我试图将我的片段中的内容放入android studio的主视图中。
该应用程序编译并运行。但是当我在导航抽屉（滑动菜单）中选择一个带有片段的列表中的项目时：它是空白的。
我的片段包含嵌入式YouTube播放器。
logCat没有显示错误......
从我的代码 - 我在看什么是错的？
这里是主要活动：
import android.app.Activity;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.widget.DrawerLayout;
import android.support.v7.app.ActionBar;
import android.support.v7.app.AppCompatActivity;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ListView;
public class MainActivity extends AppCompatActivity
implements NavigationDrawerFragment.NavigationDrawerCallbacks {
/**
* Fragment managing the behaviors, interactions and presentation of the navigation drawer.
*/
private NavigationDrawerFragment mNavigationDrawerFragment;
/**
* Used to store the last screen title. For use in {@link #restoreActionBar()}.
*/
private CharSequence mTitle;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mNavigationDrawerFragment = (NavigationDrawerFragment)
getSupportFragmentManager().findFragmentById(R.id.navigation_drawer);
mTitle = getTitle();
// Set up the drawer.
mNavigationDrawerFragment.setUp(
R.id.navigation_drawer,
(DrawerLayout) findViewById(R.id.drawer_layout));
}
@Override
public void onNavigationDrawerItemSelected(int position) {
// update the main content by replacing fragments
FragmentManager fragmentManager = getSupportFragmentManager();
fragmentManager.beginTransaction()
.replace(R.id.container, PlaceholderFragment.newInstance(position + 1))
.commit();
}
public void onSectionAttached(int number) {
switch (number) {
case 1:
mTitle = getString(R.string.title_section1);
break;
case 2:
mTitle = getString(R.string.title_section2);
break;
case 3:
mTitle = getString(R.string.title_section3);
break;
case 4:
mTitle = getString(R.string.title_section4);
break;
case 5:
mTitle = getString(R.string.title_section5);
break;
}
}
public void restoreActionBar() {
ActionBar actionBar = getSupportActionBar();
actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_STANDARD);
actionBar.setDisplayShowTitleEnabled(true);
actionBar.setTitle(mTitle);
}
private class SlideMenuClickListener implements
ListView.OnItemClickListener {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position,
long id) {
// display view for selected nav drawer item
//displayView(position);
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
if (!mNavigationDrawerFragment.isDrawerOpen()) {
// Only show items in the action bar relevant to this screen
// if the drawer is not showing. Otherwise, let the drawer
// decide what to show in the action bar.
getMenuInflater().inflate(R.menu.main, menu);
restoreActionBar();
return true;
}
return super.onCreateOptionsMenu(menu);
}
@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);
}
/**
* A placeholder fragment containing a simple view.
*/
public static class PlaceholderFragment extends Fragment {
/**
* The fragment argument representing the section number for this
* fragment.
*/
private static final String ARG_SECTION_NUMBER = "section_number";
/**
* Returns a new instance of this fragment for the given section
* number.
*/
public static PlaceholderFragment newInstance(int sectionNumber) {
PlaceholderFragment fragment = new PlaceholderFragment();
Bundle args = new Bundle();
args.putInt(ARG_SECTION_NUMBER, sectionNumber);
fragment.setArguments(args);
return fragment;
}
public PlaceholderFragment() {
}
/* @Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_main, container, false);
return rootView;
} */
@Override
public void onAttach(Activity activity) {
super.onAttach(activity);
((MainActivity) activity).onSectionAttached(
getArguments().getInt(ARG_SECTION_NUMBER));
}
}
}
这是片段类：
import android.app.Fragment;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import com.google.android.youtube.player.YouTubeInitializationResult;
import com.google.android.youtube.player.YouTubePlayer;
import com.google.android.youtube.player.YouTubePlayerView;
public class MasjidAlHaramFragment extends Fragment implements YouTubePlayer.OnInitializedListener {
public String API_KEY = "xxxxxxxxxxxxxxxxxxxxx";
//http://youtu.be/<VIDEO_ID>
//final String VIDEO_ID = "4OoKpZWJASY";
public String VIDEO_ID_2 = "VopbGPJVkzM";
public MasjidAlHaramFragment () {
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_masjidharam, container, false);
//http://youtu.be/<VIDEO_ID>
//final String VIDEO_ID = "4OoKpZWJASY";
//final String VIDEO_ID_2 = "VopbGPJVkzM";
/** Initializing YouTube player view **/
YouTubePlayerView youTubePlayerView = null;
if (youTubePlayerView != null)
youTubePlayerView = (YouTubePlayerView) getView().findViewById(R.id.youtube_player);
youTubePlayerView.initialize(API_KEY, this);
return rootView;
}
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
/** attaching layout xml **/
//setContentView(R.layout.activity_main);
}
public void onInitializationFailure(YouTubePlayer.Provider provider, YouTubeInitializationResult result) {
//Toast.makeText(this,"Failured to Initialize!", Toast.LENGTH_LONG).show();
}
public void onInitializationSuccess(YouTubePlayer.Provider provider, YouTubePlayer player, boolean wasRestored) {
/** add listeners to YouTubePlayer instance **/
player.setPlayerStateChangeListener(playerStateChangeListener);
player.setPlaybackEventListener(playbackEventListener);
/** Start buffering **/
if (!wasRestored) {
player.cueVideo(VIDEO_ID_2);
}
}
YouTubePlayer.PlaybackEventListener playbackEventListener = new YouTubePlayer.PlaybackEventListener() {
@Override
public void onBuffering(boolean arg0) {
}
@Override
public void onPaused() {
}
@Override
public void onPlaying() {
}
@Override
public void onSeekTo(int arg0) {
}
@Override
public void onStopped() {
}
};
YouTubePlayer.PlayerStateChangeListener playerStateChangeListener = new YouTubePlayer.PlayerStateChangeListener() {
@Override
public void onAdStarted() {
}
@Override
public void onError(YouTubePlayer.ErrorReason arg0) {
}
@Override
public void onLoaded(String arg0) {
}
@Override
public void onLoading() {
}
@Override
public void onVideoEnded() {
}
@Override
public void onVideoStarted() {
}
};
}
这是XML视图
<?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="match_parent">
<com.google.android.youtube.player.YouTubePlayerView
android:id="@+id/youtube_player"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#fff"
android:padding="5dp" />
</RelativeLayout>
感谢。
ironmantis7x
答案 0 :(得分：1)
您需要在片段的onCreateView方法中调用super.onCreateView（...）才能正确绘制片段。
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
super.onCreateView(inflater, container, savedInstanceState);
此外，我建议您执行以下操作，因为存在一些逻辑错误：
View rootView = inflater.inflate(R.layout.fragment_masjidharam, container, false);
YouTubePlayerView youTubePlayerView = null;
// THIS IS ALWAYS FALSE. Comment it out or else it'll never get set.
// if (youTubePlayerView != null)
youTubePlayerView = (YouTubePlayerView) rootView.findViewById(R.id.youtube_player);
// Check for not-null here.
if(youTubePlayerView != null) {
youTubePlayerView.initialize(API_KEY, this);
}