android - ストレージ アクセス フレームワーク

Question

Storage Access Framework を使用してファイルを削除しようとしましたが、deleteDocument は常に false を返します。私は Android 5.0 を搭載した Asus zenfone 5 を持っていますが、contentprovider と uri が正しいかどうか疑問に思っています。uri は SDCard(/storage/MicroSD/test123123.apk) からのパスです。

String t = "";
void deleteFunc(String filepath) {
     t = filepath;
     Intent intent = new Intent("android.intent.action.OPEN_DOCUMENT_TREE");
     intent.putExtra("android.content.extra.SHOW_ADVANCED", true);
         startActivityForResult(intent, 1);
}



@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);

    Toast.makeText(this, "S: " + data.getData(), Toast.LENGTH_SHORT).show();
    Toast.makeText(this, "D: " + t, Toast.LENGTH_SHORT).show();
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
            DocumentFile test = DocumentFile.fromFile(new File(t));

            DocumentsContract.deleteDocument(getApplicationContext().getContentResolver(), Uri.parse(t));
            Toast.makeText(this, "P: " + test.delete(), Toast.LENGTH_SHORT).show();
            Toast.makeText(this, "T: " + DocumentsContract.deleteDocument(getApplicationContext().getContentResolver(), Uri.parse(t)), Toast.LENGTH_SHORT).show();
            }
        }

---

これは deleteDocument の例外です

09-23 11:46:13.054  8216  8216 W Documents: Failed to delete document
    09-23 11:46:13.054  8216  8216 W Documents: java.lang.NullPointerException: Attempt to invoke virtual method 'android.os.Bundle android.content.ContentProviderClient.call(java.lang.String, java.lang.String, android.os.Bundle)' on a null object reference
    09-23 11:46:13.054  8216  8216 W Documents:     at android.provider.DocumentsContract.deleteDocument(DocumentsContract.java:987)
    09-23 11:46:13.054  8216  8216 W Documents:     at android.provider.DocumentsContract.deleteDocument(DocumentsContract.java:971)
    09-23 11:46:13.054  8216  8216 W Documents:     at com.test.example.ResultActivity.onActivityResult(SourceFile:364)
    09-23 11:46:13.054  8216  8216 W Documents:     at android.app.Activity.dispatchActivityResult(Activity.java:6177)
    09-23 11:46:13.054  8216  8216 W Documents:     at android.app.ActivityThread.deliverResults(ActivityThread.java:3551)
    09-23 11:46:13.054  8216  8216 W Documents:     at android.app.ActivityThread.handleSendResult(ActivityThread.java:3598)
    09-23 11:46:13.054  8216  8216 W Documents:     at android.app.ActivityThread.access$1300(ActivityThread.java:147)
    09-23 11:46:13.054  8216  8216 W Documents:     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1330)
    09-23 11:46:13.054  8216  8216 W Documents:     at android.os.Handler.dispatchMessage(Handler.java:102)
    09-23 11:46:13.054  8216  8216 W Documents:     at android.os.Looper.loop(Looper.java:135)
    09-23 11:46:13.054  8216  8216 W Documents:     at android.app.ActivityThread.main(ActivityThread.java:5253)
    09-23 11:46:13.054  8216  8216 W Documents:     at java.lang.reflect.Method.invoke(Native Method)
    09-23 11:46:13.054  8216  8216 W Documents:     at java.lang.reflect.Method.invoke(Method.java:372)
    09-23 11:46:13.054  8216  8216 W Documents:     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
    09-23 11:46:13.054  8216  8216 W Documents:     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)