TouchPointerView.java

/*
   Android Touch Pointer view
 
   Copyright 2013 Thincast Technologies GmbH, Author: Martin Fleisz
 
   This Source Code Form is subject to the terms of the Mozilla Public License, v. 2.0.
   If a copy of the MPL was not distributed with this file, You can obtain one at
   http://mozilla.org/MPL/2.0/.
*/
 
package com.freerdp.freerdpcore.presentation;
 
import android.content.Context;
import android.graphics.Matrix;
import android.graphics.RectF;
import android.os.Handler;
import android.os.Looper;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.widget.ImageView;
 
import com.freerdp.freerdpcore.R;
import com.freerdp.freerdpcore.utils.GestureDetector;
 
public class TouchPointerView extends ImageView
{
 
  private static final int POINTER_ACTION_CURSOR = 0;
  private static final int POINTER_ACTION_CLOSE = 3;
 
  // the touch pointer consists of 9 quadrants with the following functionality:
  //
  // -------------
  // | 0 | 1 | 2 |
  // -------------
  // | 3 | 4 | 5 |
  // -------------
  // | 6 | 7 | 8 |
  // -------------
  //
  // 0 ... contains the actual pointer (the tip must be centered in the quadrant)
  // 1 ... is left empty
  // 2, 3, 5, 6, 7, 8 ... function quadrants that issue a callback
  // 4 ... pointer center used for left clicks and to drag the pointer
  private static final int POINTER_ACTION_RCLICK = 2;
  private static final int POINTER_ACTION_LCLICK = 4;
  private static final int POINTER_ACTION_MOVE = 4;
  private static final int POINTER_ACTION_SCROLL = 5;
  private static final int POINTER_ACTION_RESET = 6;
  private static final int POINTER_ACTION_KEYBOARD = 7;
  private static final int POINTER_ACTION_EXTKEYBOARD = 8;
  private static final float SCROLL_DELTA = 10.0f;
  private static final int DEFAULT_TOUCH_POINTER_RESTORE_DELAY = 150;
  private RectF pointerRect;
  private final RectF[] pointerAreaRects = new RectF[9];
  private Matrix translationMatrix;
  private boolean pointerMoving = false;
  private boolean pointerScrolling = false;
  private TouchPointerListener listener = null;
  private final Handler uiHandler = new Handler(Looper.getMainLooper());
  private final Runnable restorePointerImage =
      () -> setPointerImage(R.drawable.touch_pointer_default);
  // gesture detection
  private GestureDetector gestureDetector;
  public TouchPointerView(Context context)
  {
    super(context);
    initTouchPointer(context);
  }
 
  public TouchPointerView(Context context, AttributeSet attrs)
  {
    super(context, attrs);
    initTouchPointer(context);
  }
 
  public TouchPointerView(Context context, AttributeSet attrs, int defStyle)
  {
    super(context, attrs, defStyle);
    initTouchPointer(context);
  }
 
  private void initTouchPointer(Context context)
  {
    gestureDetector =
        new GestureDetector(context, new TouchPointerGestureListener(), null, true);
    gestureDetector.setLongPressTimeout(500);
    translationMatrix = new Matrix();
    setScaleType(ScaleType.MATRIX);
    setImageMatrix(translationMatrix);
 
    // init rects
    final float rectSizeWidth = (float)getDrawable().getIntrinsicWidth() / 3.0f;
    final float rectSizeHeight = (float)getDrawable().getIntrinsicWidth() / 3.0f;
    for (int i = 0; i < 3; i++)
    {
      for (int j = 0; j < 3; j++)
      {
        int left = (int)(j * rectSizeWidth);
        int top = (int)(i * rectSizeHeight);
        int right = left + (int)rectSizeWidth;
        int bottom = top + (int)rectSizeHeight;
        pointerAreaRects[i * 3 + j] = new RectF(left, top, right, bottom);
      }
    }
    pointerRect =
        new RectF(0, 0, getDrawable().getIntrinsicWidth(), getDrawable().getIntrinsicHeight());
  }
 
  public void setTouchPointerListener(TouchPointerListener listener)
  {
    this.listener = listener;
  }
 
  public int getPointerWidth()
  {
    return getDrawable().getIntrinsicWidth();
  }
 
  public int getPointerHeight()
  {
    return getDrawable().getIntrinsicHeight();
  }
 
  public float[] getPointerPosition()
  {
    float[] curPos = new float[2];
    translationMatrix.mapPoints(curPos);
    return curPos;
  }
 
  private void movePointer(float deltaX, float deltaY)
  {
    translationMatrix.postTranslate(deltaX, deltaY);
    setImageMatrix(translationMatrix);
  }
 
  private void ensureVisibility(int screen_width, int screen_height)
  {
    float[] curPos = new float[2];
    translationMatrix.mapPoints(curPos);
 
    if (curPos[0] > (screen_width - pointerRect.width()))
      curPos[0] = screen_width - pointerRect.width();
    if (curPos[0] < 0)
      curPos[0] = 0;
    if (curPos[1] > (screen_height - pointerRect.height()))
      curPos[1] = screen_height - pointerRect.height();
    if (curPos[1] < 0)
      curPos[1] = 0;
 
    translationMatrix.setTranslate(curPos[0], curPos[1]);
    setImageMatrix(translationMatrix);
  }
 
  private void displayPointerImageAction(int resId)
  {
    setPointerImage(resId);
    uiHandler.removeCallbacks(restorePointerImage);
    uiHandler.postDelayed(restorePointerImage, DEFAULT_TOUCH_POINTER_RESTORE_DELAY);
  }
 
  private void setPointerImage(int resId)
  {
    setImageResource(resId);
  }
 
  // returns the pointer area with the current translation matrix applied
  private RectF getCurrentPointerArea(int area)
  {
    RectF transRect = new RectF(pointerAreaRects[area]);
    translationMatrix.mapRect(transRect);
    return transRect;
  }
 
  private boolean pointerAreaTouched(MotionEvent event, int area)
  {
    RectF transRect = new RectF(pointerAreaRects[area]);
    translationMatrix.mapRect(transRect);
    return transRect.contains(event.getX(), event.getY());
  }
 
  private boolean pointerTouched(MotionEvent event)
  {
    RectF transRect = new RectF(pointerRect);
    translationMatrix.mapRect(transRect);
    return transRect.contains(event.getX(), event.getY());
  }
 
  @Override public boolean onTouchEvent(MotionEvent event)
  {
    // check if pointer is being moved or if we are in scroll mode or if the pointer is touched
    if (!pointerMoving && !pointerScrolling && !pointerTouched(event))
      return false;
    return gestureDetector.onTouchEvent(event);
  }
 
  @Override protected void onLayout(boolean changed, int left, int top, int right, int bottom)
  {
    // ensure touch pointer is visible
    if (changed)
      ensureVisibility(right - left, bottom - top);
  }
 
  // touch pointer listener - is triggered if an action field is
  public interface TouchPointerListener {
    void onTouchPointerClose();
 
    void onTouchPointerLeftClick(int x, int y, boolean down);
 
    void onTouchPointerRightClick(int x, int y, boolean down);
 
    void onTouchPointerMove(int x, int y);
 
    void onTouchPointerScroll(boolean down);
 
    void onTouchPointerToggleKeyboard();
 
    void onTouchPointerToggleExtKeyboard();
 
    void onTouchPointerResetScrollZoom();
  }
 
  private class TouchPointerGestureListener extends GestureDetector.SimpleOnGestureListener
  {
 
    private MotionEvent prevEvent = null;
 
    public boolean onDown(MotionEvent e)
    {
      if (pointerAreaTouched(e, POINTER_ACTION_MOVE))
      {
        prevEvent = MotionEvent.obtain(e);
        pointerMoving = true;
      }
      else if (pointerAreaTouched(e, POINTER_ACTION_SCROLL))
      {
        prevEvent = MotionEvent.obtain(e);
        pointerScrolling = true;
        setPointerImage(R.drawable.touch_pointer_scroll);
      }
 
      return true;
    }
 
    public boolean onUp(MotionEvent e)
    {
      if (prevEvent != null)
      {
        prevEvent.recycle();
        prevEvent = null;
      }
 
      if (pointerScrolling)
        setPointerImage(R.drawable.touch_pointer_default);
 
      pointerMoving = false;
      pointerScrolling = false;
      return true;
    }
 
    public void onLongPress(MotionEvent e)
    {
      if (pointerAreaTouched(e, POINTER_ACTION_LCLICK))
      {
        setPointerImage(R.drawable.touch_pointer_active);
        pointerMoving = true;
        RectF rect = getCurrentPointerArea(POINTER_ACTION_CURSOR);
        listener.onTouchPointerLeftClick((int)rect.centerX(), (int)rect.centerY(), true);
      }
    }
 
    public void onLongPressUp(MotionEvent e)
    {
      if (pointerMoving)
      {
        setPointerImage(R.drawable.touch_pointer_default);
        pointerMoving = false;
        RectF rect = getCurrentPointerArea(POINTER_ACTION_CURSOR);
        listener.onTouchPointerLeftClick((int)rect.centerX(), (int)rect.centerY(), false);
      }
    }
 
    public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY)
    {
      if (pointerMoving)
      {
        // move pointer graphics
        movePointer((int)(e2.getX() - prevEvent.getX()),
                    (int)(e2.getY() - prevEvent.getY()));
        prevEvent.recycle();
        prevEvent = MotionEvent.obtain(e2);
 
        // send move notification
        RectF rect = getCurrentPointerArea(POINTER_ACTION_CURSOR);
        listener.onTouchPointerMove((int)rect.centerX(), (int)rect.centerY());
        return true;
      }
      else if (pointerScrolling)
      {
        // calc if user scrolled up or down (or if any scrolling happened at all)
        float deltaY = e2.getY() - prevEvent.getY();
        if (deltaY > SCROLL_DELTA)
        {
          listener.onTouchPointerScroll(true);
          prevEvent.recycle();
          prevEvent = MotionEvent.obtain(e2);
        }
        else if (deltaY < -SCROLL_DELTA)
        {
          listener.onTouchPointerScroll(false);
          prevEvent.recycle();
          prevEvent = MotionEvent.obtain(e2);
        }
        return true;
      }
      return false;
    }
 
    public boolean onSingleTapUp(MotionEvent e)
    {
      // look what area got touched and fire actions accordingly
      if (pointerAreaTouched(e, POINTER_ACTION_CLOSE))
        listener.onTouchPointerClose();
      else if (pointerAreaTouched(e, POINTER_ACTION_LCLICK))
      {
        displayPointerImageAction(R.drawable.touch_pointer_lclick);
        RectF rect = getCurrentPointerArea(POINTER_ACTION_CURSOR);
        listener.onTouchPointerLeftClick((int)rect.centerX(), (int)rect.centerY(), true);
        listener.onTouchPointerLeftClick((int)rect.centerX(), (int)rect.centerY(), false);
      }
      else if (pointerAreaTouched(e, POINTER_ACTION_RCLICK))
      {
        displayPointerImageAction(R.drawable.touch_pointer_rclick);
        RectF rect = getCurrentPointerArea(POINTER_ACTION_CURSOR);
        listener.onTouchPointerRightClick((int)rect.centerX(), (int)rect.centerY(), true);
        listener.onTouchPointerRightClick((int)rect.centerX(), (int)rect.centerY(), false);
      }
      else if (pointerAreaTouched(e, POINTER_ACTION_KEYBOARD))
      {
        displayPointerImageAction(R.drawable.touch_pointer_keyboard);
        listener.onTouchPointerToggleKeyboard();
      }
      else if (pointerAreaTouched(e, POINTER_ACTION_EXTKEYBOARD))
      {
        displayPointerImageAction(R.drawable.touch_pointer_extkeyboard);
        listener.onTouchPointerToggleExtKeyboard();
      }
      else if (pointerAreaTouched(e, POINTER_ACTION_RESET))
      {
        displayPointerImageAction(R.drawable.touch_pointer_reset);
        listener.onTouchPointerResetScrollZoom();
      }
 
      return true;
    }
 
    public boolean onDoubleTap(MotionEvent e)
    {
      // issue a double click notification if performed in center quadrant
      if (pointerAreaTouched(e, POINTER_ACTION_LCLICK))
      {
        RectF rect = getCurrentPointerArea(POINTER_ACTION_CURSOR);
        listener.onTouchPointerLeftClick((int)rect.centerX(), (int)rect.centerY(), true);
        listener.onTouchPointerLeftClick((int)rect.centerX(), (int)rect.centerY(), false);
      }
      return true;
    }
  }
}