Make up/down movement of multilength lines remember position (6c66f867) · Commits · e / os / android_frameworks_base

api/test-current.txt

+7 −0

Original line number	Diff line number	Diff line
		@@ -41709,6 +41709,13 @@ package android.text {
		field public static final java.lang.Object SELECTION_START;
		}

		public static final class Selection.MemoryTextWatcher implements android.text.TextWatcher {
		ctor public Selection.MemoryTextWatcher();
		method public void afterTextChanged(android.text.Editable);
		method public void beforeTextChanged(java.lang.CharSequence, int, int, int);
		method public void onTextChanged(java.lang.CharSequence, int, int, int);
		}

		public abstract interface SpanWatcher implements android.text.NoCopySpan {
		method public abstract void onSpanAdded(android.text.Spannable, java.lang.Object, int, int);
		method public abstract void onSpanChanged(android.text.Spannable, java.lang.Object, int, int, int, int);

core/java/android/text/Selection.java

+128 −55

Original line number	Diff line number	Diff line
		@@ -16,6 +16,8 @@

		package android.text;

		import android.annotation.TestApi;

		import java.text.BreakIterator;


		@@ -35,9 +37,9 @@ public class Selection {
		* there is no selection or cursor.
		*/
		public static final int getSelectionStart(CharSequence text) {
		if (text instanceof Spanned)
		if (text instanceof Spanned) {
		return ((Spanned) text).getSpanStart(SELECTION_START);
		else
		}
		return -1;
		}

		@@ -46,9 +48,16 @@ public class Selection {
		* there is no selection or cursor.
		*/
		public static final int getSelectionEnd(CharSequence text) {
		if (text instanceof Spanned)
		if (text instanceof Spanned) {
		return ((Spanned) text).getSpanStart(SELECTION_END);
		else
		}
		return -1;
		}

		private static int getSelectionMemory(CharSequence text) {
		if (text instanceof Spanned) {
		return ((Spanned) text).getSpanStart(SELECTION_MEMORY);
		}
		return -1;
		}

		@@ -65,6 +74,14 @@ public class Selection {
		* to <code>stop</code>.
		*/
		public static void setSelection(Spannable text, int start, int stop) {
		setSelection(text, start, stop, -1);
		}

		/**
		* Set the selection anchor to <code>start</code>, the selection edge
		* to <code>stop</code> and the memory horizontal to <code>memory</code>.
		*/
		private static void setSelection(Spannable text, int start, int stop, int memory) {
		// int len = text.length();
		// start = pin(start, 0, len); XXX remove unless we really need it
		// stop = pin(stop, 0, len);
		@@ -75,8 +92,56 @@ public class Selection {
		if (ostart != start \|\| oend != stop) {
		text.setSpan(SELECTION_START, start, start,
		Spanned.SPAN_POINT_POINT \| Spanned.SPAN_INTERMEDIATE);
		text.setSpan(SELECTION_END, stop, stop,
		Spanned.SPAN_POINT_POINT);
		text.setSpan(SELECTION_END, stop, stop, Spanned.SPAN_POINT_POINT);
		updateMemory(text, memory);
		}
		}

		/**
		* Update the memory position for text. This is used to ensure vertical navigation of lines
		* with different lengths behaves as expected and remembers the longest horizontal position
		* seen during a vertical traversal.
		*/
		private static void updateMemory(Spannable text, int memory) {
		if (memory > -1) {
		int currentMemory = getSelectionMemory(text);
		if (memory != currentMemory) {
		text.setSpan(SELECTION_MEMORY, memory, memory, Spanned.SPAN_POINT_POINT);
		if (currentMemory == -1) {
		// This is the first value, create a watcher.
		final TextWatcher watcher = new MemoryTextWatcher();
		text.setSpan(watcher, 0, text.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
		}
		}
		} else {
		removeMemory(text);
		}
		}

		private static void removeMemory(Spannable text) {
		text.removeSpan(SELECTION_MEMORY);
		MemoryTextWatcher[] watchers = text.getSpans(0, text.length(), MemoryTextWatcher.class);
		for (MemoryTextWatcher watcher : watchers) {
		text.removeSpan(watcher);
		}
		}

		/**
		* @hide
		*/
		@TestApi
		public static final class MemoryTextWatcher implements TextWatcher {

		@Override
		public void beforeTextChanged(CharSequence s, int start, int count, int after) {}

		@Override
		public void onTextChanged(CharSequence s, int start, int before, int count) {}

		@Override
		public void afterTextChanged(Editable s) {
		s.removeSpan(SELECTION_MEMORY);
		s.removeSpan(this);
		}
		}

		@@ -98,9 +163,18 @@ public class Selection {
		* Move the selection edge to offset <code>index</code>.
		*/
		public static final void extendSelection(Spannable text, int index) {
		if (text.getSpanStart(SELECTION_END) != index)
		extendSelection(text, index, -1);
		}

		/**
		* Move the selection edge to offset <code>index</code> and update the memory horizontal.
		*/
		private static void extendSelection(Spannable text, int index, int memory) {
		if (text.getSpanStart(SELECTION_END) != index) {
		text.setSpan(SELECTION_END, index, index, Spanned.SPAN_POINT_POINT);
		}
		updateMemory(text, memory);
		}

		/**
		* Remove the selection or cursor, if any, from the text.
		@@ -108,6 +182,7 @@ public class Selection {
		public static final void removeSelection(Spannable text) {
		text.removeSpan(SELECTION_START);
		text.removeSpan(SELECTION_END);
		removeMemory(text);
		}

		/*
		@@ -138,17 +213,8 @@ public class Selection {
		int line = layout.getLineForOffset(end);

		if (line > 0) {
		int move;

		if (layout.getParagraphDirection(line) ==
		layout.getParagraphDirection(line - 1)) {
		float h = layout.getPrimaryHorizontal(end);
		move = layout.getOffsetForHorizontal(line - 1, h);
		} else {
		move = layout.getLineStart(line - 1);
		}

		setSelection(text, move);
		setSelectionAndMemory(
		text, layout, line, end, -1 /* direction /, false / extend */);
		return true;
		} else if (end != 0) {
		setSelection(text, 0);
		@@ -159,6 +225,40 @@ public class Selection {
		return false;
		}

		/**
		* Calculate the movement and memory positions needed, and set or extend the selection.
		*/
		private static void setSelectionAndMemory(Spannable text, Layout layout, int line, int end,
		int direction, boolean extend) {
		int move;
		int newMemory;

		if (layout.getParagraphDirection(line)
		== layout.getParagraphDirection(line + direction)) {
		int memory = getSelectionMemory(text);
		if (memory > -1) {
		// We have a memory position
		float h = layout.getPrimaryHorizontal(memory);
		move = layout.getOffsetForHorizontal(line + direction, h);
		newMemory = memory;
		} else {
		// Create a new memory position
		float h = layout.getPrimaryHorizontal(end);
		move = layout.getOffsetForHorizontal(line + direction, h);
		newMemory = end;
		}
		} else {
		move = layout.getLineStart(line + direction);
		newMemory = -1;
		}

		if (extend) {
		extendSelection(text, move, newMemory);
		} else {
		setSelection(text, move, move, newMemory);
		}
		}

		/**
		* Move the cursor to the buffer offset physically below the current
		* offset, to the end of the buffer if it is on the bottom line but
		@@ -184,17 +284,8 @@ public class Selection {
		int line = layout.getLineForOffset(end);

		if (line < layout.getLineCount() - 1) {
		int move;

		if (layout.getParagraphDirection(line) ==
		layout.getParagraphDirection(line + 1)) {
		float h = layout.getPrimaryHorizontal(end);
		move = layout.getOffsetForHorizontal(line + 1, h);
		} else {
		move = layout.getLineStart(line + 1);
		}

		setSelection(text, move);
		setSelectionAndMemory(
		text, layout, line, end, 1 /* direction /, false / extend */);
		return true;
		} else if (end != text.length()) {
		setSelection(text, text.length());
		@@ -263,17 +354,7 @@ public class Selection {
		int line = layout.getLineForOffset(end);

		if (line > 0) {
		int move;

		if (layout.getParagraphDirection(line) ==
		layout.getParagraphDirection(line - 1)) {
		float h = layout.getPrimaryHorizontal(end);
		move = layout.getOffsetForHorizontal(line - 1, h);
		} else {
		move = layout.getLineStart(line - 1);
		}

		extendSelection(text, move);
		setSelectionAndMemory(text, layout, line, end, -1 /* direction /, true / extend */);
		return true;
		} else if (end != 0) {
		extendSelection(text, 0);
		@@ -292,20 +373,10 @@ public class Selection {
		int line = layout.getLineForOffset(end);

		if (line < layout.getLineCount() - 1) {
		int move;

		if (layout.getParagraphDirection(line) ==
		layout.getParagraphDirection(line + 1)) {
		float h = layout.getPrimaryHorizontal(end);
		move = layout.getOffsetForHorizontal(line + 1, h);
		} else {
		move = layout.getLineStart(line + 1);
		}

		extendSelection(text, move);
		setSelectionAndMemory(text, layout, line, end, 1 /* direction /, true / extend */);
		return true;
		} else if (end != text.length()) {
		extendSelection(text, text.length());
		extendSelection(text, text.length(), -1);
		return true;
		}

		@@ -466,6 +537,8 @@ public class Selection {

		private static final class START implements NoCopySpan { }
		private static final class END implements NoCopySpan { }
		private static final class MEMORY implements NoCopySpan { }
		private static final Object SELECTION_MEMORY = new MEMORY();

		/*
		* Public constants