尝试在 DrawerLayout 中创建具有可扩展列表的应用程序。只需从 strings.xml 中的数组中拉出列表，我的 DrawerLayout 就可以正常工作。
自从我添加 ExpandableListAdapter 以来，尽管它一直在崩溃，或者即使它运行它也不让我做任何事情。
这是我的代码：
package com.alpha.omegaRSS;
import java.util.ArrayList;
import android.app.Activity;
import android.os.Bundle;
import android.support.v4.app.ActionBarDrawerToggle;
import android.support.v4.view.GravityCompat;
import android.support.v4.widget.DrawerLayout;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.ExpandableListView;
public class MainActivity extends Activity {
private DrawerLayout navDrawerLayout;
private ActionBarDrawerToggle navDrawerToggle;
//private ListView navDrawerList;
private CharSequence navDrawerTitle;
private CharSequence navTitle;
private String[] leftItems;
private ExpandableListView navDrawerList;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
navTitle=navDrawerTitle=getTitle();
//leftItems = getResources().getStringArray(R.array.left_drawer_array);
navDrawerLayout=(DrawerLayout) findViewById(R.id.nav_layout);
//navDrawerList= (ListView) findViewById(R.id.left_drawer);
navDrawerList=(ExpandableListView)findViewById(R.id.left_drawer);
ArrayList<Parent> arrayParents = new ArrayList<Parent>();
ArrayList<String> arrayChildren = new ArrayList<String>();
//here we set the parents and the children
for (int i = 0; i < 10; i++){
//for each "i" create a new Parent object to set the title and the children
Parent parent = new Parent();
parent.setTitle("Parent " + i);
arrayChildren = new ArrayList<String>();
for (int j = 0; j < 10; j++) {
arrayChildren.add("Child " + j);
}
parent.setArrayChildren(arrayChildren);
//in this array we add the Parent object. We will use the arrayParents at the setAdapter
arrayParents.add(parent);
}
// set a custom shadow that overlays the main content when the drawer opens
navDrawerLayout.setDrawerShadow(R.drawable.drawer_shadow, GravityCompat.START);
//set up the drawer's list view with items and click listener
navDrawerList.setAdapter(new ArrayAdapter<String>(this, R.layout.drawer_list_item, leftItems));
// HERE I AM navDrawerList.setAdapter(new CustomListAdapter(MainActivity.this, arrayParents));
//navDrawerList.setOnItemClickListener(new DrawerItemClickListener());
// enable ActionBar app icon to behave as action to toggle nav drawer
getActionBar().setDisplayHomeAsUpEnabled(true);
getActionBar().setHomeButtonEnabled(true);
navDrawerToggle=new ActionBarDrawerToggle(this, navDrawerLayout, R.drawable.ic_drawer, R.string.drawer_open, R.string.drawer_close)
//called when the drawer is completely closed
{
public void onDrawerClosed(View mainView) {
getActionBar().setTitle(navTitle);
invalidateOptionsMenu();
}
public void onDrawerOpened(View drawerView) {
getActionBar().setTitle(navDrawerTitle);
invalidateOptionsMenu();
}
};
navDrawerLayout.setDrawerListener(navDrawerToggle);
/*
//swiping controller
@Override
public boolean dispatchTouchEvent(MotionEvent event) {
super.dispatchTouchEvent(event);
return gestureDetector.onTouchEvent(event);
}
SimpleOnGestureListener simpleOnGestureListener = new SimpleOnGestureListener() {
@Override
public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,
float velocityY) {
float sensitvity = 50;
if ((e1.getX() - e2.getX()) > sensitvity) {
SwipeLeft();
} else if ((e2.getX() - e1.getX()) > sensitvity) {
SwipeRight();
}
return true;
}
};
GestureDetector gestureDetector = new GestureDetector(this,
simpleOnGestureListener);
*/
}
/* if(savedInstanceState==null){
selectItem(0);
}*/
@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;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Pass the event to ActionBarDrawerToggle, if it returns
// true, then it has handled the app icon touch event
if (navDrawerToggle.onOptionsItemSelected(item)) {
return true;
}
// Handle your other action bar items...
return super.onOptionsItemSelected(item);
}
/*private void SwipeLeft() {
navDrawerLayout.closeDrawer(Gravity.RIGHT);
}
private void SwipeRight() {
navDrawerLayout.openDrawer(Gravity.LEFT);
}
*/
}
这是我的 ExpandedlistAdapter 类。
package com.alpha.omegaRSS;
import java.util.ArrayList;
import android.content.Context;
import android.database.DataSetObserver;
import android.view.LayoutInflater;
Import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseExpandableListAdapter;
import android.widget.Button;
import android.widget.TextView;
public class CustomListAdapter extends BaseExpandableListAdapter {
private LayoutInflater inflater;
private ArrayList<Parent> mParent;
public CustomListAdapter(Context context, ArrayList<Parent> parent){
mParent = parent;
inflater = LayoutInflater.from(context);
}
@Override
//counts the number of group/parent items so the list knows how many times calls getGroupView() method
public int getGroupCount() {
return mParent.size();
}
@Override
//counts the number of children items so the list knows how many times calls getChildView() method
public int getChildrenCount(int i) {
return mParent.get(i).getArrayChildren().size();
}
@Override
//gets the title of each parent/group
public Object getGroup(int i) {
return mParent.get(i).getTitle();
}
@Override
//gets the name of each item
public Object getChild(int i, int i1) {
return mParent.get(i).getArrayChildren().get(i1);
}
@Override
public long getGroupId(int i) {
return i;
}
@Override
public long getChildId(int i, int i1) {
return i1;
}
@Override
public boolean hasStableIds() {
return true;
}
@Override
//in this method you must set the text to see the parent/group on the list
public View getGroupView(int i, boolean b, View view, ViewGroup viewGroup) {
ViewHolder holder = new ViewHolder();
holder.groupPosition = i;
if (view == null) {
view = inflater.inflate(R.id.left_drawer, viewGroup,false);
}
TextView textView = (TextView) view.findViewById(R.layout.list_item_parent);
//"i" is the position of the parent/group in the list
textView.setText(getGroup(i).toString());
view.setTag(holder);
//return the entire view
return view;
}
@Override
//in this method you must set the text to see the children on the list
public View getChildView(int i, int i1, boolean b, View view, ViewGroup viewGroup) {
ViewHolder holder = new ViewHolder();
holder.childPosition = i1;
holder.groupPosition = i;
if (view == null) {
view = inflater.inflate(R.layout.drawer_list_item, viewGroup,false);
}
TextView textView = (TextView) view.findViewById(R.id.child_item);
//"i" is the position of the parent/group in the list and
//"i1" is the position of the child
textView.setText(mParent.get(i).getArrayChildren().get(i1));
view.setTag(holder);
//return the entire view
return view;
}
@Override
public boolean isChildSelectable(int i, int i1) {
return true;
}
@Override
public void registerDataSetObserver(DataSetObserver observer) {
/* used to make the notifyDataSetChanged() method work */
super.registerDataSetObserver(observer);
}
/* @Override
public void onClick(View view) {
ViewHolder holder = (ViewHolder)view.getTag();
if (view.getId() == holder.button.getId()){
// DO SOMETHING
}
}*/
protected class ViewHolder {
protected int childPosition;
protected int groupPosition;
protected Button button;
}
}