Develop Reference

Overlay over an ImageView on Android

So I have a list of images that come from the web, I don't know which color are they and I want to place a text over the ImageView.
My idea is to place the ImageView, an image overlay with transparency gradient over that ImageView and the text above it. I want to mimic this behaviour:
Is there anyway to do this via XML?

When you write the XML for your list items which get inflated in the getView(...) of whatever ListAdapter you've written you can surely do this.
Something like this for the list item:
<?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">
<ImageView
android:layout_width="320dp"
android:layout_height="240dp"
android:background="#ACACAC"/>
<RelativeLayout
android:layout_width="320dp"
android:layout_height="240dp"
android:background="#drawable/gradient">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Here is your text"
android:textColor="#000000"
android:layout_alignParentBottom="true"/>
</RelativeLayout>
</RelativeLayout>
Then you create that drawable/gradient. For that you can recycle the answer from here.

Thanks to adityajones I managed to get there :)
So although this is my right answer, I'll mark his as the correct one!
<?xml version="1.0" encoding="utf-8"?>
<ImageView
android:layout_width="fill_parent"
android:layout_height="200dp"
android:scaleType="centerCrop"
android:src="#drawable/image" />
<RelativeLayout
android:layout_width="fill_parent"
android:layout_height="200dp"
android:background="#drawable/gradient_image" >
<TextView
android:id="#+id/text"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_alignParentLeft="true"
android:layout_margin="6dp"
android:layout_marginBottom="18dp"
android:shadowColor="#000"
android:shadowRadius="7.0"
android:text="This is some random text"
android:textColor="#color/white"
android:textSize="22sp" />
</RelativeLayout>

I'd use a FrameLayout or RelativeLayout. The first View you add to either should be the background ImageView, then obviously you'll need some TextViews and Other ImageViews [or Buttons, or ImageButtons, etc]
Seems like a reasonable layout: a background image, and then one additional view in each corner.
For the gradient, you'll probably want a separate Layout/View at the bottom with a gradient drawable as the background, although I can imagine you might be able to get away with setting the background of one of your TextViews as the gradient.

You do not have to use a gradient drawable file or set it in your xml..
you can do this pragmatically using GradientDrawable Class as explained in this related Question (Create a radial gradient programmatically) then set it as a background for a layout that covers your ImageView, this gives you ability to use different colors and orientations

Change background color dynamically and use a border

I have the following template
<?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="wrap_content"
android:orientation="vertical"
android:background="#drawable/borders" >
<RelativeLayout
android:id="#+id/layout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="5dp">
<ImageView
android:id="#+id/category_starred_icon"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/rating_not_important"
android:contentDescription="#string/app_name" />
<TextView
android:id="#+id/category_name"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_toRightOf="#id/category_starred_icon"
android:textIsSelectable="false"
android:textSize="18sp"
android:paddingLeft="5dp"
android:paddingTop="5dp"
android:paddingRight="5dp"
android:textColor="#android:color/white"
android:hint="#string/category" />
</RelativeLayout>
</LinearLayout>
i get a warning This RelativeLayout layout or its LinearLayout parent is possibly useless; transfer the background
attribute to the other view, i want solve it, but i have the follow problem i have a border in the LinearLayout is like a drop shadow but when i change the background color in my code
mLayout.setBackgroundColor(Color.paseColor(mColorString));
i lost the border, how i can solve the warning witout lose the border, the main problem is the background colors are dynamically

Have a look at this: http://developer.android.com/guide/topics/resources/drawable-resource.html#LayerList
This is an drawable that organizes other drawables in a layer list (one on top of the other). With it, you can use other drawables, like shape, to define the borders and the background the way you want.
I can't make a complete answer now, but if you search for this, I'm sure you can do it. When I have more time, I may come back to help you, if you haven't found out how to solve this yet.

Android 9-patch and drawable-mdpi

I created a simple 9-patch image for Android. Poured into a folder drawable-mpdi. Everything works, but the upper frame is lost. It is not clear why. See screenshot:
This is my 9-patch file:
https://dl.dropbox.com/u/30086473/input_login_active2.9.png
My XML layout:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="#color/white">
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:gravity="center_horizontal"
android:background="#drawable/login_bg"
android:orientation="vertical">
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/auth_logo"/>
<EditText
android:layout_width="273dip"
android:id="#+id/login"
android:layout_marginTop="20dip"
android:layout_height="wrap_content"
android:background="#drawable/auth_edit_text"
android:hint="#string/auth_login"/>
<EditText
android:layout_width="273dip"
android:id="#+id/password"
android:layout_height="wrap_content"
android:background="#drawable/auth_edit_text_left"
android:hint="#string/auth_login_left"
android:layout_marginLeft="17dip"/>
</LinearLayout>
</LinearLayout>
What is the problem? How to recycle 9-patch, that there was a blue frame at the upper of element?
There is #drawable/auth_edit_text:
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:drawable="#drawable/t" />
</selector>

Your pixel borders seem to be incorrect (reversed maybe). Try this instead:
With your original, you'd be stretching the phone icon as well, not just the bubble. Also, you had the content area and stretch area reversed for the top and bottom (I've inverted them in the attachment). While I don't know that that would specifically cause the problem you've shown, I would give it a try and see what happens.
EDIT: Try this:
EDITED ANSWER FROM COMMENTS: I think that may be your issue is that it's looking for the ldpi image, not finding one, and falling back to the default and scaling it down. Since the border is only 1 px, it simply disappears when scaled down.

Add a semi-opaque black layer over a background image in Android TextView

This is what I'm trying to do:
I have a .png image as background for my TextView; The color of the text is white. To make the text easier to read, I'd like add a seme-opaque, black layer on top of my .png image.
This is what I've done so far:
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/aboutContent"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical"
android:text="#string/aboutEN"
android:textColor="#FFFFFF"
android:background="#drawable/myimage"/>
I tried to add android:background="#color/blackOpaque">
But Eclipse complains that I've already got a background image. So I tried to change the transparency of my image file like this:
Drawable myimage = getResources().getDrawable(R.drawable.myimage);
myimage.setAlpha(50);
But nothing seems to happen at all.
What should I do? Thanks!
Thanks!

This saved my #$$!
<merge xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<ImageView android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:scaleType="center"
android:background="#drawable/myimage" />
<TextView android:id="#+id/aboutContent"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:text="#string/aboutEN"
android:background="#AA000000"
android:textColor="#ffffff" />

Gradient styles

In my Android application I've hidden the default title bar, introduced a TabView and added my own titlebar under that TabView's tabs. At the moment, I'm using the ?android:attr/windowTitleStyle style which makes my new titlebar look gray and gradient. It looks pretty good, but my screens are looking pretty grayscale. I'd like to spice things up a bit by making this titlebar a different color gradient.
What am I looking at here? Creating my own image and using it? The ?android:attr/windowTitleStyle style seems to expand depending on the height of your custom titlebar; so I'm not sure it's actually a single image.
I've attempted to throw a LinearLayout over it with a bit of translucency (ex: making the color #800000FF), but the gradient style I have behind this LinearLayout disappears.
Thanks for your help
Update:
Per my answer down below, I've figured out that I can create an XML file that defines a gradient and use that. It works fine inside a LinearLayout (titlebar_gradient) I have on my layout. However, it is not working on the outer-most LinearLayout (background_gradient). Could someone tell me why? As I understand it, the ListView should be transparent...
<?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"
android:background="#drawable/background_gradient"
>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="horizontal"
android:layout_width="fill_parent"
android:layout_height="47dip"
android:background="#drawable/titlebar_gradient"
android:gravity="center">
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="Item"
style="?android:attr/windowTitleStyle"
android:paddingLeft="5dip"
android:maxLines="1"
android:ellipsize="end" />
</LinearLayout>
<ListView
android:id="#+id/android:list"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:paddingTop="10dip"
android:clickable="false"
/>
<TextView
android:id="#+id/android:empty"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
/>
</LinearLayout>

I understand my problem now.
I've created an XML file in my drawables folder that looks like this
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle">
<gradient
android:startColor="#00CC66"
android:endColor="#009966"
android:angle="270"/>
/shape>
In my toolbar, I set the background to this drawable.