Develop Reference

Concatenating layouts during runtime

I am thinking to create a layout whose height is much more than the screen height. OK say, the parent layout is LinearLayout and it is set to provide a vertical scrollbar automatically.
Inside the parent layout, there are many controls (listview, gridview, listboxes, editboxes etc). To make it easier for design, can I put listview in one xml, gridview in one xml, listbox in one, editbox in one etc and then later use some defined function to concatenate and allocate them all in the parent layout ?
If this is not possible, how can I design a layout that has many controls allocated that design screen can't fit at design time ?

xml_common.xml
code:
<?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="#dimen/common_topheader_width"
android:background="#drawable/topheaderfor9patch" >
<ImageView
android:id="#+id/xml_common_header_imageLogotop"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_centerVertical="true"
android:layout_marginLeft="2dp"
android:layout_marginRight="#dimen/common_left_right_margin"
android:src="#drawable/qarrow" />
</RelativeLayout>
///////////////////////////////////////////
Main_view.xml
Code:
<?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:background="#drawable/mainbg"
android:orientation="vertical" >
<include layout="#layout/xml_common" />
</LinearLayout>
you can set different images as per your choice set in runtime of common view.

Android Resources doesn't display at runtime

I have few images that i want to use for the help. Where each image will be used in one activity. i have the images in drawable directory and referencing them using aliases for the different configurations. the images are extension is png.
in the UI designer the image is displayed, but not in run-time. it show white view
my Layout
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<View
android:id="#+id/help_img_screen"
android:layout_width="fill_parent"
android:layout_height="0dip"
android:layout_weight="1"
android:background="#drawable/todays_reminders_help"
android:contentDescription="#string/content_description" />
<CheckBox
android:id="#+id/help_chx_dont_show"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:gravity="center"
android:text="#string/dont_show_help" />
</LinearLayout>
my drawable todays_reminders_help.xml
<?xml version="1.0" encoding="utf-8"?>
<bitmap xmlns:android="http://schemas.android.com/apk/res/android"
android:gravity="fill"
android:src="#drawable/todays_reminders_activity_help" >
</bitmap>
i am getting white view at run-time not the image i am referencing? this happen on my test device.
However, when i test on the emulator it worked with no issue

You can try couple of things:
1. In your todays_reminders_help.xml, try to set the android:layout_width and android:layout_height to match_parent
2. Just to make sure if things are working as expected, you can test by setting a non-zero height for View with id help_img_screen. i.e replace
<View
android:id="#+id/help_img_screen"
android:layout_height="0dip"
android:layout_weight="1"
..../>
with
<View
android:id="#+id/help_img_screen"
android:layout_height="100dp"
..../>
and see if that helps. If it works, then you need to figure out why layout_weight is not working - you might have to use hierarchy viewer tool to see why it's not working.
Lastly, i would recommend that you approach this problem in a different way -
Make the View an ImageView and in real time i.e in the Java code, you can set the image src or background dynamically based on the activity/context. You can completely avoid using another layout file todays_reminders_help.xml
Hope this helps.

I want to bring my relative layout in bottom

what changes shall I make to bring the relative layout in bottom?
<?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" >
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="86dp"
android:layout_alignParentBottom="true"
android:layout_weight="0.08"
android:gravity="bottom" >
</RelativeLayout>
</LinearLayout>

You need to change your parent Layout to be a RelativeLayout, since the attribute android:layout_alignParentBottom does nothing for LinearLayout children:
<?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" >
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="86dp"
android:layout_alignParentBottom="true" >
</RelativeLayout>
</RelativeLayout>

You can achieve that by using a FrameLayout instead of a LinearLayout since it stacks childs from top to bottom by default.
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="86dp"
android:layout_gravity="bottom" >
</RelativeLayout>
</FrameLayout>

use
<?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" >
<!-- replace this by any other layout or view. You might want something here, right? -->
<View android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_weight="1"/>
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="86dp">
</RelativeLayout>
</LinearLayout>

There are two issues here. The first being that
android:gravity
is wrong. This sets the gravity for the contents of this Views children. So for example used in a TextView it would place the text at the bottom if the TextView. What you want instead is
android:layout_gravity
this sets the Views gravity within its parent.
The second problem is that android:gravity="bottom" doesn't work as you would expect in a LinearLayout who's orientation is vertical. I'm not sure I can explain why well so I will try to find a link in a bit that explains it. But if you change the orientation of the LinearLayout to horizontal you will see this.
So your best options are to change the orientation if that's a possibility and if not then change the root ViewGroup to a RelativeLayout and use the property android:alignParentBottom="true" as someone already suggested.
Edit for explanation
This blog post and this SO answer, among others explain it a little. But basically, if the orientation is horizontal then the Views are layed out from left to right as we expect so you can't control the left and right gravity. With a vertical orientation, the same is true for top and bottom gravity because where they are placed vertically is already determined by Android when you set that orientation. I hope this makes sense.

Android ScrollView Doesn't wrap to its child?

I have a problem with my ScrollView. It has an ImageView inside it. The imageView holds an image which is 480 * 3000 px. So It needs to be in a ScrollView so the user will have the ability to scroll down.
The problem is: when I test the application, the ScrollView does not wrap to the image hight. There is a black space under the image which is strange for me.
This is my XML code. I look forward for your opinion
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<ScrollView
android:id="#+id/scroll_view"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:scrollbars="vertical" >
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/image"
android:src="#drawable/image01"
android:scaleType="fitStart" />
</ScrollView>
</RelativeLayout>
Update:
This is how my image looks like with #ruhalde code. I can't take a screenshoot since it is big and you'll not see the whole picture so I draw it.

Rewrite your layout. Make the ScrollView the outer most element. Take a look at this good tutorial for more information: http://mobiforge.com/designing/story/understanding-user-interface-android-part-1-layouts

Use a LinearLayout instead of RelativeLayout which is deprecated by now. Set fillViewPort=true in your ScrollView XML or programatically if you want with setFillViewPort(true).
Put imageview inside a LinearLayout and that inside ScrollView, your XML should look like this:
LinearLayout
---ScrollView
----LinearLayout
------ImageView
Check out my XML here working good with a 800 x 4000 pixels image, perfectly scrolling vertical:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="fill_parent"
android:layout_height="fill_parent">
<ScrollView android:id="#+id/scrollView1"
android:layout_width="fill_parent" android:layout_height="wrap_content">
<LinearLayout android:id="#+id/linearLayout1"
android:layout_width="fill_parent" android:layout_height="fill_parent">
<ImageView android:id="#+id/mapa" android:layout_height="wrap_content"
android:layout_width="wrap_content"></ImageView>
</LinearLayout>
</ScrollView>
</LinearLayout>

To those who might be interested:
My problem was with the image I'm using, not how I organize my layouts. Thanks.

I believe you should use scrollView tag before your layout tag

How to draw 2 PNG Images to the screen at the same time

I'd like to know how to draw two PNG pictures onto the screen.
My XML layout: (named paperxml.xml)
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/layoutid"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<ImageView xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/paperid"
android:src="#drawable/paperrepresentation"
/>
<ImageView xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/rockid"
android:src="#drawable/rockrepresentation"
android:layout_alignTop="#id/paperid"
/>
</RelativeLayout>
What would be the java code to instantiate the XML layout and display both ImageViews on the screen at the same time?
Simply calling setContentView(R.drawable.paperxml); crashes my application on startup.

Replace the xml with:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/layoutid"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<ImageView android:id="#+id/paperid"
android:src="#drawable/paperrepresentation"
android:layout_width="wrap_content"
android:layout_height="wrap_content"/>
<ImageView android:id="#+id/rockid"
android:src="#drawable/rockrepresentation"
android:layout_width="wrap_content"
android:layout_height="wrap_content"/>
</LinearLayout>
Explanation:
RelativeLayout doesn't use android:orientation="vertical".
Every view should have android:layout_width and android:layout_height.
Add the xmlns:android thing just in the first element.

Calling setContentView(R.drawable.paperxml); is not crashing your code - it's your XML file. Macarse has the correct answer to your problem, and keep your code the same!
You may also want to look at the View Tutorials for some examples of setting up your XML and using different View objects.

I put the XML in but it only displays one ImageView Here's a screenshot of the emulator I took. i852.photobucket.com/albums/ab87/thomasjakway1/Capture.png Its worth mentioning that the file shown is paperrepresentation
If you look hard enough you will see that at the bottom there is a second very tiny image. You just need to increase the scale.