创新实践记录四
相册功能的实现
本来之前还想实现切换前后摄像头功能的，但ARcore有些功能只能用后置摄像头，于是作罢，来实现相册功能。 因为要调用安卓的SDK给Unity使用，需要AndroidStudio导出arr包。这一过程极其折磨，各种莫名其妙的错误。
一、AndroidStudio部分
1.1新建项目
首先创建一个Android空白工程，注意因为是要把编译出的arr包导入Unity工程，所以工程的包名要一致。 红框里是包名，要和Unity工程的一致。
1.2添加Unity的classes.jar引用
（1）把Unity引擎目录下的classes.jar文件拷贝至Android Studio工程中的libs目录 版本不同有所区别 Unity版本为5.0之前时，classes.jar的路径： unity的安装路径\Editor\Data\PlaybackEngines\androidplayer\bin下的classes.jar
Unity版本为5.0及其之后时，classes.jar的路径： unity的安装路径\Editor\Data\PlaybackEngines\AndroidPlayer\Variations\mono \Release\Classes （2）右击"Project"视图，打开"Open Module Settings", 添加“classes.jar”依赖 注意：红框选择的是Compile only, 而不是Implemetation,这样选择的原因是最后我们打包出来的aar文件将不会包含这个jar包，如果使用Implemetation 将会把这个jar放到最后打出来的aar包中，我们得手动删除掉，不然我们打Apk的时候会出错，因为unity会使用自己的这个jar包。
1.3修改build.gradle
1.将com.android.application 改为 com.android.library 2.将applicationId “com.qxlz.ARMuseum” 删除掉 然后修改完后编译Gradle
1.4修改AndroidManifest.xml文件
<?xml version
="1.0" encoding
="utf-8"?>
<manifest xmlns
:android
="http://schemas.android.com/apk/res/android"
package
="com.qxlz.ARMeseum">
<application
android
:icon
="@drawable/ic_launcher_background"
android
:label
="@string/app_name">
<meta
-data
android
:name
="com.google.android.actions"
android
:resource
="@xml/provider_paths" />
<activity android
:name
=".MainActivity">
<intent
-filter
>
<action android
:name
="android.intent.action.MAIN" />
<category android
:name
="android.intent.category.LAUNCHER" />
</intent
-filter
>
</activity
>
<!-- 连接互联网的权限
-->
</application
>
<uses
-permission android
:name
="android.permission.INTERNET" /> <!-- SDCard写入数据权限
-->
<uses
-permission android
:name
="android.permission.WRITE_EXTERNAL_STORAGE" />
</manifest
>
增加了xml文件
<?xml version
="1.0" encoding
="utf-8"?>
<paths xmlns
:android
="http://schemas.android.com/apk/res/android">
<external
-path name
="external_files" path
="."/>
</paths
>
1.5MainActivity.java
import android
.app
.Activity
;
import android
.content
.Intent
;
import android
.graphics
.Bitmap
;
import android
.graphics
.BitmapFactory
;
import android
.net
.Uri
;
import android
.os
.Build
;
import android
.os
.Bundle
;
import android
.os
.Environment
;
import android
.provider
.MediaStore
;
import android
.support
.v4
.content
.FileProvider
;
import android
.util
.Log
;
import com
.unity3d
.player
.UnityPlayer
;
import com
.unity3d
.player
.UnityPlayerActivity
;
import java
.io
.File
;
import java
.io
.FileNotFoundException
;
import java
.io
.FileOutputStream
;
import java
.io
.IOException
;
import
static android
.content
.Intent
.FLAG_GRANT_READ_URI_PERMISSION
;
import
static android
.content
.Intent
.FLAG_GRANT_WRITE_URI_PERMISSION
;
public class MainActivity extends UnityPlayerActivity
{
private static final
int TAKE_PHOTO
= 1;
private static final
int OPEN_GALLERY
= 2;
private static final
int CROP_PHOTO
= 3;
private Uri mPhotoUri
;
private Uri mCropPhotoUri
;
@
Override
protected void onCreate(Bundle savedInstanceState
)
{
super
.onCreate(savedInstanceState
);
}
public void TakePhoto(){
mPhotoUri
= GetUri(CreateFile("temp.png"));
Intent intent
= new Intent(MediaStore
.ACTION_IMAGE_CAPTURE
);
intent
.addFlags(Intent
.FLAG_GRANT_WRITE_URI_PERMISSION
);
intent
.addFlags(Intent
.FLAG_GRANT_READ_URI_PERMISSION
);
intent
.putExtra(MediaStore
.EXTRA_OUTPUT
, mPhotoUri
);
startActivityForResult(intent
, TAKE_PHOTO
);
}
public void OpenGallery()
{
Intent intent
= new Intent(Intent
.ACTION_PICK
,null);
intent
.setDataAndType(MediaStore
.Images
.Media
.EXTERNAL_CONTENT_URI
,"image/*");
startActivityForResult(intent
, OPEN_GALLERY
);
}
private Uri GetUri(File file
)
{
Uri uri
;
if(Build
.VERSION
.SDK_INT
>= 24)
{
uri
= FileProvider
.getUriForFile(this, getPackageName() + ".fileprovider", file
);
}
else
{
uri
= Uri
.fromFile(file
);
}
return uri
;
}
private File CreateFile(String name
)
{
File file
= new File(Environment
.getExternalStorageDirectory(), name
);
try
{
if(file
.exists())
{
file
.delete();
}
file
.createNewFile();
}catch(IOException e
)
{
e
.printStackTrace();
}
return file
;
}
private void StartCrop(Uri inputUri
)
{
mCropPhotoUri
= Uri
.fromFile(CreateFile("tempCrop.png"));
Intent intent
= new Intent("com.android.camera.action.CROP");
intent
.addFlags(FLAG_GRANT_READ_URI_PERMISSION
);
intent
.addFlags(FLAG_GRANT_WRITE_URI_PERMISSION
);
intent
.setDataAndType(inputUri
, "image/*");
intent
.putExtra("crop", "true");
intent
.putExtra("aspectX", 1);
intent
.putExtra("aspectY", 1);
// outputX outputY 是裁剪图片宽高
intent
.putExtra("outputX", 300);
intent
.putExtra("outputY", 300);
intent
.putExtra("scale", true);
intent
.putExtra("return-data", false);
intent
.putExtra("noFaceDetection", true);
intent
.putExtra(MediaStore
.EXTRA_OUTPUT
, mCropPhotoUri
);
startActivityForResult(intent
, CROP_PHOTO
);
}
protected void onActivityResult(int requestCode
, int resultCode
, Intent data
)
{
if(resultCode
== Activity
.RESULT_CANCELED
)
{
Log
.d("unity","user cancel operator!!");
return;
}
switch (requestCode
)
{
case TAKE_PHOTO
:
{
StartCrop(mPhotoUri
);
}
break;
case OPEN_GALLERY
:
{
Uri uri
= data
.getData();
StartCrop(uri
);
}
break;
case CROP_PHOTO
:
{
try
{
Bitmap bitmap
= BitmapFactory
.decodeStream(getContentResolver().openInputStream(mCropPhotoUri
));
FileOutputStream fOut
= null;
try
{
String path
= "/mnt/sdcard/Android/data/com.qxlz.ATRMuseum/files";
File destDir
= new File(path
);
if(!destDir
.exists())
{
destDir
.mkdirs();
}
fOut
= new FileOutputStream(path
+ "/" + "image.png");
}
catch (FileNotFoundException e
)
{
e
.printStackTrace();
}
if(bitmap
!= null)
{
bitmap
.compress(Bitmap
.CompressFormat
.PNG
, 100, fOut
);
try {
fOut
.flush();
} catch (IOException e
) {
e
.printStackTrace();
}
try {
fOut
.close();
} catch (IOException e
) {
e
.printStackTrace();
}
UnityPlayer
.UnitySendMessage("UnityPlugin","OnGetPhoto", "image.png");
}
}
catch(FileNotFoundException e
)
{
e
.printStackTrace();
}
}
break;
}
}
}
1.6修改activity_main.xml
1.7导出*.arr文件
点击“Build -> Build APK”，生成aar文件
二、Unity调用插件
拷贝*.aar文件跟AndroidMainfest.xml到Unity的Assets -> Plugins -> Android目录下 之后就可以写unity脚本了
using System
;
using System
.Collections
;
using System
.Collections
.Generic
;
using UnityEngine
;
using UnityEngine
.UI
;
public class TestPlugin : MonoBehaviour
{
public Button mBtnCamera
;
public Button mBtnGallery
;
public RawImage mImage
;
public Text mText
;
private Action
<byte[]> mPhotoAction
;
void Start()
{
mBtnCamera
.onClick
.AddListener(() =>
{
TakePhoto((datas
) =>
{
});
});
mBtnGallery
.onClick
.AddListener(() =>
{
OpenGallery((datas
) =>
{
});
});
}
public void TakePhoto(Action
<byte[]> callback
)
{
AndroidJavaClass jc
= new AndroidJavaClass("com.unity3d.player.UnityPlayer");
AndroidJavaObject jo
= jc
.GetStatic<AndroidJavaObject>("currentActivity");
jo
.Call("TakePhoto");
mPhotoAction
= callback
;
}
public void OpenGallery(Action
<byte[]> callback
)
{
AndroidJavaClass jc
= new AndroidJavaClass("com.unity3d.player.UnityPlayer");
AndroidJavaObject jo
= jc
.GetStatic<AndroidJavaObject>("currentActivity");
jo
.Call("OpenGallery");
mPhotoAction
= callback
;
GameObject quad
= GameObject
.CreatePrimitive(PrimitiveType
.Quad
);
quad
.transform
.position
= Camera
.main
.transform
.position
+ Camera
.main
.transform
.forward
* 2.5f;
quad
.transform
.forward
= Camera
.main
.transform
.forward
;
quad
.transform
.localScale
= new Vector3(1f, texture
.height
/ (float)texture
.width
, 1f);
Material material
= quad
.GetComponent<Renderer>().material
;
if (!material
.shader
.isSupported
)
material
.shader
= Shader
.Find("Legacy Shaders/Diffuse");
material
.mainTexture
= texture
;
Destroy(quad
, 5f);
Destroy(texture
, 5f);
}
void OnGetPhoto(string name
)
{
StartCoroutine(LoadPhoto(name
));
}
IEnumerator LoadPhoto(string name
)
{
mText
.text
= name
;
string path
= "file://" + Application
.persistentDataPath
+ "/" + name
;
WWW www
= new WWW(path
);
yield return www
;
mImage
.texture
= www
.texture
;
if (mPhotoAction
!= null)
{
mPhotoAction(((Texture2D
)mImage
.texture
).EncodeToPNG());
mPhotoAction
= null;
}
}
}
将脚本挂到场景的对象上，关联上图像和按钮，打包编译好后就实现相册和查看图片功能了
遇到的问题
（Error）—— Attribute application@icon value=(@mipmap/ic_launcher) from AndroidManifest.xml:7:9-43
百度了一下，这是一个编译的常见错误，主要是AS的Gradle插件默认会启用Manifest Merger Tool，若Library项目中也定义了与主项目相同的属性（例如默认生成的android:icon和android:theme），则此时会合并失败，并报上面的错误。 修改AndroidManifest.xml第2行的： xmlns:tools=“http://schemas.android.com/tools” 和application最后一行的 tools:replace=“android:icon, android:theme”
