从导航抽屉中打开新片段时，将content_main替​​换为

Question

我已经用谷歌搜索了，还没有找到答案，我正在使用Android导航抽屉模板，当从导航菜单中单击时，我有一些片段会相互替换，当应用程序第一次打开时，它会在Content_Main布局上打开，当我单击它打开的片段之一，但仍显示content_main的内容，我需要在使用其他片段时隐藏该内容，还需要创建主页按钮，以便我可以从菜单返回该内容，有什么帮助吗？

问题是，当我打开应用程序时，出现Content_main布局，当我将导航抽屉滑过并在菜单中选择nav_gallery时，音乐片段会打开，但内容主菜单不会被替换。

这是我的MainActivity

package com.justmikey.justmik;

 import android.media.MediaPlayer;
 import android.os.Bundle;
 import android.support.design.widget.FloatingActionButton;
 import android.support.design.widget.Snackbar;
 import android.support.v4.app.FragmentManager;
 import android.support.v7.internal.widget.ButtonBarLayout;
 import android.text.method.ScrollingMovementMethod;
 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;
 import android.widget.Button;
 import android.widget.TextView;

 import JustMikey.Fragments.MainFragment;
 import JustMikey.Fragments.MusicFragment;

 public class MainActivity extends AppCompatActivity
    implements NavigationView.OnNavigationItemSelectedListener {

//create a media player object called mp
MediaPlayer mp;
//declare my buttons play, pause and stop
Button play, pause,stop;

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

    //Set the textView scrollMain to scrollable
    TextView tv = (TextView) findViewById(R.id.scrollMain);
    tv.setMovementMethod(new ScrollingMovementMethod());

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

    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 = (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.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) {
    android.app.FragmentManager fm = getFragmentManager();

    int id = item.getItemId();

    if (id == R.id.nav_camara) {

   fm.beginTransaction().replace(R.id.content_frame, new MainFragment()).commit();


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

        fm.beginTransaction().replace(R.id.content_frame, new MusicFragment()).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;
}
 }

这就是content_main

<FrameLayout
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:id="@+id/content_frame">

    <ImageView
        android:layout_width="355dp"
        android:layout_height="wrap_content"
        android:src="@drawable/jmmain"
        android:id="@+id/imageView2"
        android:layout_gravity="center_horizontal|top"
        android:layout_alignRight="@+id/content_frame"
        android:layout_alignEnd="@+id/content_frame" />

    <TextView
        android:layout_width="fill_parent"
        android:layout_height="274dp"
        android:text="hello hello hello hello hello hello hello hello hello  hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello hello "
        android:id="@+id/scrollMain"
        android:layout_gravity="center_horizontal|bottom"
        android:layout_alignBottom="@+id/scrollView"
        android:layout_alignParentLeft="true"
        android:layout_alignParentStart="true"
        android:layout_marginBottom="28dp"
        android:layout_alignParentRight="true"
        android:layout_alignParentEnd="true"
        android:background="#ffffff"
        android:padding="10dp" />

    <ScrollView
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:id="@+id/scrollView"
        android:layout_alignParentLeft="true"
        android:layout_alignParentStart="true"
        android:layout_gravity="center"></ScrollView>


</FrameLayout>

</RelativeLayout>

这是我的音乐

package JustMikey.Fragments;

import android.app.Fragment;
import android.graphics.LightingColorFilter;
import android.graphics.PorterDuff;
import android.media.MediaPlayer;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;

import com.justmikey.justmik.R;

 /**
  *     Created by James on 24/02/2016.
  */
public class MusicFragment extends Fragment implements View.OnClickListener {

//create a media player object called mp
MediaPlayer mp;
//declare my buttons play, pause and stop
Button play, pause,stop;




@Nullable
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle  savedInstanceState) {

    View rootView = inflater.inflate(R.layout.fragmentmusic, container,  false);


    //call my button views in by using the ID tag
    play = (Button) rootView.findViewById(R.id.play);
    pause = (Button) rootView.findViewById(R.id.pause);
    stop = (Button) rootView.findViewById(R.id.stop);

    //set an onClickListener to make my buttons clickable
    play.setOnClickListener(this);
    pause.setOnClickListener(this);
    stop.setOnClickListener(this);

    //Change the colour of the pause button for a nice design effect
    pause.getBackground().setColorFilter(new LightingColorFilter(0x00000000,  0xFFAA0000));
    //return the view
    return rootView;
}
// onClick Method for the play, pause and stop buttons
public void onClick(View v) {
    switch(v.getId()) {
        case R.id.play : if(mp == null) {
            mp = MediaPlayer.create(getActivity(), R.raw.holdmytong);
        }
            mp.start();
            break;
        case R.id.pause : mp.pause();break;

        case R.id.stop : mp.stop();mp = null;break;
    }

    }



}

fragment_music布局

<?xml version="1.0" encoding="utf-8"?>

<ImageView
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:adjustViewBounds="true"
    android:scaleType="fitCenter"
    android:id="@+id/imageView3"
    android:src="@drawable/jmholdmy"
    android:layout_gravity="center_horizontal|top" />

<Button
    style="?android:attr/buttonStyleSmall"
    android:layout_width="100dp"
    android:layout_height="74dp"
    android:id="@+id/pause"
    android:layout_alignTop="@+id/play"
    android:layout_toRightOf="@+id/play"
    android:layout_toEndOf="@+id/play"
    android:layout_gravity="center_horizontal|bottom"
    android:background="@drawable/pausebtnimg" />

<Button
    style="?android:attr/buttonStyleSmall"
    android:layout_width="113dp"
    android:layout_height="72dp"
    android:id="@+id/stop"
    android:layout_alignTop="@+id/play"
    android:layout_toRightOf="@+id/pause"
    android:layout_toEndOf="@+id/pause"
    android:layout_gravity="right|bottom"
    android:background="@drawable/stopbtnimg" />

<Button
    style="?android:attr/buttonStyleSmall"
    android:layout_width="114dp"
    android:layout_height="72dp"
    android:id="@+id/play"
    android:layout_marginTop="170dp"
    android:layout_alignParentLeft="true"
    android:layout_alignParentStart="true"
    android:layout_gravity="left|bottom"
    android:background="@drawable/playbtnimg" />

<TextView
    android:layout_width="match_parent"
    android:layout_height="258dp"
    android:id="@+id/textView4"
    android:layout_gravity="left|bottom"
    android:text="Taking from our debut EP Hold my tongue was our first released song, it won play at the Picnic competition which brought Just Mikey to the stage at the largest festivil in Europe Electric Picnic, This is the first of many to come so enjoy.  " />

<TextView
    android:layout_width="314dp"
    android:layout_height="156dp"
    android:text="Buy Track: https://www.facebook.com/search/top/?q=just%20mikey%20google%20play"
    android:id="@+id/textView5"
    android:layout_gravity="center_horizontal|bottom"
    android:backgroundTint="#000000"
    android:backgroundTintMode="screen" />

Answer 1

AppCompatActivity应该使用通过getSupportFragmentManager()检索的FragmentManager 。

Answer 2

现在回答还为时已晚，但是我在回答，以防万一其他人偶然发现了这个问题。

要显示不带content_main的fragment_music布局，您需要将fragment_music布局的“ Relative Layout ”的背景设置为white （或您想要的任何white ），这样content_main将隐藏，而fragment_layout就是您想要看到的全部。 。