Android Studio Fragment(day12)

最新推荐文章于 2025-07-01 09:28:13 发布

原创最新推荐文章于 2025-07-01 09:28:13 发布 · 363 阅读

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本文围绕Android的Fragment展开，介绍其特点，即用于页面模块化管理，一个Activity中可有多个且不能单独使用。还阐述了显示方式，包括静态和动态显示。说明了创建Fragment的方法，以及Fragment间传值的方式如EventBus，并给出了相关代码片段。

Fragment

特点

碎片用来将页面模块化管理，一个Activity中可以有多个碎片，碎片不可以单独使用

显示方式

1 静态显示
2 动态显示

如何创建Fragment

1 自定义类继承Fragment
2 重写onCreateView(为占位填充布局)

Fragment - Fragment 传值

1.EvectBus
步骤
Fragment 1 发送EventBus.getDefault().postSticky();
Fragment 2 注册，解绑，接受
@SubScrib(threadMode = ThreadMode.Main,sticky = true)
接受方法

代码片段

布局文件
定义数个占位布局之后往里面添加布局文件

<FrameLayout
        android:layout_above="@id/bottom"
        android:layout_width="match_parent"
        android:layout_height="match_parent">
        <FrameLayout
            android:id="@+id/fragment_a"
            android:layout_width="match_parent"
            android:layout_height="match_parent"></FrameLayout>
        <FrameLayout
            android:id="@+id/fragment_b"
            android:layout_width="match_parent"
            android:layout_height="match_parent"></FrameLayout>
        <FrameLayout
            android:id="@+id/fragment_c"
            android:layout_width="match_parent"
            android:layout_height="match_parent"></FrameLayout>
        <FrameLayout
            android:id="@+id/fragment_d"
            android:layout_width="match_parent"
            android:layout_height="match_parent"></FrameLayout>
    </FrameLayout>

自定义类继承Fragment

public class FragmentC extends Fragment {
    @Nullable
    @Override
    public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.layout_c, container, false);
        return view;
    }
}

主类Oncreate

		fragmentA = new FragmentA();
        fragmentB = new FragmentB();
        fragmentC = new FragmentC();
        fragmentD = new FragmentD();

        FragmentManager manager = getSupportFragmentManager();
        FragmentTransaction transaction = manager.beginTransaction();
        transaction.add(R.id.fragment_a,fragmentA);
        transaction.add(R.id.fragment_b,fragmentB);
        transaction.add(R.id.fragment_c,fragmentC);
        transaction.add(R.id.fragment_d,fragmentD);
        transaction.commit();
        
		btn1.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                FragmentManager manager = getSupportFragmentManager();
                FragmentTransaction transaction = manager.beginTransaction();
                transaction.show(fragmentA);
                transaction.hide(fragmentB);
                transaction.hide(fragmentC);
                transaction.hide(fragmentD);
                transaction.commit();
            }
        });

        btn2.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                FragmentManager manager = getSupportFragmentManager();
                FragmentTransaction transaction = manager.beginTransaction();
                transaction.show(fragmentB);
                transaction.hide(fragmentA);
                transaction.hide(fragmentC);
                transaction.hide(fragmentD);
                transaction.commit();
            }
        });

        btn3.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                FragmentManager manager = getSupportFragmentManager();
                FragmentTransaction transaction = manager.beginTransaction();
                transaction.show(fragmentC);
                transaction.hide(fragmentA);
                transaction.hide(fragmentB);
                transaction.hide(fragmentD);
                transaction.commit();
            }
        });

        btn4.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                FragmentManager manager = getSupportFragmentManager();
                FragmentTransaction transaction = manager.beginTransaction();
                transaction.show(fragmentD);
                transaction.hide(fragmentA);
                transaction.hide(fragmentB);
                transaction.hide(fragmentC);
                transaction.commit();
            }
        });