Andriod猜歌达人，登录传值跳转

activity_login.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent" >

    <EditText
        android:id="@+id/username_et"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="请输入用户名" />

    <EditText
        android:id="@+id/pwd_et"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_below="@id/username_et"
        android:hint="请输入密码"
        android:password="true" />

    <Button
        android:id="@+id/register_btn"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@id/pwd_et"
        android:text="注册" />

    <Button
        android:id="@+id/login_btn"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@id/pwd_et"
        android:layout_centerHorizontal="true"
        android:layout_toRightOf="@id/register_btn"
        android:text="登录" />

</RelativeLayout>

LoginActivity.java

package com.briup.test1;


import android.app.Activity;
import android.content.DialogInterface;
import android.content.Intent;
import android.view.View.OnClickListener;import android.os.Bundle;
import android.text.TextUtils;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

public class LoginActivity extends Activity implements OnClickListener{
	private Button loginBtn, registerBtn;
	private EditText nameEt, pwdEt;
	private String name,pwd;
	private Bundle bundle= new Bundle();
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_login);
		loginBtn = (Button) findViewById(R.id.login_btn);
		registerBtn = (Button) findViewById(R.id.register_btn);
		nameEt = (EditText) findViewById(R.id.username_et);
		pwdEt = (EditText) findViewById(R.id.pwd_et);
		loginBtn.setOnClickListener(this);
		registerBtn.setOnClickListener(this);

	}
	//判断用户名和密码是否为空
	public boolean submit() {
		name = nameEt.getText().toString().trim();
		pwd = pwdEt.getText().toString().trim();
		if (TextUtils.isEmpty(name) || TextUtils.isEmpty(pwd)) {
			Toast.makeText(this, "请输入用户名和密码", Toast.LENGTH_SHORT).show();
			return false;
		}
		return true;
	}
	@Override
	public void onClick(View v) {
		if(!submit()) return;
		int id = v.getId();
		switch (id) {
		case R.id.login_btn:
			Intent intent = new Intent(LoginActivity.this , MainActivity.class);
			Toast.makeText(this, "登录成功", Toast.LENGTH_SHORT).show();
			//传递用户名
			name = nameEt.getText().toString().trim();
			bundle.putString("username_et",name);
			intent.putExtras(bundle); 
			
			startActivity(intent);
			break;
		case R.id.register_btn:
			Toast.makeText(this, "注册成功", Toast.LENGTH_SHORT).show();
		default:
			break;
		}
	}
}

划重点：

1.activity_login.xml每个按钮和文本的id值

2.对每个按钮和文本进行定义变量，类型的强制转换，点击监听

                loginBtn = (Button) findViewById(R.id.login_btn);
		registerBtn = (Button) findViewById(R.id.register_btn);
		nameEt = (EditText) findViewById(R.id.username_et);
		pwdEt = (EditText) findViewById(R.id.pwd_et);
		loginBtn.setOnClickListener(this);
		registerBtn.setOnClickListener(this);

3.创建Bundle对象

private Bundle bundle= new Bundle();

4.判断用户名和密码是否为空

	//判断用户名和密码是否为空
	public boolean submit() {
		name = nameEt.getText().toString().trim();
		pwd = pwdEt.getText().toString().trim();
		if (TextUtils.isEmpty(name) || TextUtils.isEmpty(pwd)) {
			Toast.makeText(this, "请输入用户名和密码", Toast.LENGTH_SHORT).show();
			return false;
		}
		return true;
	}

5.点击事件的中，注意传参方式

case R.id.login_btn:
			Intent intent = new Intent(LoginActivity.this , MainActivity.class);
			Toast.makeText(this, "登录成功", Toast.LENGTH_SHORT).show();
			//传递用户名
			name = nameEt.getText().toString().trim();
			bundle.putString("username_et",name);
			intent.putExtras(bundle); 
			
			startActivity(intent);
			break;