setNavigationItemSelectedListener不起作用
我的NavigationViewonClick活动无法正常进行。
以下是我一一尝试过的代码段，但无济于事：
NavigationView.OnNavigationItemSelectedListener使用OnClick()方法实施- 设定
NavigationItemSelectedListener方法
nav = (NavigationView)findViewById(R.id.nav); nav.setNavigationItemSelectedListener(new NavigationView.OnNavigationItemSelectedListener() {
@Override
public boolean onNavigationItemSelected(MenuItem item) {
Toast.makeText(getApplicationContext(),"Hello",Toast.LENGTH_SHORT).show();
return true;
}
});
- 使用
OnOptionItemSelected()方法
@Override public boolean onOptionsItemSelected(MenuItem item) {
if(toggle.onOptionsItemSelected(item))
{
return true;
}
switch (item.getItemId()) {
case R.id.lib:
Toast.makeText(getApplicationContext(),"OK",Toast.LENGTH_SHORT).show();
return true;
case R.id.fav:
Toast.makeText(getApplicationContext(),"OK",Toast.LENGTH_SHORT).show();
return true;
}
return super.onOptionsItemSelected(item);
}
这是我完整的MainActivity.java文件：
public class MainActivity extends AppCompatActivity{ public frag_song song;
public frag_artist artist;
public frag_album album;
public TabLayout tab;
Uri songUri;
Cursor songCursor;
public static LinearLayout mainLayout;
int songTitle,songArtist,duration,data,songAlbum;
public NavigationView nav;
public DrawerLayout layout;
public ActionBarDrawerToggle toggle;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ActionBar actionBar = getSupportActionBar();
actionBar.setDisplayOptions(ActionBar.DISPLAY_SHOW_HOME);
//actionBar.setIcon(R.drawable.logo);
mainLayout = (LinearLayout)findViewById(R.id.main);
//All Stuff Of NAvigatin Drawer
layout = (DrawerLayout)findViewById(R.id.drawerL);
toggle = new ActionBarDrawerToggle(MainActivity.this,layout,R.string.open,R.string.close);
layout.addDrawerListener(toggle);
toggle.syncState();
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
nav = (NavigationView)findViewById(R.id.nav);
nav.setNavigationItemSelectedListener(new NavigationView.OnNavigationItemSelectedListener() {
@Override
public boolean onNavigationItemSelected(MenuItem item) {
Toast.makeText(getApplicationContext(),"Hello",Toast.LENGTH_SHORT).show();
return true;
}
});//Not Working
nav.setItemIconTintList(null);
//check if app open first time or not
SharedPreferences prefs = this.getSharedPreferences("com.blackhat.rhythmbox", Context.MODE_PRIVATE);
Boolean first = prefs.getBoolean("first", true);
if(first){
//Adding song To Database
addtoDatabase();
prefs.edit().putBoolean("first",false).commit();
}
//Decaring Object of Fragment
//TO access Tab
tab = (TabLayout)findViewById(R.id.tabs);
song = new frag_song();
artist = new frag_artist();
album = new frag_album();
//addding tab to tab layout
tab.addTab(tab.newTab().setText("Songs"),true);
tab.addTab(tab.newTab().setText("ALbum"));
tab.addTab(tab.newTab().setText("Artist"));
tab.getTabAt(0).setIcon(R.drawable.icons_song);
tab.getTabAt(1).setIcon(R.drawable.icons_album);
tab.getTabAt(2).setIcon(R.drawable.icon_artist);
//setting default tab
FragmentManager fm = getSupportFragmentManager();
fm.beginTransaction().replace(R.id.frame_container,song).commit();
//on tab select
tab.setOnTabSelectedListener(new TabLayout.OnTabSelectedListener() {
@Override
public void onTabSelected(TabLayout.Tab tab) {
switch (tab.getPosition())
{
case 0 :
FragmentManager f_song = getSupportFragmentManager();
f_song.beginTransaction().replace(R.id.frame_container,song).commit();
break;
case 1 :
FragmentManager f_artist = getSupportFragmentManager();
f_artist.beginTransaction().replace(R.id.frame_container,album).commit();
break;
case 2 :
FragmentManager f_album = getSupportFragmentManager();
f_album.beginTransaction().replace(R.id.frame_container,artist).commit();
break;
}
}
@Override
public void onTabUnselected(TabLayout.Tab tab) {
}
@Override
public void onTabReselected(TabLayout.Tab tab) {
}
});
}
@Override
protected void onStop() {
super.onStop();
}
public void addtoDatabase(){
song_db dbHelper = new song_db(getApplicationContext());
SQLiteDatabase db = dbHelper.getWritableDatabase();
ContentValues contentValues = new ContentValues();
ContentResolver contentResolver = getContentResolver();
songUri = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
songCursor = contentResolver.query(songUri, null, null, null, null);
//checking if cursor is null or not
if(songCursor !=null && songCursor.moveToFirst()){
songTitle = songCursor.getColumnIndex(MediaStore.Audio.Media.TITLE);
songArtist = songCursor.getColumnIndex(MediaStore.Audio.Media.ARTIST);
duration = songCursor.getColumnIndex(MediaStore.Audio.Media.DURATION);
songAlbum = songCursor.getColumnIndex(MediaStore.Audio.Media.ALBUM);
data = songCursor.getColumnIndex(MediaStore.Audio.Media.DATA);
Toast.makeText(getApplicationContext(),"Loaded",Toast.LENGTH_SHORT).show();
do{
contentValues.put("name",songCursor.getString(songTitle));
contentValues.put("artist",songCursor.getString(songArtist));
contentValues.put("album",songCursor.getString(songAlbum));
contentValues.put("path",songCursor.getString(data));
contentValues.put("duration",songCursor.getString(duration));
contentValues.put("isfavorite",0);
contentValues.put("playlist","regular");
// contentValues.put("name",songCursor.getString(songArtist));
db.insert("songs",null,contentValues);
}while (songCursor.moveToNext());
}
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
if(toggle.onOptionsItemSelected(item))
{
return true;
}
return super.onOptionsItemSelected(item);
}
}
回答：
我遇到了同样的问题，我发现Android非常注重布局XML。我将NavigationView作为DrawerLayout的第一个孩子，但是出于某些愚蠢的原因，它必须是最后一个孩子。因此，您的布局必须具有以下顺序的元素：
<DrawerLayout> <FrameLayout/>
<NavigationView/>
</DrawerLayout>
不按此顺序：
<DrawerLayout> <NavigationView/>
<FrameLayout/>
</DrawerLayout>
以上是 setNavigationItemSelectedListener不起作用 的全部内容， 来源链接： utcz.com/qa/430905.html
