Add scroll wheel support to TextView. (8f34567c) · Commits · e / os / android_frameworks_base

api/current.xml

+35 −1

Original line number	Diff line number	Diff line
		@@ -198789,6 +198789,23 @@
		<parameter name="buffer" type="android.text.Spannable">
		</parameter>
		</method>
		<method name="onGenericMotionEvent"
		return="boolean"
		abstract="false"
		native="false"
		synchronized="false"
		static="false"
		final="false"
		deprecated="not deprecated"
		visibility="public"
		>
		<parameter name="widget" type="android.widget.TextView">
		</parameter>
		<parameter name="text" type="android.text.Spannable">
		</parameter>
		<parameter name="event" type="android.view.MotionEvent">
		</parameter>
		</method>
		<method name="onKeyDown"
		return="boolean"
		abstract="false"
		@@ -199862,6 +199879,23 @@
		<parameter name="text" type="android.text.Spannable">
		</parameter>
		</method>
		<method name="onGenericMotionEvent"
		return="boolean"
		abstract="true"
		native="false"
		synchronized="false"
		static="false"
		final="false"
		deprecated="not deprecated"
		visibility="public"
		>
		<parameter name="widget" type="android.widget.TextView">
		</parameter>
		<parameter name="text" type="android.text.Spannable">
		</parameter>
		<parameter name="event" type="android.view.MotionEvent">
		</parameter>
		</method>
		<method name="onKeyDown"
		return="boolean"
		abstract="true"
		@@ -266599,7 +266633,7 @@
		deprecated="not deprecated"
		visibility="public"
		>
		<parameter name="t" type="T">
		<parameter name="arg0" type="T">
		</parameter>
		</method>
		</interface>

core/java/android/text/method/BaseMovementMethod.java

+306 −0

Original line number	Diff line number	Diff line
		@@ -18,6 +18,7 @@ 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;
		@@ -88,6 +89,39 @@ public class BaseMovementMethod implements MovementMethod {
		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.
		@@ -342,4 +376,276 @@ public class BaseMovementMethod implements MovementMethod {
		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;
		}
		}

core/java/android/text/method/MovementMethod.java

+1 −0

Original line number	Diff line number	Diff line
		@@ -47,6 +47,7 @@ public interface MovementMethod {
		public void onTakeFocus(TextView widget, Spannable text, int direction);
		public boolean onTrackballEvent(TextView widget, Spannable text, MotionEvent event);
		public boolean onTouchEvent(TextView widget, Spannable text, MotionEvent event);
		public boolean onGenericMotionEvent(TextView widget, Spannable text, MotionEvent event);

		/**
		* Returns true if this movement method allows arbitrary selection

core/java/android/text/method/ScrollingMovementMethod.java

+10 −145

Original line number	Diff line number	Diff line
		@@ -25,189 +25,54 @@ import android.view.View;
		* A movement method that interprets movement keys by scrolling the text buffer.
		*/
		public class ScrollingMovementMethod extends BaseMovementMethod implements MovementMethod {
		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;
		}

		@Override
		protected boolean left(TextView widget, Spannable buffer) {
		final int minScrollX = getScrollBoundsLeft(widget);
		int scrollX = widget.getScrollX();
		if (scrollX > minScrollX) {
		scrollX = Math.max(scrollX - getCharacterWidth(widget), minScrollX);
		widget.scrollTo(scrollX, widget.getScrollY());
		return true;
		}
		return false;
		return scrollLeft(widget, buffer, 1);
		}

		@Override
		protected boolean right(TextView widget, Spannable buffer) {
		final int maxScrollX = getScrollBoundsRight(widget) - getInnerWidth(widget);
		int scrollX = widget.getScrollX();
		if (scrollX < maxScrollX) {
		scrollX = Math.min(scrollX + getCharacterWidth(widget), maxScrollX);
		widget.scrollTo(scrollX, widget.getScrollY());
		return true;
		}
		return false;
		return scrollRight(widget, buffer, 1);
		}

		@Override
		protected boolean up(TextView widget, Spannable buffer) {
		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) {
		Touch.scrollTo(widget, layout, widget.getScrollX(), layout.getLineTop(topLine));
		return true;
		}
		return false;
		return scrollUp(widget, buffer, 1);
		}

		@Override
		protected boolean down(TextView widget, Spannable buffer) {
		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;
		}
		if (bottomLine <= layout.getLineCount() - 1) {
		Touch.scrollTo(widget, layout, widget.getScrollX(),
		layout.getLineTop(bottomLine + 1) - innerHeight);
		return true;
		}
		return false;
		return scrollDown(widget, buffer, 1);
		}

		@Override
		protected boolean pageUp(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;
		return scrollPageUp(widget, buffer);
		}

		@Override
		protected boolean pageDown(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;
		return scrollPageDown(widget, buffer);
		}

		@Override
		protected boolean top(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;
		return scrollTop(widget, buffer);
		}

		@Override
		protected boolean bottom(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;
		return scrollBottom(widget, buffer);
		}

		@Override
		protected boolean lineStart(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;
		return scrollLineStart(widget, buffer);
		}

		@Override
		protected boolean lineEnd(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;
		return scrollLineEnd(widget, buffer);
		}

		@Override

core/java/android/widget/TextView.java

+16 −0

Original line number	Diff line number	Diff line
		@@ -7389,6 +7389,22 @@ public class TextView extends View implements ViewTreeObserver.OnPreDrawListener
		return superResult;
		}

		@Override
		public boolean onGenericMotionEvent(MotionEvent event) {
		if (mMovement != null && mText instanceof Spannable && mLayout != null) {
		try {
		if (mMovement.onGenericMotionEvent(this, (Spannable) mText, event)) {
		return true;
		}
		} catch (AbstractMethodError ex) {
		// onGenericMotionEvent was added to the MovementMethod interface in API 12.
		// Ignore its absence in case third party applications implemented the
		// interface directly.
		}
		}
		return super.onGenericMotionEvent(event);
		}

		private void prepareCursorControllers() {
		boolean windowSupportsHandles = false;