拍照,保存到图库中,然后在Android设备中选择Uri

时间:2019-06-04 09:12:56

标签: android kotlin android-camera android-gallery

我正在尝试启动相机拍照,然后将其保存到图库中并恢复Uri,以将其显示为图像视图。

有了这个,稍后我将其发送到FirebaseStorage。

(我简化了变量和方法的名称,以提高可读性)

此刻,我执行了单击操作,以检查所需的权限。

button.setOnClickListener {
            val permissions = arrayOf(
                Manifest.permission.CAMERA,
                Manifest.permission.WRITE_EXTERNAL_STORAGE,
                Manifest.permission.READ_EXTERNAL_STORAGE
            )

            Permissions.check(context!!, permissions, null, null, object : PermissionHandler() {
                override fun onGranted() {
                    dispatchTakePictureIntent()
                }
            })
        }


private fun dispatchTakePictureIntent() {
        Intent(MediaStore.ACTION_IMAGE_CAPTURE).also { takePictureIntent ->
            takePictureIntent.resolveActivity(context!!.packageManager)?.also {
                val photoFile: File? = try {
                    createImageFile()
                } catch (ex: IOException) {
                    // Error occurred while creating the File
                    Log.d("PictureIntent", "Error trying to get file")
                    null
                }
                photoFile?.also {
                    val photoURI: Uri = FileProvider.getUriForFile(
                        context!!,
                        "com.elias.myapplication.fileprovider",
                        it
                    )
                    takePictureIntent.putExtra(MediaStore.EXTRA_OUTPUT, photoURI)
                    activity!!.startActivityForResult(takePictureIntent, REQUEST_IMAGE_CAPTURE)
                }
            }
        }
    }

按照google的文档,在清单中,我像这样添加了FileProvider的声明:

<provider
    android:name="androidx.core.content.FileProvider"
    android:authorities="${applicationId}.fileprovider"
    android:exported="false"
    android:grantUriPermissions="true">
    <meta-data
         android:name="android.support.FILE_PROVIDER_PATHS"
         android:resource="@xml/file_paths"/>
</provider>

这是所有问题都来了...

在xml文件file_paths中,如果我将路径放置为例如:

<?xml version="1.0" encoding="utf-8"?>
<paths>
    <external-files-path
        name="my_images"
        path="/storage/emulated/0/Android/data/com.elias.myapplication/files/Pictures/" />
</paths>

我收到此错误:

Process: com.elias.myapplication, PID: 24093
    java.lang.NullPointerException: Attempt to invoke virtual method 'android.content.res.XmlResourceParser android.content.pm.ProviderInfo.loadXmlMetaData(android.content.pm.PackageManager, java.lang.String)' on a null object reference
        at androidx.core.content.FileProvider.parsePathStrategy(FileProvider.java:605)
        at androidx.core.content.FileProvider.getPathStrategy(FileProvider.java:579)
        at androidx.core.content.FileProvider.getUriForFile(FileProvider.java:417)
        at com.elias.myapplication.ui.main.MainFragment.dispatchTakePictureIntent(MainFragment.kt:76)
        at com.elias.myapplication.ui.main.MainFragment.access$dispatchTakePictureIntent(MainFragment.kt:28)
        at com.elias.myapplication.ui.main.MainFragment$onViewCreated$1$1.onGranted(MainFragment.kt:59)
        at com.nabinbhandari.android.permissions.Permissions.check(Permissions.java:105)
        at com.el.myapplication.ui.main.MainFragment$onViewCreated$1.onClick(MainFragment.kt:57)
        at android.view.View.performClick(View.java:7333)
        at android.widget.TextView.performClick(TextView.java:14160)
        at android.view.View.performClickInternal(View.java:7299)
        at android.view.View.access$3200(View.java:846)
        at android.view.View$PerformClick.run(View.java:27773)
        at android.os.Handler.handleCallback(Handler.java:873)
        at android.os.Handler.dispatchMessage(Handler.java:99)
        at android.os.Looper.loop(Looper.java:214)
        at android.app.ActivityThread.main(ActivityThread.java:6981)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1445)

在阅读有关SO的更多问题时,我找到了“解决方案”。使用以下命令修改xml文件:

<?xml version="1.0" encoding="utf-8"?>
<paths>
  <external-path
    name="external"
    path="." />
  <external-files-path
    name="external_files"
    path="." />
  <cache-path
    name="cache"
    path="." />
  <external-cache-path
    name="external_cache"
    path="." />
<files-path
    name="files"
    path="." />
</paths>

使用此解决方案不会崩溃,但是在onActivityResult中,意图到达null

这是我迷路的地方。

我该如何解决?

1 个答案:

答案 0 :(得分:0)

  

我收到此错误:

path相对于元素名称中定义的基本位置。使用:

<?xml version="1.0" encoding="utf-8"?>
<paths>
    <external-files-path
        name="my_images"
        path="Pictures" />
</paths>
  

但是,在onActivityResult中,意图到达null

应该为null。您知道图像应该在哪里:photoFile所标识的位置。在那寻找。有关将FileProviderACTION_IMAGE_CAPTURE一起使用的示例,请参见this sample app