I am writing an extremely simple Android application. In doing so, I've found it's quite difficult for me to emulate the button UI elements that are found on the Droid X application selector screen. For those not familiar, they are an icon with white text beneath them. The text has a black rounded rectangle behind it and when the button is clicked, the background beneath the icon and text turns red.
My current solution involves StateListDrawables, but then the rounded rectangle has a fixed width, and has to be edited into every button icon. Localization is an eventual goal, so my solution is temporary at best. I assume there's a less stupid way to do this?
I haven't tried this, and I've never seen the button you're talking about. But the process should be something similar.
First you create your drawables (the actual background images). One with the red background and one transparent. Your drawable XML would look something like this:
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:state_focused="true" android:state_pressed="true" android:drawable="#drawable/btn_bg_red"/>
<item android:state_focused="false" android:state_pressed="true" android:drawable="#drawable/btn_bg_red"/>
<item android:state_focused="true" android:drawable="#drawable/btn_bg_pressed"/>
<item android:state_focused="false" android:state_pressed="false" android:drawable="#android:color/transparent"/>
</selector>
Then your button itself can be declared similar to this:
<Button android:id="#+id/droid_x_btn"
android:layout_height="wrap_content"
android:layout_width="wrap_content"
android:text="Droid Does"
android:drawableTop="#drawable/btn_icon" <!-- this is for the icon on top -->
android:background="#drawable/ic_droid_x_button" <!-- The name of the above file without extension -->
android:textColor="#color/white" />
Hope this helps!
Related
So my graphics artist came to me with a really cool layout for controls on our new app. The problem is getting these images laid out since most views in android are rectangular. See image for what I have to work with.
Any idea how to layout these buttons so they shape around each other if that makes sense?
If the problem is the layout, you can draw the buttons and save it as png. You can layout your app by RelevantLayout . And use the "selector" to change the button image when user press an so on.
selector example: "drawable/selector1.xml"
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:state_focused="true" android:state_pressed="true" android:drawable="#drawable/buttonClicked" /> <!-- focused and pressed-->
<item android:state_pressed="true" android:drawable="#drawable/buttonClicked" /> <!-- pressed -->
<item android:drawable="#drawable/button" /> <!-- default -->
</selector>
use it like this:
android:background="#drawable/selector1"
the Views in android are rectangular, that is correct. The only workaround I see here: use multiple "invisible" Buttons (alpha set to 0). You can position them around the screen and assign the same action to some of them. Of course you'll need to implement the OnClickListener and use switch-case.
I want to have custom background for the menu items displayed in the ActionBar. I found out that I can do that by adding the following item to my app theme style definition:
<item name="android:actionBarItemBackground">#drawable/actionbar_button</item>
Where actionbar_button.xml contains:
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:drawable="#drawable/action_btn_on" android:state_pressed="true" />
<item android:drawable="#drawable/action_btn_off" />
</selector>
However, this causes the background image to also render behind the custom app logo displayed on the left of the ActionBar. After several attempts at figuring out a selector that would include only the buttons, I came up with this:
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:drawable="#drawable/action_btn_on" android:state_pressed="true" android:state_enabled="true" />
<item android:drawable="#drawable/action_btn_off" android:state_pressed="false" android:state_enabled="true"/>
<item android:drawable="#android:color/transparent"/>
</selector>
Which sort of worked, and after the app loads fully the background behind the logo is transparent as I want it. But the problem is that while it's still loading it briefly shows the logo with the button background behind it and more annoyingly, it scales and crops the logo to fit inside the fill area of the 9-patch graphic that is the button background. When finished loading, the background is switched out, but the scaling and cropping remains, which looks quite ugly. How can I fix it?
Have not found a working solution to the general problem of setting image-based backgrounds to ActionBar buttons, but the scaling/cropping does not happen if I use entered XML based backgrounds, such as created with a layer-list of shapes. For some cases in may not be viable, but in my case it was entirely possible, and maybe even better than using a bitmap based resource.
On Android application How can I get the glow effect on button when touched; I am looking for exact similar effect like ipod/iphone buttons
Use a StateListDrawable. Type this into a file and store it as res/drawable/button_bg.xml. Then create 4 images button_press.png, button_focus.png, button_disabled.png and button.png and last set your background to button_bg. If you want your button glow when touch you can add an image of your glowing button to state press. So when you press the system will get glowing_button.png and display it.
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:drawable="#drawable/button_press" android:state_pressed="true" />
<item android:drawable="#drawable/button_focus" android:state_focused="true" />
<item android:drawable="#drawable/button_disabled" android:state_enabled="false" />
<item android:drawable="#drawable/button" />
</selector>
The "magic" behind this is that android will go from the top to bottom and use the first one matching your buttons state.
In these links you can find some snippets to get exactly the same TabBar as iOS applications
iPhone Tab in Android
TabHost For Android
iTabs
I made a layout that is just simply a textview that says "What do you want?", followed by a series of buttons underneath it.
All of the buttons can be clicked/touched, but when I scroll with the trackball, none of them become highlighted. I noticed, however, then when I disable the background colors on the buttons, I can see the orange box that shows that button's focus.
Is there any way I can visibly see the focus while still being able to have a background color on the buttons?
EDIT: Found the solution! This helped A LOT. Standard Android Button with a different color
Create a "selector" resource in your res/drawable. It can look something like this:
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item
android:state_selected="false"
android:state_pressed="false"
android:drawable="#color/white" />
<item
android:state_pressed="true"
android:drawable="#color/orange" />
<item
android:state_selected="true"
android:state_pressed="false"
android:drawable="#color/blue" />
</selector>
Then set the background of your button to be:
android:background="#drawable/your_selector"
Rather than applying a simple background color to buttons, try applying a ColorStateList instead.
To do so, define a new XML file at
/res/color/buttonstate.xml
and use code such as the following:
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:color="# FOCUSED COLOR HERE"
android:state_focused="true" />
<item android:drawable="# DEFAULT COLOR HERE" />
</selector>
Notes:
You can definitely add more colors for more states, such as pressed, enabled, and certain other factors.
In the layout or code just reference R.color.buttonstate or #color/buttonstate (the XML's filename).
Make sure the default color is last. This is because it goes down the list and finds the first item that has all of the states the same as it. If you don't provide android:state_focused="false" for the default item and put it first, it will always display.
You can do a similar thing with drawables and
nine-patch drawables to make your own custom button styles.
Rather than just change the background color, consider using a 9-patch style. This is more work to begin, but you'll have much more control over your app's appearance.
Modify your Button layout to look something like this (the style line is the kicker):
<Button
style="#style/PushButton"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
Your styles.xml resource file then should contain a style similar to this:
<style name="PushButton">
<item name="android:background">#drawable/btn</item>
</style>
Then the btn.xml (put in in res/drawable) contents should look something like this:
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:drawable="#drawable/btn_pressed"
android:state_pressed="true" />
<item android:drawable="#drawable/btn_focused"
android:state_pressed="false"
android:state_focused="true" />
<item android:drawable="#drawable/btn_default"
android:state_focused="false"
android:state_pressed="false" />
You would then use some image editor to create files named btn_pressed.9.png, btn_focused.9.png, and btn_default.9.png. Drop these files in your res/drawable.
A good starting point is the Google IO app (I lifted the code examples from it). Just grab the png files and modify them to match your desired style.
Keep in mind you can put all sorts of stuff in the style now, like text size, height and width.
How can I have an imagebutton stay in the 'pressed' state when it is clicked? Basically I just want the background to be the depressed background, but I can't figure out how to set it. At the moment, I've just copied the selected button background into my res folder, but when I set it as the background, it becomes blurry (since the original image is bigger than the button itself).
Normal Background:
alt text http://img707.imageshack.us/img707/9199/ss20100426163452.png
What I'm getting:
alt text http://img707.imageshack.us/img707/912/ss20100426163357.png
alt text http://img3.imageshack.us/img3/8304/ss20100426163623.png
Also I don't believe I can actually use this method considering the many different UI layouts. The button should stay pressed as per the UI the user is using.
There are a few ways of doing this:
First, you can simply use an ImageButton, and manually toggle its image drawable on click in Java. This is what the stock Music player on Android does for the shuffle button, for example. Although you won't have control over the button background in its checked state, you'll be able to swap out the image, which may be favorable from an Android UI-consistency perspective.
Another option is to use a complex set of drawables and nine-patches to get an image inside a ToggleButton, with the option of changing the background and/or the image resource upon toggle. That's the option I'll show below. But remember, be cautious about UI consistency before doing this.
res/layout/foo.xml
...
<ToggleButton
android:textOn="" android:textOff=""
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#drawable/shuffle_button" />
...
res/drawable/shuffle_button.xml
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
<!-- use "#android:drawable/btn_default" to keep consistent with system -->
<item android:drawable="#drawable/toggle_button_background" />
<item android:drawable="#drawable/shuffle_button_image" />
</layer-list>
res/drawable/toggle_button_background.xml
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<!-- checked state -->
<item android:state_pressed="false" android:state_checked="true"
android:drawable="#drawable/btn_default_checked" />
<item android:state_window_focused="false" android:state_enabled="true"
android:drawable="#drawable/btn_default_normal" />
<item android:state_window_focused="false" android:state_enabled="false"
android:drawable="#drawable/btn_default_normal_disable" />
<item android:state_pressed="true"
android:drawable="#drawable/btn_default_pressed" />
<item android:state_focused="true" android:state_enabled="true"
android:drawable="#drawable/btn_default_selected" />
<item android:state_enabled="true"
android:drawable="#drawable/btn_default_normal" />
<item android:state_focused="true"
android:drawable="#drawable/btn_default_normal_disable_focused" />
<item android:drawable="#drawable/btn_default_normal_disable" />
</selector>
res/drawable/shuffle_button_image.xml
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:drawable="#drawable/ic_mp_shuffle_on_btn" android:state_checked="true" />
<item android:drawable="#drawable/ic_mp_shuffle_off_btn" />
</selector>
Image files
btn_default_<state>.9.png can be found in frameworks/base.git
under
core/res/res/drawable-hdpi
and
core/res/res/drawable-mdpi (also ldpi).
WARNING: if you use these, your app will look inconsistent on devices with customized OS UIs (i.e. HTC's Sense UI).
ic_mp_shuffle_<state>_btn.9.png need to be nine-patches, so that the image gets centered and not stretched to fit the button. Below are example hdpi versions of the icon:
res/drawable-(h|m|ldpi)/ic_mp_shuffle_(on|off)_btn.9.png
Final Note: Remember to be consistent with the system UI when possible, and be mindful of the fact that your app may run on devices with customized versions of the OS that have different graphics for UI elements like buttons. An example of this is HTC Sense, which has green buttons in place of the grey/orange/yellow ones in stock Android. So, if you end up copying the btn_default_... PNG files from the open source repository to create a toggle-able button background, you'll break consistency on those devices.