DialogInterface.OnClickListener {
            public void onClick(DialogInterface dialog, int which) {
                MainActivity.this.finish();
            }

        }
    }
}

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_height="fill_parent"
    android:layout_width="fill_parent"
    android:gravity="center_horizontal"
    android:orientation="vertical"
    >
    <Button
        android:id="@+id/button1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="打开普通对话框"
        android:textSize="20sp"
        />
    <Button
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/button2"
        android:text="打开普通输入对话框"
        android:textSize="20sp"
        />
</LinearLayout>