Question

我正在构建一个Android应用程序，并且有五个Activity类，或者如果您熟悉MVC模式，它们通常是Controller类。

具体而言，User将进入这5个Activity课程中的一个（通过在整个应用中导航），有时他们可能会上传照片。现在，上传照片的代码遵循非常相似的模式。请注意所有这5个等级（YUCK）中所有这些代码重复5次。

全局变量：

/*
Tracking
 */
private static final int TAKE_PHOTO_REQUEST = 1;
private static final int GET_FROM_GALLERY = 2;

private Uri mUri;
private String mCurrentPhotoPath;
private File mFile;
private TypedFile mTypedFile; // For Retrofit

用户点击照片上传按钮，会弹出AlertDialog：

private void showFileOptions() {
    new AlertDialog.Builder(this)
            .setItems(R.array.uploadOptions, new DialogInterface.OnClickListener() {
                @Override
                public void onClick(DialogInterface dialog, int which) {
                    switch (which) {
                        case 0:
                            dispatchTakePicture();
                            break;
                        case 1:
                            dispatchUploadFromGallery();
                            break;
                    }
                }
            })
            .setNegativeButton(android.R.string.cancel, new DialogInterface.OnClickListener() {
                @Override
                public void onClick(DialogInterface dialog, int which) {
                    dialog.cancel();
                }
            })
            .show();
}

dispatchTakePicture：

/*
Take picture from your camera
 */
private void dispatchTakePicture() {
    Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
    // Make sure that there is a camera activity to handle the intent
    if (intent.resolveActivity(getPackageManager()) != null) {

        // Create the File where the mTypedFile would go
        File picFile = null;

        try {
            picFile = createImageFile();
            mFile = picFile;
        } catch (IOException e) {
            e.printStackTrace();
            Toast.makeText(this, e.getMessage(), Toast.LENGTH_LONG).show();
        }

        // Continue only if the file was successfully created
        if (picFile != null) {
            intent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(picFile));
            startActivityForResult(intent, TAKE_PHOTO_REQUEST);
        }
    }
}

dispatchUploadFromGallery：

/*
Take a mTypedFile from your gallery
 */
private void dispatchUploadFromGallery() {
    // Launch gallery intent
    startActivityForResult(new Intent(Intent.ACTION_PICK, MediaStore
            .Images.Media.INTERNAL_CONTENT_URI), GET_FROM_GALLERY);
}

请注意，在这两种方法中都会调用startActivityForResult。如果用户想要从createImageFile() API中拍照，则可以使用Camera方法：

private File createImageFile() throws IOException {
    // Create the Image File name
    String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss", Locale.getDefault()).format(new Date());
    String imageFileName = "JPEG_" + timeStamp + "_";

    File storageDir = Environment
            .getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES);

    File image = File.createTempFile(
            imageFileName, // Prefix
            ".jpg", // Suffix
            storageDir // Directory
    );

    // Save the file, path for ACTION_VIEW intents
    mCurrentPhotoPath = "file:" + image.getAbsolutePath();
    mUri = Uri.fromFile(image);

    return image;
}

现在终于我们的startActivityForResult(...)方法：

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


    if (requestCode == TAKE_PHOTO_REQUEST && resultCode == RESULT_OK) {
        startUploadProgress();
        showContainer();

        mTypedFile = new TypedFile("image/*", mFile);
        RotatePictureHelper.rotatePicture(mFile, ExampleActivity.this, mAttachment); // Helper class to rotate pictures
        mBus.post(new LoadUploadFileEvent(mTypedFile));

    } else if (requestCode == GET_FROM_GALLERY && resultCode == RESULT_OK) {
        startUploadProgress();
        showContainer();

        mUri = data.getData();
        mTypedFile = UriHelper.handleUri(mUri, this); // Helper class to handle bitmap manipulation
        mFile = mTypedFile.file();
        mBus.post(new LoadUploadFileEvent(mTypedFile));
    } else if (resultCode != Activity.RESULT_CANCELED) {
        Toast.makeText(this, R.string.generalError, Toast.LENGTH_LONG).show();
    }
}

请注意，我已经创建了帮助程序类来处理位图操作和图片旋转问题。

但是，这是一个非常难看的丑陋代码，并且在5个类中重复这个。

我现在想到了一些想法：

创建服务并将所需的变量传递给该服务以处理此问题。
将AlertDialog选项移至帮助程序类，并根据AlertDialogs调用instanceOf调用不同的Activity。
我应该创建一个具有这些方法的父Activity类，然后扩展5个Activity子类并调用这些方法吗？

Answer 1

创建一个扩展DialogFragment的片段（例如UploadPhotoFragment），覆盖onCreateDialog和onActivityResult方法。当需要时，请致电

{{1}}

Ps：如果您使用的是支持库，请使用支持库的DialogFragment和FragmentManager。

Answer 2

要解决这个问题，我选择了第三个选项：

我创建了一个名为lookup = {} b.each_with_index { |el, i| lookup[el] = i } a.sort_by { |el| lookup.fetch(el.first) } # => [["A", 1075000], ["B", 0], ["C", 1750000], ["D", 0], ["E", 0]]的活动，然后在我的其他5个CameraActivity课程中扩展了此Activity。这些类中的每个类的代码都是95％相似，每个类别的差异可能分别为5％。

我的Activity会有以下代码：

CameraActivity

现在，我可以在我的其他public class CameraActivity extends Activity { /* Tracking */ private static final int TAKE_PHOTO_REQUEST = 1; private static final int GET_FROM_GALLERY = 2; private Uri mUri; private String mCurrentPhotoPath; private File mFile; private TypedFile mTypedFile; // For Retrofit @Override protected void onActivityResult(int requestCode, int resultCode, Intent data) { super.onActivityResult(requestCode, resultCode, data); startProgress(); switch (requestCode) { case TAKE_PHOTO_REQUEST: if (resultCode == RESULT_OK) { mTypedFile = new TypedFile("image/*", mFile); } break; case GET_FROM_GALLERY: if (resultCode == RESULT_OK) { mUri = data.getData(); mTypedFile = UriHelper.handleUri(mUri, this); } break; default: stopProgress(); Toast.makeText(this, R.string.generalError, Toast.LENGTH_LONG).show(); break; } } protected void showFileOptions() { new AlertDialog.Builder(this) .setItems(R.array.uploadOptions, new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialog, int which) { switch (which) { case 0: dispatchTakePicture(); break; case 1: dispatchUploadFromGallery(); break; default: dispatchUploadFromGallery(); break; } } }) .setNegativeButton(android.R.string.cancel, new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialog, int which) { dialog.cancel(); } }) .show(); } // Other code for handling Uri and File goes here.... }课程中扩展此Activity，并实现其余的5％差异。请注意Activity已更改为showFileOptions()状态，因此我可以从孩子protected拨打该电话。举个例子就是一个活动。

Activity

现在我可以简单地扩展我的5个孩子public class PhotoUploadActivity extends CameraActivity { // Initialize methods @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); showFileOptions(); // Calling AlertDialog from Parent Activity } @Override public void onActivityResult(int requestCode, int resultCode, Intent data) { // Super call executes code in CameraActivity super.onActivityResult(requestCode, resultCode, data); switch (requestCode) { case TAKE_PHOTO_REQUEST: if (resultCode == RESULT_OK) { // Implement logic if user take a photo, do something with mUri or mTypedFile } break; case GET_FROM_GALLERY: if (resultCode == RESULT_OK) { // Implement logic if user gets something from gallery, do something with mUri or mTypedFile } break; default: break; } } }课程，在这些课程中调用Activity，并考虑剩余的5％代码，而super.onActivityResult(...)处理其余的代码。

照片上传的设计实现

2 个答案: