Question

我正在尝试将图像发送到我的服务器。我是通过查看LINK

中的教程来做到这一点的

然而，我需要发送从相机拍摄的照片，而不是来自画廊，所以我做了一些更改，我得到这样的错误：

致命的例外：主要处理：com.example.audriusalekna.camerapht，PID：25792 java.lang.RuntimeException：将结果ResultInfo {who = null，request = 1，result = -1，data = Intent {act = inline-data（has extras）}}传递给activity {com.example.audriusalekna.camerapht / com.example.audriusalekna.camerapht.MainActivity}：java.lang.NullPointerException：尝试调用虚方法'boolean android.graphics.Bitmap.compress（android.graphics.Bitmap $ CompressFormat，int，java.io.OutputStream）'on空对象引用在android.app.ActivityThread.deliverResults（ActivityThread.java:3887）在android.app.ActivityThread.handleSendResult（ActivityThread.java:3930）在android.app.ActivityThread.access $ 1300（ActivityThread.java:178）在android.app.ActivityThread $ H.handleMessage（ActivityThread.java:1561）在android.os.Handler.dispatchMessage（Handler.java:111）在android.os.Looper.loop（Looper.java:194）在android.app.ActivityThread.main（ActivityThread.java:5692） at java.lang.reflect.Method.invoke（Native Method）在java.lang.reflect.Method.invoke（Method.java:372）在com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run（ZygoteInit.java:959）在com.android.internal.os.ZygoteInit.main（ZygoteInit.java:754）引起：java.lang.NullPointerException：尝试在空对象引用上调用虚方法'boolean android.graphics.Bitmap.compress（android.graphics.Bitmap $ CompressFormat，int，java.io.OutputStream）' 在com.example.audriusalekna.camerapht.MainActivity.onActivityResult（MainActivity.java:70）在android.app.Activity.dispatchActivityResult（Activity.java:6346）在android.app.ActivityThread.deliverResults（ActivityThread.java:3883）在android.app.ActivityThread.handleSendResult（ActivityThread.java:3930）在android.app.ActivityThread.access $ 1300（ActivityThread.java:178）在android.app.ActivityThread $ H.handleMessage（ActivityThread.java:1561）在android.os.Handler.dispatchMessage（Handler.java:111）在android.os.Looper.loop（Looper.java:194）在android.app.ActivityThread.main（ActivityThread.java:5692） at java.lang.reflect.Method.invoke（Native Method）在java.lang.reflect.Method.invoke（Method.java:372）

我在MainActivity的代码在这里：

package com.example.audriusalekna.camerapht;

import android.app.Activity;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.PorterDuff;
import android.graphics.PorterDuffXfermode;
import android.net.Uri;
import android.provider.MediaStore;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Base64;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.Toast;

import com.android.volley.AuthFailureError;
import com.android.volley.Request;
import com.android.volley.RequestQueue;
import com.android.volley.Response;
import com.android.volley.VolleyError;
import com.android.volley.toolbox.StringRequest;
import com.android.volley.toolbox.Volley;

import java.io.ByteArrayOutputStream;
import java.util.HashMap;
import java.util.Map;

import static android.R.attr.bitmap;
import static android.R.attr.x;
import static android.R.attr.y;
import static android.provider.ContactsContract.CommonDataKinds.Website.URL;


public class MainActivity extends AppCompatActivity {
    static final int REQUEST_IMAGE_CAPTURE = 1;
    private Uri fileUri;
    private ImageView imageView;
    Bitmap bitmap;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        Button cameraBtn = (Button) findViewById(R.id.push_button);
        imageView = (ImageView)findViewById(R.id.imageTest);

        cameraBtn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent cameraIntent = new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE);
                startActivityForResult(cameraIntent, REQUEST_IMAGE_CAPTURE);
            }
        });
    }

    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        if (requestCode == REQUEST_IMAGE_CAPTURE && resultCode == Activity.RESULT_OK) {
            Bitmap photo = (Bitmap) data.getExtras().get("data");
            imageView.setImageBitmap(photo);

            ByteArrayOutputStream baos = new ByteArrayOutputStream();
            bitmap.compress(Bitmap.CompressFormat.JPEG, 100, baos);
            byte[] imageBytes = baos.toByteArray();
            final String imageString = Base64.encodeToString(imageBytes, Base64.DEFAULT);

            //sending image to server
            StringRequest request = new StringRequest(Request.Method.POST, URL, new Response.Listener<String>(){
                @Override
                public void onResponse(String s) {

                    if(s.equals("true")){
                        Toast.makeText(MainActivity.this, "Uploaded Successful", Toast.LENGTH_LONG).show();
                    }
                    else{
                        Toast.makeText(MainActivity.this, "Some error occurred!", Toast.LENGTH_LONG).show();
                    }
                }
            },new Response.ErrorListener(){
                @Override
                public void onErrorResponse(VolleyError volleyError) {
                    Toast.makeText(MainActivity.this, "Some error occurred -> "+volleyError, Toast.LENGTH_LONG).show();;
                }
            }) {
                //adding parameters to send
                @Override
                protected Map<String, String> getParams() throws AuthFailureError {
                    Map<String, String> parameters = new HashMap<String, String>();
                    parameters.put("image", imageString);
                    return parameters;
                }
            };

            RequestQueue rQueue = Volley.newRequestQueue(MainActivity.this);
            rQueue.add(request);

        }
        if (requestCode == REQUEST_IMAGE_CAPTURE && resultCode == RESULT_OK && data != null && data.getData() != null) {
            Uri filePath = data.getData();

            try {
                //getting image from gallery
                bitmap = MediaStore.Images.Media.getBitmap(getContentResolver(), filePath);

                //Setting image to ImageView
                imageView.setImageBitmap(bitmap);
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }
}

Answer 1

你的位图为空，为了做你想要的你需要保存文件localy而不是发送它。在调用相机意图的Onclick上执行以下操作：

 Intent cameraIntent = new Intent("android.media.action.IMAGE_CAPTURE");
 File file = new File(YOUR_FILE_PATH + "/FILE.jpg");
 cameraIntent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(file));
 startActivityForResult(cameraIntent, REQUEST_IMAGE_CAPTURE);

以后onresult从这样的路径中取出文件：

File f = new  File(YOUR_FILE_PATH + "/FILE.jpg");
Bitmap bitmap=null;
BitmapFactory.Options options = new BitmapFactory.Options();
options.inPreferredConfig = Bitmap.Config.ARGB_8888;
try {
   bitmap = BitmapFactory.decodeStream(new FileInputStream(f), null, options);
} catch (FileNotFoundException e) {
     e.printStackTrace();
}
imageView.setImageBitmap(bitmap);

希望它有所帮助。

Answer 2

@greenapps解决方案有效！我刚刚更改了bitmap.compress（Bitmap.CompressFormat.JPEG，100，baos）; to photo.compress（Bitmap.CompressFormat.JPEG，100，baos）;

从相机错误

2 个答案: