备注：代码已传至https://github.com/yanzi1225627/FragmentProject_QQ 欢迎fork，如今来审视这份代码，非常多地方写的不太好,欢迎大家指正。有时间我会继续完好。2015-11-1.
近期重复研究日常经典必用的几个android app，从主界面带来的交互方式入手进行分析，我将其大致分为三类。今天记录第一种方式。即主界面以下有几个tab页。最上端是标题栏。tab页和tab页之间不是通过滑动切换的，而是通过点击切换tab页。
早期这样的架构一直是使用tabhost+activitygroup来使用，随着fragment的出现及google官方也大力推荐使用fragment，后者大有取代前者之势。本文也使用fragment进行搭建，标题中的“经典”指这样的交互经典。非本文的代码框架结构，欢迎大家提出指出不足，帮助完好。文中的fragment部分參考了郭神的博文(链接1 链接2 链接3)。代码也是在郭神代码基础上加入了自己对框架的理解。
再次重申下这样的主界面交互的特点:1,多个tab。不能滑动切换仅仅能点击切换；2，上有标题栏。这样的模式也是眼下app中使用最多的。
如qq、百度云盘、招商银行、微博、支付宝。几个月前支付宝还是能滑动切换的，后来取消了。视图例如以下:
以下本文从底部控制栏、顶部控制栏及中间的内容显示载体fragment三部分叙述。
一、底部控制栏
底部控制栏里每一个控件都不是单一基础控件。上面是图片、以下是文字。右上角是红点，当有更新时红点显示。否则隐藏。另外像qq的右上角还能显示未读消息的个数。我的參考链接里是通过大量的layout一点一点搭出来的，这样的优点是方便控制比較直观，另外是能够利用Linearlayout里的layout_weight这个属性，让底部的这些item均匀分布。缺点是代码上有非常多重复，维护起来不方便。
既然是整理app的通用模板框架，因此我将每一个item视为一个对象，然后将其放在底部就ok了。本代码里仅仅封装了上面是图片以下是文字。右上角的红点么有封装进来。
ImageText.java就作了这样一件事:
package org.yanzi.ui;
import org.yanzi.constant.Constant;
import android.content.Context;
import android.graphics.Color;
import android.util.AttributeSet;
import android.view.LayoutInflater;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.TextView;
import com.example.fragmentproject.R;
public class ImageText extends LinearLayout{
private Context mContext = null;
private ImageView mImageView = null;
private TextView mTextView = null;
private final static int DEFAULT_IMAGE_WIDTH = 64;
private final static int DEFAULT_IMAGE_HEIGHT = 64;
private int CHECKED_COLOR = Color.rgb(29, 118, 199); //选中蓝色
private int UNCHECKED_COLOR = Color.GRAY; //自然灰色
public ImageText(Context context) {
super(context);
// TODO Auto-generated constructor stub
mContext = context;
}
public ImageText(Context context, AttributeSet attrs) {
super(context, attrs);
// TODO Auto-generated constructor stub
mContext = context;
LayoutInflater inflater = (LayoutInflater) mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View parentView = inflater.inflate(R.layout.image_text_layout, this, true);
mImageView = (ImageView)findViewById(R.id.image_iamge_text);
mTextView = (TextView)findViewById(R.id.text_iamge_text);
}
public void setImage(int id){
if(mImageView != null){
mImageView.setImageResource(id);
setImageSize(DEFAULT_IMAGE_WIDTH, DEFAULT_IMAGE_HEIGHT);
}
}
public void setText(String s){
if(mTextView != null){
mTextView.setText(s);
mTextView.setTextColor(UNCHECKED_COLOR);
}
}
@Override
public boolean onInterceptTouchEvent(MotionEvent ev) {
// TODO Auto-generated method stub
return true;
}
private void setImageSize(int w, int h){
if(mImageView != null){
ViewGroup.LayoutParams params = mImageView.getLayoutParams();
params.width = w;
params.height = h;
mImageView.setLayoutParams(params);
}
}
public void setChecked(int itemID){
if(mTextView != null){
mTextView.setTextColor(CHECKED_COLOR);
}
int checkDrawableId = -1;
switch (itemID){
case Constant.BTN_FLAG_MESSAGE:
checkDrawableId = R.drawable.message_selected;
break;
case Constant.BTN_FLAG_CONTACTS:
checkDrawableId = R.drawable.contacts_selected;
break;
case Constant.BTN_FLAG_NEWS:
checkDrawableId = R.drawable.news_selected;
break;
case Constant.BTN_FLAG_SETTING:
checkDrawableId = R.drawable.setting_selected;
break;
default:break;
}
if(mImageView != null){
mImageView.setImageResource(checkDrawableId);
}
}
}
相应的布局:
<?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" >
<ImageView
android:id="@+id/image_iamge_text"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal" />
<TextView
android:id="@+id/text_iamge_text"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal" />
</LinearLayout>代码里用到了Constant.java，这里面放的都是常量：
package org.yanzi.constant;
public class Constant {
//Btn的标识
public static final int BTN_FLAG_MESSAGE = 0x01;
public static final int BTN_FLAG_CONTACTS = 0x01 << 1;
public static final int BTN_FLAG_NEWS = 0x01 << 2;
public static final int BTN_FLAG_SETTING = 0x01 << 3;
//Fragment的标识
public static final String FRAGMENT_FLAG_MESSAGE = "消息";
public static final String FRAGMENT_FLAG_CONTACTS = "联系人";
public static final String FRAGMENT_FLAG_NEWS = "新闻";
public static final String FRAGMENT_FLAG_SETTING = "设置";
public static final String FRAGMENT_FLAG_SIMPLE = "simple";
}
完毕了ImageText之后，以下就是将4个这样的控件放到一个布局里。为了控制方便，我们将底部栏抽象为一个对象BottomControlPanel.java，这样在维护底部栏相关内容时直接找他即可了。BottomControlPanel继承自RelativeLayout，先来看它的布局:
bottom_panel_layout.xml
<?xml version="1.0" encoding="utf-8"?>
<org.yanzi.ui.BottomControlPanel xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="60dp"
android:layout_alignParentBottom="true"
android:gravity="center_vertical"
android:paddingLeft="20dp"
android:paddingRight="20dp" >
<org.yanzi.ui.ImageText
android:id="@+id/btn_message"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true" />
<org.yanzi.ui.ImageText
android:id="@+id/btn_contacts"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_toRightOf="@id/btn_message" />
<org.yanzi.ui.ImageText
android:id="@+id/btn_news"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_toRightOf="@id/btn_contacts" />
<org.yanzi.ui.ImageText
android:id="@+id/btn_setting"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true" />
</org.yanzi.ui.BottomControlPanel>BottomControlPanel.java
在onFinishInflate()函数里实例化里面的子元素，在initBottomPanel()里设置每一个孩子的图片和文字、监听.onLayout()里对中间的2个孩子的位置进行调整。使其均匀分布，见我的前文。package org.yanzi.ui; import java.util.ArrayList; import java.util.List; import org.yanzi.constant.Constant; import android.content.Context; import android.graphics.Color; import android.util.AttributeSet; import android.util.Log; import android.view.View; import android.widget.RelativeLayout; import com.example.fragmentproject.R; public class BottomControlPanel extends RelativeLayout implements View.OnClickListener { private Context mContext; private ImageText mMsgBtn = null; private ImageText mContactsBtn = null; private ImageText mNewsBtn = null; private ImageText mSettingBtn = null; private int DEFALUT_BACKGROUND_COLOR = Color.rgb(243, 243, 243); //Color.rgb(192, 192, 192) private BottomPanelCallback mBottomCallback = null; private List<ImageText> viewList = new ArrayList<ImageText>(); public interface BottomPanelCallback{ public void onBottomPanelClick(int itemId); } public BottomControlPanel(Context context, AttributeSet attrs) { super(context, attrs); // TODO Auto-generated constructor stub } @Override protected void onFinishInflate() { // TODO Auto-generated method stub mMsgBtn = (ImageText)findViewById(R.id.btn_message); mContactsBtn = (ImageText)findViewById(R.id.btn_contacts); mNewsBtn = (ImageText)findViewById(R.id.btn_news); mSettingBtn = (ImageText)findViewById(R.id.btn_setting); setBackgroundColor(DEFALUT_BACKGROUND_COLOR); viewList.add(mMsgBtn); viewList.add(mContactsBtn); viewList.add(mNewsBtn); viewList.add(mSettingBtn); } public void initBottomPanel(){ if(mMsgBtn != null){ mMsgBtn.setImage(R.drawable.message_unselected); mMsgBtn.setText("消息"); } if(mContactsBtn != null){ mContactsBtn.setImage(R.drawable.contacts_unselected); mContactsBtn.setText("联系人"); } if(mNewsBtn != null){ mNewsBtn.setImage(R.drawable.news_unselected); mNewsBtn.setText("新闻"); } if(mSettingBtn != null){ mSettingBtn.setImage(R.drawable.setting_unselected); mSettingBtn.setText("设置"); } setBtnListener(); } private void setBtnListener(){ int num = this.getChildCount(); for(int i = 0; i < num; i++){ View v = getChildAt(i); if(v != null){ v.setOnClickListener(this); } } } public void setBottomCallback(BottomPanelCallback bottomCallback){ mBottomCallback = bottomCallback; } @Override public void onClick(View v) { // TODO Auto-generated method stub initBottomPanel(); int index = -1; switch(v.getId()){ case R.id.btn_message: index = Constant.BTN_FLAG_MESSAGE; mMsgBtn.setChecked(Constant.BTN_FLAG_MESSAGE); break; case R.id.btn_contacts: index = Constant.BTN_FLAG_CONTACTS; mContactsBtn.setChecked(Constant.BTN_FLAG_CONTACTS); break; case R.id.btn_news: index = Constant.BTN_FLAG_NEWS; mNewsBtn.setChecked(Constant.BTN_FLAG_NEWS); break; case R.id.btn_setting: index = Constant.BTN_FLAG_SETTING; mSettingBtn.setChecked(Constant.BTN_FLAG_SETTING); break; default:break; } if(mBottomCallback != null){ mBottomCallback.onBottomPanelClick(index); } } public void defaultBtnChecked(){ if(mMsgBtn != null){ mMsgBtn.setChecked(Constant.BTN_FLAG_MESSAGE); } } @Override protected void onLayout(boolean changed, int left, int top, int right, int bottom) { // TODO Auto-generated method stub super.onLayout(changed, left, top, right, bottom); layoutItems(left, top, right, bottom); } /**最左边和最右边的view由母布局的padding进行控制位置。
这里需对第2、3个view的位置又一次设置 * @param left * @param top * @param right * @param bottom */ private void layoutItems(int left, int top, int right, int bottom){ int n = getChildCount(); if(n == 0){ return; } int paddingLeft = getPaddingLeft(); int paddingRight = getPaddingRight(); Log.i("yanguoqi", "paddingLeft = " + paddingLeft + " paddingRight = " + paddingRight); int width = right - left; int height = bottom - top; Log.i("yanguoqi", "width = " + width + " height = " + height); int allViewWidth = 0; for(int i = 0; i< n; i++){ View v = getChildAt(i); Log.i("yanguoqi", "v.getWidth() = " + v.getWidth()); allViewWidth += v.getWidth(); } int blankWidth = (width - allViewWidth - paddingLeft - paddingRight) / (n - 1); Log.i("yanguoqi", "blankV = " + blankWidth ); LayoutParams params1 = (LayoutParams) viewList.get(1).getLayoutParams(); params1.leftMargin = blankWidth; viewList.get(1).setLayoutParams(params1); LayoutParams params2 = (LayoutParams) viewList.get(2).getLayoutParams(); params2.leftMargin = blankWidth; viewList.get(2).setLayoutParams(params2); } }
这个BottomControlPanel实现了View.OnClickListener接口，在onClick()里通过id来推断用户点击了哪一个孩子。
推断出来后须要做两件事。一是对这个被点击的对象进行处理。如字体颜色、图片资源的变化，右上角小红点的隐藏等等。还有一方面，BottomControlPanel要告诉将来它的主人。也就是Activity究竟是点了哪个，通知Activity去切换fragment。
能够看到，activity相似个总控中心，BottomControlPanel管理属于它的ImageText，同一时候上报Activity。Activity知道消息后再切换fragment，每一个fragment都有自己的事务逻辑。
这里定义了
public interface BottomPanelCallback{
public void onBottomPanelClick(int itemId);
}这个接口，通过传递Id来通知Activity。defaultBtnChecked()函数是apk初次打开后，默认切换到第一个消息fragment上。
这里有个地方须要注意。就是尽管ImageText和BottomControlPanel都是自己定义控件，但两者在方式上是有差别的。在ImageText的构造函数里通过inflater将布局载入进来。它相应的布局是个普通的布局。而BottomControlPanel相应的布局文件中，直接使用了定义的BottomControlPanel，在onFinishInflate函数里实例化孩子View。前者是inflate之后实例化的。在使用ImageText到一个新的母布局时是通过<org.yanzi.ui.ImageText />这样的方式进行的，那么使用BottomControlPanel有何差别，请见下文介绍Activity的布局时。
二、顶部控制栏
有了底部控制栏，顶部控制栏就能够如法炮制了。这里先交代几句。尽管Android3.0 后Google推出的有ActionBar来做顶部导航栏，參见郭神的这篇博文。但我发现。本文最前面贴图的几款应用应该都没有使用ActionBar。由于它不够灵活。
ActionBar使用起来什么样，大家看看微信就知道了，那个的顶部控制栏就是ActionBar做的，这个应该没跑。
通过观察。顶部控制栏除了标题居中外，在右上角一般会再放一个button。
不是ImageView就是TextView，这里我为了方便放的是两个TextView，右側的button效果能够再TextView上弄个背景来实现。
HeadControlPanel.java
package org.yanzi.ui;
import org.yanzi.constant.Constant;
import com.example.fragmentproject.R;
import android.content.Context;
import android.graphics.Color;
import android.util.AttributeSet;
import android.widget.RelativeLayout;
import android.widget.TextView;
public class HeadControlPanel extends RelativeLayout {
private Context mContext;
private TextView mMidleTitle;
private TextView mRightTitle;
private static final float middle_title_size = 20f;
private static final float right_title_size = 17f;
private static final int default_background_color = Color.rgb(23, 124, 202);
public HeadControlPanel(Context context, AttributeSet attrs) {
super(context, attrs);
// TODO Auto-generated constructor stub
}
@Override
protected void onFinishInflate() {
// TODO Auto-generated method stub
mMidleTitle = (TextView)findViewById(R.id.midle_title);
mRightTitle = (TextView)findViewById(R.id.right_title);
setBackgroundColor(default_background_color);
}
public void initHeadPanel(){
if(mMidleTitle != null){
setMiddleTitle(Constant.FRAGMENT_FLAG_MESSAGE);
}
}
public void setMiddleTitle(String s){
mMidleTitle.setText(s);
mMidleTitle.setTextSize(middle_title_size);
}
}
布局文件head_panel_layout.xml
<?xml version="1.0" encoding="utf-8"?
> <org.yanzi.ui.HeadControlPanel xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="50dp" android:layout_alignParentTop="true"> <TextView android:id="@+id/midle_title" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_centerInParent="true" android:textColor="@android:color/white"/> <TextView android:id="@+id/right_title" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_alignParentRight="true" android:textColor="@android:color/white"/> </org.yanzi.ui.HeadControlPanel>
三、总控中心Activity和Fragment
先交代下Fragment的使用大致分两种，一种是将Fragment作为一个View写死在布局中，布局里使用android:name来告诉它相应的是哪个实体Fragment。这样的加入fragment的方式不能delete和replace掉。
还有一种是通过获得activity的fragmentmanager和fragmentTransaction和进行动态的加入。
这样的方式更加灵活。一般使用此种方法。
先看Activity的布局activity_main.xml:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/root_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="org.yanzi.fragmentproject.MainActivity" >
<include
android:id="@+id/bottom_layout"
layout="@layout/bottom_panel_layout" />
<View
android:layout_width="match_parent"
android:layout_height="1dip"
android:layout_above="@id/bottom_layout"
android:background="#FFE7E7E7" />
<include
android:id="@+id/head_layout"
layout="@layout/head_panel_layout" />
<View
android:layout_width="match_parent"
android:layout_height="1dip"
android:layout_below="@id/head_layout"
android:background="#FFE7E7E7" />
<FrameLayout
android:id="@+id/fragment_content"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="@id/head_layout"
android:layout_above="@id/bottom_layout" >
</FrameLayout>
</RelativeLayout>注意看这里是通过include的方式把刚才自己定义的上下panel加过来，而不能直接用<org.yanzi.ui.BottomControlPanel />这样的方式直接载入。当然假设也模仿ImageText的构造方式。也是能够这样用的。关于include方式的使用有几个注意事项，就是最好让它的母布局是RelativeLayout，否则的话非常难控制include进来的布局的位置。
另外。include布局的位置一定要写在include之前。如底部面板在最底部。android:layout_alignParentBottom="true"这句话是在bottom_panel_layout.xml里写的，假设写在activity_main.xml里就是无效的，这着实是个蛋疼的问题。
再就是include后设置的id会覆盖掉曾经的。所以这里仅仅在include的时候设置id。
当中的两个View是切割线。总体是依照底部栏、上部栏、中间Fragment的容器来放置的。
在放Fragment的时候须要注意。究竟是否要将顶部控制栏放到各自的fragment里合适还是放到Activity里合适要看详细情况，假设顶部栏里多是显示标题这样的功能或少量的点击事件，应该放到Activity里。即顶部栏的事务逻辑和当前fragment的事务逻辑耦合的不是非常紧。
举个样例。比方微信的顶部栏。无论你处在哪个Tab页(聊天、发现、通讯录)，点击顶部栏里的button都呈现出相同的内容。但反过来讲，假设顶部栏里的事务逻辑和fragment耦合非常紧，即在不同的fragment。顶部栏呈现的内容都不一样，且点击后处理的事务也和当前fragment紧密联系一起，那就应该一个fragment配套一个顶部栏，方便控制。
本文是将两者分开的。
所以让fragment的容器在顶部栏之下，底部栏之上。不这样写的话，就会遮挡。
<FrameLayout
android:id="@+id/fragment_content"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="@id/head_layout"
android:layout_above="@id/bottom_layout" >
</FrameLayout>
MainActivity.java代码：
package org.yanzi.activity;
import org.yanzi.constant.Constant;
import org.yanzi.fragment.BaseFragment;
import org.yanzi.fragment.ContactsFragment;
import org.yanzi.fragment.MessageFragment;
import org.yanzi.fragment.NewsFragment;
import org.yanzi.fragment.SettingFragment;
import org.yanzi.ui.BottomControlPanel;
import org.yanzi.ui.BottomControlPanel.BottomPanelCallback;
import org.yanzi.ui.HeadControlPanel;
import android.app.Activity;
import android.app.Fragment;
import android.app.FragmentManager;
import android.app.FragmentTransaction;
import android.os.Bundle;
import android.text.TextUtils;
import android.util.Log;
import android.view.Menu;
import android.widget.Toast;
import com.example.fragmentproject.R;
public class MainActivity extends Activity implements BottomPanelCallback {
BottomControlPanel bottomPanel = null;
HeadControlPanel headPanel = null;
private FragmentManager fragmentManager = null;
private FragmentTransaction fragmentTransaction = null;
/* private MessageFragment messageFragment;
private ContactsFragment contactsFragment;
private NewsFragment newsFragment;
private SettingFragment settingFragment;*/
public static String currFragTag = "";
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initUI();
fragmentManager = getFragmentManager();
setDefaultFirstFragment(Constant.FRAGMENT_FLAG_MESSAGE);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
private void initUI(){
bottomPanel = (BottomControlPanel)findViewById(R.id.bottom_layout);
if(bottomPanel != null){
bottomPanel.initBottomPanel();
bottomPanel.setBottomCallback(this);
}
headPanel = (HeadControlPanel)findViewById(R.id.head_layout);
if(headPanel != null){
headPanel.initHeadPanel();
}
}
/* 处理BottomControlPanel的回调
* @see org.yanzi.ui.BottomControlPanel.BottomPanelCallback#onBottomPanelClick(int)
*/
@Override
public void onBottomPanelClick(int itemId) {
// TODO Auto-generated method stub
String tag = "";
if((itemId & Constant.BTN_FLAG_MESSAGE) != 0){
tag = Constant.FRAGMENT_FLAG_MESSAGE;
}else if((itemId & Constant.BTN_FLAG_CONTACTS) != 0){
tag = Constant.FRAGMENT_FLAG_CONTACTS;
}else if((itemId & Constant.BTN_FLAG_NEWS) != 0){
tag = Constant.FRAGMENT_FLAG_NEWS;
}else if((itemId & Constant.BTN_FLAG_SETTING) != 0){
tag = Constant.FRAGMENT_FLAG_SETTING;
}
setTabSelection(tag); //切换Fragment
headPanel.setMiddleTitle(tag);//切换标题
}
private void setDefaultFirstFragment(String tag){
Log.i("yan", "setDefaultFirstFragment enter... currFragTag = " + currFragTag);
setTabSelection(tag);
bottomPanel.defaultBtnChecked();
Log.i("yan", "setDefaultFirstFragment exit...");
}
private void commitTransactions(String tag){
if (fragmentTransaction != null && !fragmentTransaction.isEmpty()) {
fragmentTransaction.commit();
currFragTag = tag;
fragmentTransaction = null;
}
}
private FragmentTransaction ensureTransaction( ){
if(fragmentTransaction == null){
fragmentTransaction = fragmentManager.beginTransaction();
fragmentTransaction
.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_FADE);
}
return fragmentTransaction;
}
private void attachFragment(int layout, Fragment f, String tag){
if(f != null){
if(f.isDetached()){
ensureTransaction();
fragmentTransaction.attach(f);
}else if(!f.isAdded()){
ensureTransaction();
fragmentTransaction.add(layout, f, tag);
}
}
}
private Fragment getFragment(String tag){
Fragment f = fragmentManager.findFragmentByTag(tag);
if(f == null){
Toast.makeText(getApplicationContext(), "fragment = null tag = " + tag, Toast.LENGTH_SHORT).show();
f = BaseFragment.newInstance(getApplicationContext(), tag);
}
return f;
}
private void detachFragment(Fragment f){
if(f != null && !f.isDetached()){
ensureTransaction();
fragmentTransaction.detach(f);
}
}
/**切换fragment
* @param tag
*/
private void switchFragment(String tag){
if(TextUtils.equals(tag, currFragTag)){
return;
}
//把上一个fragment detach掉
if(currFragTag != null && !currFragTag.equals("")){
detachFragment(getFragment(currFragTag));
}
attachFragment(R.id.fragment_content, getFragment(tag), tag);
commitTransactions( tag);
}
/**设置选中的Tag
* @param tag
*/
public void setTabSelection(String tag) {
// 开启一个Fragment事务
fragmentTransaction = fragmentManager.beginTransaction();
/* if(TextUtils.equals(tag, Constant.FRAGMENT_FLAG_MESSAGE)){
if (messageFragment == null) {
messageFragment = new MessageFragment();
}
}else if(TextUtils.equals(tag, Constant.FRAGMENT_FLAG_CONTACTS)){
if (contactsFragment == null) {
contactsFragment = new ContactsFragment();
}
}else if(TextUtils.equals(tag, Constant.FRAGMENT_FLAG_NEWS)){
if (newsFragment == null) {
newsFragment = new NewsFragment();
}
}else if(TextUtils.equals(tag,Constant.FRAGMENT_FLAG_SETTING)){
if (settingFragment == null) {
settingFragment = new SettingFragment();
}
}else if(TextUtils.equals(tag, Constant.FRAGMENT_FLAG_SIMPLE)){
if (simpleFragment == null) {
simpleFragment = new SimpleFragment();
}
}*/
switchFragment(tag);
}
@Override
protected void onStop() {
// TODO Auto-generated method stub
super.onStop();
currFragTag = "";
}
@Override
protected void onSaveInstanceState(Bundle outState) {
// TODO Auto-generated method stub
}
}
注意这块我作了修改。不须要申明
/* private MessageFragment messageFragment;
private ContactsFragment contactsFragment;
private NewsFragment newsFragment;
private SettingFragment settingFragment;*/
这些内容，由于Fragment的生成是通过BaseFragment.newInstance()来生成的。传进去Tag生成相应的Fragment。全部的Fragment。ContactsFragment、MessageFragment、NewsFragment、SettingFragment都继承自BaseFragment。通过BaseFragment里的newInstance()接口进行实例化相应的fragment。
优点是方便管理。缺点么也有，由于java继承继承一个类，不能同一时候继承两个类。
所以如ListFragment这些。就没法同一时候继承了。只是好在有listview这些。也妨碍不了我们做到相同的效果。
Activity里事件的入口是在onBottomPanelClick()监听点击了谁，然后：
setTabSelection(tag); //切换Fragment
headPanel.setMiddleTitle(tag);//切换标题
先切换Fragment再切换顶部栏的标题。setTabSelection()里直接调switchFragment(),在switchFragment函数里先推断标签是否一样，一样则意外着无需切换，否则的话就先把当前Fragment找到然后detach掉。之后进到attachFragment()函数里。在这里，先推断这个fragment是不是被detach掉的，假设是的话意味着之前曾被add过，所以仅仅需attach就ok了。
否则的话，意味着这是第一次。进行add.这里记录下Fragment的声明周期:
MessageFragment正常打开：
Line 155: 01-04 11:50:46.688 E/MessageFragment( 2546): onAttach-----
Line 159: 01-04 11:50:46.688 E/MessageFragment( 2546): onCreate------
Line 161: 01-04 11:50:46.693 D/MessageFragment( 2546): onCreateView---->
Line 165: 01-04 11:50:46.694 E/MessageFragment( 2546): onActivityCreated-------
Line 169: 01-04 11:50:46.694 E/MessageFragment( 2546): onStart----->
Line 173: 01-04 11:50:46.694 E/MessageFragment( 2546): onresume---->
返回键退出：
Line 183: 01-04 11:52:26.506 E/MessageFragment( 2546): onpause
Line 259: 01-04 11:52:27.131 E/MessageFragment( 2546): onStop
Line 263: 01-04 11:52:27.132 E/MessageFragment( 2546): ondestoryView
Line 269: 01-04 11:52:27.134 E/MessageFragment( 2546): ondestory
Line 271: 01-04 11:52:27.135 D/MessageFragment( 2546): onDetach------
按home按键退出:
Line 97: 01-05 05:06:15.659 E/MessageFragment(18835): onpause
Line 215: 01-05 05:06:16.292 E/MessageFragment(18835): onStop
再次打开：
Line 81: 01-05 05:07:02.408 E/MessageFragment(18835): onStart----->
Line 85: 01-05 05:07:02.408 E/MessageFragment(18835): onresume---->
通过detach的方式切换至其它Fragment：
Line 69: 01-04 11:53:33.381 E/MessageFragment( 2546): onpause
Line 73: 01-04 11:53:33.382 E/MessageFragment( 2546): onStop
Line 77: 01-04 11:53:33.382 E/MessageFragment( 2546): ondestoryView
再次切换过来:
Line 55: 01-04 11:54:59.462 D/MessageFragment( 2546): onCreateView---->
Line 59: 01-04 11:54:59.463 E/MessageFragment( 2546): onActivityCreated-------
Line 63: 01-04 11:54:59.463 E/MessageFragment( 2546): onStart----->
Line 67: 01-04 11:54:59.464 E/MessageFragment( 2546): onresume---->
四、适配器和MessageBean
本来要连数据库的。时间原因用个简单的MessageBean取代了。
一个消息分联系人头像、名字、消息正文和时间四部分组成，封装到一个MessageBean里。
MessageBean.java
package org.yanzi.bean;
public class MessageBean {
private int PhotoDrawableId;
private String MessageName;
private String MessageContent;
private String MessageTime;
public MessageBean(){
}
public MessageBean(int photoDrawableId, String messageName,
String messageContent, String messageTime) {
super();
PhotoDrawableId = photoDrawableId;
MessageName = messageName;
MessageContent = messageContent;
MessageTime = messageTime;
}
public int getPhotoDrawableId() {
return PhotoDrawableId;
}
public void setPhotoDrawableId(int mPhotoDrawableId) {
this.PhotoDrawableId = mPhotoDrawableId;
}
public String getMessageName() {
return MessageName;
}
public void setMessageName(String messageName) {
MessageName = messageName;
}
public String getMessageContent() {
return MessageContent;
}
public void setMessageContent(String messageContent) {
MessageContent = messageContent;
}
public String getMessageTime() {
return MessageTime;
}
public void setMessageTime(String messageTime) {
MessageTime = messageTime;
}
@Override
public String toString() {
return "MessageBean [mPhotoDrawableId=" + PhotoDrawableId
+ ", MessageName=" + MessageName + ", MessageContent="
+ MessageContent + ", MessageTime=" + MessageTime + "]";
}
}
package org.yanzi.fragment.adapter;
import java.util.List;
import org.yanzi.bean.MessageBean;
import com.example.fragmentproject.R;
import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.TextView;
public class MessageAdapter extends BaseAdapter {
private List<MessageBean> mListMsgBean = null;
private Context mContext;
private LayoutInflater mInflater;
public MessageAdapter(List<MessageBean> listMsgBean, Context context){
mListMsgBean = listMsgBean;
mContext = context;
mInflater = LayoutInflater.from(mContext);
}
@Override
public int getCount() {
// TODO Auto-generated method stub
return mListMsgBean.size();
}
@Override
public Object getItem(int position) {
// TODO Auto-generated method stub
return mListMsgBean.get(position);
}
@Override
public long getItemId(int position) {
// TODO Auto-generated method stub
return position;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
// TODO Auto-generated method stub
View v = mInflater.inflate(R.layout.message_item_layout, null);
ImageView imageView = (ImageView) v.findViewById(R.id.img_msg_item);
imageView.setImageResource(mListMsgBean.get(position).getPhotoDrawableId());
TextView nameMsg = (TextView)v.findViewById(R.id.name_msg_item);
nameMsg.setText(mListMsgBean.get(position).getMessageName());
TextView contentMsg = (TextView)v.findViewById(R.id.content_msg_item);
contentMsg.setText(mListMsgBean.get(position).getMessageContent());
TextView timeMsg = (TextView)v.findViewById(R.id.time_msg_item);
timeMsg.setText(mListMsgBean.get(position).getMessageTime());
return v;
}
}
最后是MessageFragment里通过对listview设置适配器。将MessageBean作为信息的提供者也填充到适配器里。
MessageFragment.java代码：
最后来看下效果吧，仅仅有MessageFragment填充了数据：package org.yanzi.fragment; import java.util.ArrayList; import java.util.List; import org.yanzi.activity.MainActivity; import org.yanzi.bean.MessageBean; import org.yanzi.constant.Constant; import org.yanzi.fragment.adapter.MessageAdapter; import android.app.Activity; import android.os.Bundle; import android.util.Log; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.AdapterView; import android.widget.Toast; import android.widget.AdapterView.OnItemClickListener; import android.widget.ListView; import com.example.fragmentproject.R; public class MessageFragment extends BaseFragment { private static final String TAG = "MessageFragment"; private MainActivity mMainActivity ; private ListView mListView; private MessageAdapter mMsgAdapter; private List<MessageBean> mMsgBean = new ArrayList<MessageBean>(); public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { View messageLayout = inflater.inflate(R.layout.message_layout, container, false); Log.d(TAG, "onCreateView---->"); mMainActivity = (MainActivity) getActivity(); mFragmentManager = getActivity().getFragmentManager(); mListView = (ListView)messageLayout.findViewById(R.id.listview_message); mMsgAdapter = new MessageAdapter(mMsgBean, mMainActivity); mListView.setAdapter(mMsgAdapter); mListView.setOnItemClickListener(new OnItemClickListener() { @Override public void onItemClick(AdapterView<?> parent, View view, int position, long id) { // TODO Auto-generated method stub Toast.makeText(mMainActivity, mMsgBean.get(position).toString(), Toast.LENGTH_SHORT).show(); } }); return messageLayout; } @Override public void onAttach(Activity activity) { // TODO Auto-generated method stub super.onAttach(activity); Log.e(TAG, "onAttach-----"); } @Override public void onCreate(Bundle savedInstanceState) { // TODO Auto-generated method stub super.onCreate(savedInstanceState); Log.e(TAG, "onCreate------"); mMsgBean.add(new MessageBean(R.drawable.ic_photo_1, "张三", "吃饭没?", "昨天")); mMsgBean.add(new MessageBean(R.drawable.ic_photo_2, "李四", "哈哈", "昨天")); mMsgBean.add(new MessageBean(R.drawable.ic_photo_3, "小明", "吃饭没?", "昨天")); mMsgBean.add(new MessageBean(R.drawable.ic_photo_4, "王五", "吃饭没?", "昨天")); mMsgBean.add(new MessageBean(R.drawable.ic_photo_5, "Jack", "吃饭没?", "昨天")); mMsgBean.add(new MessageBean(R.drawable.ic_photo_6, "Jone", "吃饭没?", "昨天")); mMsgBean.add(new MessageBean(R.drawable.ic_photo_7, "Jone", "吃饭没?", "昨天")); mMsgBean.add(new MessageBean(R.drawable.ic_photo_8, "Jone", "吃饭没?
", "昨天")); mMsgBean.add(new MessageBean(R.drawable.ic_photo_9, "Jone", "吃饭没?", "昨天")); } @Override public void onActivityCreated(Bundle savedInstanceState) { // TODO Auto-generated method stub super.onActivityCreated(savedInstanceState); Log.e(TAG, "onActivityCreated-------"); } @Override public void onStart() { // TODO Auto-generated method stub super.onStart(); Log.e(TAG, "onStart----->"); } @Override public void onResume() { // TODO Auto-generated method stub super.onResume(); Log.e(TAG, "onresume---->"); MainActivity.currFragTag = Constant.FRAGMENT_FLAG_MESSAGE; } @Override public void onPause() { // TODO Auto-generated method stub super.onPause(); Log.e(TAG, "onpause"); } @Override public void onStop() { // TODO Auto-generated method stub super.onStop(); Log.e(TAG, "onStop"); } @Override public void onDestroyView() { // TODO Auto-generated method stub super.onDestroyView(); Log.e(TAG, "ondestoryView"); } @Override public void onDestroy() { // TODO Auto-generated method stub super.onDestroy(); Log.e(TAG, "ondestory"); } @Override public void onDetach() { // TODO Auto-generated method stub super.onDetach(); Log.d(TAG, "onDetach------"); } }
横屏情况下:
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