我目前正在创建一个不使用片段的导航菜单。我似乎创建了一个工作系统,它打开类,并通过使用BaseActivity
并将它继承到需要抽屉的类中,从而使导航栏保持在每个阶段。然而,在加载应用程序时,看起来3杆'汉堡'图标不存在,顶部的工具栏也不存在(见图)。导航栏似乎有用,因为我可以从左侧滑动并点击加载其他课程。我觉得我的onCreate()
在我的BaseActivity
是缺少的东西,但用谷歌搜索我似乎无法找到解决方案。抽屉布局汉堡包和工具栏不可见,尽管工作导航抽屉?
图片当前问题:导航栏的
图像的问题,在后台工作:
这是我的基本活动:
import android.content.Intent;
import android.os.Bundle;
import android.support.design.widget.NavigationView;
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.MenuItem;
public class BaseActivity extends AppCompatActivity {
DrawerLayout drawerLayout;
ActionBarDrawerToggle actionBarDrawerToggle;
Toolbar toolbar;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
NavigationView navigationView = (NavigationView) findViewById(R.id.navigation_view);
drawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);
actionBarDrawerToggle = new ActionBarDrawerToggle(this, drawerLayout, toolbar, R.string.drawer_open, R.string.drawer_closed);
drawerLayout.addDrawerListener(actionBarDrawerToggle);
navigationView.setNavigationItemSelectedListener(new NavigationView.OnNavigationItemSelectedListener() {
@Override
public boolean onNavigationItemSelected(MenuItem item) {
Intent anIntent;
switch (item.getItemId()) {
case R.id.nav_homepage:
anIntent = new Intent(getApplicationContext(), homepage.class);
startActivity(anIntent);
drawerLayout.closeDrawers();
break;
case R.id.nav_add_roster:
anIntent = new Intent(getApplicationContext(), add_roster.class);
startActivity(anIntent);
drawerLayout.closeDrawers();
break;
case R.id.nav_check_schedule:
anIntent = new Intent(getApplicationContext(), schedule.class);
startActivity(anIntent);
drawerLayout.closeDrawers();
break;
}
return false;
}
});
}
}
这是我的homepag Ë这就是最初加载:
import android.os.Bundle;
import android.widget.FrameLayout;
public class homepage extends BaseActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
FrameLayout contentFrameLayout = (FrameLayout) findViewById(R.id.content_frame); //Remember this is the FrameLayout area within your content_main.xml
getLayoutInflater().inflate(R.layout.homepage, contentFrameLayout);
}
}
这里是我的活动主:
<?xml version="1.0" encoding="utf-8"?>
<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">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<FrameLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/content_frame"/>
</LinearLayout>
<android.support.design.widget.NavigationView
android:id="@+id/navigation_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" />
</android.support.v4.widget.DrawerLayout>
试过这个在我的谷歌搜索,没有运气恐怕 –
看看我的编辑是否帮助你。 – Cochi
Nada,强制关闭空指针。我正在使用NoActionBar主题,所以这可能是原因... java.lang.NullPointerException:尝试调用虚拟方法'void android.support.v7.app.ActionBar.setHomeButtonEnabled(boolean)'on a null对象引用 –