问题
I'm building an Android application using ListView. I have list view items as show below.
^ List Item Index 0
^ List Item Index 1
The xlm is as follows.
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:padding="4dip" >
<ImageView
android:id="@+id/icon"
android:layout_width="wrap_content"
android:layout_height="fill_parent"
android:src="@drawable/icon" />
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="fill_parent"
android:layout_weight="0.93"
android:orientation="vertical"
android:padding="10dp"
android:paddingLeft="10dp"
android:paddingRight="10dp" >
<!-- JFN bottom used to be 2, top 6 -->
<!-- Name Label -->
<TextView
android:id="@+id/name"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:paddingBottom="0dip"
android:paddingTop="0dip"
android:textColor="#43bd00"
android:textSize="16sp"
android:textStyle="bold" />
<!-- Email label -->
<TextView
android:id="@+id/email"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:paddingBottom="0dip"
android:textColor="#acacac" />
<!-- Mobile number label -->
<TextView
android:id="@+id/mobile"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:gravity="left"
android:text="Mobile: "
android:textColor="#5d5d5d"
android:textStyle="bold" />
</LinearLayout>
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:gravity="right"
android:orientation="vertical" >
<ImageView
android:id="@+id/chat"
android:layout_width="wrap_content"
android:layout_height="fill_parent"
android:layout_marginRight="2dip"
android:gravity="right"
android:src="@drawable/chat" />
<ImageView
android:id="@+id/calendar"
android:layout_width="wrap_content"
android:layout_height="fill_parent"
android:layout_marginRight="2dip"
android:gravity="right"
android:src="@drawable/calendar" />
</LinearLayout>
</LinearLayout>
I'm trying to detect four different click events:
- When the picture of the dog is clicked
- When the middle section is clicked
- When the chat button is clicked
- When the calendar button is clicked
In addition, each of these clicks must be distinguishable based on which item in the ListView has been clicked.
I know how I can tell each ListItem apart: I can use the ListView.setOnItemClickListener as is shown below, which provides an id of the item in the list. But this does not tell me which of the four portions was clicked on.
ListView lv = getListView();
// Listview on item click listener
lv.setOnItemClickListener(new OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
// getting values from selected ListItem
Log.d("JFN","List item clicked with id: "+id);
}
});
I can also bind a different onClick function call to each of the four sections in the xml, but this doesn't let me know which of the list items was clicked.
android:onClick="imgClicked"
I don't think I can combine these two solutions, as it would introduce a race condition. Is there a proper way to accomplish detecting both which list item was clicked, and which part of that particular list item was clicked?
Further Info
The following code shows my creation of the ListView using the adapter.
// Retrieve string, convert to JSON, and extract contacts
String jsonData = jsonToStringFromAssetFolder("maemployees.json",this);
JSONObject jsonObj = new JSONObject(jsonData).getJSONObject(TAG_RESULTS);
int numContacts = jsonObj.getInt(TAG_NUM);
Log.d("JFN","Number of contacts stated: "+numContacts);
contacts = jsonObj.getJSONArray(TAG_CONTACTS);
Log.d("JFN","Number of contacts present: "+contacts.length());
// Loop over contacts
for( int i=0; i<contacts.length(); i++) {
// Extract this one
JSONObject c = contacts.getJSONObject(i);
// Extract strings
String first = (c.has(TAG_FIRST)) ? c.getString(TAG_FIRST) : "";
String last = (c.has(TAG_LAST)) ? c.getString(TAG_LAST) : "";
String city = (c.has(TAG_CITY)) ? c.getString(TAG_CITY) : "";
String state = (c.has(TAG_STATE)) ? c.getString(TAG_STATE) : "";
String country = (c.has(TAG_COUNTRY)) ? c.getString(TAG_COUNTRY) : "";
String costName = (c.has(TAG_COST_NAME)) ? c.getString(TAG_COST_NAME) : "";
// Temporary hash map for single contact
HashMap<String, String> contact = new HashMap<String, String>();
contact.put("name", first+" "+last);
contact.put("email", city+", "+state+", "+country);
contact.put("mobile", costName);
// Adding single contact to list
contactList.add(contact);
}
Log.d("JFN","Done looping contacts");
//Updating parsed JSON data into ListView
ListAdapter adapter = new SimpleAdapter(
MainActivity.this, contactList,
R.layout.list_item, new String[] { "name", "email",
"mobile" }, new int[] { R.id.name,
R.id.email, R.id.mobile });
setListAdapter(adapter);
回答1:
Allright I was having a similar kind of problem but i was using a ViewPager with a ListFragment and a custom ListView Layout.
In the above case you are using just ImageViews, but just in case if you use controls like ImageButton, CheckBox ,Button etc then you would face problems discussed here and here.
This is simply because such controls can steal focus from the ListView and the complete list item cant be selected/clicked. so I would say that just using ImageViews is a smart move.
I am assuming that you are using an Adapter to set the content of your list. Inside that adapter you can assign onClickListener()s for each item like this:
public class MyListAdapter extends ArrayAdapter<String>{
.......
@Override
public View getView(int position, View convertView, ViewGroup parent) {
View rowView=inflator.inflate(R.layout.channel_list_item, null, true);
ImageView chat=(ImageView) rowView.findViewById(R.id.chat);
chat.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
//do something
}
}
ImageView calendar=(ImageView) rowView.findViewById(R.id.calendar);
calendar.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
//do something
}
}
.......
}
}
but remember that while using controls like ImageButton, CheckBox ,Button you need to assign property android:focusable="false" in the XML. and for the ImageButton you need to do this inside the getView() method:
final ImageButton imgBtn=(ImageButton) rowView.findViewById(R.id.imgBtn);
imgBtn.setFocusable(false);
imgBtn.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
//do your task here
}
});
or you can also use Nathaniel Waggoner's approach.
Hope I answered your question.
回答2:
You must be setting the content of your list view in an Adapter, So inside the adapter, there is a method getView(). Inside that getView() define each of your view and then set onCLickListener inside those view.
For Ex:
dog.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
//operation to be performed.
}
});
similarly apply onCLickListeners() to all other views.
回答3:
If you don't want to set on click listeners for each item, the other option is to compare the view.getId() value of the view passed into on click, to the ids of the views, something like:
switch(view.getId()){
case(R.id.dog_image):
//do stuff
break;
case(R.id.other_image):
//do stuff
break;
}
Otherwise you can do this programatically by doing the following in onCreate:
.....
setContentView(myView);
ImageView dogImage = (ImageView) findViewById(R.id.dog_image);
dogImage.setOnClickListener(new View.OnClickListener {
@Override
public void onClick(View v) {
// do stuff...
}
})
....
来源：https://stackoverflow.com/questions/21421821/how-to-sense-what-has-been-clicked-within-an-android-list-view-element