shaka-packager/base/i18n/bidi_line_iterator.h

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1.4 KiB
C++

// Copyright (c) 2011 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef BASE_I18N_BIDI_LINE_ITERATOR_H_
#define BASE_I18N_BIDI_LINE_ITERATOR_H_
#include "base/basictypes.h"
#include "base/i18n/base_i18n_export.h"
#include "base/strings/string16.h"
#include "third_party/icu/source/common/unicode/ubidi.h"
namespace base {
namespace i18n {
// A simple wrapper class for the bidirectional iterator of ICU.
// This class uses the bidirectional iterator of ICU to split a line of
// bidirectional texts into visual runs in its display order.
class BASE_I18N_EXPORT BiDiLineIterator {
public:
BiDiLineIterator();
~BiDiLineIterator();
// Initializes the bidirectional iterator with the specified text. Returns
// whether initialization succeeded.
bool Open(const string16& text, bool right_to_left, bool url);
// Returns the number of visual runs in the text, or zero on error.
int CountRuns();
// Gets the logical offset, length, and direction of the specified visual run.
UBiDiDirection GetVisualRun(int index, int* start, int* length);
// Given a start position, figure out where the run ends (and the BiDiLevel).
void GetLogicalRun(int start, int* end, UBiDiLevel* level);
private:
UBiDi* bidi_;
DISALLOW_COPY_AND_ASSIGN(BiDiLineIterator);
};
} // namespace i18n
} // namespace base
#endif // BASE_I18N_BIDI_LINE_ITERATOR_H_