[Solved]-How to use Gradle to generate Eclipse and Intellij project files for Android projects-eclipse

Maybe I'm missing something very obvious, but isn't the eclipse plugin what you're looking for? This generates a .project file as well as a .classpath file and updates these as needed when run subsequent times.

There is also an IDEA plugin, though I haven't used this one and can't speak to it.

Hope that helps.

As answered in Issue 57668 by Android team (raised by @arcone)

Project Member #2 x...@android.com

The eclipse plugin is not compatible with the android plugin.

You will not be able to import an Android gradle project into Eclipse using the default Gradle support in Eclipse.

To make it work in Eclipse we will have to change the Gradle plugin for Eclipse, the same way we are modifying the Gradle support in IntelliJ

That is Android team is working on gradle plugin for IntelliJ and gradle plugin for Eclipse needs to be updated too.

What is possible with Eclipse now is

.1. import the project as general project

.project

<?xml version="1.0" encoding="UTF-8"?>
<projectDescription>
    <name>OpenSpritz-Android</name>
    <comment></comment>
    <projects>
    </projects>
    <buildSpec>
    </buildSpec>
    <natures>
    </natures>
</projectDescription>

.2. Put 2 Eclipse . "dot" files into modules into /OpenSpritz-Android/app/src/main and /OpenSpritz-Android/lib/src/main

.project

<?xml version="1.0" encoding="UTF-8"?>
<projectDescription>
    <name>OpenSpritz-Android-app</name>
    <comment></comment>
    <projects>
    </projects>
    <buildSpec>
        <buildCommand>
            <name>com.android.ide.eclipse.adt.ResourceManagerBuilder</name>
            <arguments>
            </arguments>
        </buildCommand>
        <buildCommand>
            <name>com.android.ide.eclipse.adt.PreCompilerBuilder</name>
            <arguments>
            </arguments>
        </buildCommand>
        <buildCommand>
            <name>org.eclipse.jdt.core.javabuilder</name>
            <arguments>
            </arguments>
        </buildCommand>
        <buildCommand>
            <name>com.android.ide.eclipse.adt.ApkBuilder</name>
            <arguments>
            </arguments>
        </buildCommand>
    </buildSpec>
    <natures>
        <nature>com.android.ide.eclipse.adt.AndroidNature</nature>
        <nature>org.eclipse.jdt.core.javanature</nature>
    </natures>
</projectDescription>

.classpath

<?xml version="1.0" encoding="UTF-8"?>
<classpath>
    <classpathentry kind="src" path="java"/>
    <classpathentry kind="src" path="gen"/>
    <classpathentry kind="con" path="com.android.ide.eclipse.adt.ANDROID_FRAMEWORK"/>
    <classpathentry exported="true" kind="con" path="com.android.ide.eclipse.adt.LIBRARIES"/>
    <classpathentry exported="true" kind="con" path="com.android.ide.eclipse.adt.DEPENDENCIES"/>
    <classpathentry kind="output" path="bin/classes"/>
</classpath>

.3. Import as Existing Android Code into Workspace

you can then browse code in familiar way, but even after that you won't be able to run with Eclipse ADT.

.4.

Now you can run build and tasks with gradle CLI or Nodeclipse/Enide Gradle for Eclipse (marketplace)

discuss at https://github.com/Nodeclipse/nodeclipse-1/issues/148

The following worked for me

eclipse.classpath.plusConfigurations += configurations.compile

eclipse.classpath.file {
    beforeMerged { classpath ->
    classpath.entries.removeAll() { c -> 
        c.kind == 'src'
    }
}

withXml {
    def node = it.asNode()

    node.appendNode('classpathentry kind="src" path="src/main/java"')
    node.appendNode('classpathentry kind="src" path="src/debug/java"')
    node.appendNode('classpathentry kind="src" path="gen"')

    node.children().removeAll() { c ->
        def path = c.attribute('path')
        path != null && (
                path.contains('/com.android.support/support-v4')
                )
    }
  }
}

eclipse.project {
   name = 'AndroidGradleBasic'

   natures 'com.android.ide.eclipse.adt.AndroidNature'
   buildCommand 'com.android.ide.eclipse.adt.ResourceManagerBuilder'
   buildCommand 'com.android.ide.eclipse.adt.PreCompilerBuilder'
   buildCommand 'com.android.ide.eclipse.adt.ApkBuilder'
}

Source - http://blog.gouline.net/2013/11/02/new-build-system-for-android-with-eclipse/

Sample - https://github.com/krishnaraj/oneclipboard

I've created a new Gradle plugin that generates the appropriate Eclipse .project and .classpath files, based on the answer provided by Johannes Brodwall on this stack overflow.

See https://github.com/greensopinion/gradle-android-eclipse for details.

There are four issues with the combination of the Gradle plugins 'com.android.application' and 'eclipse': First, the configuration classpaths are not added to Eclipse's classpath, but this is easy to fix. Second, something must be done about the .AAR-dependencies. This was a bit trickier. Third, we need to include the generated sources for things like R.java. Finally, we need to include Android.jar itself.

I was able to hack together a gradle configuration that would generate proper .classpath files for Eclipse from an Android Studio build.config. The effects were very satisfying to my CPU fan, which had been running constantly with Android Studio. Eclipse sees the resulting project as a fully functional Java project, but only that.

I ended up putting the following directly in build.gradle in my app-project:

apply plugin: 'eclipse'
eclipse {
    pathVariables 'GRADLE_HOME': gradle.gradleUserHomeDir, "ANDROID_HOME": android.sdkDirectory 
    classpath {
        plusConfigurations += [ configurations.compile, configurations.testCompile ]

        file {
            beforeMerged { classpath ->
                classpath.entries.add(new org.gradle.plugins.ide.eclipse.model.SourceFolder("src/main/java", "bin"))
                // Hardcoded to use debug configuration
                classpath.entries.add(new org.gradle.plugins.ide.eclipse.model.SourceFolder("build/generated/source/r/debug", "bin"))
                classpath.entries.add(new org.gradle.plugins.ide.eclipse.model.SourceFolder("build/generated/source/buildConfig/debug", "bin"))
            }

            whenMerged { classpath ->
                def aars = []
                classpath.entries.each { dep ->
                    if (dep.path.toString().endsWith(".aar")) {
                        def explodedDir = new File(projectDir, "build/intermediates/exploded-aar/" + dep.moduleVersion.group + "/" + dep.moduleVersion.name + "/" + dep.moduleVersion.version + "/jars/")
                        if (explodedDir.exists()) {
                            explodedDir.eachFileRecurse(groovy.io.FileType.FILES) {
                                if (it.getName().endsWith("jar")) {
                                    def aarJar = new org.gradle.plugins.ide.eclipse.model.Library(fileReferenceFactory.fromFile(it))
                                    aarJar.sourcePath = dep.sourcePath
                                    aars.add(aarJar)
                                }
                            }
                        } else {
                            println "Warning: Missing " + explodedDir
                        }
                    }
                }
                classpath.entries.removeAll { it.path.endsWith(".aar") }
                classpath.entries.addAll(aars)

                def androidJar = new org.gradle.plugins.ide.eclipse.model.Variable(
                    fileReferenceFactory.fromPath("ANDROID_HOME/platforms/" + android.compileSdkVersion + "/android.jar"))
                androidJar.sourcePath = fileReferenceFactory.fromPath("ANDROID_HOME/sources/" + android.compileSdkVersion) 
                classpath.entries.add(androidJar)
            }
        }
    }
}

// We need build/generated/source/{r,buildConfig}/debug to be present before generating classpath
//  This also ensures that AARs are exploded 
eclipseClasspath.dependsOn "generateDebugSources"


// Bonus: start the app directly on the device with "gradle startDebug"
task startDebug(dependsOn: "installDebug") << {
    exec {
        executable = new File(android.sdkDirectory, 'platform-tools/adb')
        args = ['shell', 'am', 'start', '-n', android.defaultConfig.applicationId + '/.MainActivity']
    }
}

Run gradle eclipse and you will have an Eclipse-project that can be imported and compiled. However, this project acts as a normal Java-project. In order to build the apk, I have to drop back to gradle command line and execute gradle installDebug. gradle processDebugResources picks up changes in Android XML files and regenerates the files under build/generated/source. I use the "monitor" program with Android SDK to view the app logs. I have so far not found any way to debug without Android Studio.

The only features I miss from Android Studio are debugging (but who has time for bugs!) and editing resources visually.

Gradle itself is a generic build tool, it is not created specifically for Android.

All the functionality is enabled using plug-ins. Traditionally, build plug-ins don't generate project structure. That's the job of project specific tools. The Android plug-in for Gradle follows this.

The problem is that current android tool in SDK generates old type of project structure (ant builds). The new project structure can only be generated via Android Studio.

There is a concept of archetypes in tools like Maven, which allow using project templates. Gradle does not support that yet (requests have been made for this feature).

Refer to this thread: http://issues.gradle.org/browse/GRADLE-1289 , some users have provided scripts to generate structure.

Build Initialization feature is in progress: https://github.com/gradle/gradle/blob/master/design-docs/build-initialisation.md

Hopefully some one can write a script to do that, refer to this guide for new project structure: http://tools.android.com/tech-docs/new-build-system/user-guide

Update

There is now an official Android IDE: Android Studio . It is based on Intellij and the new build system is Gradle based.