Refactor BaseKeyboardParser as Recursive Descendent Parser

Bug: 3082538
Change-Id: Ic0d72c6fe08cfc20db86aeffb10a27efe678095e
main
Tadashi G. Takaoka 2010-10-22 01:24:23 +09:00
parent d0ed8ec933
commit 0b1cb2d039
2 changed files with 293 additions and 126 deletions

View File

@ -121,7 +121,7 @@ public class BaseKeyboard {
/**
* Container for keys in the keyboard. All keys in a row are at the same Y-coordinate.
* Some of the key size defaults can be overridden per row from what the {@link Keyboard}
* Some of the key size defaults can be overridden per row from what the {@link BaseKeyboard}
* defines.
*/
public static class Row {
@ -135,7 +135,7 @@ public class BaseKeyboard {
public int verticalGap;
/**
* Edge flags for this row of keys. Possible values that can be assigned are
* {@link Keyboard#EDGE_TOP EDGE_TOP} and {@link Keyboard#EDGE_BOTTOM EDGE_BOTTOM}
* {@link BaseKeyboard#EDGE_TOP EDGE_TOP} and {@link BaseKeyboard#EDGE_BOTTOM EDGE_BOTTOM}
*/
public int rowEdgeFlags;
@ -217,8 +217,8 @@ public class BaseKeyboard {
/**
* Flags that specify the anchoring to edges of the keyboard for detecting touch events
* that are just out of the boundary of the key. This is a bit mask of
* {@link Keyboard#EDGE_LEFT}, {@link Keyboard#EDGE_RIGHT}, {@link Keyboard#EDGE_TOP} and
* {@link Keyboard#EDGE_BOTTOM}.
* {@link BaseKeyboard#EDGE_LEFT}, {@link BaseKeyboard#EDGE_RIGHT},
* {@link BaseKeyboard#EDGE_TOP} and {@link BaseKeyboard#EDGE_BOTTOM}.
*/
public int edgeFlags;
/** Whether this is a modifier key, such as Shift or Alt */
@ -274,7 +274,7 @@ public class BaseKeyboard {
* the XML parser.
* @param res resources associated with the caller's context
* @param parent the row that this key belongs to. The row must already be attached to
* a {@link Keyboard}.
* a {@link BaseKeyboard}.
* @param x the x coordinate of the top-left
* @param y the y coordinate of the top-left
* @param parser the XML parser containing the attributes for this key

View File

@ -24,13 +24,58 @@ import org.xmlpull.v1.XmlPullParserException;
import android.content.res.Resources;
import android.content.res.TypedArray;
import android.content.res.XmlResourceParser;
import android.util.Log;
import android.util.TypedValue;
import android.util.Xml;
import android.view.InflateException;
import java.io.IOException;
import java.util.List;
/**
* Parser for BaseKeyboard.
*
* This class parses Keyboard XML file and fill out keys in BaseKeyboard.
* The Keyboard XML file looks like:
* <pre>
* &gt;!-- xml/keyboard.xml --&lt;
* &gt;Keyboard keyboard_attributes*&lt;
* &gt;!-- Keyboard Content --&lt;
* &gt;Row row_attributes*&lt;
* &gt;!-- Row Content --&lt;
* &gt;Key key_attributes* /&lt;
* &gt;Spacer horizontalGap="0.2in" /&lt;
* &gt;include keyboardLayout="@xml/other_keys"&lt;
* ...
* &gt;/Row&lt;
* &gt;include keyboardLayout="@xml/other_rows"&lt;
* ...
* &gt;/Keyboard&lt;
* </pre>
* The xml file which is included in other file must have &gt;merge&lt; as root element, such as:
* <pre>
* &gt;!-- xml/other_keys.xml --&lt;
* &gt;merge&lt;
* &gt;Key key_attributes* /&lt;
* ...
* &gt;/merge&lt;
* </pre>
* and
* <pre>
* &gt;!-- xml/other_rows.xml --&lt;
* &gt;merge&lt;
* &gt;Row row_attributes*&lt;
* &gt;Key key_attributes* /&lt;
* &gt;/Row&lt;
* ...
* &gt;/merge&lt;
* </pre>
*/
public class BaseKeyboardParser {
private static final String TAG = "BaseKeyboardParser";
private static final boolean DEBUG_TAG = false;
private static final boolean DEBUG_PARSER = false;
// Keyboard XML Tags
private static final String TAG_KEYBOARD = "Keyboard";
private static final String TAG_ROW = "Row";
@ -63,71 +108,216 @@ public class BaseKeyboardParser {
public void parseKeyboard(XmlResourceParser parser)
throws XmlPullParserException, IOException {
final BaseKeyboard keyboard = mKeyboard;
Key key = null;
if (DEBUG_PARSER) debugEnterMethod("parseKeyboard", false);
int event;
while ((event = parser.next()) != XmlResourceParser.END_DOCUMENT) {
if (event == XmlResourceParser.START_TAG) {
final String tag = parser.getName();
if (DEBUG_TAG) debugStartTag("parseKeyboard", tag, false);
if (TAG_KEYBOARD.equals(tag)) {
parseKeyboardAttributes(parser);
parseKeyboardContent(parser, mKeyboard.getKeys());
break;
} else {
throw new IllegalStartTag(parser, TAG_KEYBOARD);
}
}
}
if (DEBUG_PARSER) debugLeaveMethod("parseKeyboard", false);
}
private void parseKeyboardAttributes(XmlResourceParser parser) {
final BaseKeyboard keyboard = mKeyboard;
final TypedArray a = mResources.obtainAttributes(Xml.asAttributeSet(parser),
R.styleable.BaseKeyboard);
final int width = keyboard.getKeyboardWidth();
final int height = keyboard.getKeyboardHeight();
keyboard.setKeyWidth(getDimensionOrFraction(a,
R.styleable.BaseKeyboard_keyWidth, width, width / 10));
keyboard.setKeyHeight(getDimensionOrFraction(a,
R.styleable.BaseKeyboard_keyHeight, height, 50));
keyboard.setHorizontalGap(getDimensionOrFraction(a,
R.styleable.BaseKeyboard_horizontalGap, width, 0));
keyboard.setVerticalGap(getDimensionOrFraction(a,
R.styleable.BaseKeyboard_verticalGap, height, 0));
a.recycle();
}
private void parseKeyboardContent(XmlResourceParser parser, final List<Key> keys)
throws XmlPullParserException, IOException {
if (DEBUG_PARSER) debugEnterMethod("parseKeyboardContent", keys == null);
int event;
while ((event = parser.next()) != XmlResourceParser.END_DOCUMENT) {
if (event == XmlResourceParser.START_TAG) {
final String tag = parser.getName();
if (DEBUG_TAG) debugStartTag("parseKeyboardContent", tag, keys == null);
if (TAG_ROW.equals(tag)) {
Row row = mKeyboard.createRowFromXml(mResources, parser);
if (keys != null && maybeStartRow(row)) {
parseRowContent(parser, row, keys);
} else {
// Skip entire <Row></Row>
parseRowContent(parser, row, null);
}
} else if (TAG_INCLUDE.equals(tag)) {
parseIncludeKeyboardContent(parser, keys);
} else {
throw new IllegalStartTag(parser, TAG_ROW);
}
} else if (event == XmlResourceParser.END_TAG) {
final String tag = parser.getName();
if (DEBUG_TAG) debugEndTag("parseKeyboardContent", tag, keys == null);
if (TAG_KEYBOARD.equals(tag)) {
endKeyboard(mKeyboard.getVerticalGap());
break;
} else if (TAG_MERGE.equals(tag)) {
break;
} else {
throw new IllegalEndTag(parser, TAG_ROW);
}
}
}
if (DEBUG_PARSER) debugLeaveMethod("parseKeyboardContent", keys == null);
}
private void parseRowContent(XmlResourceParser parser, Row row, List<Key> keys)
throws XmlPullParserException, IOException {
if (DEBUG_PARSER) debugEnterMethod("parseRowContent", keys == null);
int event;
while ((event = parser.next()) != XmlResourceParser.END_DOCUMENT) {
if (event == XmlResourceParser.START_TAG) {
final String tag = parser.getName();
if (DEBUG_TAG) debugStartTag("parseRowContent", tag, keys == null);
if (TAG_KEY.equals(tag)) {
parseKey(parser, row, keys);
} else if (TAG_SPACER.equals(tag)) {
parseSpacer(parser, keys);
} else if (TAG_INCLUDE.equals(tag)) {
parseIncludeRowContent(parser, row, keys);
} else {
throw new IllegalStartTag(parser, TAG_KEY);
}
} else if (event == XmlResourceParser.END_TAG) {
final String tag = parser.getName();
if (DEBUG_TAG) debugEndTag("parseRowContent", tag, keys == null);
if (TAG_ROW.equals(tag)) {
if (keys != null)
endRow();
break;
} else if (TAG_MERGE.equals(tag)) {
break;
} else {
throw new IllegalEndTag(parser, TAG_KEY);
}
}
}
if (DEBUG_PARSER) debugLeaveMethod("parseRowContent", keys == null);
}
private void parseKey(XmlResourceParser parser, Row row, List<Key> keys)
throws XmlPullParserException, IOException {
if (DEBUG_PARSER) debugEnterMethod("parseKey", keys == null);
if (keys == null) {
checkEndTag(TAG_KEY, parser);
} else {
Key key = mKeyboard.createKeyFromXml(mResources, row, mCurrentX, mCurrentY, parser);
checkEndTag(TAG_KEY, parser);
keys.add(key);
if (key.codes[0] == BaseKeyboard.KEYCODE_SHIFT)
mKeyboard.getShiftKeys().add(key);
endKey(key);
}
}
private void parseSpacer(XmlResourceParser parser, List<Key> keys)
throws XmlPullParserException, IOException {
if (DEBUG_PARSER) debugEnterMethod("parseSpacer", keys == null);
if (keys == null) {
checkEndTag(TAG_SPACER, parser);
} else {
final TypedArray a = mResources.obtainAttributes(Xml.asAttributeSet(parser),
R.styleable.BaseKeyboard);
int gap = getDimensionOrFraction(a, R.styleable.BaseKeyboard_horizontalGap,
mKeyboard.getKeyboardWidth(), 0);
a.recycle();
checkEndTag(TAG_SPACER, parser);
setSpacer(gap);
}
}
private void parseIncludeKeyboardContent(XmlResourceParser parser, List<Key> keys)
throws XmlPullParserException, IOException {
parseIncludeInternal(parser, null, keys);
}
private void parseIncludeRowContent(XmlResourceParser parser, Row row, List<Key> keys)
throws XmlPullParserException, IOException {
parseIncludeInternal(parser, row, keys);
}
private void parseIncludeInternal(XmlResourceParser parser, Row row, List<Key> keys)
throws XmlPullParserException, IOException {
if (DEBUG_PARSER) debugEnterMethod("parseInclude", keys == null);
if (keys == null) {
checkEndTag(TAG_INCLUDE, parser);
} else {
final TypedArray a = mResources.obtainAttributes(Xml.asAttributeSet(parser),
R.styleable.BaseKeyboard_Include);
final int keyboardLayout = a.getResourceId(
R.styleable.BaseKeyboard_Include_keyboardLayout, 0);
a.recycle();
checkEndTag(TAG_INCLUDE, parser);
if (keyboardLayout == 0)
throw new ParseException("No keyboardLayout attribute in <include/>", parser);
parseMerge(mResources.getLayout(keyboardLayout), row, keys);
}
if (DEBUG_PARSER) debugLeaveMethod("parseInclude", keys == null);
}
private void parseMerge(XmlResourceParser parser, Row row, List<Key> keys)
throws XmlPullParserException, IOException {
if (DEBUG_PARSER) debugEnterMethod("parseMerge", keys == null);
int event;
while ((event = parser.next()) != XmlResourceParser.END_DOCUMENT) {
if (event == XmlResourceParser.START_TAG) {
String tag = parser.getName();
if (TAG_ROW.equals(tag)) {
// TODO createRowFromXml should not be called from
// BaseKeyboard constructor.
Row row = keyboard.createRowFromXml(mResources, parser);
if (!startRow(row))
skipToEndOfRow(parser);
} else if (TAG_KEY.equals(tag)) {
// TODO createKeyFromXml should not be called from
// BaseKeyboard constructor.
key = keyboard.createKeyFromXml(mResources, mCurrentRow, mCurrentX, mCurrentY,
parser);
keyboard.getKeys().add(key);
if (key.codes[0] == BaseKeyboard.KEYCODE_SHIFT)
keyboard.getShiftKeys().add(key);
} else if (TAG_SPACER.equals(tag)) {
parseSpacerAttribute(parser);
} else if (TAG_KEYBOARD.equals(tag)) {
parseKeyboardAttributes(parser);
} else if (TAG_INCLUDE.equals(tag)) {
if (parser.getDepth() == 0)
throw new InflateException("<include /> cannot be the root element");
parseInclude(parser);
} else if (TAG_MERGE.equals(tag)) {
throw new InflateException(
"<merge> must not be appeared in keyboard XML file");
if (DEBUG_TAG) debugStartTag("parseMerge", tag, keys == null);
if (TAG_MERGE.equals(tag)) {
if (row == null) {
parseKeyboardContent(parser, keys);
} else {
parseRowContent(parser, row, keys);
}
break;
} else {
throw new InflateException("unknown start tag: " + tag);
}
} else if (event == XmlResourceParser.END_TAG) {
String tag = parser.getName();
if (TAG_KEY.equals(tag)) {
endKey(key);
} else if (TAG_ROW.equals(tag)) {
endRow();
} else if (TAG_SPACER.equals(tag)) {
;
} else if (TAG_KEYBOARD.equals(tag)) {
endKeyboard(mKeyboard.getVerticalGap());
} else if (TAG_INCLUDE.equals(tag)) {
;
} else if (TAG_MERGE.equals(tag)) {
return;
} else {
throw new InflateException("unknown end tag: " + tag);
throw new ParseException(
"Included keyboard layout must have <merge> root element", parser);
}
}
}
if (DEBUG_PARSER) debugLeaveMethod("parseMerge", keys == null);
}
private static void checkEndTag(String tag, XmlResourceParser parser)
throws XmlPullParserException, IOException {
if (parser.next() == XmlResourceParser.END_TAG && tag.equals(parser.getName()))
return;
throw new NonEmptyTag(tag, parser);
}
// return true if the row is valid for this keyboard mode
private boolean startRow(Row row) {
mCurrentX = 0;
mCurrentRow = row;
return row.mode == 0 || row.mode == mKeyboard.getKeyboardMode();
}
private void skipRow() {
mCurrentRow = null;
private boolean maybeStartRow(Row row) {
if (DEBUG_TAG)
Log.d(TAG, String.format("startRow: mode=0x%08x keyboardMode=0x%08x",
row.mode, mKeyboard.getKeyboardMode()));
if (row.mode == 0 || row.mode == mKeyboard.getKeyboardMode()) {
mCurrentX = 0;
mCurrentRow = row;
return true;
} else {
return false;
}
}
private void endRow() {
@ -151,73 +341,6 @@ public class BaseKeyboardParser {
mCurrentX += gap;
}
private void parseSpacerAttribute(XmlResourceParser parser) {
final TypedArray a = mResources.obtainAttributes(Xml.asAttributeSet(parser),
R.styleable.BaseKeyboard);
int gap = getDimensionOrFraction(a, R.styleable.BaseKeyboard_horizontalGap,
mKeyboard.getKeyboardWidth(), 0);
a.recycle();
setSpacer(gap);
}
private void parseInclude(XmlResourceParser parent)
throws XmlPullParserException, IOException {
final TypedArray a = mResources.obtainAttributes(Xml.asAttributeSet(parent),
R.styleable.BaseKeyboard_Include);
final int keyboardLayout = a.getResourceId(
R.styleable.BaseKeyboard_Include_keyboardLayout, 0);
a.recycle();
if (keyboardLayout == 0)
throw new InflateException("<include /> must have keyboardLayout attribute");
final XmlResourceParser parser = mResources.getLayout(keyboardLayout);
int event;
while ((event = parser.next()) != XmlResourceParser.END_DOCUMENT) {
if (event == XmlResourceParser.START_TAG) {
String name = parser.getName();
if (TAG_MERGE.equals(name)) {
parseKeyboard(parser);
return;
} else {
throw new InflateException(
"include keyboard layout must have <merge> root element");
}
}
}
}
private void skipToEndOfRow(XmlResourceParser parser)
throws XmlPullParserException, IOException {
int event;
while ((event = parser.next()) != XmlResourceParser.END_DOCUMENT) {
if (event == XmlResourceParser.END_TAG) {
String tag = parser.getName();
if (TAG_ROW.equals(tag)) {
skipRow();
return;
}
}
}
throw new InflateException("can not find </Row>");
}
private void parseKeyboardAttributes(XmlResourceParser parser) {
final BaseKeyboard keyboard = mKeyboard;
final TypedArray a = mResources.obtainAttributes(Xml.asAttributeSet(parser),
R.styleable.BaseKeyboard);
final int width = keyboard.getKeyboardWidth();
final int height = keyboard.getKeyboardHeight();
keyboard.setKeyWidth(getDimensionOrFraction(a,
R.styleable.BaseKeyboard_keyWidth, width, width / 10));
keyboard.setKeyHeight(getDimensionOrFraction(a,
R.styleable.BaseKeyboard_keyHeight, height, 50));
keyboard.setHorizontalGap(getDimensionOrFraction(a,
R.styleable.BaseKeyboard_horizontalGap, width, 0));
keyboard.setVerticalGap(getDimensionOrFraction(a,
R.styleable.BaseKeyboard_verticalGap, height, 0));
a.recycle();
}
public static int getDimensionOrFraction(TypedArray a, int index, int base, int defValue) {
final TypedValue value = a.peekValue(index);
if (value == null)
@ -230,4 +353,48 @@ public class BaseKeyboardParser {
}
return defValue;
}
}
@SuppressWarnings("serial")
private static class ParseException extends InflateException {
public ParseException(String msg, XmlResourceParser parser) {
super(msg + " at line " + parser.getLineNumber());
}
}
@SuppressWarnings("serial")
private static class IllegalStartTag extends ParseException {
public IllegalStartTag(XmlResourceParser parser, String parent) {
super("Illegal start tag " + parser.getName() + " in " + parent, parser);
}
}
@SuppressWarnings("serial")
private static class IllegalEndTag extends ParseException {
public IllegalEndTag(XmlResourceParser parser, String parent) {
super("Illegal end tag " + parser.getName() + " in " + parent, parser);
}
}
@SuppressWarnings("serial")
private static class NonEmptyTag extends ParseException {
public NonEmptyTag(String tag, XmlResourceParser parser) {
super(tag + " must be empty tag", parser);
}
}
private static void debugEnterMethod(String title, boolean skip) {
Log.d(TAG, title + ": enter" + (skip ? " skip" : ""));
}
private static void debugLeaveMethod(String title, boolean skip) {
Log.d(TAG, title + ": leave" + (skip ? " skip" : ""));
}
private static void debugStartTag(String title, String tag, boolean skip) {
Log.d(TAG, title + ": <" + tag + ">" + (skip ? " skip" : ""));
}
private static void debugEndTag(String title, String tag, boolean skip) {
Log.d(TAG, title + ": </" + tag + ">" + (skip ? " skip" : ""));
}
}