startActivityForResult 返回数据 null

Posted 2023-04-17

【中文标题】startActivityForResult 返回数据 null

【英文标题】：startActivityForResult return data null

【发布时间】：2016-12-22 18:47:00

【问题描述】：

我尝试从相机发送图像到我的活动。我像这样从adapter 打电话给startActivityForResult：

photo.setOnClickListener(new View.OnClickListener() 
    @Override
    public void onClick(View v) 
        dialog.dismiss();
        mActivity.dispatchTakePictureIntent(part.getId());
    
);

这是 Activity 上的那个方法：

public void dispatchTakePictureIntent(String id) 
    Intent takePictureIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);

    // Ensure that there's a camera activity to handle the intent
    if (takePictureIntent.resolveActivity(getPackageManager()) != null) 
        // Create the File where the photo should go
        File photoFile = null;
        try 
            photoFile = createImageFile();
         catch (IOException ex) 
            // Error occurred while creating the File

        
        // Continue only if the File was successfully created
        if (photoFile != null) 
            Uri photoURI = FileProvider.getUriForFile(this,
                    "com.example.eltegps011.eltegps.fileprovider",
                    photoFile);
            takePictureIntent.putExtra(MediaStore.EXTRA_OUTPUT, photoURI);
            takePictureIntent.putExtra("Id",id);

            startActivityForResult(takePictureIntent, CAM_REQUEST);
        
    

这是我的onActivityResult()

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) 
    super.onActivityResult(requestCode, resultCode, data);
    if (resultCode == 2) 
        part = (Part) data.getSerializableExtra("Part");
        Log.e(TAG, "onActivityResult: ");

if(requestCode == 1313) 
    Bitmap thumbnail = (Bitmap)data.getExtras().get("data");
    String id = data.getStringExtra("Id");
    Log.e(TAG, "onActivityResult: " + id);

但是，Bitmap thumbnail = (Bitmap)data.getExtras().get("data") 是 null 并且 resultCode 始终为 -1。看起来意图没有达到activity。知道为什么吗？

【问题讨论】：

关注this它可能会帮助您找到解决方案。

// Error occurred while creating the File.而且你仍然继续，好像什么也没发生一样。你应该展示一个这样说的祝酒词然后返回。

photoFile = createImageFile()。除了检查目录是否可写外，无需创建该文件。可以直接删除。将创作留给相机应用。

感谢 greenapps ，它有效。但是，我还有一个问题 :) 当我设置这样的附加功能时： Intent intent = new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE); intent.putExtra("Id",id);只有照片是正确的，id 返回 null。你知道为什么吗？

有什么解决办法吗？

【参考方案1】：

适用于所有版本的完整演示。

对于捕获和选择图像

注意：Android 6.0 在点击后获得运行时权限，然后执行。

public class MainActivity extends Activity 

    private ImageView camera, gallery;
    File photoFile;
    Uri uri;
    private final static int RESULT_LOAD_IMAGE = 1;
    private final static int REQUEST_IMAGE_CAPTURE = 2;

    @Override
    public void onCreate(Bundle savedInstanceState) 
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        camera = (ImageView) findViewById(R.id.Img);
        gallery = (ImageView) findViewById(R.id.imageView);
        camera.setOnClickListener(new View.OnClickListener() 
            @Override
            public void onClick(View v) 
                dispatchTakePictureIntent();

            
        );
        gallery.setOnClickListener(new View.OnClickListener() 
            @Override
            public void onClick(View v) 
                Intent i = new Intent(Intent.ACTION_PICK, android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
                startActivityForResult(i, RESULT_LOAD_IMAGE);
            
        );
    

    private void dispatchTakePictureIntent() 

        Intent takePictureIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
        if (takePictureIntent.resolveActivity(getPackageManager()) != null) 
            photoFile = Environment.getExternalStoragePublicDirectory("/myimage/save.jpg");
            if (photoFile != null) 
                takePictureIntent.putExtra(MediaStore.EXTRA_OUTPUT,
                        Uri.fromFile(photoFile));
                startActivityForResult(takePictureIntent, REQUEST_IMAGE_CAPTURE);
            
        
    

    @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 = data.getData();
            String selecteadImage = getRealPathFromURI(this, data.getData());
            Toast.makeText(this, "Image path " + selecteadImage, Toast.LENGTH_LONG).show();

         else if (requestCode == REQUEST_IMAGE_CAPTURE && resultCode == RESULT_OK) 

            if (data != null && data.getData() != null) 
                String selecteadImage = getRealPathFromURI(this, data.getData());
                Toast.makeText(this, "Image path " + selecteadImage, Toast.LENGTH_LONG).show();
             else 
                if (photoFile != null) 
                    String selecteadImage = photoFile.getAbsolutePath();
                    Toast.makeText(this, "Image path " + selecteadImage, Toast.LENGTH_LONG).show();
                
            
        
    

    public String getRealPathFromURI(Context context, Uri contentUri) 
        Cursor cursor = null;
        try 
            String[] proj = MediaStore.Images.Media.DATA;
            cursor = context.getContentResolver().query(contentUri, proj, null, null, null);
            int column_index = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
            cursor.moveToFirst();
            return cursor.getString(column_index);
         finally 
            if (cursor != null) 
                cursor.close();
            
        
    

清单权限：

    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.CAMERA" />
    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />

activity_main：

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_
    android:layout_
    android:background="@drawable/image_1">


    <ImageView
        android:id="@+id/camera"
        android:layout_
        android:layout_
        android:layout_centerHorizontal="true"
        android:layout_centerVertical="true"
        android:src="@mipmap/ic_launcher" />

    <ImageView
        android:id="@+id/gallery"
        android:layout_
        android:layout_
        android:layout_below="@+id/camera"
        android:layout_centerHorizontal="true"
        android:src="@mipmap/ic_launcher" />
</RelativeLayout>