在 Parse.com 中上传图片作为后端答案

【问题标题】：Upload image in Parse.com as backend在 Parse.com 中上传图片作为后端
【发布时间】：2014-01-05 14:55:53
【问题描述】：

我能够加载图片库并在 Imageview 中显示图片。我需要将用户在 parse.com 中选择的图像保存为变黑。它是我可以使用 BitmapFactory 加载的图片路径。我在数据浏览器中创建了一个字段为文件的列。我还浏览了 Parse.com 上的教程并实施了每个步骤。但是当点击保存按钮时它不起作用。应用程序每次都崩溃。

我的代码是：

public class LoadImg extends Activity  {
private static int RESULT_LOAD_IMAGE = 1;
FrameLayout layout;
Button save ;
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    save=(Button) findViewById(R.id.button2);
    String picturePath = PreferenceManager.getDefaultSharedPreferences(this).getString("picturePath", "");
    if(!picturePath.equals(""))
    {
       ImageView imageView = (ImageView) findViewById(R.id.imageView1);
       imageView.setImageBitmap(BitmapFactory.decodeFile(picturePath));
    }        
    Button buttonLoadImage = (Button) findViewById(R.id.button1);
    buttonLoadImage.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View arg0) {
            Intent i = new Intent(
                    Intent.ACTION_PICK,
                     android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
            startActivityForResult(i, RESULT_LOAD_IMAGE);
        }
    });        
    save.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View arg0) {
            // Locate the image in res > 
            Bitmap bitmap = BitmapFactory.decodeFile("picturePath");
            // Convert it to byte
            ByteArrayOutputStream stream = new ByteArrayOutputStream();
            // Compress image to lower quality scale 1 - 100
            bitmap.compress(Bitmap.CompressFormat.PNG, 100, stream);
            byte[] image = stream.toByteArray();

            // Create the ParseFile
            ParseFile file = new ParseFile("picturePath", image);
            // Upload the image into Parse Cloud
            file.saveInBackground();

            // Create a New Class called "ImageUpload" in Parse
            ParseObject imgupload = new ParseObject("ImageUpload");

            // Create a column named "ImageName" and set the string
            imgupload.put("Image", "picturePath");

            // Create a column named "ImageFile" and insert the image
            imgupload.put("ImageFile", file);

            // Create the class and the columns
            imgupload.saveInBackground();

            // Show a simple toast message
            Toast.makeText(LoadImg.this, "Image Uploaded",Toast.LENGTH_SHORT).show();           
        }
    });
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent  data) {
    super.onActivityResult(requestCode, resultCode, data);
    if (requestCode == RESULT_LOAD_IMAGE && resultCode == RESULT_OK && null  != data) {
        Uri selectedImage = data.getData();
        String[] filePathColumn = { MediaStore.Images.Media.DATA };
        Cursor cursor = getContentResolver().query(selectedImage,
                filePathColumn, null, null, null);
        cursor.moveToFirst();
        int columnIndex = cursor.getColumnIndex(filePathColumn[0]);
        String picturePath = cursor.getString(columnIndex);
        PreferenceManager.getDefaultSharedPreferences(this).edit().putString("picturePath", picturePath).commit();
        cursor.close();
        ImageView imageView = (ImageView) findViewById(R.id.imageView1);
        imageView.setImageBitmap(BitmapFactory.decodeFile(picturePath));                        
           } 
    }}

LogCat 是：

01-05 20:43:54.678: E/JavaBinder(1298): !!! Binder 交易失败！！！ 01-05 20:44:48.418：E/AndroidRuntime(3453)：未捕获的处理程序：线程主因未捕获的异常而退出 01-05 20:44:48.428: E/AndroidRuntime(3453): java.lang.NullPointerException 01-05 20:44:48.428: E/AndroidRuntime(3453): at com.lovy.parse.LoadImg$2.onClick(LoadImg.java:56) 01-05 20:44:48.428: E/AndroidRuntime(3453): 在 android.view.View.performClick(View.java:2418) 01-05 20:44:48.428: E/AndroidRuntime(3453): 在 android.view.View.onTouchEvent(View.java:4233) 01-05 20:44:48.428: E/AndroidRuntime(3453): 在 android.widget.TextView.onTouchEvent(TextView.java:6645) 01-05 20:44:48.428: E/AndroidRuntime(3453): 在 android.view.View.dispatchTouchEvent(View.java:3763) 01-05 20:44:48.428: E/AndroidRuntime(3453): 在 android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:968) 01-05 20:44:48.428: E/AndroidRuntime(3453): 在 android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:968) 01-05 20:44:48.428: E/AndroidRuntime(3453): 在 android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:968) 01-05 20:44:48.428: E/AndroidRuntime(3453): 在 android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:968) 01-05 20:44:48.428: E/AndroidRuntime(3453): 在 android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:968) 01-05 20:44:48.428: E/AndroidRuntime(3453): 在 com.android.internal.policy.impl.PhoneWindow$DecorView.superDispatchTouchEvent(PhoneWindow.java:1659) 01-05 20:44:48.428: E/AndroidRuntime(3453): 在 com.android.internal.policy.impl.PhoneWindow.superDispatchTouchEvent(PhoneWindow.java:1107) 01-05 20:44:48.428: E/AndroidRuntime(3453): 在 android.app.Activity.dispatchTouchEvent(Activity.java:2064) 01-05 20:44:48.428: E/AndroidRuntime(3453): 在 com.android.internal.policy.impl.PhoneWindow$DecorView.dispatchTouchEvent(PhoneWindow.java:1643) 01-05 20:44:48.428: E/AndroidRuntime(3453): 在 android.view.ViewRoot.handleMessage(ViewRoot.java:1691) 01-05 20:44:48.428: E/AndroidRuntime(3453): 在 android.os.Handler.dispatchMessage(Handler.java:99) 01-05 20:44:48.428: E/AndroidRuntime(3453): 在 android.os.Looper.loop(Looper.java:123) 01-05 20:44:48.428: E/AndroidRuntime(3453): 在 android.app.ActivityThread.main(ActivityThread.java:4370) 01-05 20:44:48.428: E/AndroidRuntime(3453): 在 java.lang.reflect.Method.invokeNative(Native Method) 01-05 20:44:48.428: E/AndroidRuntime(3453): 在 java.lang.reflect.Method.invoke(Method.java:521) 01-05 20:44:48.428: E/AndroidRuntime(3453): 在 com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868) 01-05 20:44:48.428: E/AndroidRuntime(3453): 在 com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626) 01-05 20:44:48.428: E/AndroidRuntime(3453): at dalvik.system.NativeStart.main(Native Method) 01-05 20:44:48.438：E/SemcCheckin（3453）：获取故障转储级别：java.io.FileNotFoundException：/data/semc-checkin/crashdump 01-05 20:44:48.508：E/SemcCheckin（1565）：获取崩溃级别：java.io.FileNotFoundException：/data/semc-checkin/crashdump 01-05 20:44:58.378: E/ATK(2142): widget kill start

【问题讨论】：

问题是什么？
@cYrixmorten 我已经编辑了上面的问题。
你能发布 LogCat 消息吗？
@cYrixmorten 我已经编辑了代码并发布了 logcat。谢谢
com.lovy.parse.LoadImg$2.onClick(LoadImg.java:56) 处的空指针。第 56 行是什么？

标签： android image parse-platform

【解决方案1】：

save.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View arg0) {
            // Locate the image in res > 
            //Bitmap bitmap = BitmapFactory.decodeFile("picturePath");
            // Convert it to byte
            //ByteArrayOutputStream stream = new ByteArrayOutputStream();
            // Compress image to lower quality scale 1 - 100
            //bitmap.compress(Bitmap.CompressFormat.PNG, 100, stream);

            try {
                image = readInFile(path);
            }
            catch(Exception e) { 
                e.printStackTrace();
            }

            // Create the ParseFile
            ParseFile file = new ParseFile("picturePath", image);
            // Upload the image into Parse Cloud
            file.saveInBackground();

            // Create a New Class called "ImageUpload" in Parse
            ParseObject imgupload = new ParseObject("Image");

            // Create a column named "ImageName" and set the string
            imgupload.put("Image", "picturePath");


            // Create a column named "ImageFile" and insert the image
            imgupload.put("ImageFile", file);

            // Create the class and the columns
            imgupload.saveInBackground();

            // Show a simple toast message
            Toast.makeText(LoadImg.this, "Image Saved, Upload another one ",Toast.LENGTH_SHORT).show(); 

        }
    });
}

private byte[] readInFile(String path) throws IOException {
    // TODO Auto-generated method stub
    byte[] data = null;
    File file = new File(path);
    InputStream input_stream = new BufferedInputStream(new FileInputStream(
            file));
    ByteArrayOutputStream buffer = new ByteArrayOutputStream();
    data = new byte[16384]; // 16K
    int bytes_read;
    while ((bytes_read = input_stream.read(data, 0, data.length)) != -1) {
        buffer.write(data, 0, bytes_read);
    }
    input_stream.close();
    return buffer.toByteArray();

}

【讨论】：

【解决方案2】：

还没有 LogCat，但我怀疑：

Bitmap bitmap = BitmapFactory.decodeResource(getResources(),R.id.imageView1);

导致问题，因为 R.id.imageView1 是视图的 id 而不是图像资源。

你可以试试这个：

Bitmap bitmap = decodeFile(picturePath);

if (bitmap != null) {
   // ...
}

注意：

你也有这个：

// Create a column named "ImageName" and set the string
imgupload.put("Image", R.id.imageView1);

从评论中，您的意图是保存一个字符串，但实际上您保存了 id 整数。

【讨论】：