将Url转换为Uri并将其传递给AsyncTask<>

本文介绍了将Url转换为Uri并将其传递给AsyncTask<>的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！

问题描述

我正在按以下方式将Url转换为Uri

I am converting a Url to Uri in the following way

imgUrl = intent.getStringExtra(getString(R.string.selected_image));
            Log.d(TAG, "Image URL" + imgUrl);
                imageUri = Uri.parse(imgUrl) ;
            Log.d(TAG, "Image URI" + imageUri);

然后将其传递给此函数

 BackgroundImageResize backgroundImageResize = new BackgroundImageResize(bitmap);
           backgroundImageResize.execute(imageUri);

和BackgroundImageResize将参数视为

and BackgroundImageResize takes arguments as

public class BackgroundImageResize extends AsyncTask<Uri, Integer, byte[]>

现在这个方法

Log.d(TAG, "doInBackground: megabytes before compression: " + mBitmap.getByteCount() / 1000000 );
        bytes = getBytesFromBitmap(mBitmap, 100);
        Log.d(TAG, "doInBackground: megabytes before compression: " + bytes.length / 1000000 );

返回此错误

Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'int android.graphics.Bitmap.getByteCount()' on a null object reference

在之前与一个非常聪明的人的讨论中，已经得出结论，也许，Uri是不正确的

in previous discussions with a really smart person, it has been concluded that, maybe, the Uri is incorrect

如何传递正确的Uri？

这是doInBackground（）以防万一

this is the doInBackground() just in case

@Override
    protected byte[] doInBackground(Uri... params) {
        Log.d(TAG, "doInBackground: started.");

        if(mBitmap == null){
            try{
                mBitmap = MediaStore.Images.Media.getBitmap(NextActivity.this.getContentResolver(), params[0]);
            }catch (IOException e){
                Log.e(TAG, "doInBackground: IOException: " + e.getMessage());
            }
        }
        byte[] bytes = null;
        Log.d(TAG, "doInBackground: megabytes before compression: " + mBitmap.getByteCount() / 1000000 );
        bytes = getBytesFromBitmap(mBitmap, 100);
        Log.d(TAG, "doInBackground: megabytes before compression: " + bytes.length / 1000000 );
        return bytes;
    }

我怀疑这行代码

mBitmap = MediaStore.Images.Media.getBitmap(NextActivity.this.getContentResolver(), params[0]);

没有做好工作：P

推荐答案

请在doInBackGround（）中添加带有+++++++++++++++++++++++++++++++ b $ b

Please add the 2 Logs with the ++++++++++++ lines in your doInBackGround() and post your Logcat:

@Override
protected byte[] doInBackground(Uri... params) {
    Log.d(TAG, "doInBackground: started.");

    Log.d(TAG, "+++++++++++++ params[0]: " + params[0]);

    if(mBitmap == null){
        try{
            mBitmap = MediaStore.Images.Media.getBitmap(NextActivity.this.getContentResolver(), params[0]);
        }catch (IOException e){
            Log.e(TAG, "doInBackground: IOException: " + e.getMessage());
        }
    }

    Log.d(TAG, "+++++++++++++ mBitmap: " + mBitmap);

    byte[] bytes = null;
    Log.d(TAG, "doInBackground: megabytes before compression: " + mBitmap.getByteCount() / 1000000 );
    bytes = getBytesFromBitmap(mBitmap, 100);
    Log.d(TAG, "doInBackground: megabytes before compression: " + bytes.length / 1000000 );
    return bytes;
}

这篇关于将Url转换为Uri并将其传递给AsyncTask<>的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！

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