Develop Reference

Android scrollindicators style / color android

android:scrollIndicators="top|bottom"
does provide scroll indicators, but they are barely visible at all.
Screenshot of barely visible Scrollindicators
What theme/style color are they using, or how can I assign a custom color?

You can customize the scroll bar by changing its width and setting a custom shape.
Add following tags in your scroll view
android:fadeScrollbars="false"
android:scrollbarStyle="insideInset" // set as required..
android:scrollbarTrackVertical="#drawable/vertical_scrollview_track"
android:scrollbarSize="20dp"// set as required width..
Create following drawable in your drawable folder
vertical_scrollview_track.xml
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android">
<solid android:color="#E2E0EB" />
<stroke
android:width="1dp"
android:color="#b3a9a9" />
<size android:width="15dp" />
<corners android:radius="15dp" />
</shape>
change colour as required.

<style>
<item name="android:colorForeground">#FFF</item>
</style>
As with SwitchCompat's track, a low opacity / high transparency version of colorForeground is used. Setting it to full white (or black on light backgrounds) makes the scrollindicators at least a bit more visible before someone finds the real solution.

How to set specific color for background when being clicked on borderless button?

Short question:
Suppose I use this style on a button:
<Button
style="#style/Widget.AppCompat.Button.Borderless.Colored" ...
(or without the "Colored" part).
How do I set the background of it to be a selector that has a different color when being pressed? The default one is quite a bold color on pre-Lollipop...
I want to have all of the style working as the default (including padding), except for the color of the selector.

I think the easiest would be to create a typical multi-state drawable and replicate Android's default button drawable properties for padding, etc...
From the Android SDK AppCompat theme:
<!-- Colored bordered ink button -->
<style name="Base.Widget.AppCompat.Button.Colored">
<item name="android:background">#drawable/abc_btn_colored_material</item>
<item name="android:textAppearance">#style/TextAppearance.AppCompat.Widget.Button.Inverse</item>
</style>
They use the drawable abc_btn_colored_material, whose source is like this: https://github.com/dandar3/android-support-v7-appcompat/blob/master/res/drawable/abc_btn_borderless_material.xml
You can see it's just a layer list with the following multi-state drawable:
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:state_focused="true" android:drawable="#drawable/abc_btn_default_mtrl_shape"/>
<item android:state_pressed="true" android:drawable="#drawable/abc_btn_default_mtrl_shape"/>
<item android:drawable="#android:color/transparent"/>
</selector>
https://github.com/dandar3/android-support-v7-appcompat/blob/master/res/drawable/abc_btn_default_mtrl_shape.xml
<inset xmlns:android="http://schemas.android.com/apk/res/android"
android:insetLeft="#dimen/abc_button_inset_horizontal_material"
android:insetTop="#dimen/abc_button_inset_vertical_material"
android:insetRight="#dimen/abc_button_inset_horizontal_material"
android:insetBottom="#dimen/abc_button_inset_vertical_material">
<shape android:shape="rectangle">
<corners android:radius="#dimen/abc_control_corner_material" />
<solid android:color="#android:color/white" />
<padding android:left="#dimen/abc_button_padding_horizontal_material"
android:top="#dimen/abc_button_padding_vertical_material"
android:right="#dimen/abc_button_padding_horizontal_material"
android:bottom="#dimen/abc_button_padding_vertical_material" />
</shape>
</inset>
So just make it yours :) Copy the drawable xml into your app and customize it.
I don't know if you will be able to access the #dimen/... from outside the SDK package, those values are defined in the SDK Values.xml, take a look at https://github.com/dandar3/android-support-v7-appcompat/blob/master/res/values/values.xml . If it's not possible, just create your own version of the dimens in your values.xml
If there's a cleaner solution any android guru can point out, I'll be glad to know!
Requested Update
Another trick is to apply a ColorFilter to the whole Button View. It's a very simple thing but not useful for all situations, as the color filter will blindly change the view as a whole (including Font color, borders, etc...). However, smartly selecting Alpha on the colors, could work for specific situations.
I'd suggest a LightningColorFilter. To apply a color filter to the Button, or to any view, you can do something like
myButton.getBackground().setColorFilter(new LightingColorFilter(Color.WHITE, Color.RED));
Check out what every color means here: http://developer.android.com/reference/android/graphics/LightingColorFilter.html

Material Design suggestions for edit button for each item

I wanted to add an edit button to each button in a list of items. Android action buttons should only be used once per view so those don't make sense. Is there any other way of doing it by following material guidelines? This button should be something that flies off and flies on depending on whether the overall edit button is pressed or not.

You should use flat buttons because buttons pop from backgrounds, easily grab attention, and guide the user’s eye. Here is a nice post about this
UPDATED:
To design a flat button effect you have to do the following
define your button and set background to a drawable which contains definitions for status pressed and status default
for status pressed write a drawable resource with solid color
for status default write a drawable with a item pointing to status pressed drawable as a background. And draw a lighter shape as another item with a android:bottom="2dp"
flat_button.xml
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:state_pressed="true" android:drawable="#drawable/rect_pressed"/>
<item android:drawable="#drawable/rect_normal"/>
</selector>
rect_normal.xml
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
<item android:drawable="#drawable/rect_pressed" />
<item android:bottom="#dimen/layer_padding">
<shape android:shape="rectangle">
<corners android:radius="#dimen/corner_radius" />
<solid android:color="#color/blue_normal" />
</shape>
</item>
</layer-list>
rect_pressed.xml
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle">
<corners android:radius="#dimen/corner_radius" />
<solid android:color="#color/blue_pressed" />
</shape>
if you need to read the full tutorial go here.

You should probably use flat or raised button (depending on how important your edit function is).

Creating a ProgressBar in Android with no background

I would like to create a ProgressBar with no background. I've been able to turn the background transparent, but there is still padding in the space where the background normally shows. Setting padding to 0 does not change this. Is it possible to achieve what I want without creating a custom drawable?

The issue is that the default 9Patch images used for ProgressBar have space around them. For example below is the standard holo_dark image used for the primary progress, secondary progress and background . As you can see, they each have areas of transparent space in their images.
progress_primary_holo_dark.9.png
progress_secondary_holo_dark.9.png
progress_bg_holo_dark.9.png
To achieve what you are after, you'll need to supply your own 9Patch images which do not have this extra space. Use setProgressDrawable() in your code or android:progressDrawable in xml, to set the Drawable for your ProgressBar.
You can combine all the necessary images in a single LayerList Drawable like the Android OS does. For example:
<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
<item android:id="#android:id/background"
android:drawable="#drawable/my_progress_bg" />
<item android:id="#android:id/secondaryProgress">
<scale android:scaleWidth="100%"
android:drawable="#drawable/my_progress_secondary" />
</item>
<item android:id="#android:id/progress">
<scale android:scaleWidth="100%"
android:drawable="#drawable/my_progress_primary" />
</item>
</layer-list>
You can find all the default graphic resources used by Android in the sdk/platforms/android-xx/data/res/ folder on the computer you're developing on.

Android ImageButton background color

I have an ImageButton with a background image that has some transparency. By default, the button gets a grey background where the transparency pixels are - due to the Holo.Light theme. I tried setting the background color of the button to transparent via the setBackgroundColor(Color.TRANSPARENT) method. That works just fine and does what I need except now my button no longer has the light blue color when focused/pressed and looks rather flat (no borders around it, so it looks like an image).
I googled and saw that you can assign selectors as explained here but that would mean that I have to specify an image per button state and I don't want to do that. I want to inherit the focuses/pressed colors from the theme but overwrite the normal button background (when not pressed/focused) to transparent instead of grey. How can I achieve that?? Please provide a working example as I have tried many different combinations with no success.
Edit
Thank you all for helping. I figured out how to make this work without having to recreate the same image with the focused and pressed states for each button!
Here is my solution:
My button is defined as:
<ImageButton
android:id="#+id/ImageButton05"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:background="#drawable/button" />
And my background XML file (titled button.xml) is defined as follows:
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:state_pressed="true">
<layer-list>
<item android:drawable="#drawable/btn_default_pressed_holo_light"></item>
<item android:drawable="#drawable/network_wifi"></item>
</layer-list>
</item>
<item android:state_focused="true">
<layer-list>
<item android:drawable="#drawable/btn_default_focused_holo_light"></item>
<item android:drawable="#drawable/network_wifi"></item>
</layer-list>
</item>
<item android:state_hovered="true">
<layer-list>
<item android:drawable="#drawable/btn_default_focused_holo_light"></item>
<item android:drawable="#drawable/network_wifi"></item>
</layer-list>
</item>
<item>
<layer-list>
<item android:drawable="#drawable/btn_default_normal_holo_light"></item>
<item android:drawable="#drawable/network_wifi"></item>
</layer-list>
</item>
</selector>

You can put something into an xml file, for example, custom_button.xml and then set background="#drawable/custom_button" in the button view.
Please refer to this link as there is an xml example: Standard Android Button with a different color
I used it in my code and it worked just the way I wanted.
Reference:
Standard Android Button with a different color
Edited:
If you would rather use
Maybe you should try to set a border.
For example (Reference: Android - border for button ):
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle">
<gradient android:startColor="#FFFFFF"
android:endColor="#00FF00"
android:angle="270" />
<corners android:radius="3dp" />
<stroke android:width="5px" android:color="#000000" />
</shape>
OR,
You could try to set the style/theme for the button. (But it would be in a separate file)
The style/theme contains the color attributes for various states of button such as focused / enabled / disabled/ etc.
For setting background color/image and having click highlight effect,
Here is an example (Reference: How to programmatically setting style attribute in a view)
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item
android:state_pressed="true"
android:drawable="#drawable/btn_pressed" />
<item
android:state_pressed="false"
android:drawable="#drawable/btn_normal" />
</selector>
You can then apply this selector to a Button by setting the property android:background="#drawable/my_button".

I want to inherit the focuses/pressed colors from the theme but overwrite the normal button background (when not pressed/focused) to transparent instead of grey. How can I achieve that??
AFAIK you can't because the focus/pressed colors are built in to the same image resources that contain the grey background.
If you want to keep the system focus/pressed but remove the background you'll have to grab a copy of the image resources (which can be found in your SDK at /sdkroot/platforms/[version]/data/res/drawable-hdpi replace [version] with whatever api level you are after. And if needbe replace hdpi with another density) and edit out the grey button from them with a photo editor. Then make a selector that references your modified images and set that as the background for your button.
EDIT:
Here are the default holo button images for focused and pressed

You can use ImageView instead of ImageButton to solve your problem. Please set the android:background property of the ImageView to the background color of the parent.

You can write this in your xml file:
android:background="#null"
It worked for me.

if u don't need the default gray background and u need your ImageButton seems like an icon without no backgrounds just use android:background attribute and set it to
#android:color/transparent**
<ImageButton
android:id="#+id/ImageButton05"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:background="#android:color/transparent"
android:background="#drawable/button" />
hope that help anybody