Android上传图片到Firebase Storage报No content provider问题及解决

问题复现代码 #

最初用于上传图片到Firebase Storage的代码如下：

override fun click(url: String?) {
        if (url != null) {
            Glide.with(requireContext()).load(url).into(binding.userAvatar)
            val uri = Uri.parse(url)
            val storageRef = storage.reference
            val avatarRef = auth.currentUser?.let { storageRef.child(it.uid).child("avatar.png") }
            val uploadTask: UploadTask = avatarRef!!.putFile(uri)
            uploadTask.addOnCompleteListener {
                if (it.isSuccessful) {
                    avatarRef.downloadUrl.addOnCompleteListener { url ->
                        user.userAvatar = url.toString()
                        Toast.makeText(context, "Upload image success!", Toast.LENGTH_SHORT).show()
                    }
                } else {
                    Toast.makeText(context, it.exception?.message, Toast.LENGTH_SHORT).show()
                    it.exception?.message?.let { it1 -> Log.e(TAG, it1) }
                }
            }
        }
    }

报错信息 #

运行后抛出如下异常：

发生未知错误，请检查HTTP返回码及服务端响应的内部异常。
     Code: -13000 HttpResult: 0
No content provider: /storage/emulated/0/Download/download.png
java.io.FileNotFoundException: No content provider: /storage/emulated/0/Download/download.png
        at android.content.ContentResolver.openTypedAssetFileDescriptor(ContentResolver.java:1673)
        at android.content.ContentResolver.openAssetFileDescriptor(ContentResolver.java:1503)
        at android.content.ContentResolver.openInputStream(ContentResolver.java:1187)
        at com.google.firebase.storage.UploadTask.<init>(UploadTask.java:137)
        at com.google.firebase.storage.StorageReference.putFile(StorageReference.java:241)
        at com.animals.snowy.profile.SetProfileFragment.click(SetProfileFragment.kt:87)
        at com.animals.snowy.util.GetImage.lambda$getOneImage$3$GetImage(GetImage.java:109)
        at com.animals.snowy.util.GetImage$$ExternalSyntheticLambda3.onClick(Unknown Source:6)
        at android.view.View.performClick(View.java:7125)
        at android.view.View.performClickInternal(View.java:7102)
        at android.view.View.access$3500(View.java:801)
        at android.view.View$PerformClick.run(View.java:27336)
        at android.os.Handler.handleCallback(Handler.java:883)
        at android.os.Handler.dispatchMessage(Handler.java:100)
        at android.os.Looper.loop(Looper.java:214)
        at android.app.ActivityThread.main(ActivityThread.java:7356)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:492)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:930)

问题原因 #

传入的参数url是本地文件的绝对路径字符串，直接调用Uri.parse()生成的Uri缺少file://协议标识，Firebase Storage的putFile方法会默认把无协议的Uri当作Content Uri尝试通过ContentResolver读取，本地文件路径没有对应的Content Provider，因此抛出文件未找到异常。

修复方案 #

调整Uri生成逻辑，先将路径字符串转为File对象，再通过Uri.fromFile()生成带有正确file://协议的Uri，修复后代码如下：

override fun click(url: String?) {
        if (url != null) {
            Glide.with(requireContext()).load(url).into(binding.userAvatar)
            val file = File(url)
            val uriAvatar = Uri.fromFile(file)
            val storageRef = storage.reference
            val avatarRef = auth.currentUser?.let { storageRef.child(it.uid).child("avatar.png") }
            val uploadTask: UploadTask = avatarRef!!.putFile(uriAvatar)
            uploadTask.addOnCompleteListener {
                if (it.isSuccessful) {
                    avatarRef.downloadUrl.addOnCompleteListener { url ->
                        user.userAvatar = url.toString()
                        Toast.makeText(context, "Upload image success!", Toast.LENGTH_SHORT).show()
                    }
                } else {
                    Toast.makeText(context, it.exception?.message, Toast.LENGTH_SHORT).show()
                    it.exception?.message?.let { it1 -> Log.e(TAG, it1) }
                }
            }
        }
    }

内容的提问来源于stack exchange，提问作者Lộc Trần Phước