| /* |
| * Copyright (C) 2006 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.annotation.NonNull; |
| import android.graphics.Rect; |
| import android.text.Layout; |
| import android.text.Selection; |
| import android.text.Spannable; |
| import android.view.KeyEvent; |
| import android.view.MotionEvent; |
| import android.view.View; |
| import android.widget.TextView; |
| |
| /** |
| * A movement method that provides cursor movement and selection. |
| * Supports displaying the context menu on DPad Center. |
| */ |
| public class ArrowKeyMovementMethod extends BaseMovementMethod implements MovementMethod { |
| private static boolean isSelecting(Spannable buffer) { |
| return ((MetaKeyKeyListener.getMetaState(buffer, MetaKeyKeyListener.META_SHIFT_ON) == 1) || |
| (MetaKeyKeyListener.getMetaState(buffer, MetaKeyKeyListener.META_SELECTING) != 0)); |
| } |
| |
| private static int getCurrentLineTop(Spannable buffer, Layout layout) { |
| return layout.getLineTop(layout.getLineForOffset(Selection.getSelectionEnd(buffer))); |
| } |
| |
| private static int getPageHeight(TextView widget) { |
| // This calculation does not take into account the view transformations that |
| // may have been applied to the child or its containers. In case of scaling or |
| // rotation, the calculated page height may be incorrect. |
| final Rect rect = new Rect(); |
| return widget.getGlobalVisibleRect(rect) ? rect.height() : 0; |
| } |
| |
| @Override |
| protected boolean handleMovementKey(TextView widget, Spannable buffer, int keyCode, |
| int movementMetaState, KeyEvent event) { |
| switch (keyCode) { |
| case KeyEvent.KEYCODE_DPAD_CENTER: |
| if (KeyEvent.metaStateHasNoModifiers(movementMetaState)) { |
| if (event.getAction() == KeyEvent.ACTION_DOWN |
| && event.getRepeatCount() == 0 |
| && MetaKeyKeyListener.getMetaState(buffer, |
| MetaKeyKeyListener.META_SELECTING, event) != 0) { |
| return widget.showContextMenu(); |
| } |
| } |
| break; |
| } |
| return super.handleMovementKey(widget, buffer, keyCode, movementMetaState, event); |
| } |
| |
| @Override |
| protected boolean left(TextView widget, Spannable buffer) { |
| if (widget.isOffsetMappingAvailable()) { |
| return false; |
| } |
| final Layout layout = widget.getLayout(); |
| if (isSelecting(buffer)) { |
| return Selection.extendLeft(buffer, layout); |
| } else { |
| return Selection.moveLeft(buffer, layout); |
| } |
| } |
| |
| @Override |
| protected boolean right(TextView widget, Spannable buffer) { |
| if (widget.isOffsetMappingAvailable()) { |
| return false; |
| } |
| final Layout layout = widget.getLayout(); |
| if (isSelecting(buffer)) { |
| return Selection.extendRight(buffer, layout); |
| } else { |
| return Selection.moveRight(buffer, layout); |
| } |
| } |
| |
| @Override |
| protected boolean up(TextView widget, Spannable buffer) { |
| if (widget.isOffsetMappingAvailable()) { |
| return false; |
| } |
| final Layout layout = widget.getLayout(); |
| if (isSelecting(buffer)) { |
| return Selection.extendUp(buffer, layout); |
| } else { |
| return Selection.moveUp(buffer, layout); |
| } |
| } |
| |
| @Override |
| protected boolean down(TextView widget, Spannable buffer) { |
| if (widget.isOffsetMappingAvailable()) { |
| return false; |
| } |
| final Layout layout = widget.getLayout(); |
| if (isSelecting(buffer)) { |
| return Selection.extendDown(buffer, layout); |
| } else { |
| return Selection.moveDown(buffer, layout); |
| } |
| } |
| |
| @Override |
| protected boolean pageUp(TextView widget, Spannable buffer) { |
| if (widget.isOffsetMappingAvailable()) { |
| return false; |
| } |
| final Layout layout = widget.getLayout(); |
| final boolean selecting = isSelecting(buffer); |
| final int targetY = getCurrentLineTop(buffer, layout) - getPageHeight(widget); |
| boolean handled = false; |
| for (;;) { |
| final int previousSelectionEnd = Selection.getSelectionEnd(buffer); |
| if (selecting) { |
| Selection.extendUp(buffer, layout); |
| } else { |
| Selection.moveUp(buffer, layout); |
| } |
| if (Selection.getSelectionEnd(buffer) == previousSelectionEnd) { |
| break; |
| } |
| handled = true; |
| if (getCurrentLineTop(buffer, layout) <= targetY) { |
| break; |
| } |
| } |
| return handled; |
| } |
| |
| @Override |
| protected boolean pageDown(TextView widget, Spannable buffer) { |
| if (widget.isOffsetMappingAvailable()) { |
| return false; |
| } |
| final Layout layout = widget.getLayout(); |
| final boolean selecting = isSelecting(buffer); |
| final int targetY = getCurrentLineTop(buffer, layout) + getPageHeight(widget); |
| boolean handled = false; |
| for (;;) { |
| final int previousSelectionEnd = Selection.getSelectionEnd(buffer); |
| if (selecting) { |
| Selection.extendDown(buffer, layout); |
| } else { |
| Selection.moveDown(buffer, layout); |
| } |
| if (Selection.getSelectionEnd(buffer) == previousSelectionEnd) { |
| break; |
| } |
| handled = true; |
| if (getCurrentLineTop(buffer, layout) >= targetY) { |
| break; |
| } |
| } |
| return handled; |
| } |
| |
| @Override |
| protected boolean top(TextView widget, Spannable buffer) { |
| if (isSelecting(buffer)) { |
| Selection.extendSelection(buffer, 0); |
| } else { |
| Selection.setSelection(buffer, 0); |
| } |
| return true; |
| } |
| |
| @Override |
| protected boolean bottom(TextView widget, Spannable buffer) { |
| if (isSelecting(buffer)) { |
| Selection.extendSelection(buffer, buffer.length()); |
| } else { |
| Selection.setSelection(buffer, buffer.length()); |
| } |
| return true; |
| } |
| |
| @Override |
| protected boolean lineStart(TextView widget, Spannable buffer) { |
| if (widget.isOffsetMappingAvailable()) { |
| return false; |
| } |
| final Layout layout = widget.getLayout(); |
| if (isSelecting(buffer)) { |
| return Selection.extendToLeftEdge(buffer, layout); |
| } else { |
| return Selection.moveToLeftEdge(buffer, layout); |
| } |
| } |
| |
| @Override |
| protected boolean lineEnd(TextView widget, Spannable buffer) { |
| if (widget.isOffsetMappingAvailable()) { |
| return false; |
| } |
| final Layout layout = widget.getLayout(); |
| if (isSelecting(buffer)) { |
| return Selection.extendToRightEdge(buffer, layout); |
| } else { |
| return Selection.moveToRightEdge(buffer, layout); |
| } |
| } |
| |
| /** {@hide} */ |
| @Override |
| protected boolean leftWord(TextView widget, Spannable buffer) { |
| final int selectionEnd = widget.getSelectionEnd(); |
| final WordIterator wordIterator = widget.getWordIterator(); |
| wordIterator.setCharSequence(buffer, selectionEnd, selectionEnd); |
| return Selection.moveToPreceding(buffer, wordIterator, isSelecting(buffer)); |
| } |
| |
| /** {@hide} */ |
| @Override |
| protected boolean rightWord(TextView widget, Spannable buffer) { |
| final int selectionEnd = widget.getSelectionEnd(); |
| final WordIterator wordIterator = widget.getWordIterator(); |
| wordIterator.setCharSequence(buffer, selectionEnd, selectionEnd); |
| return Selection.moveToFollowing(buffer, wordIterator, isSelecting(buffer)); |
| } |
| |
| @Override |
| protected boolean home(TextView widget, Spannable buffer) { |
| return lineStart(widget, buffer); |
| } |
| |
| @Override |
| protected boolean end(TextView widget, Spannable buffer) { |
| return lineEnd(widget, buffer); |
| } |
| |
| @Override |
| public boolean previousParagraph(@NonNull TextView widget, @NonNull Spannable buffer) { |
| if (widget.isOffsetMappingAvailable()) { |
| return false; |
| } |
| final Layout layout = widget.getLayout(); |
| if (isSelecting(buffer)) { |
| return Selection.extendToParagraphStart(buffer); |
| } else { |
| return Selection.moveToParagraphStart(buffer, layout); |
| } |
| } |
| |
| @Override |
| public boolean nextParagraph(@NonNull TextView widget, @NonNull Spannable buffer) { |
| if (widget.isOffsetMappingAvailable()) { |
| return false; |
| } |
| final Layout layout = widget.getLayout(); |
| if (isSelecting(buffer)) { |
| return Selection.extendToParagraphEnd(buffer); |
| } else { |
| return Selection.moveToParagraphEnd(buffer, layout); |
| } |
| } |
| |
| @Override |
| public boolean onTouchEvent(TextView widget, Spannable buffer, MotionEvent event) { |
| int initialScrollX = -1; |
| int initialScrollY = -1; |
| final int action = event.getAction(); |
| |
| if (action == MotionEvent.ACTION_UP) { |
| initialScrollX = Touch.getInitialScrollX(widget, buffer); |
| initialScrollY = Touch.getInitialScrollY(widget, buffer); |
| } |
| |
| boolean wasTouchSelecting = isSelecting(buffer); |
| boolean handled = Touch.onTouchEvent(widget, buffer, event); |
| |
| if (widget.didTouchFocusSelect()) { |
| return handled; |
| } |
| if (action == MotionEvent.ACTION_DOWN) { |
| // For touch events, the code should run only when selection is active. |
| if (isSelecting(buffer)) { |
| if (!widget.isFocused()) { |
| if (!widget.requestFocus()) { |
| return handled; |
| } |
| } |
| int offset = widget.getOffsetForPosition(event.getX(), event.getY()); |
| buffer.setSpan(LAST_TAP_DOWN, offset, offset, Spannable.SPAN_POINT_POINT); |
| // Disallow intercepting of the touch events, so that |
| // users can scroll and select at the same time. |
| // without this, users would get booted out of select |
| // mode once the view detected it needed to scroll. |
| widget.getParent().requestDisallowInterceptTouchEvent(true); |
| } |
| } else if (widget.isFocused()) { |
| if (action == MotionEvent.ACTION_MOVE) { |
| if (isSelecting(buffer) && handled) { |
| final int startOffset = buffer.getSpanStart(LAST_TAP_DOWN); |
| // Before selecting, make sure we've moved out of the "slop". |
| // handled will be true, if we're in select mode AND we're |
| // OUT of the slop |
| |
| // Turn long press off while we're selecting. User needs to |
| // re-tap on the selection to enable long press |
| widget.cancelLongPress(); |
| |
| // Update selection as we're moving the selection area. |
| |
| // Get the current touch position |
| final int offset = widget.getOffsetForPosition(event.getX(), event.getY()); |
| Selection.setSelection(buffer, Math.min(startOffset, offset), |
| Math.max(startOffset, offset)); |
| return true; |
| } |
| } else if (action == MotionEvent.ACTION_UP) { |
| // If we have scrolled, then the up shouldn't move the cursor, |
| // but we do need to make sure the cursor is still visible at |
| // the current scroll offset to avoid the scroll jumping later |
| // to show it. |
| if ((initialScrollY >= 0 && initialScrollY != widget.getScrollY()) || |
| (initialScrollX >= 0 && initialScrollX != widget.getScrollX())) { |
| widget.moveCursorToVisibleOffset(); |
| return true; |
| } |
| |
| if (wasTouchSelecting) { |
| final int startOffset = buffer.getSpanStart(LAST_TAP_DOWN); |
| final int endOffset = widget.getOffsetForPosition(event.getX(), event.getY()); |
| Selection.setSelection(buffer, Math.min(startOffset, endOffset), |
| Math.max(startOffset, endOffset)); |
| buffer.removeSpan(LAST_TAP_DOWN); |
| } |
| |
| MetaKeyKeyListener.adjustMetaAfterKeypress(buffer); |
| MetaKeyKeyListener.resetLockedMeta(buffer); |
| |
| return true; |
| } |
| } |
| return handled; |
| } |
| |
| @Override |
| public boolean canSelectArbitrarily() { |
| return true; |
| } |
| |
| @Override |
| public void initialize(TextView widget, Spannable text) { |
| Selection.setSelection(text, 0); |
| } |
| |
| @Override |
| public void onTakeFocus(TextView view, Spannable text, int dir) { |
| if ((dir & (View.FOCUS_FORWARD | View.FOCUS_DOWN)) != 0) { |
| if (view.getLayout() == null) { |
| // This shouldn't be null, but do something sensible if it is. |
| Selection.setSelection(text, text.length()); |
| } |
| } else { |
| Selection.setSelection(text, text.length()); |
| } |
| } |
| |
| public static MovementMethod getInstance() { |
| if (sInstance == null) { |
| sInstance = new ArrowKeyMovementMethod(); |
| } |
| |
| return sInstance; |
| } |
| |
| private static final Object LAST_TAP_DOWN = new Object(); |
| private static ArrowKeyMovementMethod sInstance; |
| } |