Volley post只对图像和文本一起工作到mysql db

Question

我使用Volley库将4个文本和1个图像发布到mysql数据库。代码只工作一次之后，当我尝试发布时，我只获得空响应，并且在sql db中也没有看到数据。在Android清单中添加了所有必要的权限，但无法理解此代码的错误。

JAVA：

public class Main extends AppCompatActivity implements View.OnClickListener {

RadioButton radioType;
RadioGroup radioGroup;
EditText FoodName,FoodLocation,ShopName;
TextView Camera,Gallery,Post;
ImageView imageView;
private Bitmap bitmap;

private int PICK_IMAGE_REQUEST = 1;
private String UPLOAD_URL ="http://xyz.ttt.com/upload.php";

private String KEY_IMAGE = "image";
private String KEY_NAME = "FoodName";
private String KEY_LOCATION = "FoodLocation";
private String KEY_SHOP = "ShopName";
private String KEY_TYPE = "Type";

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    radioGroup = (RadioGroup)findViewById(R.id.RadioGroup);
    FoodName = (EditText)findViewById(R.id.FoodName);
    FoodLocation = (EditText)findViewById(R.id.FoodLocation);
    ShopName = (EditText)findViewById(R.id.ShopName);
    Camera = (TextView)findViewById(R.id.Camera);
    Gallery = (TextView)findViewById(R.id.Gallery);
    Post = (TextView)findViewById(R.id.Post);
    imageView=(ImageView)findViewById(R.id.image);
    Camera.setOnClickListener(this);
    Gallery.setOnClickListener(this);
    Post.setOnClickListener(this);

}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.menu_main, menu);
    return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    // Handle action bar item clicks here. The action bar will
    // automatically handle clicks on the Home/Up button, so long
    // as you specify a parent activity in AndroidManifest.xml.
    int id = item.getItemId();

    //noinspection SimplifiableIfStatement
    if (id == R.id.action_settings) {
        return true;
    }

    return super.onOptionsItemSelected(item);
}

@Override
public void onClick(View v) {
    if(v == Gallery){
        showFileChooser();
    }
    if(v == Post){
        uploadImage();
    }
}

private void showFileChooser() {
    Intent intent = new Intent();
    intent.setType("image/*");
    intent.setAction(Intent.ACTION_GET_CONTENT);
    startActivityForResult(Intent.createChooser(intent, "Select Picture"), PICK_IMAGE_REQUEST);
}

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

    if (requestCode == PICK_IMAGE_REQUEST && resultCode == RESULT_OK && data != null && data.getData() != null) {
        Uri filePath = data.getData();
        try {
            //Getting the Bitmap from Gallery
            bitmap = MediaStore.Images.Media.getBitmap(getContentResolver(), filePath);
            //Setting the Bitmap to ImageView
            imageView.setImageBitmap(bitmap);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

public String getStringImage(Bitmap bmp){
    ByteArrayOutputStream baos = new ByteArrayOutputStream();
    bmp.compress(Bitmap.CompressFormat.JPEG, 100, baos);
    byte[] imageBytes = baos.toByteArray();
    String encodedImage = Base64.encodeToString(imageBytes, Base64.DEFAULT);
    return encodedImage;
}

private void uploadImage(){
    //Showing the progress dialog
    final ProgressDialog loading = ProgressDialog.show(this,"Uploading...","Please wait...",false,false);
    StringRequest stringRequest = new StringRequest(Request.Method.POST, UPLOAD_URL,
            new Response.Listener<String>() {
                @Override
                public void onResponse(String s) {
                    //Disimissing the progress dialog
                    loading.dismiss();
                    //Showing toast message of the response
                    Toast.makeText(Main.this, s, Toast.LENGTH_LONG).show();
                }
            },
            new Response.ErrorListener() {
                @Override
                public void onErrorResponse(VolleyError volleyError) {
                    //Dismissing the progress dialog
                    loading.dismiss();

                    //Showing toast
                    Toast.makeText(Main.this, volleyError.getMessage().toString(), Toast.LENGTH_LONG).show();
                }
            }){
        @Override
        protected Map<String, String> getParams() throws AuthFailureError {
            //Converting Bitmap to String
            String image = getStringImage(bitmap);

            //Getting Image Name
            String FName = FoodName.getText().toString().trim();

            String FLocation = FoodLocation.getText().toString().trim();

            String SName = ShopName.getText().toString().trim();

            int selectedId = radioGroup.getCheckedRadioButtonId();
            radioType = (RadioButton)findViewById(selectedId);
            String rType = radioType.getText().toString().trim();


            //Creating parameters
            Map<String, String> params = new Hashtable<String, String>();

            //Adding parameters
           params.put(KEY_IMAGE, image);
            params.put(KEY_NAME, FName);
            params.put(KEY_LOCATION, FLocation);
            params.put(KEY_SHOP, SName);
            params.put(KEY_TYPE, rType);


           //returning parameters
            return params;
        }
    };

    //Creating a Request Queue
    RequestQueue requestQueue = Volley.newRequestQueue(this);

    //Adding request to the queue
    requestQueue.add(stringRequest);
} }

PHP：    

if($_SERVER['REQUEST_METHOD']=='POST'){

    $image = $_POST['image'];
            $FoodName = $_POST['FoodName'];
            $FoodLocation = $_POST['FoodLocation'];
    $ShopName = $_POST['ShopName'];
            $Type = $_POST['Type'];

    require_once('dbConnect.php');

    $sql ="SELECT id FROM foodstore ORDER BY id ASC";

    $res = mysqli_query($con,$sql);

    $id = 0;

    while($row = mysqli_fetch_array($res)){
            $id = $row['id'];
    }

    $path = "images/$id.png";

    $actualpath = "http://xyz.ttt.com/$path";

    $sql = "INSERT INTO foodstore (image,FoodName,FoodLocation,ShopName,Type) VALUES ('$actualpath','$FoodName','$FoodLocation','$ShopName','$Type')";

    if(mysqli_query($con,$sql)){
        file_put_contents($path,base64_decode($image));
        echo "Successfully Uploaded";
    }

    mysqli_close($con);
}else{
    echo "Error";
}

上述代码有什么问题？