I'm working on a solutioning where managing multiple res folder to keep resource requirement separate and it worked great. To implement this I'm following well written document by Dmytro Danylyk.
In my case I have two different res folder with layout directory res/layout and res-home/layout.
**Now issue is: ** if I modified layout under res-home/layout it's not reflecting any changes even static text string update for TextView. It required clean and build every time.
Following code using to add resource availability from gradle file:
res.srcDirs +=
[
file("src/main/res_prefer/").listFiles(),
'src/main/res_prefer'
]
}
Any clue what I'm missing !!
I make a research, and I delve deep into Android resources files. According to this link, it says that Android externalize and separate users' resources from the code to allow using
these resources by Ids that will be generated in R.class, here is the text:
Once you externalize your application resources, you can access them using resource IDs that are generated in your project's R class.
(1): Does being the 'res' folder exists means generating the R.java class? In other words, is R.java a representation to "ids" assigned to any values inside 'res' folder?
(2): Is it possible to place my 'layout' or 'string' files in any other folders aside from 'res'?
Is R.java a representation to "ids" assigned to any values inside
'res' folder?
It is most likely the idea of R.java.
Is it possible to place my 'layout' or 'string' files in any other
folders aside from 'res'?
Yes you can do that but before you start make sure you checked the project structure view and not the other options like android structure view.
In your build.gradle
android {
....
sourceSets {
main {
res.srcDirs = [
"src/main/module-res/compose"
];
}
}
}
Then create the desired directory similar to what you have declared.
Here is an example image showing that it will work.
What's good about it is that you can make more res folder (just add it in the array and separate it with comma). Take note that each res folder must have its own drawable, layout etc. folder.
Example:
res.srcDirs = [
"src/main/module-res/compose",
"src/main/module-res/design",
"src/main/module-res/extra"
];
R.java file is an auto-generated file by aapt (Android Asset Packaging
Tool) that contains resource IDs for all the resources of res/
directory. when you create any component in the xml file, id for the
corresponding component is automatically created in this file.
when creating an layout file using android studio it will automatically put it under layout folder, but when you create it manually it will be classified as the parent folder, eg : create layout file under drawable will be called like R.drawable.mLayout, android studio will show it as warning but it will work fine, so yes you can put any type of xml under any folder and it will work fine, put it's easier to classify as default for more readability and clearer architecture
I'm working on a project with a lot of .xml layout files. I want to organize them in separate folders.
It seems like Resource Merging would be the right solution.
http://tools.android.com/tech-docs/new-build-system/resource-merging
I want to split my layout folder in activity, listview, dialog, button, etc.
How do I modify my project and build.gradle file to accomplish this ?
Resource merging isn't really the concept you're looking for here -- that document specifies how if you have multiple build types and flavors, how they combine to provide a single view of the project's resources that will be built into the final result. In your case, you probably have a single build type and flavor, and want to have subdirectories in your resources to help organize them better.
The bad news is that Android isn't very friendly about this. The build system expects resources to be arranged in a rigid format, with all layouts being in a single folder underneath your project root, for example, and it doesn't let you deviate from that. The best thing you can do is to have multiple resource folder trees, which would look like this:
AppModule
+ src
+ main
+ java
+ res
+ drawable
+ layout
+ ...etc...
+ extra-res
+ drawable
+ layout
+ ...etc...
Each resource sub-tree has its subdirectories in the same format. You don't need to have an exhaustive list of subdirectories in there if they're empty; just include the ones that have things you need.
To make this work, you need to have the following in your build.gradle script:
android {
sourceSets {
main {
res.srcDirs = ['src/main/res', 'src/main/extra-res']
}
}
}
I had developed 3 applications in android where the major functionalities are the same but the UI looks different. Images and the background color of the screens are different.
NOw, i want to create a single code base from which i can generate multiple .apk files for the 3 apps.
I tried creating 3 different packages for src folder for the 3 apps. But i dont know how to set the res folder for these apps.
Need pointers on creating a single code base from which we can generate multiple .apk files which includes only the respective src and res folders.
Use an Android Library Project that contains all your common code.
Create separate Android projects that reference the Library Project (you will need to copy your Manifest into each of these and make sure all components are declared with their full Java package name).
Put any resources specific to each app (drawables, colors etc) into the individual project resource folders and they will override similarly named resources in the library project at build time.
i think the best option is to use ant, you'll need to add an ant target for each build and change the resource folder.
if you use the generated build.xml, the res folder is defined like this
<property name="resource.absolute.dir" location="res" /> so you'll want to override that
Can't you put all of your common code into a library project and then just reference that project from each of the 3 unique projects that each contain the relevant resources.
Update: This answer is now obsolete when using the Gradle build system.
Why don't you use a single application, that does three different things based on SharedPreferences values set by the user, or from context at install time. If you really want to separate, you can have three different activities, and you decide which one to launch from a silent main Activity that redirects to either of the different ones.
An alternative is to have a unique activity that inflates itself dynamically from 3 different layouts at onCreate time.
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (...custom check for layout... equals(layout1)) {
setContentView(R.layout.main_layout1);
} else if (... equals(layout2)) {
setContentView(R.layout.main_layout2);
} else if (... equals(layout3)) {
setContentView(R.layout.main_layout3);
} else {
throw new IllegalStateException("Unknown layout!");
}
... your onCreate stuff....
}
It will make code maintenance easier (only one code source to modify, only one version-list and changeset to maintain)
Check here:
How to use SharedPreferences in Android to store, fetch and edit values
I would suggest using Gradle flavors.
It seems to explain all the basics really well. I just finished converting to Gradle today, and it works great. Custom app icons, names, and strings, etc.
As the website explains, part of the purpose behind this design was to make it more dynamic and more easily allow multiple APKs to be created with essentially the same code, which sounds similar what you're doing.
Also see a recent question I had, referring to your project structure and using custom code for each app.
In the Android SDK documentation, all of the examples used with the #drawable/my_image xml syntax directly address images that are stored in the res/drawable directory in my project.
I am wondering if it is explicitly not okay to create a sub directory within the drawable directory.
For example, if I had the following directory layout:
res/drawable
-- sandwiches
-- tunaOnRye.png
-- hamAndSwiss.png
-- drinks
-- coldOne.png
-- hotTea.png
Could I reference the image of a tuna salad sandwich as #drawable/sandwiches/tunaOnRye
Or do I have to keep the hierarchy flat in the drawable directory.
No, the resources mechanism doesn't support subfolders in the drawable directory, so yes - you need to keep that hierarchy flat.
The directory layout you showed would result in none of the images being available.
From my own experiments it seems that having a subfolder with any items in it, within the res/drawable folder, will cause the resource compiler to fail -- preventing the R.java file from being generated correctly.
The workaround I'm using (and the one Android itself seems to favor) is to essentially substitute an underscore for a forward slash, so your structure would look something like this:
sandwich_tunaOnRye.png
sandwich_hamAndSwiss.png
drink_coldOne.png
drink_hotTea.png
The approach requires you to be meticulous in your naming and doesn't make it much easier to wrangle the files themselves (if you decided that drinks and sandwiches should really all be "food", you'd have to do a mass rename rather than simply moving them to the directory); but your programming logic's complexity doesn't suffer too badly compared to the folder structure equivalent.
This situation sucks indeed. Android is a mixed bag of wonderful and terrible design decisions. We can only hope for the latter portion to get weeded out with all due haste :)
Actually, on Android Studio it is possible. You can have nested resources as shown here :
There is also a plugin to group resources here.
I recommend to avoid this though.
Yes - it does suck :) However you can use the assets folder and have sub directories in there and load images that way.
Use assets folder.
sample code:
InputStream is = null;
try {
is = this.getResources().getAssets().open("test/sample.png");
} catch (IOException e) {
;
}
image = BitmapFactory.decodeStream(is);
I've wrote an eclipse plugin which allows to create virtual subfolder by separating the file name with two underscores __. The project is in early stages, but don't worry it won't crash your IDE
more details can be found here, feel free to fork and send pull requests:
https://github.com/kirill578/Android-Sorted-Res-Folder
I like to use a simple script to flatten an organized directory structure provided by designers to something that can be used to generate an R file.
Run with current path in drawable-hdpi:
#! /bin/bash
DIRS=`find * -type d`
for dir in ${DIRS} ; do
for file in `ls ${dir}` ; do
mv ${dir}/${file} ${dir}_${file};
done
rmdir ${dir};
done
In android studio with gradle you can have multiple source directors which will allow you to separate resources. For example:
android {
....
android.sourceSets {
main.res.srcDirs = ['src/main/extraresdirnamed_sandwiches', 'src/main/res']
}
....
}
However the names must not collide which means you will still need to have names such as sandwiches_tunaOnRye but you will be able to have a seperate section for all of your sandwiches.
This allows you to store your resources in different structures (useful for auto generated content such as actionbargenerator)
One way to partially get around the problem is to use the API Level suffix.
I use res/layout-v1, res/layout-v2 etc to hold multiple sub projects in the same apk.
This mechanism can be used for all resource types.
Obviously, this can only be used if you are targeting API levels above the res/layout-v? you are using.
Also, watch out for the bug in Android 1.5 and 1.6.
See Andoroid documentation about the API Level suffix.
With the advent of library system, creating a library per big set of assets could be a solution.
It is still problematic as one must avoid using the same names within all the assets but using a prefix scheme per library should help with that.
It's not as simple as being able to create folders but that helps keeping things sane...
There is a workaround for this situation: you can create a resVector (for example) folder on the same level as default res folder. There you can add any drawable-xxx resource folders there:
resVector
-drawable
-layout
-color
After that all you need is to add
sourceSets {
main.res.srcDirs += 'src/main/resVector'
}
into your build.gradle file (inside android { }).
This is not perfect methods. You have to implement same way which is display here.
You can also call the image under the folder through the code you can use
Resources res = getResources();
Drawable shape = res. getDrawable(R.drawable.gradient_box);
TextView tv = (TextView)findViewByID(R.id.textview);
tv.setBackground(shape);
Not mine but I found this thread when looking for this issue, if your using Android Studio and Gradle Build system its pretty easy no plugins necessary just a little build file editing
https://stackoverflow.com/a/22426467/618419
Gradle with Android Studio could do it this way (link).
It's in the paragraph "Configuring the Structure"
sourceSets {
main {
java {
srcDir 'src/java'
}
resources {
srcDir 'src/resources'
}
}
}
create a folder in main.
like: 'res_notification_btn'
and create tree folder in. like 'drawable' or 'layout'
then in 'build.gradle' add this
sourceSets
{
main
{
res
{
srcDirs = ['src/main/res_notification_btn', 'src/main/res']
or
srcDir 'src/main/res_notification_btn'
}
}
}
#!/usr/bin/env ruby
# current dir should be drawable-hdpi/ etc
# nuke all symlinks
Dir.foreach('.') {|f|
File.delete(f) if File.symlink?(f)
}
# symlink all resources renaming with underscores
Dir.glob("**/*.png") {|f|
system "ln -s #{f} #{f.gsub('/', '_')}" if f.include?("/")
}
Check Bash Flatten Folder script that converts folder hierarchy to a single folder
assets/
You can use it to store raw asset files. Files that you save here are compiled into an .apk file as-is, and the original filename is preserved. You can navigate this directory in the same way as a typical file system using URIs and read files as a stream of bytes using the AssetManager. For example, this is a good location for textures and game data.
http://developer.android.com/tools/projects/index.html
Subdirectories are not allowed, the resource must contain only [a-z0-9_.].
No you have uppercase letters, and no forward slashes.
It is possible to have multiple drawable folders by having an extra folder parallel to 'res' with a subdirectory 'drawable' and then add following to gradle:
sourceSets {
main {
res.srcDirs 'src/main/<extra_res>'
}
}
Tested with gradle 6.5.1
For anyone using Xamarin (either Xamarin.Android or Xamarin.Forms), there is a way to do this.
In the .csproj file for the Android project find the line for MonoAndroidResourcePrefix (documented, though rather poorly, here). Add the subdirectories you are wanting to use here, separating each entry by semicolons. When building, Visual Studio strips these prefixes so that all of the resources end up in a flat hierarchy. You may need to reload the solution after making these changes.
These directories do not need to be subdirectories of the default Resources directory in the project.
Make sure that files you add are getting the build action set to "AndroidResource".
For Xamarin.Android, the visual editor won't recognize images and will show the error "This resource URL cannot be resolved" but the project will build and the image will be visible at runtime.
Right click on Drawable
Select New ---> Directory
Enter the directory name. Eg: logo.png(the location will already show the drawable folder by default)
Copy and paste the images directly into the drawable folder. While pasting you get an option to choose mdpi/xhdpi/xxhdpi etc for each of the images from a list. Select the appropriate option and enter the name of the image. Make sure to keep the same name as the directory name i.e logo.png
Do the same for the remaining images. All of them will be placed under the logo.png main folder.