Android Fragment实现按钮间的切换

原文地址：http://blog.csdn.net/a123demi/article/details/32693037

Fragment要点

Fragment是activity的界面中的一部分或一种行为。你可以把多个Fragment们组合到一个activity中来创建一个多面界面并且你可以在多个activity中重用一个Fragment。你可以把Fragment认为模块化的一段activity，它具有自己的生命周期，接收它自己的事件，并可以在activity运行时被添加或删除。

Fragment不能独立存在，它必须嵌入到activity中，而且Fragment的生命周期直接受所在的activity的影响。例如：当activity暂停时，它拥有的所有的Fragment们都暂停了，当activity销毁时，它拥有的所有Fragment们都被销毁。然而，当activity运行时（在onResume()之后，onPause()之前），你可以单独地操作每个Fragment，比如添加或删除或替代(add(),remove(),replace())它们。当你在执行上述针对Fragment的事务时，你可以将事务添加到一个棧中，这个栈被activity管理，栈中的每一条都是一个Fragment的一次事务。有了这个栈，就可以反向执行Fragment的事务，这样就可以在Fragment级支持“返回”键（向后导航）。

而本文简单介绍主要通过点击不同按钮实现切换对应的fragment的效果，类似用Tab的切换：

主要代码如下：

1.工程源代码显示：



2.编译后效果图





3.切换按钮布局：activity_bottom_bts.xml切换的按钮显示在底部

[html] view
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<span style="font-family:SimSun;"><span style="font-size:18px;"><?xmlversionxmlversion="1.0" encoding="utf-8"?>

<LinearLayoutxmlns:androidLinearLayoutxmlns:android="http://schemas.android.com/apk/res/android"

android:layout_width="match_parent"

android:layout_height="match_parent"

android:orientation="horizontal">

<Button

android:id="@+id/movie_btn"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_weight="1"

android:gravity="center"

android:text="@string/movie"/>

<Button

android:id="@+id/tv_btn"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_weight="1"

android:gravity="center"

android:text="@string/tv"/>

<Button

android:id="@+id/anime_btn"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_weight="1"

android:gravity="center"

android:text="@string/anime"/>

<Button

android:id="@+id/variety_btn"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_weight="1"

android:gravity="center"

android:text="@string/variety" />

</LinearLayout></span></span>

4.主界面activity_main.xml

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<span style="font-family:SimSun;"><span style="font-size:18px;"><RelativeLayoutxmlns:androidRelativeLayoutxmlns:android="http://schemas.android.com/apk/res/android"

xmlns:tools="http://schemas.android.com/tools"

android:layout_width="match_parent"

android:layout_height="match_parent"

android:paddingBottom="@dimen/activity_vertical_margin"

android:paddingLeft="@dimen/activity_horizontal_margin"

android:paddingRight="@dimen/activity_horizontal_margin"

android:paddingTop="@dimen/activity_vertical_margin"

tools:context="com.example.switchfragmentdemo.MainActivity$PlaceholderFragment">

<LinearLayout

android:id="@+id/button_view_include"

android:layout_width="fill_parent"

android:layout_height="wrap_content"

android:layout_alignParentBottom="true"

>

<includelayoutincludelayout="@layout/activity_bottom_btns" />

</LinearLayout>

<FrameLayout

android:id="@+id/fragment_content"

android:layout_width="match_parent"

android:layout_height="fill_parent"

android:layout_alignParentTop="true"

android:layout_marginBottom="50dp"

android:layout_below="@id/button_view_include"

>

</FrameLayout>

</RelativeLayout></span></span>

5.strings.xml

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<span style="font-family:SimSun;"><span style="font-size:18px;"><?xmlversionxmlversion="1.0" encoding="utf-8"?>

<resources>

<stringnamestringname="app_name">SwitchFragmentDemo</string>

<stringnamestringname="hello_world">Hello world!</string>

<stringnamestringname="action_settings">Settings</string>

<string name="movie">电影</string>

<string name="tv">电视剧</string>

<string name="anime">动漫</string>

<string name="variety">综艺</string>

<stringnamestringname="movie_view">这是一个电影界面</string>

<string name="tv_view">这是一个电视剧界面</string>

<stringnamestringname="anime_view">这是一个动漫界面</string>

<stringnamestringname="variety_view">这是一个综艺界面</string>

</resources></span></span>

6.主界面实现代码：MainActivity.Java

[java] view
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<span style="font-family:SimSun;"><span style="font-size:18px;">packagecom.example.myandroidswitchbtndemo;

importjava.util.ArrayList;

importjava.util.List;

importandroid.annotation.SuppressLint;

importandroid.app.Activity;

importandroid.app.FragmentManager;

importandroid.app.FragmentTransaction;

importandroid.graphics.Color;

importandroid.os.Bundle;

importandroid.view.Menu;

importandroid.view.MenuItem;

importandroid.view.View;

importandroid.view.View.OnClickListener;

importandroid.widget.Button;

@SuppressLint("NewApi")

public classMainActivity extends Activity implements OnClickListener {

private Button movieBtn, tvBtn,animeBtn, varietyBtn;

private List<Button> btnList = newArrayList<Button>();

private FragmentManager fm;

private FragmentTransaction ft;

@Override

protected void onCreate(BundlesavedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

findById();

// 進入系統默認為movie

fm = getFragmentManager();

ft = fm.beginTransaction();

setBackgroundColorById(R.id.movie_btn);

ft.replace(R.id.fragment_content,new MovieFragment());

ft.commit();

}

private void findById() {

movieBtn = (Button)this.findViewById(R.id.movie_btn);

tvBtn = (Button)this.findViewById(R.id.tv_btn);

animeBtn = (Button) this.findViewById(R.id.anime_btn);

varietyBtn = (Button)this.findViewById(R.id.variety_btn);

movieBtn.setOnClickListener(this);

tvBtn.setOnClickListener(this);

animeBtn.setOnClickListener(this);

varietyBtn.setOnClickListener(this);

btnList.add(movieBtn);

btnList.add(tvBtn);

btnList.add(animeBtn);

btnList.add(varietyBtn);

}

private void setBackgroundColorById(intbtnId) {

for (Button btn : btnList) {

if (btn.getId() == btnId){

btn.setBackgroundColor(Color.GREEN);

}else {

btn.setBackgroundColor(Color.BLUE);

}

}

}

@Override

public boolean onCreateOptionsMenu(Menumenu) {

// Inflate the menu; this addsitems to the action bar if it is present.

getMenuInflater().inflate(R.menu.main,menu);

return true;

}

@Override

public booleanonOptionsItemSelected(MenuItem item) {

// Handle action bar item clickshere. The action bar will

// automatically handle clicks onthe Home/Up button, so long

// as you specify a parentactivity in AndroidManifest.xml.

int id = item.getItemId();

if (id == R.id.action_settings) {

return true;

}

returnsuper.onOptionsItemSelected(item);

}

@Override

public void onClick(View v) {

// TODO Auto-generated methodstub

fm = getFragmentManager();

ft = fm.beginTransaction();

switch (v.getId()) {

case R.id.movie_btn:

setBackgroundColorById(R.id.movie_btn);

ft.replace(R.id.fragment_content,new MovieFragment());

break;

case R.id.tv_btn:

setBackgroundColorById(R.id.tv_btn);

ft.replace(R.id.fragment_content,new TVFragment());

break;

case R.id.anime_btn:

setBackgroundColorById(R.id.anime_btn);

ft.replace(R.id.fragment_content,new AnimeFragment());

break;

case R.id.variety_btn:

setBackgroundColorById(R.id.variety_btn);

ft.replace(R.id.fragment_content,new VarietyFragment());

break;

default:

break;

}

// 不要忘记提交

ft.commit();

}

}</span></span>

7.电影界面：fragment_movie.xml和MovieFragment.java

[html] view
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<span style="font-family:SimSun;"><span style="font-size:18px;"><?xml version="1.0"encoding="utf-8"?>

<LinearLayoutxmlns:androidLinearLayoutxmlns:android="http://schemas.android.com/apk/res/android"

android:layout_width="match_parent"

android:layout_height="match_parent"

android:background="#FF00FF"

android:orientation="vertical" >

<TextView

android:id="@+id/movie_tv"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:text="@string/movie_view" />

</LinearLayout></span></span>

[java] view
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<span style="font-family:SimSun;"><span style="font-size:18px;">packagecom.example.myandroidswitchbtndemo;

import android.app.Fragment;

importandroid.os.Bundle;

importandroid.view.LayoutInflater;

importandroid.view.View;

importandroid.view.ViewGroup;

public classMovieFragment extends Fragment {

<spanstyle="white-space:pre"> </span>@Override

public View onCreateView(LayoutInflater inflater, ViewGroup container,

Bundle savedInstanceState) {

return inflater.inflate(R.layout.fragment_movie, null);

}

}</span></span>

8.电视剧界面：fragment_tv.xml和TVFragment.java

[html] view
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<span style="font-family:SimSun;"><span style="font-size:18px;"><?xmlversionxmlversion="1.0" encoding="utf-8"?>

<LinearLayoutxmlns:androidLinearLayoutxmlns:android="http://schemas.android.com/apk/res/android"

android:layout_width="match_parent"

android:layout_height="match_parent"

android:background="#00FFFF"

android:orientation="vertical">

<TextView

android:id="@+id/tv_tv"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:text="@string/tv_view"

/>

</LinearLayout></span></span>

[java] view
plain copy

<span style="font-family:SimSun;"><span style="font-size:18px;">packagecom.example.myandroidswitchbtndemo;

importandroid.os.Bundle;

importandroid.app.Fragment;

importandroid.view.LayoutInflater;

importandroid.view.View;

importandroid.view.ViewGroup;

public classTVFragment extends Fragment {

<spanstyle="white-space:pre"> </span>@Override

public View onCreateView(LayoutInflater inflater, ViewGroup container,

Bundle savedInstanceState) {

return inflater.inflate(R.layout.fragment_tv, null);

}

}</span></span>

9.动漫界面：fragment_anime和AnimeFragment.java

[html] view
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<span style="font-family:SimSun;"><span style="font-size:18px;"><?xmlversionxmlversion="1.0" encoding="utf-8"?>

<LinearLayoutxmlns:androidLinearLayoutxmlns:android="http://schemas.android.com/apk/res/android"

android:layout_width="match_parent"

android:layout_height="match_parent"

android:background="#00FF00"

android:orientation="vertical">

<TextView

android:id="@+id/anime_tv"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:text="@string/anime_view"

/>

</LinearLayout></span></span>

[java] view
plain copy

<span style="font-family:SimSun;"><span style="font-size:18px;">packagecom.example.myandroidswitchbtndemo;

importandroid.os.Bundle;

importandroid.annotation.SuppressLint;

importandroid.app.Fragment;

importandroid.view.LayoutInflater;

importandroid.view.View;

importandroid.view.ViewGroup;

@SuppressLint("NewApi")

public classAnimeFragment extends Fragment {

<spanstyle="white-space:pre"> </span>@Override

public View onCreateView(LayoutInflater inflater, ViewGroup container,

Bundle savedInstanceState) {

return inflater.inflate(R.layout.fragment_anime, null);

}

}</span></span>

10.综艺界面：fragment_variety和VarietyFragment

[html] view
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<span style="font-family:SimSun;"><span style="font-size:18px;"><?xmlversionxmlversion="1.0" encoding="utf-8"?>

<LinearLayoutxmlns:androidLinearLayoutxmlns:android="http://schemas.android.com/apk/res/android"

android:layout_width="match_parent"

android:layout_height="match_parent"

android:background="#FFFF00"

android:orientation="vertical">

<TextView

android:id="@+id/variety_tv"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:text="@string/variety_view"/>

</LinearLayout></span></span>

[java] view
plain copy

<span style="font-family:SimSun;"><span style="font-size:18px;">packagecom.example.myandroidswitchbtndemo;

importandroid.os.Bundle;

importandroid.app.Fragment;

importandroid.view.LayoutInflater;

importandroid.view.View;

importandroid.view.ViewGroup;

public classVarietyFragment extends Fragment {

<spanstyle="white-space:pre"> </span>@Override

public View onCreateView(LayoutInflater inflater, ViewGroup container,

Bundle savedInstanceState) {

return inflater.inflate(R.layout.fragment_variety, null);

}

}

</span></span>

上面为代码的具体实现。

源代码下载地址：http://download.csdn.net/detail/a123demi/7524047