How to make child of expandable list clickable and do something?

Question

Hi just wondering how I can make a listener or sorts. I wanna make it so when one of the childs are click it opens google naviagtion. I have this code to do that.

Intent i = new Intent(Intent.ACTION_VIEW,
Uri.parse("google.navigation:q=Hemsworth+Pontefract"));
startActivity(i);

But how do I make the child listen for a click?

ExpandableList Code

package com.sammy.umass;

import android.app.ExpandableListActivity;
import android.os.Bundle;
import android.view.ContextMenu;
import android.view.Gravity;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.view.ContextMenu.ContextMenuInfo;
import android.widget.AbsListView;
import android.widget.BaseExpandableListAdapter;
import android.widget.ExpandableListAdapter;
import android.widget.ExpandableListView;
import android.widget.TextView;
import android.widget.Toast;
import android.widget.ExpandableListView.ExpandableListContextMenuInfo;


public class DirectionsScreenActivity extends ExpandableListActivity {
ExpandableListAdapter mAdapter;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    // Set up our adapter
    mAdapter = new MyExpandableListAdapter();
    setListAdapter(mAdapter);
    registerForContextMenu(getExpandableListView());
}

@Override
public void onCreateContextMenu(ContextMenu menu, View v, ContextMenuInfo menuInfo) {
    menu.setHeaderTitle("Sample menu");
    menu.add(0, 0, 0, R.string.expandable_list_sample_action);
}

@Override
public boolean onContextItemSelected(MenuItem item) {
    ExpandableListContextMenuInfo info = (ExpandableListContextMenuInfo) item.getMenuInfo();

    String title = ((TextView) info.targetView).getText().toString();

    int type = ExpandableListView.getPackedPositionType(info.packedPosition);
    if (type == ExpandableListView.PACKED_POSITION_TYPE_CHILD) {
        int groupPos = ExpandableListView.getPackedPositionGroup(info.packedPosition); 
        int childPos = ExpandableListView.getPackedPositionChild(info.packedPosition); 
        Toast.makeText(this, title + ": Child " + childPos + " clicked in group " + groupPos,
                Toast.LENGTH_SHORT).show();
        return true;
    } else if (type == ExpandableListView.PACKED_POSITION_TYPE_GROUP) {
        int groupPos = ExpandableListView.getPackedPositionGroup(info.packedPosition); 
        Toast.makeText(this, title + ": Group " + groupPos + " clicked", Toast.LENGTH_SHORT).show();
        return true;
    }

    return false;
}

/**
 * A simple adapter which maintains an ArrayList of photo resource Ids. 
 * Each photo is displayed as an image. This adapter supports clearing the
 * list of photos and adding a new photo.
 *
 */
public class MyExpandableListAdapter extends BaseExpandableListAdapter {
    // Sample data set.  children[i] contains the children (String[]) for groups[i].
    private String[] groups = { "   Academic Buildings", "   Residential Buildings", "   Dining Commons", "   All Buildings A-Z" };
    private String[][] children = {
            { "Agricultural Engineering Bldg", "Army ROTC Bldg", "Arnold House", "(Studio) Arts Building" },
            { "Baker Hall", "Brett Hall", "Brooks Hall", "Brown Hall" },
            { "Berkshire", "Franklin","Hampden","Hampshire","Worcester" },
            { "Agricultural Engineering Bldg", "Army ROTC Bldg", "Arnold House", "(Studio) Arts Building" }
    };

    public Object getChild(int groupPosition, int childPosition) {
        return children[groupPosition][childPosition];
    }

    public long getChildId(int groupPosition, int childPosition) {
        return childPosition;
    }

    public int getChildrenCount(int groupPosition) {
        return children[groupPosition].length;
    }

    public TextView getGenericView() {
        // Layout parameters for the ExpandableListView
        AbsListView.LayoutParams lp = new AbsListView.LayoutParams(
                ViewGroup.LayoutParams.MATCH_PARENT, 64);

        TextView textView = new TextView(DirectionsScreenActivity.this);
        textView.setLayoutParams(lp);
        // Center the text vertically
        textView.setGravity(Gravity.CENTER_VERTICAL | Gravity.LEFT);
        // Set the text starting position
        textView.setPadding(36, 0, 0, 0);
        return textView;
    }

    public View getChildView(int groupPosition, int childPosition, boolean isLastChild,
            View convertView, ViewGroup parent) {
        TextView textView = getGenericView();
        textView.setText(getChild(groupPosition, childPosition).toString());
        return textView;
    }

    public Object getGroup(int groupPosition) {
        return groups[groupPosition];
    }

    public int getGroupCount() {
        return groups.length;
    }

    public long getGroupId(int groupPosition) {
        return groupPosition;
    }

    public View getGroupView(int groupPosition, boolean isExpanded, View convertView,
            ViewGroup parent) {
        TextView textView = getGenericView();
        textView.setText(getGroup(groupPosition).toString());
        return textView;
    }

    public boolean isChildSelectable(int groupPosition, int childPosition) {
        return true;
    }

    public boolean hasStableIds() {
        return true;
    }



}
}

Thanks!

Answer 1

You need to modify your getChildView funciton like so:

public View getChildView(int groupPosition, int childPosition, boolean isLastChild,
        View convertView, ViewGroup parent) {
    TextView textView = getGenericView();
    textView.setText(getChild(groupPosition, childPosition).toString());
    textView.setOnClickListener(new View.OnClickListener(){
      public void onClick(View view){
        Uri uriToOpen = getUriForView(groupPosition, childPosition);
        Intent i = new Intent(Intent.ACTION_VIEW, uriToOpen);
        startActivity(i);
      });

    return textView;
}

Since you want the uri to depend on the view itself, you can just write a little function that, based on the view's group position and child position, returns the appropriate uri.

Also, you should try to reuse the convertView in your get child view if possible. This will prevent the device from needing to do excess garbage collection. It just makes your app run smoother. Checkout this video for a further explanation.