我在我的应用程序中使用了NavigationDrawer模板但是Intent的功能无法正常工作。我已经在类声明中实现了导航监听器，但仍然没有使用意图导航。这是我第一次陷入困境的地方。我搜索了很多网站，但我的申请中没有发生任何事情。你能帮助我吗？我添加了一些额外的评论，请不要考虑它
public class MainActivity extends AppCompatActivity
implements ViewPager.OnPageChangeListener {
/**
* Extra to add the the launch intent to specify that user comes from the notification (used to
* show not the current month but the last one)
*/
public static final String FROM_NOTIFICATION_EXTRA = "fromNotif";
/**
* List of first date of each month available
*/
private List<Date> dates;
/**
* TextView that displays the name of the month
*/
private TextView monthTitleTv;
/**
* Button to go the previous month
*/
private Button previousMonthButton;
/**
* Button to go the next month
*/
private Button nextMonthButton;
/**
* ViewPager used to display each month in a Fragment
*/
private ViewPager pager;
/**
* The current {@link #pager} position
*/
private int selectedPosition;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
final ProgressBar progressBar = (ProgressBar) findViewById(R.id.monthly_report_progress_bar);
final View content = findViewById(R.id.monthly_report_content);
monthTitleTv = (TextView) findViewById(R.id.monthly_report_month_title_tv);
previousMonthButton = (Button) findViewById(R.id.monthly_report_previous_month_button);
nextMonthButton = (Button) findViewById(R.id.monthly_report_next_month_button);
pager = (ViewPager) findViewById(R.id.monthly_report_view_pager);
previousMonthButton.setText("<");
nextMonthButton.setText(">");
previousMonthButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (selectedPosition > 0) {
selectPagerItem(selectedPosition - 1, true);
}
}
});
nextMonthButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (selectedPosition < dates.size() - 1) {
selectPagerItem(selectedPosition + 1, true);
}
}
});
UIHelper.removeButtonBorder(previousMonthButton);
UIHelper.removeButtonBorder(nextMonthButton);
// Load list of monthly asynchronously since it can take time
new AsyncTask<Void, Void, List<Date>>() {
@Override
protected List<Date> doInBackground(Void... params) {
return DateHelper.getListOfMonthsAvailableForUser(MainActivity.this);
}
@Override
protected void onPostExecute(List<Date> dates) {
if (isFinishing()) {
return;
}
MainActivity.this.dates = dates;
configureViewPager();
progressBar.setVisibility(View.GONE);
content.setVisibility(View.VISIBLE);
}
}.execute();
}
private void configureViewPager() {
pager.setOffscreenPageLimit(0);
pager.setAdapter(new FragmentPagerAdapter(getSupportFragmentManager()) {
@Override
public Fragment getItem(int position) {
return new MonthlyReportFragment(dates.get(position));
}
@Override
public int getCount() {
return dates.size();
}
});
pager.addOnPageChangeListener((ViewPager.OnPageChangeListener) this);
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(new NavigationView.OnNavigationItemSelectedListener() {
@Override
public boolean onNavigationItemSelected(@NonNull MenuItem item) {
int id = item.getItemId();
switch (id) {
case R.id.nav_camera:
Intent i = new Intent(MainActivity.this, Monthly_ExpenseEdit_activity.class);
startActivity(i);
break;
case R.id.nav_gallery:
Intent i1 = new Intent(MainActivity.this, ExpenseEditActivity.class);
startActivity(i1);
break;
}
return false;
}
});
}
/**
* Extra to add the the launch intent to specify that user comes from the notification (used to
* show not the current month but the last one)
*/
@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;
}
private void selectPagerItem(int position, boolean animate)
{
pager.setCurrentItem(position, animate);
onPageSelected(position);
}
@Override
public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
}
/**
* Extra to add the the launch intent to specify that user comes from the notification (used to
* show not the current month but the last one)
*/
@Override
public void onPageSelected(int position)
{
selectedPosition = position;
Date date = dates.get(position);
monthTitleTv.setText(DateHelper.getMonthTitle(this, date));
// Last and first available month
boolean last = position == dates.size() - 1;
boolean first = position == 0;
/ ** *额外添加启动意图以指定用户来自通知（用于 *显示不是当前月份而是最后一个月） * /
nextMonthButton.setEnabled(!last);
nextMonthButton.setTextColor(ContextCompat.getColor(this, last ? R.color.monthly_report_disabled_month_button : android.R.color.white));
previousMonthButton.setEnabled(!first);
previousMonthButton.setTextColor(ContextCompat.getColor(this, first ? R.color.monthly_report_disabled_month_button : android.R.color.white));
}
@Override
public void onPageScrollStateChanged(int state) {
}
}
XML:
<android.support.v4.widget.DrawerLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/drawer_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true"
tools:openDrawer="start">
<include
layout="@layout/app_bar_main"
android:layout_width="match_parent"
android:layout_height="match_parent" />
<android.support.design.widget.NavigationView
android:id="@+id/nav_view"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_gravity="start"
android:fitsSystemWindows="true"
app:headerLayout="@layout/nav_header_main"
app:menu="@menu/activity_main_drawer" />
<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=".view.MonthlyReportActivity">
<ProgressBar android:id="@+id/monthly_report_progress_bar"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:indeterminate="true" />
<LinearLayout android:id="@+id/monthly_report_content"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="47dp"
android:orientation="horizontal"
android:paddingLeft="10dp"
android:paddingRight="10dp"
android:gravity="center_vertical"
android:background="@color/primary_dark">
<Button
android:id="@+id/test"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
/>
<Button android:id="@+id/monthly_report_previous_month_button"
android:layout_width="50dp"
android:layout_height="wrap_content"
android:textColor="@android:color/white"
android:textSize="24dp"
android:background="@drawable/calendar_month_switcher_button_drawable" />
<TextView android:id="@+id/monthly_report_month_title_tv"
android:layout_width="0dip"
android:layout_height="wrap_content"
android:layout_weight="1.0"
android:textSize="21dp"
android:textColor="@android:color/white"
android:textAllCaps="true"
android:gravity="center" />
<Button android:id="@+id/monthly_report_next_month_button"
android:layout_width="50dp"
android:layout_height="wrap_content"
android:textColor="@android:color/white"
android:textSize="24dp"
android:background="@drawable/calendar_month_switcher_button_drawable" />
</LinearLayout>
<android.support.v4.view.ViewPager
android:id="@+id/monthly_report_view_pager"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
</LinearLayout>
</FrameLayout>
</android.support.v4.widget.DrawerLayout>
答案 0 :(得分：0)
在onNavigationItemSelected()方法中返回true而不是false
还要确保导航抽屉菜单中存在ID。
app:menu="@menu/menu_navigation"
使用此代码：
@Override
public boolean onNavigationItemSelected(@NonNull MenuItem item) {
int id = item.getItemId();
switch (id) {
case R.id.nav_camera:
Intent i = new Intent(MainActivity.this, Monthly_ExpenseEdit_activity.class);
startActivity(i);
break;
case R.id.nav_gallery:
Intent i1 = new Intent(MainActivity.this, ExpenseEditActivity.class);
startActivity(i1);
break;
}
return true; //change here
}