I use very large resource files in my project (movies).
Whenever I change just one line in my code and debug on my device it seems to copy all files again.
Is there a kind of incremental build in ADT? SO it copies only the changed parts?
Related
The question
When you need to use resource files, such as images, in your Android project, typically you put them in the res directory (e.g. res/drawable), and the Android build process picks them up by default. But what if your resource files come from a directory outside of your Android project? How do you copy them into a folder like res/drawable during sync or build?
What I have tried
I have a feeling that the solution is to write Gradle code, but I'm not sure how to do it. I tried the following code in my app module build.gradle file:
task copyResources(type: Copy) {
from '../../../images'
into 'res/drawable'
}
But it did not copy anything as far as I can tell. This is probably just my ignorance of how to use Gradle, and I could use some help.
I realize I could manually copy from ../../../images to res/drawable, but let's say those files change often, and I want to get the current version automatically whenever I sync or maybe whenever I build. If this is possible, I would appreciate knowing how to do it. If it is not possible, I would like to know that as well.
See How to run copy task with android studio into assets folder
Can do with adding
preBuild.dependsOn copyResources
after task copyResources(){...}
in your build.gradle.
But, it's not a good way for copying resources.
Generally you don't want to do that. The reason is that it makes what would otherwise be a clean source control system confused by the copied files.
A better idea would be to build an Android library (AAR) housed in a separate project, then consume them by adding that AAR as a dependency to the parent project.
Why does the md5sum value of an apk change after every build?
Every time i build my Android application in the Eclipse IDE using the Android Tools -> Export Signed Application package, i get an apk file that gives a different md5sum value. If i have not changed any of the source code, shouldn't the apk files give the exact same md5sum? This happens even if i build it just seconds apart. What is going on?
The individual files should compile with the same CRC. An APK however is like a zip file containing all your files and those files are stored with a timestamp. The timestamp will be different for each compile and this is what changes your md5sum.
Generating of R file works fine for me. But is there a way to get Eclipse to generate just the R file on demand.
Editing a layout file and re-ordering nextFocus attributes crashes the app, unless you regenerate the R file. So I have to clean the project to generate the R file. But my project is very large, and it feels like a waste of time to rebuild the whole project, just for one file. Is there a way/trick to generate just the R.file?
Note:
Build Automatically is checked.
I am working on Library Project, which contains most of the code base for free and paid versions of the app.
Let me reiterate what I understand from your question. Your project is huge and minor changes to a layout result in crashing - owing to rebuilding the entire project. So, you want to know how to build only a part of the project - with the R file instead of rebuilding the entire huge project on minor changes, which crashes.
What you can do is, uncheck the "Build automatically option", make your changes and build manually once all the changes have been made, instead of building the project on every saved change.
I don't think you can generate only the R file since it needs to read all the res files and generate ids for all the resources, excluding none...I don't think that can be done in parts.
There is a way to generate the R.java file from your resources using the Android Asset Packaging Tool (aapt) as stated here (thanks to Pearl for the pointer)
just click on project->buildautomatically to tick
You can't build R.java as per your requirement like it will not build whole project and generate only R.java file.
But let me tell you one thing, R.java file contains resources identifiers. Those identifiers will be generated if and only if project is build. So, you have to build project to stop crashing your project.
You can still unchecked Build Automatically and manually build project by Project -> Build Project option.
I'm trying to learn android development and I am initially confused by the different project structures between Eclipse and Android Studio. This makes it difficult to follow tutorials designed for Eclipse. Could anyone let me know why these differences exist? Should they exist?
For instance, if I were to locate the R.java file in the two different IDEs, the paths would look like this:
Eclipse: app\gen\com.example.app\R.java
Android Studio: app\build\source\r\debug\com.example.app\R.java
Why are these paths different? Why is my R.java located in a debug folder in Android Studio? This lead to some errors early on, and if anyone has any insight into these differences I would appreciate them.
The mystery: Android Studio's Project Structure and Build System
I don't know if this is because of the Gradle Build System (I'd wager it is), but I'll tell you what I've understood so far.
Update 4: 2014/09/11 Added Cheat Sheet for BuildTypes, Flavors and Variants(I finally feel confident to write this :D)
Update 3: 2014/09/11 Updated the comparison workspaces and projects to be precise
Update 2: 2014/04/17 Added more detail to AS project structure
Update 1: 2013/07/29 Added IntelliJ Project Structure
The IntelliJ's Project structure (shown at the end) is for IntelliJ with the android plugin. The Android Studio, however, has a project structure divided like so:
Structure: Projects and Modules
module in Android Studio is like a project in Eclipse
project in Android Studio is like a workspace in Eclipse (to be precise, a workspace with interdependent projects)
From the documentation (Android Studio is based on Intellij IDEA) :
Whatever you do in IntelliJ IDEA, you do that in the context of a
project. A project is an organizational unit that represents a
complete software solution.
Your finished product may be decomposed into a series of discrete,
isolated modules, but it's a project definition that brings them
together and ties them into a greater whole.
For Android, it means one project per app, and one module per library and per test app.
There are multiple issues if you try to build multiple apps within the same project. It's possible, but if you try (like I did), you will see that almost everything is designed to work with a single app per project.
For example, there is an option to "rebuild the project", which makes no sense with multiple apps, many other project settings would be useless, and the built-in VCS system isn't great when you have multiple repositories.
Structure: Folder Structure
Top Level Folders
1. Main Project
This would be entire project context (Eclipse Land: Like your workspace but limited to what's relevant to your project). Ex: HelloWorldProject if the name of the application you gave was HelloWorld
2. .idea
This where project specific metadata is stored by Android Studio (AS). (Eclipse Land: project.properties file)
3. Project Module
This is the actual project. ex: HelloWorld if your application name you gave was HelloWorld
4. gradle
This is where the gradle build system's jar wrapper i.e. this jar is how AS communicates with gradle installed in Windows (the OS in my case).
5. External Libraries
This is not actually a folder but a place where Referenced Libraries (Eclipse Land: Referenced Libraries) are shown. Here's where the Targeted Platform is shown etc.
[Side note: This where many of us in Eclipse Land used to delete the referenced libraries and Fix Project Properties to fix reference errors, remember?]
Project Folder in Detail
This is number #3 in the above list. Has the following sub dirs
1. build
This has all the complete output of the make process i.e. classes.dex, compiled classes and resources, etc.
In the Android Studio GUI, only a few folders are shown. The important part is that your R.java is found here under build/source/<flavor>/r/<build type(optional)>/<package>/R.java
2. libs
This is the standard libs folder that you see in eclipse land too
3. src
Here, you only see the java and res folder which correspond to the src folder and res folder in Eclipse Land. This is much welcomed simplification IMHO.
Note on Modules:
Modules are like Eclipse Land projects. Here the idea is that you have one application project (Module #3 in the list above) and several library projects(as separate Modules under the global project folder (#1 in the above list)) which the application project depends on. How these library projects can be re-used in other applications, I still haven't found out.
[Side note: The whole re-organization has some benefits like simplifications in src folder, but so many complications. The complications are mainly due VERY VERY thin documentation on this new project layout.]
The New Build System
User Guide for the new Build System
Explanation of flavors and buildTypes, etc - What is the hullabaloo about?
CheatSheet for flavors and buildTypes
BuildType: debug and release are buildTypes available by default on all projects. They are for building/compiling the SAME CODE to generate different APKs. For example on release APKs you would want to run proguard(for obfuscation), sign it with your key (as against the debug key), run optimizations (maybe via proguard or other tools), use slightly different packageNames (we use com.company.product for release and com.company.product.debug for debug), etc. We also use a debug flag (BuildConfig.DEBUG) to turn off logging to logcat (since it makes the app slow) on release builds. This makes for a faster debug build during development but also an optimized release build to put on play store.
Product Flavor: There are no default flavors available (or to be precise, the default flavor is blank/nameless). Flavors could be free version or paid version where they have DIFFERENT CODE. They share the same Main Code but different versions(or no versions) of a few source code files or resources.
BuildVariant: A buildVariant is what a generated APK actually corresponds to. They are named like so (in order) Product Flavor + Build Type = Build Variant.
Example 1: if you have free and paid as two flavors. The build variants you would get are:
Free - debug
Free - release
Paid - debug
Paid - release
So that is 4 possible APK configurations. A few configurations may not make sense in a particular project, but they are available.
Example 2: (for new projects/ no flavors) You have 2 buildVariants or APKs available, since the default flavor is nameless/blank:
debug
release
Compare this with Intellij's Project Structure if that helps:
The .idea (1) folder contains a number of subfolders, mainly with internal IntelliJ IDEA information.
The src (2) folder contains the MyActivity.java (3) file source code that implements the functionality of your application. The file belongs to the com.example package.
The res (4) folder contains various visual resources.
The layout/main.xml file (5) defines the appearance of the application constituted of resources of various types.
The values folder (6) is intended for storing .xml files that describe resources of various types. Presently, the folder contains a strings.xml file with String resources definitions. As you will see from the Adding a Color section, the layout folder can also contain, for example, a descriptor of colors.
The drawable folder (7) contains images.
The gen (8) folder contains the R.java (9) file that links the visual resources and the Java source code. As you will see from the sections below, IntelliJ IDEA supports tight integration between static resources and R.java. As soon as any resources are added or removed, the corresponding classes and class fields in R.java are automatically generated or removed accordingly. The R.java file also belongs to the com.example package.
Android Studio: app\build\source\r\debug\com.example.app\R.java
Why are these paths different? Why is my R.java located in a debug folder in Android Studio? This lead to some errors early on, and if anyone has any insight into these differences I would appreciate them.
Simply put, Android Studio is configured to build a debug Build Type on your system.
Eclipse/ADT is designed to support a single build at a time (from what I can tell). One of the primary goals of the new build system (from the user guide):
Make it easy to create several variants of an application,
either for multi-apk distribution or for different flavors of an application
So where as Eclipse/ADT could generate one R.java file, Android Studio supports multiple. The generated R.java is located in the debug folder because by default the new build system supports debug and release build types off the bat. If you changed your build variant (button, lower left hand corner of AS) to release AS will generate R.java in the release directory.
This might not mean anything for simple projects, but the support of Build Variants means a drastic simplification of the build process for many developers, including the project I'm working on.
Our project supports 4 flavors with 2 build types (debug and release), to support a total of 8 different APK combinations. And each of those combinations have slightly different configurations, so this build system really worked out for us. My android studio is installed on a different machine, but if memory serves my correctly the R.java file exists in build/source/<flavor>/r/<build type>/package/R.java. When our CI server builds the APK files it uses each of these R.java files to generate separate packages.
Google Discontinue the support for the Android Developer Tools
(ADT) in Eclipse is ending, per our announcement. You should migrate
your app development projects to Android Studio as soon as possible.
For more information on transitioning to Android Studio, see Migrating
to Android Studio.
So best for Android development tool for Android Studio only for all future support of Android M ---
For android Studio 3.0.1 and selected all features:
Android O latest
Android Auto
Android things
Android wear
Android TV
C++ support
Kotlin support
The structure in version 3.0.1 does not look at all like all other answers.
Recent structure is as displayed in 2018, Android Studio 3.0.1 01/2018.
Newbie kinda found something resembling to usable in feature sub-folder:
Update your Android Studio 3.0.1 01_2018:
ToolTip:
I am trying to build my android project using ant in command line mode.
It works with eclipse and it used to work with ant until i installed the latest android sdk.
I run ant release -buildfile projectdir\build.xml. The compilation process is ok, and after aligning the apk, it fails at runtime with ClassDefNotFoundError acra.ACRA.
I have tried to remove any reference to acra from the project, but it will fail at runtime when trying to execute any code coming from a library jar.
My jars are in the libs folder at the root of the project. And I sort of understood this would cause ant to link them into the apk. But it doesn't.
When I used a previous version of the android sdk, I had a file named build.properties with an attribute referencing the jars folder external.libs.dir=libs. But now I can't make this to work any more, even if I use the new attributes names jar.libs.dir=libs and the new attributes file name ant.properties.
I read that ClassDefNotFoundError is caused because at compile time the librairies are found, but they are not linked into the apk, so they can't be found at runtime.
How can I link the external jars in the apk please ?
The compilation process is ok, and after aligning the apk, it fails at runtime with ClassDefNotFoundError acra.ACRA
There is no acra.ACRA class in ACRA, at least not in the current edition. It's org.acra.ACRA.
My jars are in the libs folder at the root of the project. And I sort of understood this would cause ant to link them into the apk. But it doesn't.
Yes, it does. Then ProGuard is removing them, unless you teach ProGuard not to.