Question

我正在使用导航抽屉在我的应用中显示一些片段。不知何故，我无法使用片段容器在MainActivity中看到它们。也许我忽略了一些事情，有人可以帮忙吗？

提前谢谢。

MainActivity java：

import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v4.app.FragmentTransaction;
import android.view.View;
import android.support.design.widget.NavigationView;
import android.support.v4.view.GravityCompat;
import android.support.v4.widget.DrawerLayout;
import android.support.v7.app.ActionBarDrawerToggle;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.Menu;
import android.view.MenuItem;


public class MainActivity extends AppCompatActivity implements NavigationView.OnNavigationItemSelectedListener {

    NavigationView navigationView = null;
    Toolbar toolbar = null;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        // Set the fragment initially

        MainFragment fragment = new MainFragment();
        FragmentTransaction transaction =
                getSupportFragmentManager().beginTransaction();
        transaction.replace(R.id.fragment_container, fragment);
        transaction.commit();

        toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);

        FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
        fab.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
                        .setAction("Action", null).show();
            }
        });
        DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
        ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(
                this, drawer, toolbar, R.string.navigation_drawer_open, R.string.navigation_drawer_close);
        drawer.setDrawerListener(toggle);
        toggle.syncState();

        navigationView = (NavigationView) findViewById(R.id.nav_view);
        navigationView.setNavigationItemSelectedListener(this);
    }

    @Override
    public void onBackPressed() {
        DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
        if (drawer.isDrawerOpen(GravityCompat.START)) {
            drawer.closeDrawer(GravityCompat.START);
        } else {
            super.onBackPressed();
        }
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.menu_main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();

        //noinspection SimplifiableIfStatement
//        if (id == R.id.action_settings) {
//            return true;
//        }

        return super.onOptionsItemSelected(item);
    }

    @SuppressWarnings("StatementWithEmptyBody")
    @Override
    public boolean onNavigationItemSelected(MenuItem item) {
        // Handle navigation view item clicks here.
        int id = item.getItemId();

        if (id == R.id.nav_camera) {
            // Set the fragment initially
            MainFragment fragment = new MainFragment();
            FragmentTransaction transaction =
                    getSupportFragmentManager().beginTransaction();
            transaction.replace(R.id.fragment_container, fragment);
            transaction.commit();
            // Handle the camera action
        } else if (id == R.id.nav_gallery) {
            // Set the fragment initially
            FactuurFragment fragment = new FactuurFragment();
            FragmentTransaction transaction =
                    getSupportFragmentManager().beginTransaction();
            transaction.replace(R.id.fragment_container, fragment);
            transaction.commit();

        } else if (id == R.id.nav_slideshow) {

        } else if (id == R.id.nav_manage) {

        } else if (id == R.id.nav_share) {

        } else if (id == R.id.nav_send) {

        }

        DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
        drawer.closeDrawer(GravityCompat.START);
        return true;
    }
}

包含片段容器的App_bar_main.xml：

<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true"
tools:context=".MainActivity">

<android.support.design.widget.AppBarLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar">

    <android.support.v7.widget.Toolbar
        android:id="@+id/toolbar"
        android:layout_width="match_parent"
        android:layout_height="?attr/actionBarSize"
        android:background="?attr/colorPrimary"
        app:popupTheme="@style/ThemeOverlay.AppCompat.Dark.ActionBar" />

</android.support.design.widget.AppBarLayout>

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

</FrameLayout>

<android.support.design.widget.FloatingActionButton
    android:id="@+id/fab"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_gravity="bottom|end"
    android:layout_margin="@dimen/fab_margin"
    android:src="@android:drawable/ic_dialog_email" />

</android.support.design.widget.CoordinatorLayout>

Main Fragment.xml：

<FrameLayout
xmlns: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"
tools:context=".MainFragment">

<Button
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="MAIN"
    android:padding="8dp"
    android:textColor="#fff"
    android:background="@color/colorPrimary"
    android:textSize="28sp"
    android:id="@+id/main_button"
    android:layout_centerVertical="true"
    android:layout_centerHorizontal="true" /> 
</FrameLayout>

MainFragment java：

import android.os.Bundle; 
import android.support.v4.app.Fragment;
import android.view.LayoutInflater; 
import android.view.View; 
import android.view.ViewGroup; 
import android.widget.Button;

public class MainFragment extends Fragment {


public MainFragment() {
    // Required empty public constructor
}


@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    View rootView = inflater.inflate(R.layout.fragment_main, container, false);

    final Button mainButton = (Button) rootView.findViewById(R.id.main_button);
    mainButton.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {

                 mainButton.setBackgroundColor(getContext().getResources().getColor(R.color.colorAccent));
        }
    });
    // Inflate the layout for this fragment
    return rootView;
}

}

修改 activity_main.xml中：

<?xml version="1.0" encoding="utf-8"?>
<android.support.v4.widget.DrawerLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/drawer_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true"
tools:openDrawer="start">

<include
    layout="@layout/app_bar_main"
    android:layout_width="match_parent"
    android:layout_height="match_parent" />

<android.support.design.widget.NavigationView
    android:id="@+id/nav_view"
    android:layout_width="wrap_content"
    android:layout_height="match_parent"
    android:layout_gravity="start"
    android:fitsSystemWindows="true"
    app:headerLayout="@layout/nav_header_main"
    app:menu="@menu/activity_main_drawer" />

</android.support.v4.widget.DrawerLayout>

Answer 1

一切都没问题，除了你的片段内容留在工具栏后面，你没有看到它。在顶部添加一个带有操作栏大小的边距，您将看到该按钮。

android:layout_marginTop="?android:attr/actionBarSize"

所以，它会是这样的。

<FrameLayout
            android:id="@+id/fragment_container"
            android:layout_width="match_parent"
            android:layout_marginTop="?android:attr/actionBarSize"
            android:layout_height="match_parent">

另外，我将Action bar视图与主片段容器分开。将主片段容器移动到主活动布局。

没有使用导航抽屉显示的碎片

1 个答案: