我所取得的成就
我正在开发一个 Android 应用程序，该应用程序使用附加到我的 MainActivity 的导航抽屉，以在用户选择导航项时显示某些布局。我还为应该出现在 appBar 中的溢出菜单创建了一个菜单资源文件。
我无法实现的目标
但是，无论用户选择的导航抽屉项目如何，我创建的溢出菜单都会显示在 appBar 中。如果可能，我需要在显示布局日历/设置时从 appBar 隐藏此溢出菜单。（代码如下）
我试图做的事
我尝试使用该setHasOptionsMenu()方法并将其设置为 false 在我的日历/设置 Java 文件中。
申请代码
主要活动
package com.example.lukeb.calendar;
import android.app.Activity;
import android.app.Fragment;
import android.content.Intent;
import android.os.Build;
import android.support.annotation.NonNull;
import android.support.design.widget.NavigationView;
import android.support.v4.app.FragmentActivity;
import android.support.v4.view.GravityCompat;
import android.support.v4.widget.DrawerLayout;
import android.support.v7.app.ActionBar;
import android.support.v7.app.ActionBarDrawerToggle;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.support.v7.widget.Toolbar;
import android.text.Html;
import android.transition.Visibility;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.widget.RelativeLayout;
public class MainActivity extends AppCompatActivity implements NavigationView.OnNavigationItemSelectedListener{
// Declare needed objects as global variables for access throughout the program
RelativeLayout lay1;
RelativeLayout lay2;
RelativeLayout lay3;
DrawerLayout drawerLayout;
ActionBar actionBar;
Toolbar toolbar;
// Default method called automatically when activity is created
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main); // Set the content of this activity to the activity_main XML file
navigate(); // Once finished with this, call the navigate function found below
}
// Method created to prep navigation drawer
public void navigate(){ // Method called in onCreate method
// If device is running Lollipop or above, run the following...
if(Build.VERSION.SDK_INT >= 21) {
toolbar = (Toolbar) findViewById(R.id.toolbar3); // Set variable "toolbar" to item named "toolbar3" in XML file
setSupportActionBar(toolbar); // Designate the item set to "toolbar" as the activity's actionBar
actionBar = getSupportActionBar(); // Set variable "actionBar" to whatever the activity's actionBar is. This is necessary for checking it later.
lay1 = (RelativeLayout) findViewById(R.id.one); // Initialize variables "lay1", "lay2", and "lay3" - that were originally declared above - to their respective XML items.
lay2 = (RelativeLayout) findViewById(R.id.two); // < __________________________| |
lay3 = (RelativeLayout) findViewById(R.id.three); // < ______________________________________|
drawerLayout = (DrawerLayout) findViewById(R.id.dLayout); // Initialize variable "drawerLayout" to XML item "dLayout".
if (actionBar != null) { // Check if the activity's actionBar has been set (not equal to null)
actionBar.setDisplayHomeAsUpEnabled(true); // Enables the actionBar's back button
ActionBarDrawerToggle mDrawerToggle = new ActionBarDrawerToggle(this, drawerLayout, toolbar, R.string.navigation_drawer_open, R.string.navigation_drawer_close) { // Create a new AppDrawer toggle. Refer to android documentation for more info on parameters. Also defines its own constructor after the class object.
public void onDrawerClosed(View view) { // Method called when drawer is closed
supportInvalidateOptionsMenu(); // Declare that the options menu has changed, so should be recreated. It will be recreated when needed.
}
public void onDrawerOpened(View drawerView){ // Method called when drawer is opened
supportInvalidateOptionsMenu(); // Once again, declare that the options menu has changed, so should be recreated. It will be recreated when needed.
}
};
mDrawerToggle.setDrawerIndicatorEnabled(true); // Enable drawer indicator on the "mDrawerToggle" which, in turn, enables the animated glyph on the activity's actionBar
drawerLayout.setDrawerListener(mDrawerToggle); // Set the appDrawer's actionListener to our newly created "mDrawerToggle" object
mDrawerToggle.syncState(); // Sync the appDrawer's indicator with the current state of the DrawerLayout
setListener(); // Call the setListener method below
}
}
}
// Sets the item listener
public void setListener(){
NavigationView nView = (NavigationView) findViewById(R.id.nav_view); // Declare a variable named "nView" and initialize it to the "nav_view" XML item.
nView.setNavigationItemSelectedListener(this); // Set the listener called for a selected navDrawer item to one found below
}
// A method that is called when a navDrawer item is selected
@Override
public boolean onNavigationItemSelected(@NonNull MenuItem item) {
switch(item.getItemId()){ // Check which item was selected by returning its ID
case R.id.action_feed: // If the item selected's ID is "R.id.action_feed"
actionBar.setTitle("Your Feed"); // Set actionBar title to correct page title
lay3.setVisibility(View.GONE); // Hide layout3 from the "stack of layouts"
lay2.setVisibility(View.GONE); // Hide layout2 from the "stack of layouts"
lay1.setVisibility(View.VISIBLE); // Show only the selected item on screen
break; // Leave or "break" from the loop
case R.id.action_calendar: // If the item selected's ID is "R.id.action_calendar"
actionBar.setTitle("Calendar"); // Set actionBar title to correct page title
lay1.setVisibility(View.GONE); // Hide layout1 from the "stack of layouts"
lay3.setVisibility(View.GONE); // Hide layout3 from the "stack of layouts"
lay2.setVisibility(View.VISIBLE); // Show only the selected item on screen
break; // Leave or "break" from the loop
case R.id.action_settings: // If the item selected's ID is "R.id.action_settings"
actionBar.setTitle("Settings"); // Set actionBar title to correct page title
lay1.setVisibility(View.GONE); // Hide layout1 from the "stack of layouts"
lay2.setVisibility(View.GONE); // Hide layout3 from the "stack of layouts"
lay3.setVisibility(View.VISIBLE); // Show only the selected item on screen
break; // Leave or "break" from the loop
}
drawerLayout.closeDrawer(GravityCompat.START); // Regardless of selection, close drawer when loaded
return true; // Return true if navDrawer item was indeed selected
}
public boolean newEvent(MenuItem item){
Intent i = new Intent(MainActivity.this, NewEvent.class);
startActivity(i);
return true;
}
}
FragOne
package com.example.lukeb.calendar;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.View;
import android.view.ViewGroup;
public class FragOne extends Fragment {
@Override
public void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setHasOptionsMenu(true);
}
@Override
@Nullable
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState){
// Creates a new view for the fragment. Then, it sets the XML layout file as the contents of the view. Finally, a copy of this new view is returned.
return inflater.inflate(R.layout.fragment_frag_one, container, false);
}
@Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater){
//inflater = getMenuInflater();
inflater.inflate(R.menu.overflow_one, menu);
super.onCreateOptionsMenu(menu, inflater);
}
}
片段二
package com.example.lukeb.calendar;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.View;
import android.view.ViewGroup;
public class FragTwo extends Fragment {
@Override
public void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setHasOptionsMenu(false);
}
@Override
@Nullable
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState){
// Creates a new view for the fragment. Then, it sets the XML layout file as the contents of the view. Finally, a copy of this new view is returned.
return inflater.inflate(R.layout.fragment_frag_two, container, false);
}
@Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
super.onCreateOptionsMenu(menu, inflater);
menu.clear();
}
}