问题
I'm making an Android App for my college using navigation drawer. It has two types of users - students & faculty. So depending upon the email-id/username I want to load the components of respective user in the drawer/slider. I went through this question, which suggests we can use any layout in the child layout: Is it possible to use something other than a listview as sliding drawer in drawerlayout
So in order to implement my logic I wish to use 3 dynamic fragments : login_fragment, student_fragment, faculty_fragment. And then using the username type I will replace the login_fragment with student/faculty_fragment in the drawer. But I'm getting errors in loading the drawer with dynamic fragment.
This is the main_activity code I'm using to load dynamic fragments in the drawer(by drawer I'm mean the slider). The main layout part i.e content_frame is already done using the same approach with no errors.
navigation drawer layout file :
//main_activity.xml layout file
<android.support.v4.widget.DrawerLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/drawer_layout"
android:layout_width="match_parent"
android:layout_height="match_parent">
<!-- As the main content view, the view below consumes the entire
space available using match_parent in both dimensions. -->
<FrameLayout
android:id="@+id/content_frame"
android:layout_width="match_parent"
android:layout_height="match_parent" />
<!-- android:layout_gravity="start" tells DrawerLayout to treat
this as a sliding drawer on the left side for left-to-right
languages and on the right side for right-to-left languages.
The drawer is given a fixed width in dp and extends the full height of
the container. A solid background is used for contrast
with the content view. -->
<FrameLayout
android:id="@+id/left_drawer"
android:layout_width="320dp"
android:layout_height="match_parent"
android:layout_gravity="start"
android:background="#111" >
</FrameLayout>
This is the .java file for the corresponding layout and I think the error is in loading the drawer list layout :
// Main_Activity
package com.kodevelop.gndec;
import android.app.Fragment;
import android.app.FragmentTransaction;
import android.app.SearchManager;
import android.content.Intent;
import android.content.res.Configuration;
import android.os.Bundle;
import android.support.v4.app.ActionBarDrawerToggle;
import android.support.v4.app.FragmentActivity;
import android.support.v4.view.GravityCompat;
import android.support.v4.widget.DrawerLayout;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.Toast;
public class LaunchActivity extends FragmentActivity {
private DrawerLayout DrawerLayout;
private ListView DrawerList;
private ActionBarDrawerToggle DrawerToggle;
@SuppressWarnings("unused")
private CharSequence DrawerTitle;
private CharSequence Title;
private String[] ListTitles;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.drawerlist_test);
Title = DrawerTitle = getTitle();
ListTitles = getResources().getStringArray(R.array.list_array);
DrawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);
DrawerList = (ListView) findViewById(R.id.left_drawer);
// initialize drawer list
// Also set a custom shadow that overlays the main content when the drawer opens
DrawerLayout.setDrawerShadow(R.drawable.drawer_shadow, GravityCompat.START);
// add fragments to drawer list
Fragment newFragment;
FragmentTransaction transaction = getFragmentManager().beginTransaction();
newFragment = new testfragment();
transaction.replace(R.id.left_drawer, newFragment);
transaction.addToBackStack(null);
transaction.commit();
System.out.println("check1........ + fragment created");
/*
// set up the drawer's list view with items and click listener
DrawerList.setAdapter(new ArrayAdapter<String>(this, R.layout.drawer_itemlist, ListTitles));
DrawerList.setOnItemClickListener(new DrawerItemClickListener());
*/
// enable ActionBar app icon to behave as action to toggle nav drawer
getActionBar().setDisplayHomeAsUpEnabled(true);
getActionBar().setHomeButtonEnabled(true);
// ActionBarDrawerToggle ties together the the proper interactions
// between the sliding drawer and the action bar app icon
DrawerToggle = new ActionBarDrawerToggle(
this, /* host Activity */
DrawerLayout, /* DrawerLayout object */
R.drawable.ic_drawer, /* nav drawer image to replace 'Up' caret */
R.string.drawer_open, /* "open drawer" description for accessibility */
R.string.drawer_close /* "close drawer" description for accessibility */
) {
public void onDrawerClosed(View view) {
getActionBar().setTitle(Title);
invalidateOptionsMenu(); // creates call to onPrepareOptionsMenu()
}
public void onDrawerOpened(View drawerView) {
getActionBar().setTitle(Title); // same title for open/close drawer
//getActionBar().setTitle(DrawerTitle);
invalidateOptionsMenu(); // creates call to onPrepareOptionsMenu()
}
};
DrawerLayout.setDrawerListener(DrawerToggle);
if (savedInstanceState == null) {
selectItem(0);
}
}
/**
* When using the ActionBarDrawerToggle, you must call it during
* onPostCreate() and onConfigurationChanged()...
*/
@Override
protected void onPostCreate(Bundle savedInstanceState) {
super.onPostCreate(savedInstanceState);
// Sync the toggle state after onRestoreInstanceState has occurred.
DrawerToggle.syncState();
}
@Override
public void onConfigurationChanged(Configuration newConfig) {
super.onConfigurationChanged(newConfig);
// Pass any configuration change to the drawer toggle
DrawerToggle.onConfigurationChanged(newConfig);
}
// option menu - action bar
@Override
public boolean onCreateOptionsMenu(Menu menu) {
MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.main, menu);
return super.onCreateOptionsMenu(menu);
}
// Called whenever we call invalidateOptionsMenu()
@Override
public boolean onPrepareOptionsMenu(Menu menu) {
// If the nav drawer is open, hide action items related to the content view
boolean drawerOpen = DrawerLayout.isDrawerOpen(DrawerList);
menu.findItem(R.id.action_websearch).setVisible(!drawerOpen);
return super.onPrepareOptionsMenu(menu);
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// The action bar home/up action should open or close the drawer.
// ActionBarDrawerToggle will take care of this.
if (DrawerToggle.onOptionsItemSelected(item)) {
return true;
}
// Handle action buttons
switch(item.getItemId()) {
case R.id.action_websearch:
// create intent to perform web search for this planet
Intent intent = new Intent(Intent.ACTION_WEB_SEARCH);
intent.putExtra(SearchManager.QUERY, getActionBar().getTitle());
// catch event that there's no activity to handle intent
if (intent.resolveActivity(getPackageManager()) != null) {
startActivity(intent);
} else {
Toast.makeText(this, R.string.app_not_available, Toast.LENGTH_LONG).show();
}
return true;
default:
return super.onOptionsItemSelected(item);
}
}
// Nav Drawer List click
// The click listener for ListView in the navigation drawer
private class DrawerItemClickListener implements ListView.OnItemClickListener {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
selectItem(position);
}
}
private void selectItem(int position) {
Fragment newFragment;
FragmentTransaction transaction = getFragmentManager().beginTransaction();
switch (position) {
case 0:
newFragment = new f1();
transaction.replace(R.id.content_frame, newFragment);
transaction.addToBackStack(null);
transaction.commit();
break;
case 1:
newFragment = new f2();
transaction.replace(R.id.content_frame, newFragment);
transaction.addToBackStack(null);
transaction.commit();
break;
case 2:
newFragment = new f3();
transaction.replace(R.id.content_frame, newFragment);
transaction.addToBackStack(null);
transaction.commit();
break;
case 3:
newFragment = new f4();
transaction.replace(R.id.content_frame, newFragment);
transaction.addToBackStack(null);
transaction.commit();
break;
}
DrawerList.setItemChecked(position, true);
setTitle(ListTitles[position]);
DrawerLayout.closeDrawer(DrawerList);
}
@Override
public void setTitle(CharSequence title) {
Title = title;
getActionBar().setTitle(Title);
}
}
And this is the logcat error list :
11-24 13:16:53.058: E/Trace(18812): error opening trace file: No such file or directory (2)
11-24 13:16:53.058: W/Trace(18812): Unexpected value from nativeGetEnabledTags: 0
11-24 13:16:53.058: W/Trace(18812): Unexpected value from nativeGetEnabledTags: 0
11-24 13:16:53.058: W/Trace(18812): Unexpected value from nativeGetEnabledTags: 0
11-24 13:16:53.068: W/Trace(18812): Unexpected value from nativeGetEnabledTags: 0
11-24 13:16:53.068: W/Trace(18812): Unexpected value from nativeGetEnabledTags: 0
11-24 13:16:53.108: D/AndroidRuntime(18812): Shutting down VM
11-24 13:16:53.108: W/dalvikvm(18812): threadid=1: thread exiting with uncaught exception (group=0xb2e17908)
11-24 13:16:53.108: E/AndroidRuntime(18812): FATAL EXCEPTION: main
11-24 13:16:53.108: E/AndroidRuntime(18812): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.kodevelop.gndec/com.kodevelop.gndec.LaunchActivity}: java.lang.ClassCastException: android.widget.FrameLayout cannot be cast to android.widget.ListView
11-24 13:16:53.108: E/AndroidRuntime(18812): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2180)
11-24 13:16:53.108: E/AndroidRuntime(18812): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2230)
11-24 13:16:53.108: E/AndroidRuntime(18812): at android.app.ActivityThread.access$600(ActivityThread.java:141)
11-24 13:16:53.108: E/AndroidRuntime(18812): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1234)
11-24 13:16:53.108: E/AndroidRuntime(18812): at android.os.Handler.dispatchMessage(Handler.java:99)
11-24 13:16:53.108: E/AndroidRuntime(18812): at android.os.Looper.loop(Looper.java:137)
11-24 13:16:53.108: E/AndroidRuntime(18812): at android.app.ActivityThread.main(ActivityThread.java:5039)
11-24 13:16:53.108: E/AndroidRuntime(18812): at java.lang.reflect.Method.invokeNative(Native Method)
11-24 13:16:53.108: E/AndroidRuntime(18812): at java.lang.reflect.Method.invoke(Method.java:511)
11-24 13:16:53.108: E/AndroidRuntime(18812): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
11-24 13:16:53.108: E/AndroidRuntime(18812): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
11-24 13:16:53.108: E/AndroidRuntime(18812): at dalvik.system.NativeStart.main(Native Method)
11-24 13:16:53.108: E/AndroidRuntime(18812): Caused by: java.lang.ClassCastException: android.widget.FrameLayout cannot be cast to android.widget.ListView
11-24 13:16:53.108: E/AndroidRuntime(18812): at com.kodevelop.gndec.LaunchActivity.onCreate(LaunchActivity.java:42)
11-24 13:16:53.108: E/AndroidRuntime(18812): at android.app.Activity.performCreate(Activity.java:5104)
11-24 13:16:53.108: E/AndroidRuntime(18812): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1080)
11-24 13:16:53.108: E/AndroidRuntime(18812): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2144)
11-24 13:16:53.108: E/AndroidRuntime(18812): ... 11 more
I'm willing to share the whole code in zipped format so as to import the project in your system, if need arises.
回答1:
You are trying to get the ID of a framelayout but casting it as listview
DrawerList = (ListView) findViewById(R.id.left_drawer);
which should actually be
DrawerList = (FrameLayout) findViewById(R.id.left_drawer);
来源：https://stackoverflow.com/questions/20175476/load-navigation-drawer-slider-with-dynamic-fragments