Android拍照或者選取本地圖片

總體流程

從selectPhotoActivity中啓動圖冊或者相機，再根據獲取的uri進行裁剪，返回uri，再對這個uri執行一系列操縱。

從相冊選取圖片

private void pickPhoto() {
        Intent intent = new Intent(Intent.ACTION_PICK,
                android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
        startActivityForResult(intent, SELECT_PIC_BY_PICK_PHOTO);
    }

使用隱式intent啓動相機。

拍照獲取圖片

private void takePhoto() {
        // 執行拍照前，應該先判斷SD卡是否存在
        String SDState = Environment.getExternalStorageState();
        if (SDState.equals(Environment.MEDIA_MOUNTED)) {
            Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);// "android.media.action.IMAGE_CAPTURE"
            File path = Environment
                    .getExternalStoragePublicDirectory(Environment.DIRECTORY_DCIM);
            File file = new File(path, IMAGE_FILE_NAME);
            takePhoto = Uri.fromFile(file);
            intent.putExtra(android.provider.MediaStore.EXTRA_OUTPUT, takePhoto);
            startActivityForResult(intent, SELECT_PIC_BY_TACK_PHOTO);
        } else {
            Toast.makeText(getApplicationContext(), "內存卡不存在",
                    Toast.LENGTH_SHORT).show();
        }
    }

值得注意的一點是，intent.putExtra(android.provider.MediaStore.EXTRA_OUTPUT, takePhoto)中，設置了拍完照照片的存放路徑takePhoto，在此情況下，部分機型的onActivityResult()中不會返回數據，即data.getData()爲空，因爲可以根據存放路徑即可獲取拍照圖片。

裁剪圖片

public void startPhotoZoom(Uri uri) {
        Intent intent = new Intent("com.android.camera.action.CROP");
        intent.setDataAndType(uri, "image/*");
        // 設置裁剪
        intent.putExtra("crop", "true");
        // aspectX aspectY 是寬高的比例
        intent.putExtra("aspectX", 1);
        intent.putExtra("aspectY", 1);
        // outputX outputY 是裁剪圖片寬高
        intent.putExtra("outputX", 340);
        intent.putExtra("outputY", 340);
        //將URI指向相應的file:///…
        intent.putExtra(MediaStore.EXTRA_OUTPUT, uri);
        // 不返回圖片文件
        intent.putExtra("return-data", false);
        startActivityForResult(intent, RESULT_REQUEST_CODE);
    }

裁剪方法調用android自帶的裁剪庫，部分深度定製的機型，如魅族，可能不存在該庫，那麼就需要自定義或者使用開源裁剪庫。

返回的數據的處理

protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        if (resultCode != Activity.RESULT_OK) {
            Log.e("TAG","ActivityResult resultCode error");
            return;
        }

        switch (requestCode){
            case SELECT_PIC_BY_PICK_PHOTO:
                Uri uri = data.getData();
                if (!TextUtils.isEmpty(uri.getAuthority())) {
                    //查詢選擇圖片
                    Cursor cursor = getContentResolver().query(
                        uri,
                        new String[] { MediaStore.Images.Media.DATA },
                        null,
                        null,
                        null);
                    //返回 沒找到選擇圖片
                    if (null == cursor) {
                        return;
                    }
                    //光標移動至開頭 獲取圖片路徑
                    cursor.moveToFirst();
                    picPath = cursor.getString(cursor
                        .getColumnIndex(MediaStore.Images.Media.DATA));
                    Log.d("圖片路徑啊啊啊啊啊啊",picPath);
                }
                break;
            case SELECT_PIC_BY_TACK_PHOTO:
                //裁剪圖片
                startPhotoZoom(takePhoto);
                break;
            case RESULT_REQUEST_CODE :
                if (data != null) {
                    Log.d("圖片路徑",data.getData().toString());
                    picPath = getPathByUri4kitkat(getApplicationContext(),data.getData());
                    Log.d("圖片路徑啊啊啊啊啊啊",picPath);
                }
                break;
        }
        if(requestCode != SELECT_PIC_BY_TACK_PHOTO) {
            lastIntent.putExtra(KEY_PHOTO_PATH, picPath);
            setResult(Activity.RESULT_OK, lastIntent);
            finish();
        }
        super.onActivityResult(requestCode, resultCode, data);

    }

因爲在本activity中可能啓動三個新的activity，即拍照activity，相冊activity，裁剪activity。需要注意，拍完照的圖片需要經過裁剪，即，只有從相冊選取和裁剪返回的數據可以setRuselt()，故需要添加一個if語句加以判別。

根據Uri獲取真實路徑

還是因爲機型適配的問題，以下提供兩種方法，大家自己嘗試：

方法一

public static String getRealPathFromURI(final Context context, final Uri uri ) {
        if ( null == uri ) return null;
        final String scheme = uri.getScheme();
        String data = null;
        if ( scheme == null )
            data = uri.getPath();
        else if ( ContentResolver.SCHEME_FILE.equals( scheme ) ) {
            data = uri.getPath();
        } else if ( ContentResolver.SCHEME_CONTENT.equals( scheme ) ) {
            Cursor cursor = context.getContentResolver().query( uri, new String[] { MediaStore.Images.ImageColumns.DATA }, null, null, null );
            if ( null != cursor ) {
                if ( cursor.moveToFirst() ) {
                    int index = cursor.getColumnIndex( MediaStore.Images.ImageColumns.DATA );
                    if ( index > -1 ) {
                        data = cursor.getString( index );
                    }
                }
                cursor.close();
            }
        }
        return data;
    }

方法二

 @SuppressLint("NewApi")
    public static String getPathByUri4kitkat(final Context context, final Uri uri) {
        final boolean isKitKat = Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT;
        // DocumentProvider
        if (isKitKat && DocumentsContract.isDocumentUri(context, uri)) {
            if (isExternalStorageDocument(uri)) {// ExternalStorageProvider
                final String docId = DocumentsContract.getDocumentId(uri);
                final String[] split = docId.split(":");
                final String type = split[0];
                if ("primary".equalsIgnoreCase(type)) {
                    return Environment.getExternalStorageDirectory() + "/" + split[1];
                }
            } else if (isDownloadsDocument(uri)) {// DownloadsProvider
                final String id = DocumentsContract.getDocumentId(uri);
                final Uri contentUri = ContentUris.withAppendedId(Uri.parse("content://downloads/public_downloads"),
                        Long.valueOf(id));
                return getDataColumn(context, contentUri, null, null);
            } else if (isMediaDocument(uri)) {// MediaProvider
                final String docId = DocumentsContract.getDocumentId(uri);
                final String[] split = docId.split(":");
                final String type = split[0];
                Uri contentUri = null;
                if ("image".equals(type)) {
                    contentUri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI;
                } else if ("video".equals(type)) {
                    contentUri = MediaStore.Video.Media.EXTERNAL_CONTENT_URI;
                } else if ("audio".equals(type)) {
                    contentUri = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
                }
                final String selection = "_id=?";
                final String[] selectionArgs = new String[] { split[1] };
                return getDataColumn(context, contentUri, selection, selectionArgs);
            }
        } else if ("content".equalsIgnoreCase(uri.getScheme())) {// MediaStore
            // (and
            // general)
            return getDataColumn(context, uri, null, null);
        } else if ("file".equalsIgnoreCase(uri.getScheme())) {// File
            return uri.getPath();
        }
        return null;
    }

    /**
     * Get the value of the data column for this Uri. This is useful for
     * MediaStore Uris, and other file-based ContentProviders.
     *
     * @param context
     *            The context.
     * @param uri
     *            The Uri to query.
     * @param selection
     *            (Optional) Filter used in the query.
     * @param selectionArgs
     *            (Optional) Selection arguments used in the query.
     * @return The value of the _data column, which is typically a file path.
     */
    public static String getDataColumn(Context context, Uri uri, String selection, String[] selectionArgs) {
        Cursor cursor = null;
        final String column = "_data";
        final String[] projection = { column };
        try {
            cursor = context.getContentResolver().query(uri, projection, selection, selectionArgs, null);
            if (cursor != null && cursor.moveToFirst()) {
                final int column_index = cursor.getColumnIndexOrThrow(column);
                return cursor.getString(column_index);
            }
        } finally {
            if (cursor != null)
                cursor.close();
        }
        return null;
    }

    /**
     * @param uri
     *            The Uri to check.
     * @return Whether the Uri authority is ExternalStorageProvider.
     */
    public static boolean isExternalStorageDocument(Uri uri) {
        return "com.android.externalstorage.documents".equals(uri.getAuthority());
    }

    /**
     * @param uri
     *            The Uri to check.
     * @return Whether the Uri authority is DownloadsProvider.
     */
    public static boolean isDownloadsDocument(Uri uri) {
        return "com.android.providers.downloads.documents".equals(uri.getAuthority());
    }

    /**
     * @param uri
     *            The Uri to check.
     * @return Whether the Uri authority is MediaProvider.
     */
    public static boolean isMediaDocument(Uri uri) {
        return "com.android.providers.media.documents".equals(uri.getAuthority());
    }

整體代碼

public class selectPhotoActivity extends Activity implements View.OnClickListener{

    /** 使用照相機拍照獲取圖片 */
    public static final int SELECT_PIC_BY_TACK_PHOTO = 1;
    /** 使用相冊中的圖片 */
    public static final int SELECT_PIC_BY_PICK_PHOTO = 2;
    /** 裁剪圖片 */
    private static final int RESULT_REQUEST_CODE = 3;
    /** 開啓相機 */
    private Button btn_take_photo;
    /** 開啓圖冊 */
    private Button btn_pick_photo;
    /** 取消 */
    private Button btn_cancel;
    /** 圖片名稱 */
    private static final String IMAGE_FILE_NAME = "image.jpg";
    /** 獲取到的圖片路徑 */
    private String picPath;
    //保存裁剪後的圖像
    private Bitmap photo;
    private Intent lastIntent;
    private Uri takePhoto;
    /** 從Intent獲取圖片路徑的KEY */
    public static final String KEY_PHOTO_PATH = "photo_path";
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_select_photo);

        btn_take_photo = (Button) findViewById(R.id.btn_take_photo);
        btn_pick_photo = (Button) findViewById(R.id.btn_pick_photo);
        btn_cancel = (Button) findViewById(R.id.btn_cancel);

        lastIntent = getIntent();

        btn_take_photo.setOnClickListener(this);
        btn_pick_photo.setOnClickListener(this);
        btn_cancel.setOnClickListener(this);
    }

    @Override
    public void onClick(View v) {
        switch (v.getId()) {
            case R.id.btn_take_photo : // 開啓相機
                takePhoto();
                break;
            case R.id.btn_pick_photo : // 開啓圖冊
                pickPhoto();
                break;
            case R.id.btn_cancel : // 取消操作
                this.finish();
                break;
            default :
                break;
        }
    }

    /**
     * 拍照獲取圖片
     */
    private void takePhoto() {
        // 執行拍照前，應該先判斷SD卡是否存在
        String SDState = Environment.getExternalStorageState();
        if (SDState.equals(Environment.MEDIA_MOUNTED)) {
            Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);// "android.media.action.IMAGE_CAPTURE"
            File path = Environment
                    .getExternalStoragePublicDirectory(Environment.DIRECTORY_DCIM);
            File file = new File(path, IMAGE_FILE_NAME);
            takePhoto = Uri.fromFile(file);
            intent.putExtra(android.provider.MediaStore.EXTRA_OUTPUT, takePhoto);
            startActivityForResult(intent, SELECT_PIC_BY_TACK_PHOTO);
        } else {
            Toast.makeText(getApplicationContext(), "內存卡不存在",
                    Toast.LENGTH_SHORT).show();
        }
    }

    /***
     * 從相冊中取圖片
     */
    private void pickPhoto() {
        Intent intent = new Intent(Intent.ACTION_PICK,
                android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
        startActivityForResult(intent, SELECT_PIC_BY_PICK_PHOTO);
    }

    @Override
    public boolean onTouchEvent(MotionEvent event) {
        finish();
        return super.onTouchEvent(event);
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        if (resultCode != Activity.RESULT_OK) {
            Log.e("TAG","ActivityResult resultCode error");
            return;
        }

        switch (requestCode){
            case SELECT_PIC_BY_PICK_PHOTO:
                Uri uri = data.getData();
                if (!TextUtils.isEmpty(uri.getAuthority())) {
                    //查詢選擇圖片
                    Cursor cursor = getContentResolver().query(
                        uri,
                        new String[] { MediaStore.Images.Media.DATA },
                        null,
                        null,
                        null);
                    //返回 沒找到選擇圖片
                    if (null == cursor) {
                        return;
                    }
                    //光標移動至開頭 獲取圖片路徑
                    cursor.moveToFirst();
                    picPath = cursor.getString(cursor
                        .getColumnIndex(MediaStore.Images.Media.DATA));
                    Log.d("圖片路徑啊啊啊啊啊啊",picPath);
                }
                break;
            case SELECT_PIC_BY_TACK_PHOTO:
                //裁剪圖片
                startPhotoZoom(takePhoto);
                break;
            case RESULT_REQUEST_CODE :
                if (data != null) {
                    Log.d("圖片路徑",data.getData().toString());
                    picPath = getPathByUri4kitkat(getApplicationContext(),data.getData());
                    Log.d("圖片路徑啊啊啊啊啊啊",picPath);
                }
                break;
        }
        if(requestCode != SELECT_PIC_BY_TACK_PHOTO) {
            lastIntent.putExtra(KEY_PHOTO_PATH, picPath);
            setResult(Activity.RESULT_OK, lastIntent);
            finish();
        }
        super.onActivityResult(requestCode, resultCode, data);

    }

    /**
     * 裁剪圖片方法實現
     *
     * @param uri
     */
    public void startPhotoZoom(Uri uri) {
        Intent intent = new Intent("com.android.camera.action.CROP");
        intent.setDataAndType(uri, "image/*");
        // 設置裁剪
        intent.putExtra("crop", "true");
        // aspectX aspectY 是寬高的比例
        intent.putExtra("aspectX", 1);
        intent.putExtra("aspectY", 1);
        // outputX outputY 是裁剪圖片寬高
        intent.putExtra("outputX", 340);
        intent.putExtra("outputY", 340);
        //將URI指向相應的file:///…
        intent.putExtra(MediaStore.EXTRA_OUTPUT, uri);
        // 不返回圖片文件
        intent.putExtra("return-data", false);
        startActivityForResult(intent, RESULT_REQUEST_CODE);
    }

    //Android 4.4後通過Uri獲取路徑以及文件名一種方法
    public static String getRealPathFromURI(final Context context, final Uri uri ) {
        if ( null == uri ) return null;
        final String scheme = uri.getScheme();
        String data = null;
        if ( scheme == null )
            data = uri.getPath();
        else if ( ContentResolver.SCHEME_FILE.equals( scheme ) ) {
            data = uri.getPath();
        } else if ( ContentResolver.SCHEME_CONTENT.equals( scheme ) ) {
            Cursor cursor = context.getContentResolver().query( uri, new String[] { MediaStore.Images.ImageColumns.DATA }, null, null, null );
            if ( null != cursor ) {
                if ( cursor.moveToFirst() ) {
                    int index = cursor.getColumnIndex( MediaStore.Images.ImageColumns.DATA );
                    if ( index > -1 ) {
                        data = cursor.getString( index );
                    }
                }
                cursor.close();
            }
        }
        return data;
    }

    // 專爲Android4.4設計的從Uri獲取文件絕對路徑，以前的方法已不好使
    @SuppressLint("NewApi")
    public static String getPathByUri4kitkat(final Context context, final Uri uri) {
        final boolean isKitKat = Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT;
        // DocumentProvider
        if (isKitKat && DocumentsContract.isDocumentUri(context, uri)) {
            if (isExternalStorageDocument(uri)) {// ExternalStorageProvider
                final String docId = DocumentsContract.getDocumentId(uri);
                final String[] split = docId.split(":");
                final String type = split[0];
                if ("primary".equalsIgnoreCase(type)) {
                    return Environment.getExternalStorageDirectory() + "/" + split[1];
                }
            } else if (isDownloadsDocument(uri)) {// DownloadsProvider
                final String id = DocumentsContract.getDocumentId(uri);
                final Uri contentUri = ContentUris.withAppendedId(Uri.parse("content://downloads/public_downloads"),
                        Long.valueOf(id));
                return getDataColumn(context, contentUri, null, null);
            } else if (isMediaDocument(uri)) {// MediaProvider
                final String docId = DocumentsContract.getDocumentId(uri);
                final String[] split = docId.split(":");
                final String type = split[0];
                Uri contentUri = null;
                if ("image".equals(type)) {
                    contentUri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI;
                } else if ("video".equals(type)) {
                    contentUri = MediaStore.Video.Media.EXTERNAL_CONTENT_URI;
                } else if ("audio".equals(type)) {
                    contentUri = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
                }
                final String selection = "_id=?";
                final String[] selectionArgs = new String[] { split[1] };
                return getDataColumn(context, contentUri, selection, selectionArgs);
            }
        } else if ("content".equalsIgnoreCase(uri.getScheme())) {// MediaStore
            // (and
            // general)
            return getDataColumn(context, uri, null, null);
        } else if ("file".equalsIgnoreCase(uri.getScheme())) {// File
            return uri.getPath();
        }
        return null;
    }

    /**
     * Get the value of the data column for this Uri. This is useful for
     * MediaStore Uris, and other file-based ContentProviders.
     *
     * @param context
     *            The context.
     * @param uri
     *            The Uri to query.
     * @param selection
     *            (Optional) Filter used in the query.
     * @param selectionArgs
     *            (Optional) Selection arguments used in the query.
     * @return The value of the _data column, which is typically a file path.
     */
    public static String getDataColumn(Context context, Uri uri, String selection, String[] selectionArgs) {
        Cursor cursor = null;
        final String column = "_data";
        final String[] projection = { column };
        try {
            cursor = context.getContentResolver().query(uri, projection, selection, selectionArgs, null);
            if (cursor != null && cursor.moveToFirst()) {
                final int column_index = cursor.getColumnIndexOrThrow(column);
                return cursor.getString(column_index);
            }
        } finally {
            if (cursor != null)
                cursor.close();
        }
        return null;
    }

    /**
     * @param uri
     *            The Uri to check.
     * @return Whether the Uri authority is ExternalStorageProvider.
     */
    public static boolean isExternalStorageDocument(Uri uri) {
        return "com.android.externalstorage.documents".equals(uri.getAuthority());
    }

    /**
     * @param uri
     *            The Uri to check.
     * @return Whether the Uri authority is DownloadsProvider.
     */
    public static boolean isDownloadsDocument(Uri uri) {
        return "com.android.providers.downloads.documents".equals(uri.getAuthority());
    }

    /**
     * @param uri
     *            The Uri to check.
     * @return Whether the Uri authority is MediaProvider.
     */
    public static boolean isMediaDocument(Uri uri) {
        return "com.android.providers.media.documents".equals(uri.getAuthority());
    }

}