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A library jar that provides APIs for Applications written for the Google Android Platform.
/*
* Copyright (C) 2010 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package android.text.method;
import android.text.Layout;
import android.text.Spannable;
import android.view.InputDevice;
import android.view.KeyEvent;
import android.view.MotionEvent;
import android.widget.TextView;
/**
* Base classes for movement methods.
*/
public class BaseMovementMethod implements MovementMethod {
@Override
public boolean canSelectArbitrarily() {
return false;
}
@Override
public void initialize(TextView widget, Spannable text) {
}
@Override
public boolean onKeyDown(TextView widget, Spannable text, int keyCode, KeyEvent event) {
final int movementMetaState = getMovementMetaState(text, event);
boolean handled = handleMovementKey(widget, text, keyCode, movementMetaState, event);
if (handled) {
MetaKeyKeyListener.adjustMetaAfterKeypress(text);
MetaKeyKeyListener.resetLockedMeta(text);
}
return handled;
}
@Override
public boolean onKeyOther(TextView widget, Spannable text, KeyEvent event) {
final int movementMetaState = getMovementMetaState(text, event);
final int keyCode = event.getKeyCode();
if (keyCode != KeyEvent.KEYCODE_UNKNOWN
&& event.getAction() == KeyEvent.ACTION_MULTIPLE) {
final int repeat = event.getRepeatCount();
boolean handled = false;
for (int i = 0; i < repeat; i++) {
if (!handleMovementKey(widget, text, keyCode, movementMetaState, event)) {
break;
}
handled = true;
}
if (handled) {
MetaKeyKeyListener.adjustMetaAfterKeypress(text);
MetaKeyKeyListener.resetLockedMeta(text);
}
return handled;
}
return false;
}
@Override
public boolean onKeyUp(TextView widget, Spannable text, int keyCode, KeyEvent event) {
return false;
}
@Override
public void onTakeFocus(TextView widget, Spannable text, int direction) {
}
@Override
public boolean onTouchEvent(TextView widget, Spannable text, MotionEvent event) {
return false;
}
@Override
public boolean onTrackballEvent(TextView widget, Spannable text, MotionEvent event) {
return false;
}
@Override
public boolean onGenericMotionEvent(TextView widget, Spannable text, MotionEvent event) {
if ((event.getSource() & InputDevice.SOURCE_CLASS_POINTER) != 0) {
switch (event.getAction()) {
case MotionEvent.ACTION_SCROLL: {
final float vscroll;
final float hscroll;
if ((event.getMetaState() & KeyEvent.META_SHIFT_ON) != 0) {
vscroll = 0;
hscroll = event.getAxisValue(MotionEvent.AXIS_VSCROLL);
} else {
vscroll = -event.getAxisValue(MotionEvent.AXIS_VSCROLL);
hscroll = event.getAxisValue(MotionEvent.AXIS_HSCROLL);
}
boolean handled = false;
if (hscroll < 0) {
handled |= scrollLeft(widget, text, (int)Math.ceil(-hscroll));
} else if (hscroll > 0) {
handled |= scrollRight(widget, text, (int)Math.ceil(hscroll));
}
if (vscroll < 0) {
handled |= scrollUp(widget, text, (int)Math.ceil(-vscroll));
} else if (vscroll > 0) {
handled |= scrollDown(widget, text, (int)Math.ceil(vscroll));
}
return handled;
}
}
}
return false;
}
/**
* Gets the meta state used for movement using the modifiers tracked by the text
* buffer as well as those present in the key event.
*
* The movement meta state excludes the state of locked modifiers or the SHIFT key
* since they are not used by movement actions (but they may be used for selection).
*
* @param buffer The text buffer.
* @param event The key event.
* @return The keyboard meta states used for movement.
*/
protected int getMovementMetaState(Spannable buffer, KeyEvent event) {
// We ignore locked modifiers and SHIFT.
int metaState = MetaKeyKeyListener.getMetaState(buffer, event)
& ~(MetaKeyKeyListener.META_ALT_LOCKED | MetaKeyKeyListener.META_SYM_LOCKED);
return KeyEvent.normalizeMetaState(metaState) & ~KeyEvent.META_SHIFT_MASK;
}
/**
* Performs a movement key action.
* The default implementation decodes the key down and invokes movement actions
* such as {@link #down} and {@link #up}.
* {@link #onKeyDown(TextView, Spannable, int, KeyEvent)} calls this method once
* to handle an {@link KeyEvent#ACTION_DOWN}.
* {@link #onKeyOther(TextView, Spannable, KeyEvent)} calls this method repeatedly
* to handle each repetition of an {@link KeyEvent#ACTION_MULTIPLE}.
*
* @param widget The text view.
* @param buffer The text buffer.
* @param event The key event.
* @param keyCode The key code.
* @param movementMetaState The keyboard meta states used for movement.
* @param event The key event.
* @return True if the event was handled.
*/
protected boolean handleMovementKey(TextView widget, Spannable buffer,
int keyCode, int movementMetaState, KeyEvent event) {
switch (keyCode) {
case KeyEvent.KEYCODE_DPAD_LEFT:
if (KeyEvent.metaStateHasNoModifiers(movementMetaState)) {
return left(widget, buffer);
} else if (KeyEvent.metaStateHasModifiers(movementMetaState,
KeyEvent.META_CTRL_ON)) {
return leftWord(widget, buffer);
} else if (KeyEvent.metaStateHasModifiers(movementMetaState,
KeyEvent.META_ALT_ON)) {
return lineStart(widget, buffer);
}
break;
case KeyEvent.KEYCODE_DPAD_RIGHT:
if (KeyEvent.metaStateHasNoModifiers(movementMetaState)) {
return right(widget, buffer);
} else if (KeyEvent.metaStateHasModifiers(movementMetaState,
KeyEvent.META_CTRL_ON)) {
return rightWord(widget, buffer);
} else if (KeyEvent.metaStateHasModifiers(movementMetaState,
KeyEvent.META_ALT_ON)) {
return lineEnd(widget, buffer);
}
break;
case KeyEvent.KEYCODE_DPAD_UP:
if (KeyEvent.metaStateHasNoModifiers(movementMetaState)) {
return up(widget, buffer);
} else if (KeyEvent.metaStateHasModifiers(movementMetaState,
KeyEvent.META_ALT_ON)) {
return top(widget, buffer);
}
break;
case KeyEvent.KEYCODE_DPAD_DOWN:
if (KeyEvent.metaStateHasNoModifiers(movementMetaState)) {
return down(widget, buffer);
} else if (KeyEvent.metaStateHasModifiers(movementMetaState,
KeyEvent.META_ALT_ON)) {
return bottom(widget, buffer);
}
break;
case KeyEvent.KEYCODE_PAGE_UP:
if (KeyEvent.metaStateHasNoModifiers(movementMetaState)) {
return pageUp(widget, buffer);
} else if (KeyEvent.metaStateHasModifiers(movementMetaState,
KeyEvent.META_ALT_ON)) {
return top(widget, buffer);
}
break;
case KeyEvent.KEYCODE_PAGE_DOWN:
if (KeyEvent.metaStateHasNoModifiers(movementMetaState)) {
return pageDown(widget, buffer);
} else if (KeyEvent.metaStateHasModifiers(movementMetaState,
KeyEvent.META_ALT_ON)) {
return bottom(widget, buffer);
}
break;
case KeyEvent.KEYCODE_MOVE_HOME:
if (KeyEvent.metaStateHasNoModifiers(movementMetaState)) {
return home(widget, buffer);
} else if (KeyEvent.metaStateHasModifiers(movementMetaState,
KeyEvent.META_CTRL_ON)) {
return top(widget, buffer);
}
break;
case KeyEvent.KEYCODE_MOVE_END:
if (KeyEvent.metaStateHasNoModifiers(movementMetaState)) {
return end(widget, buffer);
} else if (KeyEvent.metaStateHasModifiers(movementMetaState,
KeyEvent.META_CTRL_ON)) {
return bottom(widget, buffer);
}
break;
}
return false;
}
/**
* Performs a left movement action.
* Moves the cursor or scrolls left by one character.
*
* @param widget The text view.
* @param buffer The text buffer.
* @return True if the event was handled.
*/
protected boolean left(TextView widget, Spannable buffer) {
return false;
}
/**
* Performs a right movement action.
* Moves the cursor or scrolls right by one character.
*
* @param widget The text view.
* @param buffer The text buffer.
* @return True if the event was handled.
*/
protected boolean right(TextView widget, Spannable buffer) {
return false;
}
/**
* Performs an up movement action.
* Moves the cursor or scrolls up by one line.
*
* @param widget The text view.
* @param buffer The text buffer.
* @return True if the event was handled.
*/
protected boolean up(TextView widget, Spannable buffer) {
return false;
}
/**
* Performs a down movement action.
* Moves the cursor or scrolls down by one line.
*
* @param widget The text view.
* @param buffer The text buffer.
* @return True if the event was handled.
*/
protected boolean down(TextView widget, Spannable buffer) {
return false;
}
/**
* Performs a page-up movement action.
* Moves the cursor or scrolls up by one page.
*
* @param widget The text view.
* @param buffer The text buffer.
* @return True if the event was handled.
*/
protected boolean pageUp(TextView widget, Spannable buffer) {
return false;
}
/**
* Performs a page-down movement action.
* Moves the cursor or scrolls down by one page.
*
* @param widget The text view.
* @param buffer The text buffer.
* @return True if the event was handled.
*/
protected boolean pageDown(TextView widget, Spannable buffer) {
return false;
}
/**
* Performs a top movement action.
* Moves the cursor or scrolls to the top of the buffer.
*
* @param widget The text view.
* @param buffer The text buffer.
* @return True if the event was handled.
*/
protected boolean top(TextView widget, Spannable buffer) {
return false;
}
/**
* Performs a bottom movement action.
* Moves the cursor or scrolls to the bottom of the buffer.
*
* @param widget The text view.
* @param buffer The text buffer.
* @return True if the event was handled.
*/
protected boolean bottom(TextView widget, Spannable buffer) {
return false;
}
/**
* Performs a line-start movement action.
* Moves the cursor or scrolls to the start of the line.
*
* @param widget The text view.
* @param buffer The text buffer.
* @return True if the event was handled.
*/
protected boolean lineStart(TextView widget, Spannable buffer) {
return false;
}
/**
* Performs a line-end movement action.
* Moves the cursor or scrolls to the end of the line.
*
* @param widget The text view.
* @param buffer The text buffer.
* @return True if the event was handled.
*/
protected boolean lineEnd(TextView widget, Spannable buffer) {
return false;
}
/** {@hide} */
protected boolean leftWord(TextView widget, Spannable buffer) {
return false;
}
/** {@hide} */
protected boolean rightWord(TextView widget, Spannable buffer) {
return false;
}
/**
* Performs a home movement action.
* Moves the cursor or scrolls to the start of the line or to the top of the
* document depending on whether the insertion point is being moved or
* the document is being scrolled.
*
* @param widget The text view.
* @param buffer The text buffer.
* @return True if the event was handled.
*/
protected boolean home(TextView widget, Spannable buffer) {
return false;
}
/**
* Performs an end movement action.
* Moves the cursor or scrolls to the start of the line or to the top of the
* document depending on whether the insertion point is being moved or
* the document is being scrolled.
*
* @param widget The text view.
* @param buffer The text buffer.
* @return True if the event was handled.
*/
protected boolean end(TextView widget, Spannable buffer) {
return false;
}
private int getTopLine(TextView widget) {
return widget.getLayout().getLineForVertical(widget.getScrollY());
}
private int getBottomLine(TextView widget) {
return widget.getLayout().getLineForVertical(widget.getScrollY() + getInnerHeight(widget));
}
private int getInnerWidth(TextView widget) {
return widget.getWidth() - widget.getTotalPaddingLeft() - widget.getTotalPaddingRight();
}
private int getInnerHeight(TextView widget) {
return widget.getHeight() - widget.getTotalPaddingTop() - widget.getTotalPaddingBottom();
}
private int getCharacterWidth(TextView widget) {
return (int) Math.ceil(widget.getPaint().getFontSpacing());
}
private int getScrollBoundsLeft(TextView widget) {
final Layout layout = widget.getLayout();
final int topLine = getTopLine(widget);
final int bottomLine = getBottomLine(widget);
if (topLine > bottomLine) {
return 0;
}
int left = Integer.MAX_VALUE;
for (int line = topLine; line <= bottomLine; line++) {
final int lineLeft = (int) Math.floor(layout.getLineLeft(line));
if (lineLeft < left) {
left = lineLeft;
}
}
return left;
}
private int getScrollBoundsRight(TextView widget) {
final Layout layout = widget.getLayout();
final int topLine = getTopLine(widget);
final int bottomLine = getBottomLine(widget);
if (topLine > bottomLine) {
return 0;
}
int right = Integer.MIN_VALUE;
for (int line = topLine; line <= bottomLine; line++) {
final int lineRight = (int) Math.ceil(layout.getLineRight(line));
if (lineRight > right) {
right = lineRight;
}
}
return right;
}
/**
* Performs a scroll left action.
* Scrolls left by the specified number of characters.
*
* @param widget The text view.
* @param buffer The text buffer.
* @param amount The number of characters to scroll by. Must be at least 1.
* @return True if the event was handled.
* @hide
*/
protected boolean scrollLeft(TextView widget, Spannable buffer, int amount) {
final int minScrollX = getScrollBoundsLeft(widget);
int scrollX = widget.getScrollX();
if (scrollX > minScrollX) {
scrollX = Math.max(scrollX - getCharacterWidth(widget) * amount, minScrollX);
widget.scrollTo(scrollX, widget.getScrollY());
return true;
}
return false;
}
/**
* Performs a scroll right action.
* Scrolls right by the specified number of characters.
*
* @param widget The text view.
* @param buffer The text buffer.
* @param amount The number of characters to scroll by. Must be at least 1.
* @return True if the event was handled.
* @hide
*/
protected boolean scrollRight(TextView widget, Spannable buffer, int amount) {
final int maxScrollX = getScrollBoundsRight(widget) - getInnerWidth(widget);
int scrollX = widget.getScrollX();
if (scrollX < maxScrollX) {
scrollX = Math.min(scrollX + getCharacterWidth(widget) * amount, maxScrollX);
widget.scrollTo(scrollX, widget.getScrollY());
return true;
}
return false;
}
/**
* Performs a scroll up action.
* Scrolls up by the specified number of lines.
*
* @param widget The text view.
* @param buffer The text buffer.
* @param amount The number of lines to scroll by. Must be at least 1.
* @return True if the event was handled.
* @hide
*/
protected boolean scrollUp(TextView widget, Spannable buffer, int amount) {
final Layout layout = widget.getLayout();
final int top = widget.getScrollY();
int topLine = layout.getLineForVertical(top);
if (layout.getLineTop(topLine) == top) {
// If the top line is partially visible, bring it all the way
// into view; otherwise, bring the previous line into view.
topLine -= 1;
}
if (topLine >= 0) {
topLine = Math.max(topLine - amount + 1, 0);
Touch.scrollTo(widget, layout, widget.getScrollX(), layout.getLineTop(topLine));
return true;
}
return false;
}
/**
* Performs a scroll down action.
* Scrolls down by the specified number of lines.
*
* @param widget The text view.
* @param buffer The text buffer.
* @param amount The number of lines to scroll by. Must be at least 1.
* @return True if the event was handled.
* @hide
*/
protected boolean scrollDown(TextView widget, Spannable buffer, int amount) {
final Layout layout = widget.getLayout();
final int innerHeight = getInnerHeight(widget);
final int bottom = widget.getScrollY() + innerHeight;
int bottomLine = layout.getLineForVertical(bottom);
if (layout.getLineTop(bottomLine + 1) < bottom + 1) {
// Less than a pixel of this line is out of view,
// so we must have tried to make it entirely in view
// and now want the next line to be in view instead.
bottomLine += 1;
}
final int limit = layout.getLineCount() - 1;
if (bottomLine <= limit) {
bottomLine = Math.min(bottomLine + amount - 1, limit);
Touch.scrollTo(widget, layout, widget.getScrollX(),
layout.getLineTop(bottomLine + 1) - innerHeight);
return true;
}
return false;
}
/**
* Performs a scroll page up action.
* Scrolls up by one page.
*
* @param widget The text view.
* @param buffer The text buffer.
* @return True if the event was handled.
* @hide
*/
protected boolean scrollPageUp(TextView widget, Spannable buffer) {
final Layout layout = widget.getLayout();
final int top = widget.getScrollY() - getInnerHeight(widget);
int topLine = layout.getLineForVertical(top);
if (topLine >= 0) {
Touch.scrollTo(widget, layout, widget.getScrollX(), layout.getLineTop(topLine));
return true;
}
return false;
}
/**
* Performs a scroll page up action.
* Scrolls down by one page.
*
* @param widget The text view.
* @param buffer The text buffer.
* @return True if the event was handled.
* @hide
*/
protected boolean scrollPageDown(TextView widget, Spannable buffer) {
final Layout layout = widget.getLayout();
final int innerHeight = getInnerHeight(widget);
final int bottom = widget.getScrollY() + innerHeight + innerHeight;
int bottomLine = layout.getLineForVertical(bottom);
if (bottomLine <= layout.getLineCount() - 1) {
Touch.scrollTo(widget, layout, widget.getScrollX(),
layout.getLineTop(bottomLine + 1) - innerHeight);
return true;
}
return false;
}
/**
* Performs a scroll to top action.
* Scrolls to the top of the document.
*
* @param widget The text view.
* @param buffer The text buffer.
* @return True if the event was handled.
* @hide
*/
protected boolean scrollTop(TextView widget, Spannable buffer) {
final Layout layout = widget.getLayout();
if (getTopLine(widget) >= 0) {
Touch.scrollTo(widget, layout, widget.getScrollX(), layout.getLineTop(0));
return true;
}
return false;
}
/**
* Performs a scroll to bottom action.
* Scrolls to the bottom of the document.
*
* @param widget The text view.
* @param buffer The text buffer.
* @return True if the event was handled.
* @hide
*/
protected boolean scrollBottom(TextView widget, Spannable buffer) {
final Layout layout = widget.getLayout();
final int lineCount = layout.getLineCount();
if (getBottomLine(widget) <= lineCount - 1) {
Touch.scrollTo(widget, layout, widget.getScrollX(),
layout.getLineTop(lineCount) - getInnerHeight(widget));
return true;
}
return false;
}
/**
* Performs a scroll to line start action.
* Scrolls to the start of the line.
*
* @param widget The text view.
* @param buffer The text buffer.
* @return True if the event was handled.
* @hide
*/
protected boolean scrollLineStart(TextView widget, Spannable buffer) {
final int minScrollX = getScrollBoundsLeft(widget);
int scrollX = widget.getScrollX();
if (scrollX > minScrollX) {
widget.scrollTo(minScrollX, widget.getScrollY());
return true;
}
return false;
}
/**
* Performs a scroll to line end action.
* Scrolls to the end of the line.
*
* @param widget The text view.
* @param buffer The text buffer.
* @return True if the event was handled.
* @hide
*/
protected boolean scrollLineEnd(TextView widget, Spannable buffer) {
final int maxScrollX = getScrollBoundsRight(widget) - getInnerWidth(widget);
int scrollX = widget.getScrollX();
if (scrollX < maxScrollX) {
widget.scrollTo(maxScrollX, widget.getScrollY());
return true;
}
return false;
}
}