Develop Reference

Android : put listfragment inside xml layout

ListFragment by defaults shows a progressbar while the data get loaded. I plan on putting the listfragment in xml file and have it show progressbar till I get the data from the server.
The reason I m trying to put listfragment inside xml is because in my layout I have a linearlayout above the place where I plan to put listfragment.
Here is my xml file.
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
>
<LinearLayout
android:id="#+id/filterHolder"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="center"
android:background="#color/white"
>
<ToggleButton
android:id="#+id/filterToggleButton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#color/white"
android:textColor="#color/black"
android:textOff="#string/filterToggleButtonText"
android:textOn="#string/filterToggleButtonText"
android:drawableLeft="#drawable/filter_small"
/>
</LinearLayout>
<fragment
andorid:name="in.coupondunia.androidapp.testListFragment"
android:id="#+id/couponsByCategoryFragment"
android:layout_below="#id/filterHolder"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
/>
</RelativeLayout>

Have you tried using http://developer.android.com/reference/android/app/ListFragment.html#setListShown(boolean) with parameter true? From the docs it might work.

Start a activity like a "Dialog", by writing java code

I want to make a activity like a "Dialog", and I know two ways so far:
Way 1) In Android ApiDemos, it is implemented by adding the attribute to the activity like
android:theme="#android:style/Theme.Dialog">
The result is: the new Activity appears on top of the existing activity, that is what I want.
Way 2) I try to invoke setTheme(android.R.style.Theme_Dialog) in the Activity.onCreate(Bundle) method, and the new activity also appears, but the background is all black. This is not what I want. Code is as below:
super.onCreate(savedInstanceState);
setTheme(android.R.style.Theme_Dialog);
requestWindowFeature(Window.FEATURE_NO_TITLE);
setContentView(R.layout.selecte_date);
Can anybody tell me how to implement the effect by writing Java code?

The easiest way is to add a second layout in you xml which is a overlay of existing one.
then you can set the overlay to visible in your activity. So then you got multiple views in 1 activity.
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="#android:color/transparent" >
<LinearLayout
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_alignParentTop="true"
android:background="#android:color/transparent">
<ImageView
android:id="#+id/icon"
android:layout_width="fill_parent"
android:layout_height="wrap_content"/>
<TextView
android:id="#+id/title"
android:layout_width="fill_parent"
android:layout_height="fill_parent" />
</LinearLayout>
<LinearLayout
android:layout_alignParentTop="true"
android:id="#+id/overlay"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="#color/translucent_black"
android:visibility="false" >
</LinearLayout>
</RelativeLayout>

Creating XML Layout file composed from other XML files?

I know this can seem a weird question but for me it would be really handy if I could compose a layout XML from a set of other xml files pointed by the main XML file. The reason is that I have some list item views defined in this xml and would like to reuse then in other places. Is it possible or the only way to do it is just Coping and pasting it?

You can include different layout files in a single layout using the 'include' tag
<LinearLayout>
<include layout="#layout/toinclude1" />
<include layout="#layout/toinclude1" />
</LinearLayout>
Another way is the ViewStub. If you want to load asynchronously your layout you can have:
<ViewStub android:id="#+id/stub"
android:inflatedId="#+id/subTree"
android:layout="#layout/mySubTree"
android:layout_width="120dip"
android:layout_height="40dip" />
And the in your code when you want you can write:
ViewStub stub = (ViewStub) findViewById(R.id.stub);
View inflated = stub.inflate();
For some reference: http://developer.android.com/reference/android/view/ViewStub.html

Say you have a header.xml like this
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
style="#style/somestyle" >
<ImageView
android:layout_width="wrap_content"
android:layout_height="fill_parent"
android:clickable="false"
android:paddingLeft="15dip"
android:scaleType="center"
android:src="#drawable/logo" />
</LinearLayout>
You can use <include layout="#layout/header"/> to include the header layout code in many layouts.
main.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/home_root"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<include layout="#layout/header"/>
</LinearLayout>

Fragment is good option. Here is an example: http://mobile.tutsplus.com/tutorials/android/android-sdk_fragments/
and document: http://developer.android.com/guide/components/fragments.html

Accessing Android views on nested layouts

I have trouble accessing Views from a layout that is included in another layout.
Please take a look at this picture:
http://dl.dropbox.com/u/3473245/layout_includes.png
How do I access the 4 text views programmatically?
Its probably something really simple that I'm missing.
Thank you very much!

You can do as follows:
main.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<include android:id="#+id/item_base_lang" layout="#layout/dictionary_list_item" />
<include android:id="#+id/item_learn_lang" layout="#layout/dictionary_list_item" />
</LinearLayout>
dictionary_list_item.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="wrap_content" >
<TextView
android:id="#+id/dictionary_list_item_text_header"
android:layout_width="fill_parent"
android:layout_height="wrap_content" />
<TextView
android:id="#+id/dictionary_list_item_text_content"
android:layout_width="fill_parent"
android:layout_height="wrap_content" />
</LinearLayout>
To set the text programmatically:
((TextView)findViewById(R.id.item_base_lang).findViewById(R.id.dictionary_list_item_text_header)).setText("item_base_lang_header");
((TextView)findViewById(R.id.item_base_lang).findViewById(R.id.dictionary_list_item_text_content)).setText("item_base_lang_content");
((TextView)findViewById(R.id.item_learn_lang).findViewById(R.id.dictionary_list_item_text_header)).setText("item_learn_lang_header");
((TextView)findViewById(R.id.item_learn_lang).findViewById(R.id.dictionary_list_item_text_content)).setText("item_learn_lang_content");
This Android wiki page shows how to use reusable UI components with XML layouts, but it doesn't show how to access nested reusable components from code.
Although it is fairly straightforward, it might be not so clear for those who are pretty new to Android Views.

The following two lines should help you get the languageHeader of both includes. You can do the same for languageText
findViewByid(R.id.activityBaseLangView).findViewById(R.id.languageHeader)
findViewByid(R.id.activityLearnLangView).findViewById(R.id.languageHeader)

Referencing a View in another XML file

I have a ListView in a file called a.xml.
<ListView
android:id="#+id/mylistview"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_weight="1"
android:scrollbars="none"
android:layout_above="XYZ"
/>
In a.xml, I also include another file called b.xml.
<include android:id="#+id/bottombar" layout="#layout/b" />
For one of the settings of the ListView, I want to reference an id (XYZ) that exists in b.xml.
Is there a way I can do this?
I've tried the following:
<RelativeLayout
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<include android:id="#+id/bottombar" layout="#layout/b" />
<ListView
android:id="#+id/mylistview"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_weight="1"
android:scrollbars="none"
android:layout_above="#id/bottombar_background"
/>
</RelativeLayout>
Where #id/bottombar_background exists in #layout/b, but Eclipse throws "no resource" errors at me.

After you have used setContentView(R.layout.a) you should be able to use findViewById(R.id.my_id_in_b).

Use this syntax: android:layout_toLeftOf="#+id/my_id_from_b". It prevents any reference issues.
The plus in this instance tells the compiler to do a second pass on the layout, looking for that id on the second time through. Try it out - I know it works, as I use this syntax all the time.