Question

所以我遇到的问题是我无法在片段之间切换 - 我假设主屏幕也是另一个片段。当我单击操作栏并选择第一个项目“导入”时，它切换到下一个窗口，但问题是它没有替换片段，它看起来只是添加到主片段..我该如何修复这个？所以我可以查看单独的新片段？

在我的主要活动中 -

public boolean onNavigationItemSelected(MenuItem item) {
    // Handle navigation view item clicks here.
    FragmentManager fragmentManager = getSupportFragmentManager();
    FragmentTransaction ft = fragmentManager.beginTransaction();


    int id = item.getItemId();

    if (id == R.id.nav_camera) {
        BlankFragment fragment = new BlankFragment().newInstance();
        ft.replace(R.id.container, fragment).commit();

    } else if (id == R.id.nav_gallery) {
        BlankFragment fragment = new BlankFragment().newInstance();
        ft.replace(R.id.container, fragment).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;
}

content_mail.xml -

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
android:paddingBottom="@dimen/activity_vertical_margin"
app:layout_behavior="@string/appbar_scrolling_view_behavior"
tools:showIn="@layout/app_bar_main"
tools:context="com.prototype.casula.myapp.MainActivity">

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

<TextView
    android:text="Hello World!"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content" />
</RelativeLayout>

BlankFragment.java 在这个类中，我不得不注释掉一些行“抛出新的RuntimeException（context.toString（）”，因为它崩溃了应用程序。我知道这很糟糕。包com.prototype.casula.myapp;

import android.content.Context;
import android.net.Uri;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

public class BlankFragment extends Fragment {
// TODO: Rename parameter arguments, choose names that match
// the fragment initialization parameters, e.g. ARG_ITEM_NUMBER
private static final String ARG_PARAM1 = "param1";
private static final String ARG_PARAM2 = "param2";

// TODO: Rename and change types of parameters
private String mParam1;
private String mParam2;

private OnFragmentInteractionListener mListener;

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

/**
 * Use this factory method to create a new instance of
 * this fragment using the provided parameters.
 *

 * @return A new instance of fragment BlankFragment.
 */
// TODO: Rename and change types and number of parameters
public static BlankFragment newInstance() {
    BlankFragment fragment = new BlankFragment();
    Bundle args = new Bundle();
    //args.putString(ARG_PARAM1, param1);
    //args.putString(ARG_PARAM2, param2);
    fragment.setArguments(args);
    return fragment;
}

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    if (getArguments() != null) {
        mParam1 = getArguments().getString(ARG_PARAM1);
        mParam2 = getArguments().getString(ARG_PARAM2);
    }
}

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    // Inflate the layout for this fragment
    return inflater.inflate(R.layout.fragment_blank, container, false);
}

// TODO: Rename method, update argument and hook method into UI event
public void onButtonPressed(Uri uri) {
    if (mListener != null) {
        mListener.onFragmentInteraction(uri);
    }
}

@Override
public void onAttach(Context context) {
    super.onAttach(context);
    if (context instanceof OnFragmentInteractionListener) {
        mListener = (OnFragmentInteractionListener) context;
    } else {
        //throw new RuntimeException(context.toString()
          //      + " must implement OnFragmentInteractionListener");
    }
}

@Override
public void onDetach() {
    super.onDetach();
    mListener = null;
}

/**
 * This interface must be implemented by activities that contain this
 * fragment to allow an interaction in this fragment to be communicated
 * to the activity and potentially other fragments contained in that
 * activity.
 * <p/>
 * See the Android Training lesson <a href=
 * "http://developer.android.com/training/basics/fragments/communicating.html"
 * >Communicating with Other Fragments</a> for more information.
 */
public interface OnFragmentInteractionListener {
    // TODO: Update argument type and name
    void onFragmentInteraction(Uri uri);
}
}

BlankFragment 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="com.prototype.casula.myapp.BlankFragment">

<!-- TODO: Update blank fragment layout -->
<TextView
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:text="@string/hello_blank_fragment" />

<ImageView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/imageView2"
    android:layout_gravity="center"
    android:src="@mipmap/ic_launcher" />

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="You finally figured it out?"
    android:layout_gravity="center_horizontal|top" />

</FrameLayout>

使用导航抽屉切换片段（Android Studio 1.5.1）

0 个答案: