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(Android) How to set hyperlink to a textview inside ListView?

I have a listview containing some news. Each news is a row which comtains a title, content, publisher and date. Now I want to set hyperlinks to every title TextView. How to implement that? The following is my code:
private void show_news() {
ArrayList<Map<String, Object>> list = new ArrayList<>();
get_data(list);
ListView lv = (ListView) findViewById(R.id.News_List);
SimpleAdapter adp = new SimpleAdapter(getApplicationContext(), list, R.layout.news_item, new String[]{"news_title", "news_content", "news_publisher", "news_date"}, new int[]{R.id.news_title, R.id.news_content, R.id.news_publisher, R.id.news_date});
lv.setAdapter(adp);
/* the code above runs properly*/
/*Now I want to set hyperlink to my title TextView..*/
}
This is my news_item.xml:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<TextView
android:id="#+id/news_title"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginBottom="5dp"
android:layout_marginTop="5dp"
android:textColor="#000000"
android:textSize="25sp" />
<TextView
android:id="#+id/news_content"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginBottom="5dp"
android:textSize="18sp" />
<TextView
android:id="#+id/news_publisher"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginBottom="5dp"
android:textSize="12sp" />
<TextView
android:id="#+id/news_date"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textSize="12sp" />
</LinearLayout>
I am new to Android programming. Can anyone help me with this? Thanks a lot!

LinearLayout first = (LinearLayout) adp.getView(0, null, lv);
TextView title = (TextView)first.getChildAt(0);
That doesn't necessarily get the first element of the list view. It doesn't even necessarily get the first element on screen. That's very implementation specific (you're assuming the list view doesn't have any children other than its rows, which is actually wrong in many cases).
If you want to change the first item of a list view, do
Item item = adb.getItem(0)
item.title= "New Title"
adp.notifyDataSetChanged();

You can extend the SimpleAdapter and use the derived adapter. When you extend the adapter, set the hyperlink property for the title by calling:
<the title textview>.setAutoLinkMask(Linkify.WEB_URLS);
in the method getView method of the adapter. A commonly used approach in Android ListView adapter is to use a so called view holder, which is a key technique to get better listview performance, and you can check the details from the developer document: Hold View Objects in a View Holder
Suppose you employ this approach, the code would looks more or less like:
holder.titleView.setAutoLinkMask(Linkify.WEB_URLS);
If your textview does not have a URL, then you can set the text in HTML form as:
holder.titleView.setText(
Html.fromHtml(
"Breaking News "));
holder.titleView.setMovementMethod(LinkMovementMethod.getInstance());

Android LinearLayout populate children from database

I have a HorizontalScollView. It has a LinearLayout child. How do I populate the linear layout with children created based on content from a database since I can't bind a SimpleCursorAdapter to it (obviously)?
I've tried:
SimpleCursorAdapter summaryItems = new SimpleCursorAdapter(this, R.layout.summary_item, summaryItemsCursor, from, to);
int count = summaryItems.getCount();
View new_view;
for (int i = 0; i < count; i++) {
new_view = (summaryItems.newView(this, summaryItemsCursor, mNewsContainer));
mNewsContainer.addView(new_view);
}
I was hoping that the view returned by the SimpleCursorAdapter.newView() would be usable, but apparently not. I'm quite new to android and completely lost as to the right way to do this.
XML's for reference:
<HorizontalScrollView android:id="#+id/news_gallery"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<LinearLayout android:id="#+id/news_container"
android:orientation="horizontal"
android:layout_height="wrap_content"
android:layout_width="wrap_content"
>
</LinearLayout>
</HorizontalScrollView>
and summary_item
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/news_gallery_item"
android:layout_marginRight="#dimen/news_gallery_item_spacing"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
<ImageView android:id="#+id/news_gallery_item_image"
android:adjustViewBounds="true"
android:maxHeight="#dimen/news_gallery_image_height"
android:layout_width="wrap_content"
android:layout_height="wrap_content"/>
<TextView android:id="#+id/news_gallery_item_tagline"
style="#style/news_gallery_text_container"
android:layout_width="match_parent"
android:layout_height="wrap_content"/>
</FrameLayout>

This sounds (and somehow looks) like you'll want to use a ListView. A tutorial might be found here.
To populate the ListView, you can then use a SimpleCursorAdapter.
Since you need it horizontally, you can use the HorizonatalListView-class, which is a user-created extension to a normal ListView (so you can use all it's methods). The corresponding question can be found here.

A ViewBinder with an Inflater on your item view should do the trick

Display "No Item" message in ListView

I've created some composie UIs in my android apps and there are some ListView controls -among other controls- inside a view. Because of this, I have used "Activity" as my activity base class.
Now I need to display a simple message like "No Item" when the ListView that is bound to my adapter is empty. I know this is possible when using ListActivity but I'm not sure what's the best approach for this?

You can have an empty view without a ListActivity! The correct method is as follows
First add an 'empty view' to your layout XML below your list
...
<ListView
android:id="#+id/list"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
/>
<TextView
android:id="#+id/empty"
android:text="Empty"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:gravity="center"
/>
...
Next override the onContentChanged method of your activity and set the empty view of your list to your empty view:
#Override
public void onContentChanged() {
super.onContentChanged();
View empty = findViewById(R.id.empty);
ListView list = (ListView) findViewById(R.id.list);
list.setEmptyView(empty);
}
That's it! Android will take care of hiding/showing the list and empty view when you update the adapter.
The Magic
Deciding whether the empty view is shown or not is handled by the superclass of ListView, AdapterView. AdapterView registers a DataSetObserver on the set adapter so it is notified whenever the data is changed. This triggers a call to checkFocus in AdapterView which contains the following lines
if (mEmptyView != null) {
updateEmptyStatus((adapter == null) || adapter.isEmpty());
}
and sets the empty view visibility based on whether the adapter is empty or not.

You're looking for the empty view of a ListActivity:
ListActivity
If you're using ListView you can use the method setEmptyView():
setEmptyView

Just combine your ListView with TextView:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<ListView
android:id="#+id/list"
android:layout_height="fill_parent"
android:layout_width="fill_parent" />
<TextView
android:id="#+id/list_empty"
android:text="No Item"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"/>
</LinearLayout>
Then check the count of items an chanche visibility on ListView accordingly:
ListView lv = (ListView)findViewById(R.id.list);
lv.setVisibility((adapter.isEmpty())?View.GONE:View.VISIBLE);
If you are using Custom Adapter, you can do this in the overridden notifyDataSetChanged method.

You can use Toast Message for this..
Check the Count of the Adapter value by adapter.getCount()
if(Adapter.getCount()!=0){
List.setAdapter(Adapter);
}else{
Toast.makeText(YourActivityName.this, "No Items Available",Toast.LENGTH_SHORT).show();
}

For the layout code by Joseph, you need to edit the #+id/list and #+id/empty to #android:id/*, like:
<ListView
android:id="#android:id/list"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
/>
<TextView
android:id="#android:id/empty"
android:text="Empty"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:gravity="center"
/>
This way, you even don't need to override the onContentChanged() function.

The easiest way to achieve this was using a ListFragment instead of a ListActivity. ListFragment has the following convenience method:
setEmptyText("My no items message...");
Besides, using a ListFragment class has other advantages. For example, the possibility to combine it with the new AppCompat library (which you cannot do with ListActivity because you have to extend from ActionBarActivity).

Custom Listview Adapter, adding a static footer, and understanding R.id.list

There is something I'm just not getting, and I'm looking for assistance in understanding what is happening here.
I have a custom list adapter (that just extends BaseAdapter) that I have successfully been using to generate and display a list. Now I want to add a static footer to the bottom of my list. After looking at a number of resources (specifically this one) I've come to realize that my reluctance of using XML has to come to an end, and set up the following xml layout in a file called devices_list.xml:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content" android:layout_height="wrap_content"
android:orientation="vertical">
<LinearLayout android:id="#+id/bottom_control_bar"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true">
<ToggleButton android:id="#+id/bottom_control_toggle"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:textOff="Filter Favourites OFF"
android:textOn="Filter Favourites ON"/>
</LinearLayout>
<ListView android:id="#android:id/list"
android:layout_width="fill_parent"
android:layout_height="0dip"
android:layout_above="#id/bottom_control_bar">
</ListView>
<TextView android:id="#android:id/empty"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/main_empty_list"
android:layout_above="#id/bottom_control_bar"/>
</RelativeLayout>
After some adjustments to the activity that holds the list, I ran the code. I see my footer, (and also the tab widget which is parent to everything), but the area where the list goes is empty.
#Override
public void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
this.setContentView(R.layout.devices_list);
db = new DbManager(this);
db.open();
AllCur = db.fetchAllDevices();
startManagingCursor(AllCur);
list = new DeviceListAdapter(this, AllCur); //make my custom list adapter
setListAdapter(list);
}
Is there some way to link up the ListView widget declared in my xml with my DeviceListAdapter? It's pretty clear to me now that I'm not entirely sure about how this is all working. Any help in clarification would be much appreciated.

You have both the ListView and the TextView set to android:layout_above="#id/bottom_control_bar", which means the TextView will overlap the ListView. And, you have said that your ListView height is 0dip, which will make for an extremely short list.
I would define the ListView as being above the TextView and anchored to the top of the screen (android:layout_alignParentTop="true").
Is there some way to link up the
ListView widget declared in my xml
with my DeviceListAdapter?
You already are, by calling setListAdapter().

Android: failed to setContentView when switching to ListActivity

[update] I got the error, which says "Your content must have a ListView whose id attribute is 'android.R.id.list'". Appearently nothing in my xml is ListView. But is that required?
This is an follow-up issue on my previous question
android: which view should I use for showing text and image?
I read the article about creating ListView for LinearLayout. However, my following code failed at the setContentView() function when I changed "extends Activity" to "extends ListActivity", any idea why?
private TextView mSelection;
//private ImageView mImages;
static final String[] keywords = new String[]{"China", "Japan", "USA", "Canada"};
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.contactLayout);
mSelection = (TextView)findViewById(R.id.ContactNames);
ArrayAdapter adapter = new ArrayAdapter<String>(this, R.layout.contactlayout, R.id.ContactNames,keywords);
setListAdapter(adapter);
}
My Layout is from this article: http://www.curious-creature.org/2009/02/22/android-layout-tricks-1/
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="?android:attr/listPreferredItemHeight"
android:padding="6dip">
<ImageView
android:id="#+id/icon"
android:layout_width="wrap_content"
android:layout_height="fill_parent"
android:layout_marginRight="6dip"
android:src="#drawable/icon" />
<LinearLayout
android:orientation="vertical"
android:layout_width="0dip"
android:layout_weight="1"
android:layout_height="fill_parent">
<TextView
android:id="#+id/ContactNames"
android:layout_width="fill_parent"
android:layout_height="0dip"
android:layout_weight="1"
android:gravity="center_vertical"
android:text="My Application" />
<TextView
android:layout_width="fill_parent"
android:layout_height="0dip"
android:layout_weight="1"
android:singleLine="true"
android:ellipsize="marquee"
android:text="Simple application that shows how to use RelativeLayout" />
</LinearLayout>

I think you misunderstood the other posts I showed you in the previous question. They were explaining how to use a custom layout for each row in your list, not how to define the entire layout file for the activity. You need something like this:
(main.xml)
<?xml version="1.0" encoding="utf-8"?>
<ListView xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:cacheColorHint="#00000000"
android:id="#android:id/list">
</ListView>
Note the very important line android:id="#android:id/list". You must have that in your ListView as that's what tells Android where your list is. The cacheColorHint is useful if your background isn't black - see this post for more details about that.
With the above lines you can give your activity a list that will be recognised properly. Here's a basic example:
public class TestProject extends ListActivity {
final static String[] ITEMS = {"blah", "floop", "gnarlp", "stuff"};
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,
R.layout.listrow, R.id.textview, ITEMS);
setListAdapter(adapter);
}
}
Then the listrow layout is just this:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
<TextView android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/textview"/>
</LinearLayout>
This is a really simple layout. If you want to get something more complicated, changes are you'll have to use a BaseAdapter, as that gives you calls getView(...) before each row. In that you can use different layouts depending on the contents of each row. However, BaseAdapter looks scary when you first try it, so be warned! :)

Yes, if you are using a ListActivity, you need to have a ListView who's id is android.R.list in your layout file.
If you aren't using a ListView in your layout, and I don't see one in there, then switch to using a regular Activity.

Actually, your (custom) layout doesn't need a ListView when using a list activity. The easy way to solve this is just remove the setContentView() line altogether. In simple terms, when you do it, Android "assumes" the layout you're using to contain a single full-screen ListView, and provides it for you.
If you want a different (richer) interface for the Activity though, you must code the XML and use the informed ID for Android to know how to show the list implied by the activity being a ListActivity after all. Note that the layout for an item isn't the same as the list, and although I haven't tried that, I assume you can have a custom item layout without having an explicit ListView in the activity layout.