SessionView.java

/*
   Android Session 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.Bitmap;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Matrix;
import android.graphics.Rect;
import android.graphics.RectF;
import android.graphics.drawable.BitmapDrawable;
import android.text.InputType;
import android.util.AttributeSet;
import android.util.Log;
import android.view.KeyEvent;
import android.view.MotionEvent;
import android.view.ScaleGestureDetector;
import android.view.View;
import android.view.inputmethod.EditorInfo;
import android.view.inputmethod.InputConnection;
 
import androidx.annotation.NonNull;
 
import com.freerdp.freerdpcore.application.SessionState;
import com.freerdp.freerdpcore.services.LibFreeRDP;
import com.freerdp.freerdpcore.utils.DoubleGestureDetector;
import com.freerdp.freerdpcore.utils.GestureDetector;
import com.freerdp.freerdpcore.utils.Mouse;
 
import java.util.Stack;
 
public class SessionView extends View
{
  public static final float MAX_SCALE_FACTOR = 3.0f;
  public static final float MIN_SCALE_FACTOR = 1.0f;
  private static final String TAG = "SessionView";
  private static final float SCALE_FACTOR_DELTA = 0.0001f;
  private static final float TOUCH_SCROLL_DELTA = 10.0f;
  private int width;
  private int height;
  private BitmapDrawable surface;
  private Stack<Rect> invalidRegions;
  private int touchPointerPaddingWidth = 0;
  private int touchPointerPaddingHeight = 0;
  private SessionViewListener sessionViewListener = null;
  // helpers for scaling gesture handling
  private float scaleFactor = 1.0f;
  private Matrix scaleMatrix;
  private Matrix invScaleMatrix;
  private RectF invalidRegionF;
  private GestureDetector gestureDetector;
  private SessionState currentSession;
 
  // private static final String TAG = "FreeRDP.SessionView";
  private DoubleGestureDetector doubleGestureDetector;
  public SessionView(Context context)
  {
    super(context);
    initSessionView(context);
  }
 
  public SessionView(Context context, AttributeSet attrs)
  {
    super(context, attrs);
    initSessionView(context);
  }
 
  public SessionView(Context context, AttributeSet attrs, int defStyle)
  {
    super(context, attrs, defStyle);
    initSessionView(context);
  }
 
  private void initSessionView(Context context)
  {
    invalidRegions = new Stack<>();
    gestureDetector = new GestureDetector(context, new SessionGestureListener(), null, true);
    doubleGestureDetector =
        new DoubleGestureDetector(context, null, new SessionDoubleGestureListener());
 
    scaleFactor = 1.0f;
    scaleMatrix = new Matrix();
    invScaleMatrix = new Matrix();
    invalidRegionF = new RectF();
 
    setSystemUiVisibility(View.SYSTEM_UI_FLAG_HIDE_NAVIGATION |
                          View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY);
  }
 
  /* External Mouse Hover */
  @Override public boolean onHoverEvent(MotionEvent event)
  {
    if (event.getAction() == MotionEvent.ACTION_HOVER_MOVE)
    {
      // Handle hover move event
      float x = event.getX();
      float y = event.getY();
      // Perform actions based on the hover position (x, y)
      MotionEvent mappedEvent = mapTouchEvent(event);
      LibFreeRDP.sendCursorEvent(currentSession.getInstance(), (int)mappedEvent.getX(),
                                 (int)mappedEvent.getY(), Mouse.getMoveEvent());
    }
    // Return true to indicate that you've handled the event
    return true;
  }
 
  public void setScaleGestureDetector(ScaleGestureDetector scaleGestureDetector)
  {
    doubleGestureDetector.setScaleGestureDetector(scaleGestureDetector);
  }
 
  public void setSessionViewListener(SessionViewListener sessionViewListener)
  {
    this.sessionViewListener = sessionViewListener;
  }
 
  public void addInvalidRegion(Rect invalidRegion)
  {
    // correctly transform invalid region depending on current scaling
    invalidRegionF.set(invalidRegion);
    scaleMatrix.mapRect(invalidRegionF);
    invalidRegionF.roundOut(invalidRegion);
 
    invalidRegions.add(invalidRegion);
  }
 
  public void invalidateRegion()
  {
    invalidate(invalidRegions.pop());
  }
 
  public void onSurfaceChange(SessionState session)
  {
    surface = session.getSurface();
    Bitmap bitmap = surface.getBitmap();
    width = bitmap.getWidth();
    height = bitmap.getHeight();
    surface.setBounds(0, 0, width, height);
 
    setMinimumWidth(width);
    setMinimumHeight(height);
 
    requestLayout();
    currentSession = session;
  }
 
  public float getZoom()
  {
    return scaleFactor;
  }
 
  public void setZoom(float factor)
  {
    // calc scale matrix and inverse scale matrix (to correctly transform the view and moues
    // coordinates)
    scaleFactor = factor;
    scaleMatrix.setScale(scaleFactor, scaleFactor);
    invScaleMatrix.setScale(1.0f / scaleFactor, 1.0f / scaleFactor);
 
    // update layout
    requestLayout();
  }
 
  public boolean isAtMaxZoom()
  {
    return (scaleFactor > (MAX_SCALE_FACTOR - SCALE_FACTOR_DELTA));
  }
 
  public boolean isAtMinZoom()
  {
    return (scaleFactor < (MIN_SCALE_FACTOR + SCALE_FACTOR_DELTA));
  }
 
  public boolean zoomIn(float factor)
  {
    boolean res = true;
    scaleFactor += factor;
    if (scaleFactor > (MAX_SCALE_FACTOR - SCALE_FACTOR_DELTA))
    {
      scaleFactor = MAX_SCALE_FACTOR;
      res = false;
    }
    setZoom(scaleFactor);
    return res;
  }
 
  public boolean zoomOut(float factor)
  {
    boolean res = true;
    scaleFactor -= factor;
    if (scaleFactor < (MIN_SCALE_FACTOR + SCALE_FACTOR_DELTA))
    {
      scaleFactor = MIN_SCALE_FACTOR;
      res = false;
    }
    setZoom(scaleFactor);
    return res;
  }
 
  public void setTouchPointerPadding(int width, int height)
  {
    touchPointerPaddingWidth = width;
    touchPointerPaddingHeight = height;
    requestLayout();
  }
 
  public int getTouchPointerPaddingWidth()
  {
    return touchPointerPaddingWidth;
  }
 
  public int getTouchPointerPaddingHeight()
  {
    return touchPointerPaddingHeight;
  }
 
  @Override public void onMeasure(int widthMeasureSpec, int heightMeasureSpec)
  {
    Log.v(TAG, width + "x" + height);
    this.setMeasuredDimension((int)(width * scaleFactor) + touchPointerPaddingWidth,
                              (int)(height * scaleFactor) + touchPointerPaddingHeight);
  }
 
  @Override public void onDraw(@NonNull Canvas canvas)
  {
    super.onDraw(canvas);
 
    canvas.save();
    canvas.concat(scaleMatrix);
    canvas.drawColor(Color.BLACK);
    if (surface != null)
    {
      surface.draw(canvas);
    }
    canvas.restore();
  }
 
  // dirty hack: we call back to our activity and call onBackPressed as this doesn't reach us when
  // the soft keyboard is shown ...
  @Override public boolean dispatchKeyEventPreIme(KeyEvent event)
  {
    if (event.getKeyCode() == KeyEvent.KEYCODE_BACK &&
        event.getAction() == KeyEvent.ACTION_DOWN)
      ((SessionActivity)this.getContext()).onBackPressed();
    return super.dispatchKeyEventPreIme(event);
  }
 
  // perform mapping on the touch event's coordinates according to the current scaling
  private MotionEvent mapTouchEvent(MotionEvent event)
  {
    MotionEvent mappedEvent = MotionEvent.obtain(event);
    float[] coordinates = { mappedEvent.getX(), mappedEvent.getY() };
    invScaleMatrix.mapPoints(coordinates);
    mappedEvent.setLocation(coordinates[0], coordinates[1]);
    return mappedEvent;
  }
 
  // perform mapping on the double touch event's coordinates according to the current scaling
  private MotionEvent mapDoubleTouchEvent(MotionEvent event)
  {
    MotionEvent mappedEvent = MotionEvent.obtain(event);
    float[] coordinates = { (mappedEvent.getX(0) + mappedEvent.getX(1)) / 2,
                          (mappedEvent.getY(0) + mappedEvent.getY(1)) / 2 };
    invScaleMatrix.mapPoints(coordinates);
    mappedEvent.setLocation(coordinates[0], coordinates[1]);
    return mappedEvent;
  }
 
  @Override public boolean onTouchEvent(MotionEvent event)
  {
    boolean res = gestureDetector.onTouchEvent(event);
    res |= doubleGestureDetector.onTouchEvent(event);
    return res;
  }
 
  public interface SessionViewListener {
    void onSessionViewBeginTouch();
 
    void onSessionViewEndTouch();
 
    void onSessionViewLeftTouch(int x, int y, boolean down);
 
    void onSessionViewRightTouch(int x, int y, boolean down);
 
    void onSessionViewMove(int x, int y);
 
    void onSessionViewScroll(boolean down);
  }
 
  private class SessionGestureListener extends GestureDetector.SimpleOnGestureListener
  {
    boolean longPressInProgress = false;
 
    public boolean onDown(MotionEvent e)
    {
      return true;
    }
 
    public boolean onUp(MotionEvent e)
    {
      sessionViewListener.onSessionViewEndTouch();
      return true;
    }
 
    public void onLongPress(MotionEvent e)
    {
      MotionEvent mappedEvent = mapTouchEvent(e);
      sessionViewListener.onSessionViewBeginTouch();
      sessionViewListener.onSessionViewLeftTouch((int)mappedEvent.getX(),
                                                 (int)mappedEvent.getY(), true);
      longPressInProgress = true;
    }
 
    public void onLongPressUp(MotionEvent e)
    {
      MotionEvent mappedEvent = mapTouchEvent(e);
      sessionViewListener.onSessionViewLeftTouch((int)mappedEvent.getX(),
                                                 (int)mappedEvent.getY(), false);
      longPressInProgress = false;
      sessionViewListener.onSessionViewEndTouch();
    }
 
    public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY)
    {
      if (longPressInProgress)
      {
        MotionEvent mappedEvent = mapTouchEvent(e2);
        sessionViewListener.onSessionViewMove((int)mappedEvent.getX(),
                                              (int)mappedEvent.getY());
        return true;
      }
 
      return false;
    }
 
    public boolean onDoubleTap(MotionEvent e)
    {
      // send 2nd click for double click
      MotionEvent mappedEvent = mapTouchEvent(e);
      sessionViewListener.onSessionViewLeftTouch((int)mappedEvent.getX(),
                                                 (int)mappedEvent.getY(), true);
      sessionViewListener.onSessionViewLeftTouch((int)mappedEvent.getX(),
                                                 (int)mappedEvent.getY(), false);
      return true;
    }
 
    public boolean onSingleTapUp(MotionEvent e)
    {
      // send single click
      MotionEvent mappedEvent = mapTouchEvent(e);
      sessionViewListener.onSessionViewBeginTouch();
      switch (e.getButtonState())
      {
        case MotionEvent.BUTTON_PRIMARY:
          sessionViewListener.onSessionViewLeftTouch((int)mappedEvent.getX(),
                                                     (int)mappedEvent.getY(), true);
          sessionViewListener.onSessionViewLeftTouch((int)mappedEvent.getX(),
                                                     (int)mappedEvent.getY(), false);
          break;
        case MotionEvent.BUTTON_SECONDARY:
          sessionViewListener.onSessionViewRightTouch((int)mappedEvent.getX(),
                                                      (int)mappedEvent.getY(), true);
          sessionViewListener.onSessionViewRightTouch((int)mappedEvent.getX(),
                                                      (int)mappedEvent.getY(), false);
          sessionViewListener.onSessionViewLeftTouch((int)mappedEvent.getX(),
                                                     (int)mappedEvent.getY(), true);
          sessionViewListener.onSessionViewLeftTouch((int)mappedEvent.getX(),
                                                     (int)mappedEvent.getY(), false);
          break;
      }
      sessionViewListener.onSessionViewEndTouch();
      return true;
    }
  }
 
  private class SessionDoubleGestureListener
      implements DoubleGestureDetector.OnDoubleGestureListener
  {
    private MotionEvent prevEvent = null;
 
    public boolean onDoubleTouchDown(MotionEvent e)
    {
      sessionViewListener.onSessionViewBeginTouch();
      prevEvent = MotionEvent.obtain(e);
      return true;
    }
 
    public boolean onDoubleTouchUp(MotionEvent e)
    {
      if (prevEvent != null)
      {
        prevEvent.recycle();
        prevEvent = null;
      }
      sessionViewListener.onSessionViewEndTouch();
      return true;
    }
 
    public boolean onDoubleTouchScroll(MotionEvent e1, MotionEvent e2)
    {
      // calc if user scrolled up or down (or if any scrolling happened at all)
      float deltaY = e2.getY() - prevEvent.getY();
      if (deltaY > TOUCH_SCROLL_DELTA)
      {
        sessionViewListener.onSessionViewScroll(true);
        prevEvent.recycle();
        prevEvent = MotionEvent.obtain(e2);
      }
      else if (deltaY < -TOUCH_SCROLL_DELTA)
      {
        sessionViewListener.onSessionViewScroll(false);
        prevEvent.recycle();
        prevEvent = MotionEvent.obtain(e2);
      }
      return true;
    }
 
    public boolean onDoubleTouchSingleTap(MotionEvent e)
    {
      // send single click
      MotionEvent mappedEvent = mapDoubleTouchEvent(e);
      sessionViewListener.onSessionViewRightTouch((int)mappedEvent.getX(),
                                                  (int)mappedEvent.getY(), true);
      sessionViewListener.onSessionViewRightTouch((int)mappedEvent.getX(),
                                                  (int)mappedEvent.getY(), false);
      return true;
    }
  }
 
  @Override public InputConnection onCreateInputConnection(EditorInfo outAttrs)
  {
    super.onCreateInputConnection(outAttrs);
    outAttrs.inputType = InputType.TYPE_CLASS_TEXT;
    return null;
  }
}