Develop Reference

I can't add another row of buttons

I want my fragment look like it has 3 buttons that fill the screen in both vertically and horizontally on the phone. I managed to do that somehow but I can't add another row of buttons. This is my layout... what am I doing wrong?
<?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">
<ScrollView
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
>
<Button
android:id="#+id/button1"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_weight="1" />
<Button
android:id="#+id/button2"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_weight="1" />
<Button
android:id="#+id/button3"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_weight="1" />
</LinearLayout>
</ScrollView>
</LinearLayout>

Scroll view contains only one direct child so you can not add second child directly you have to do following
<?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">
<ScrollView
android:layout_width="match_parent"
android:layout_height="0dp"
android:fillViewport="true"
android:layout_weight="1">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
>
<Button
android:id="#+id/button1"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_weight="1" />
<Button
android:id="#+id/button2"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_weight="1" />
<Button
android:id="#+id/button3"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_weight="1" />
</LinearLayout>
<!--add here second row and other continue same -->
</LinearLayout>
</ScrollView>
</LinearLayout>
NOTE: If scrollview is only one element you going to use then you can make it root layout by removing current linearlayout from root and also remove scrollview weight for same case, it is good practice to minimize the layout hierarchy to performance improvement

First Note : scroll view remove effect of weight property
Delete the scroll view element from your layout
Second note : each button make
<Button ...
android:layout_width="match_parent" android:layout_height="0dp" android:layout_weight="1" />
Because 0dp let the Android system calculate the height of button Equally

Android Java ViewStub for Empty Listview Adapter

I am trying to get the empty.xml layout display when the adapter listview is empty.
I tried with http://cyrilmottier.com/2011/06/20/listview-tips-tricks-1-handle-emptiness/
But I can't do it.
empty.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context=".Principal"
>
<ListView
android:id="#+id/listview_items"
tools:listitem="#layout/item_list"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:dividerHeight="1px"
android:divider="#ebebeb"
android:scrollbarStyle="insideOverlay"
>
</ListView>
<ViewStub
android:id="#+id/stub_import"
android:layout="#layout/empty"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_gravity="bottom" />
</LinearLayout>
main.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context=".Principal"
>
<ListView
android:id="#+id/listview_items"
tools:listitem="#layout/item_list"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:dividerHeight="1px"
android:divider="#ebebeb"
android:scrollbarStyle="insideOverlay"
>
</ListView>
<ViewStub
android:id="#+id/stub_import"
android:layout="#layout/empty"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_gravity="bottom" />
</LinearLayout>
I know the command to inflate and deflate is something.
((ViewStub) findViewById(R.id.stub_import)).setVisibility(View.VISIBLE);
// or
View importPanel = ((ViewStub) findViewById(R.id.stub_import)).inflate();
Where should I put the command to inflate when my listview is empty?
Thanks in advance.

Personally i do these in either of onCreate or onResume, by first checking if my listview is empty using the listview's adapter.getCount() method to check if the adapter is empty , then i inflate the viewStub.
My code looks like this :
if(adapter.getCount()==0){
ViewStub stub=(ViewStub) viewRoot.findViewById(R.id.viewstub);
stub.inflate();
}
My XML file looks Like
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.younickacademy.younickmobile.Fragment_AlertsList"
android:orientation="vertical">
<FrameLayout
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1">
<ListView
android:id="#+id/listview_alerts"
android:layout_width="fill_parent"
android:layout_height="fill_parent"></ListView>
<ViewStub
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:layout="#layout/empty_alert_list"
android:id="#+id/viewstub"/>
</FrameLayout>
<Button
android:layout_width="60dp"
android:layout_height="60dp"
android:layout_gravity="bottom|right"
android:layout_margin="10dp"
android:id="#+id/btn_new_alert"
android:elevation="6dp"
android:gravity="center"
android:text="+"
android:textColor="#color/textColorPrimary"
android:background="#drawable/circular_button_selector"/>
</LinearLayout>
And My empty_alert_list.xml layout looks like :
<?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">
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:text="No Emergency Alerts have been received Yet."
android:textStyle="bold"
android:gravity="center_horizontal"
/>
</RelativeLayout>
However this may not be the best implementation, but does solve my problem momentarily until a better hack is found.

Put ViewStub below listView

I'm programming for Android 2.2 (API level 8) and in my main View I have, in a simplified way, this:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/relativeParent"
android:layout_width="fill_parent"
android:layout_height="fill_parent" >
<TableRow
android:id="#+id/tableRow2"
android:layout_width="fill_parent"
android:layout_height="wrap_content" >
...
</TableRow>
<ListView
android:id="#+id/listview"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
</ListView>
<ViewStub
android:id="#+id/includeIdForPlayerStub"
android:layout_alignParentBottom="true"
android:layout_alignBottom="#+id/listview"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:inflatedId="#+id/playerStubId"
android:layout="#layout/player_stub" />
</RelativeLayout>
I want to put the ViewStub in the bottom of the parent, right below the listview, but as it is now it doesn't work. The LinearLayout added by ViewStub sits in the bottom of the screen, but the list goes below the added content, causing content of the list to be below and not visible/accessible. It's also evident looking at the scrollbar siting below the added content.
The rootview of the ViewStub is:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:gravity="bottom"
android:layout_gravity="center_horizontal|bottom"
android:background="#drawable/backrepeat"
android:baselineAligned="false" >
</LinearLayout>
Anyone knows how to solve this?
Thanks!

Change the ordering of your items so that your ViewStub is positioned first, then the ListView set to above your ViewStub:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/relativeParent"
android:layout_width="fill_parent"
android:layout_height="fill_parent" >
<TableRow
android:id="#+id/tableRow2"
android:layout_width="fill_parent"
android:layout_height="wrap_content" >
...
</TableRow>
<ViewStub
android:id="#+id/includeIdForPlayerStub"
android:layout_alignParentBottom="true"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:inflatedId="#+id/playerStubId"
android:layout="#layout/player_stub" />
<ListView
android:id="#+id/listview"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_above="#id/includeIdForPlayerStub"
android:layout_below="#id/tableRow2">
</ListView>
</RelativeLayout>

HorizontalScrollView inside a RelativeLayout: works fine on a 1.6+API, but not on 1.5 API

I am using a HorizontalScrollView inside a RelativeLayout. It works fine on a 1.6+API, but on 1.5 API the HorizontalScrollView does not scroll, what is the problem?
On 1.5 API (3) you can only see the first part of the HorizontalScrollView and there's no scrolling at all, while it seems to work fine on API4 and above.
To answer question, here's some code used:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:ads="http://schemas.android.com/apk/lib/com.google.ads"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<HorizontalScrollView
android:id="#+id/pscroll"
android:scrollbars="horizontal"
android:orientation="horizontal"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_below="#id/ad"
android:fillViewport="true"
android:scrollbarAlwaysDrawHorizontalTrack="true">
<LinearLayout android:orientation="horizontal" android:id="#+id/LinearLayout01" android:scrollbars="horizontal" android:layout_width="fill_parent" android:layout_height="wrap_content">
<ImageButton android:id="#+id/P1" android:layout_width="wrap_content" android:layout_height="wrap_content" />
<ImageButton android:id="#+id/P2" android:layout_width="wrap_content" android:layout_height="wrap_content"/>

Edit: refined, based off of negative feedback (apparently people expect their hand to be held through this)
A scroll view is meant to contain a layout, not the reversal of that. Therefore your layout should be:
<HorizontalScrollView android:id="#+id/pscroll"
android:scrollbars="horizontal" android:orientation="horizontal"
android:layout_width="fill_parent" android:layout_height="wrap_content"
android:layout_below="#id/ad" android:fillViewport="true"
android:scrollbarAlwaysDrawHorizontalTrack="true">
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:ads="http://schemas.android.com/apk/lib/com.google.ads"
android:layout_width="fill_parent" android:layout_height="fill_parent"
android:orientation="vertical">
<LinearLayout android:orientation="horizontal"
android:id="#+id/LinearLayout01" android:scrollbars="horizontal"
android:layout_width="fill_parent" android:layout_height="wrap_content">
<ImageButton android:id="#+id/P1" android:layout_width="wrap_content"
android:layout_height="wrap_content" />
<ImageButton android:id="#+id/P2" android:layout_width="wrap_content"
android:layout_height="wrap_content" />
</LinearLayout>
</RelativeLayout>
</HorizontalScrollView>

How to add an ActionBar above a TabWidget?

I am creating a custom bar above a TabHost. For some reason the custom bar does not appear above the TabHost, instead it is drawn behind it. Not sure why. Here is my XML:
<?xml version="1.0" encoding="utf-8"?>
<TabHost xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#android:id/tabhost"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<!--
<RelativeLayout android:layout_height="wrap_content" android:layout_width="match_parent" android:id="#+id/actionbarRelativeLayout">
<ImageButton android:layout_height="wrap_content" android:layout_width="wrap_content" android:src="#drawable/icon" android:id="#+id/stocktwitsImageButton"></ImageButton>
<ImageButton android:layout_height="wrap_content" android:layout_width="wrap_content" android:src="#drawable/icon" android:id="#+id/composeImageButton" android:layout_alignParentRight="true"></ImageButton>
</RelativeLayout>
-->
<LinearLayout
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:padding="5dp">
<TabWidget
android:id="#android:id/tabs"
android:layout_width="fill_parent"
android:layout_height="wrap_content" />
<FrameLayout
android:id="#android:id/tabcontent"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:padding="5dp" />
</LinearLayout>
</TabHost>

Do not use TabHost as the root of your layout. Put your TabHost inside a LinearLayout with orientation:vertical.
Then inside the LinearLayout and before the TabHost, you can put your ActionBar.