android布局不带参数返回

package com.example.lesson3_4;

import java.util.ArrayList;
import java.util.List;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.LinearLayout;
import android.widget.TextView;

public class MainActivity extends Activity {

    // <>里面内容1.7必须 SDK>4.4  就可以不用写

    List<Post> mList = new ArrayList<Post>();
    // 布局中的组件
    LinearLayout titles;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        initData();
        // 关键布局
        titles = (LinearLayout) findViewById(R.id.titles);
        for (int i = 0; i < mList.size(); i++) {
            // 使用for创建多个TextView
            TextView tv = new TextView(this);
            // 分别设置值
            tv.setText(mList.get(i).getTitle());
            // 布局可以动态的添加多个组件
            titles.addView(tv);
            final Post post = mList.get(i);
            tv.setOnClickListener(new OnClickListener() {

                @Override
                public void onClick(View v) {
                    // 为每一个TextView设置一个点击事件
                    Intent intent = new Intent(MainActivity.this,
                            ContentActivity.class);
                    // 如果需要携带数据，可以通过intent的put方法
                    // Bundle
                    // 一个对象需要传递，必须实现序列化
                    // 内部类访问局部变量必须final
                    intent.putExtra("post", post);
                    startActivity(intent);
                }
            });
        }

    }

    private void initData() {
        // 加载数据
        for (int i = 0; i < 3; i++) {
            mList.add(new Post("标题" + (i + 1), "内容" + (i + 1)));
        }
    }
}

package com.example.lesson3_4;

import java.io.Serializable;

public class Post implements Serializable {

    private static final long serialVersionUID = -2278908915637867413L;
    String title;
    String content;

    public String getTitle() {
        return title;
    }
    public void setTitle(String title) {
        this.title = title;
    }
    public String getContent() {
        return content;
    }
    public void setContent(String content) {
        this.content = content;
    }
    public Post(String title, String content) {
        super();
        this.title = title;
        this.content = content;
    }
    @Override
    public String toString() {
        return "Post [title=" + title + ", content=" + content + "]";
    }

}

package com.example.lesson3_4;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.ImageView;
import android.widget.TextView;

public class ContentActivity extends Activity {

    TextView title, content;
    ImageView iv_back;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_content);
        // 关键布局组件
        title = (TextView) findViewById(R.id.title);
        content = (TextView) findViewById(R.id.content);
        iv_back = (ImageView) findViewById(R.id.iv_back);
        // 获取前一个activity传递的数据
        Intent intent = getIntent();
        Post post = (Post) intent.getSerializableExtra("post");
        // 为布局组件设置值
        title.setText(post.getTitle());
        content.setText(post.getContent());

        // 为ImageView设置点击事件并且返回activity
        iv_back.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                finish();
            }
        });
    }

}

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:id="@+id/titles"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="com.example.lesson3_4.MainActivity" />

<?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" >

    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="50dp" >

        <TextView
            android:id="@+id/title"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_centerInParent="true"
            android:padding="5dp"
            android:text="标题"
            android:textSize="18sp" />

        <ImageView
            android:id="@+id/iv_back"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_centerVertical="true"
            android:layout_marginLeft="10dp"
            android:src="@drawable/arrow_left" />
    </RelativeLayout>

    <View
        android:layout_width="match_parent"
        android:layout_height="1px"
        android:background="#CCC" />

    <TextView
        android:id="@+id/content"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />

</LinearLayout>

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.lesson3_4"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="15"
        android:targetSdkVersion="21" />

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name=".MainActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <activity android:name="com.example.lesson3_4.ContentActivity" >
        </activity>
    </application>

</manifest>