android 项目学习随笔三（Fragment ）

Posted 2020-08-17 ecollab

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1、在主页面（activity引用Fragment ）的布局文件中定义FrameLayout ，加载Fragment

</FrameLayout>

2、初始化Fragment

private void initFragment() {
// Fragment管理器
FragmentManager fm = getSupportFragmentManager();
FragmentTransaction transaction = fm.beginTransaction();// 开始事务
// 将帧布局替换为对应的Fragment
transaction
.replace(R.id.fl_content, new ContentFragment(), TAG_CONTENT);
transaction.replace(R.id.fl_left_menu, new LeftMenuFragment(),
TAG_LEFT_MENU);
transaction.commit();// 提交事务
// fm.findFragmentByTag(TAG_CONTENT);
}

3、定义Fragment基类

public abstract class BaseFragment extends Fragment {

    public Activity mActivity;

    // Fragment被创建
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        mActivity = getActivity();// 获取所在的activity对象
    }

    // 初始化Fragment布局
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {
        View view = initView();
        return view;
    }

    // activity创建结束
    @Override
    public void onActivityCreated(Bundle savedInstanceState) {
        super.onActivityCreated(savedInstanceState);
        initData();
    }

    /**
     * 初始化布局, 子类必须实现
     */
    public abstract View initView();

    /**
     * 初始化数据, 子类可以不实现
     */
    public void initData() {

    }
}

View Code

4、定义下方菜单

<?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" >

    <android.support.v4.view.ViewPager
        android:id="@+id/vp_content"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_weight="1" />

    <RadioGroup
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="@drawable/bottom_tab_bg"
        android:gravity="center"
        android:orientation="horizontal" >

        <RadioButton
            android:id="@+id/rb_home"
            style="@style/BottomTabStyle"
            android:drawableTop="@drawable/btn_home_selector"
            android:checked="true"
            android:text="首页" />

        <RadioButton
            android:id="@+id/rb_news"
            style="@style/BottomTabStyle"
            android:drawableTop="@drawable/btn_news_selector"
            android:text="新闻中心" />

        <RadioButton
            android:id="@+id/rb_smart"
            style="@style/BottomTabStyle"
            android:drawableTop="@drawable/btn_smart_selector"
            android:text="智慧服务" />

        <RadioButton
            android:id="@+id/rb_gov"
            style="@style/BottomTabStyle"
            android:drawableTop="@drawable/btn_gov_selector"
            android:text="政务" />

        <RadioButton
            android:id="@+id/rb_setting"
            style="@style/BottomTabStyle"
            android:drawableTop="@drawable/btn_setting_selector"
            android:text="设置" />
    </RadioGroup>

</LinearLayout>

布局文件

<resources>

    <!--
        Base application theme, dependent on API level. This theme is replaced
        by AppBaseTheme from res/values-vXX/styles.xml on newer devices.


    -->
    <style name="AppBaseTheme" parent="android:Theme.Light">
        <!--
            Theme customizations available in newer API levels can go in
            res/values-vXX/styles.xml, while customizations related to
            backward-compatibility can go here.


        -->
    </style>

    <!-- Application theme. -->
    <style name="AppTheme" parent="AppBaseTheme">
        <!-- All customizations that are NOT specific to a particular API-level can go here. -->
    </style>

    <style name="BottomTabStyle">
        <item name="android:layout_width">wrap_content</item>
        <item name="android:layout_height">wrap_content</item>
        <item name="android:layout_weight">1</item>
        <item name="android:button">@null</item>
        <item name="android:gravity">center</item>
        <item name="android:padding">5dp</item>
        <item name="android:drawablePadding">3dp</item>
        <item name="android:textColor">@color/txt_bottom_tab_selector</item>
    </style>

</resources>

样式文件

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

    <item android:drawable="@drawable/home_press" android:state_checked="true"></item>
    <item android:drawable="@drawable/home"></item>

</selector>

selector

5、定义Fragment

利用XUtils findViewById

ViewUtils使用方法

完全注解方式就可以进行UI绑定和事件绑定。
无需findViewById和setClickListener等。
// xUtils的view注解要求必须提供id，以使代码混淆不受影响。
@ViewInject(R.id.textView)
TextView textView;

//@ViewInject(vale=R.id.textView, parentId=R.id.parentView)
//TextView textView;

@ResInject(id = R.string.label, type = ResType.String)
private String label;

// 取消了之前使用方法名绑定事件的方式，使用id绑定不受混淆影响
// 支持绑定多个id @OnClick({R.id.id1, R.id.id2, R.id.id3})
// or @OnClick(value={R.id.id1, R.id.id2, R.id.id3}, parentId={R.id.pid1, R.id.pid2, R.id.pid3})
// 更多事件支持参见ViewCommonEventListener类和包com.lidroid.xutils.view.annotation.event。
@OnClick(R.id.test_button)
public void testButtonClick(View v) { // 方法签名必须和接口中的要求一致
    ...
}
...
//在Activity中注入：
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    ViewUtils.inject(this); //注入view和事件
    ...
    textView.setText("some text...");
    ...
}
//在Fragment中注入：
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    View view = inflater.inflate(R.layout.bitmap_fragment, container, false); // 加载fragment布局
    ViewUtils.inject(this, view); //注入view和事件
    ...
}
//在PreferenceFragment中注入：
public void onActivityCreated(Bundle savedInstanceState) {
    super.onActivityCreated(savedInstanceState);
    ViewUtils.inject(this, getPreferenceScreen()); //注入view和事件
    ...
}
// 其他重载
// inject(View view);
// inject(Activity activity)
// inject(PreferenceActivity preferenceActivity)
// inject(Object handler, View view)
// inject(Object handler, Activity activity)
// inject(Object handler, PreferenceGroup preferenceGroup)
// inject(Object handler, PreferenceActivity preferenceActivity)

xutils

public class ContentFragment extends BaseFragment {

    @ViewInject(R.id.vp_content)
    private ViewPager mViewPager;

    private ArrayList<BasePager> mPagers;

    @Override
    public View initView() {
        View view = View.inflate(mActivity, R.layout.fragment_content, null);
        ViewUtils.inject(this, view); // 注入view和事件
        // mViewPager = (ViewPager) view.findViewById(R.id.vp_content);
        return view;
    }

    @Override
    public void initData() {
        // 初始化5个标签页面
        mPagers = new ArrayList<BasePager>();
        mPagers.add(new HomePager(mActivity));
        mPagers.add(new NewsCenterPager(mActivity));
        mPagers.add(new SmartServicePager(mActivity));
        mPagers.add(new GovAffairsPager(mActivity));
        mPagers.add(new SettingPager(mActivity));

        mViewPager.setAdapter(new ContentAdapter());
    }

    class ContentAdapter extends PagerAdapter {

        @Override
        public int getCount() {
            return mPagers.size();
        }

        @Override
        public boolean isViewFromObject(View view, Object object) {
            return view == object;
        }

        @Override
        public Object instantiateItem(ViewGroup container, int position) {
            BasePager pager = mPagers.get(position);
            container.addView(pager.mRootView);// 将页面布局添加到容器中
            pager.initData();//初始化数据
            return pager.mRootView;
        }

        @Override
        public void destroyItem(ViewGroup container, int position, Object object) {
            container.removeView((View) object);
        }

    }

}

ContentFragment

6、定义ViewPager页面

<?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" >

    <include layout="@layout/title_bar" />

    <FrameLayout
        android:id="@+id/fl_content"
        android:layout_width="match_parent"
        android:layout_height="match_parent" >
    </FrameLayout>

</LinearLayout>

layout/base_pager.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="wrap_content"
    android:background="@drawable/title_red_bg" >

    <TextView
        android:id="@+id/tv_title"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerHorizontal="true"
        android:layout_centerVertical="true"
        android:text="标题"
        android:textColor="#fff"
        android:textSize="22sp" />

    <ImageButton
        android:id="@+id/btn_menu"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerVertical="true"
        android:layout_marginLeft="10dp"
        android:background="@null"
        android:src="@drawable/img_menu" />

</RelativeLayout>

layout/title_bar.xml

public abstract class BasePager {

    public Activity mActivity;

    public View mRootView;

    public TextView tvTitle;
    public ImageButton btnMenu;
    public FrameLayout flContent;

    public BasePager(Activity activity) {
        mActivity = activity;
        initView();
    }

    /**
     * 初始化布局
     */
    public void initView() {
        mRootView = View.inflate(mActivity, R.layout.base_pager, null);
        tvTitle = (TextView) mRootView.findViewById(R.id.tv_title);
        btnMenu = (ImageButton) mRootView.findViewById(R.id.btn_menu);
        flContent = (FrameLayout) mRootView.findViewById(R.id.fl_content);
    }

    /**
     * 初始化数据
     */
    public abstract void initData();
}

BasePager

public class NewsCenterPager extends BasePager {

    public NewsCenterPager(Activity activity) {
        super(activity);
    }

    @Override
    public void initData() {
        tvTitle.setText("新闻");

        TextView view = new TextView(mActivity);
        view.setText("新闻中心");
        view.setTextColor(Color.RED);
        view.setTextSize(22);
        view.setGravity(Gravity.CENTER);

        flContent.addView(view);
    }

}

NewsCenterPager

public class SettingPager extends BasePager {

    public SettingPager(Activity activity) {
        super(activity);
    }

    @Override
    public void initData() {
        tvTitle.setText("设置");

        TextView view = new TextView(mActivity);
        view.setText("设置");
        view.setTextColor(Color.RED);
        view.setTextSize(22);
        view.setGravity(Gravity.CENTER);

        flContent.addView(view);
    }

}

SettingPager

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