1 files changed, 161 insertions, 0 deletions
diff --git a/platform/android/MapboxGLAndroidSDK/src/main/java/com/almeros/android/multitouch/gesturedetectors/BaseGestureDetector.java b/platform/android/MapboxGLAndroidSDK/src/main/java/com/almeros/android/multitouch/gesturedetectors/BaseGestureDetector.java
new file mode 100644
index 0000000000..622e8f759c
--- /dev/null
+++ b/platform/android/MapboxGLAndroidSDK/src/main/java/com/almeros/android/multitouch/gesturedetectors/BaseGestureDetector.java
@@ -0,0 +1,161 @@
+package com.almeros.android.multitouch.gesturedetectors;
+
+import android.content.Context;
+import android.view.MotionEvent;
+
+/**
+ * @author Almer Thie (code.almeros.com) Copyright (c) 2013, Almer Thie
+ *         (code.almeros.com)
+ *
+ *         All rights reserved.
+ *
+ *         Redistribution and use in source and binary forms, with or without
+ *         modification, are permitted provided that the following conditions
+ *         are met:
+ *
+ *         Redistributions of source code must retain the above copyright
+ *         notice, this list of conditions and the following disclaimer.
+ *         Redistributions in binary form must reproduce the above copyright
+ *         notice, this list of conditions and the following disclaimer in the
+ *         documentation and/or other materials provided with the distribution.
+ *
+ *         THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ *         "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ *         LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ *         A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ *         HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ *         INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ *         BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ *         OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ *         AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ *         LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY
+ *         WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ *         POSSIBILITY OF SUCH DAMAGE.
+ */
+public abstract class BaseGestureDetector {
+    protected final Context mContext;
+    protected boolean mGestureInProgress;
+
+    protected MotionEvent mPrevEvent;
+    protected MotionEvent mCurrEvent;
+
+    protected float mCurrPressure;
+    protected float mPrevPressure;
+    protected long mTimeDelta;
+
+    /**
+     * This value is the threshold ratio between the previous combined pressure
+     * and the current combined pressure. When pressure decreases rapidly
+     * between events the position values can often be imprecise, as it usually
+     * indicates that the user is in the process of lifting a pointer off of the
+     * device. This value was tuned experimentally.
+     */
+    protected static final float PRESSURE_THRESHOLD = 0.67f;
+
+    public BaseGestureDetector(Context context) {
+        mContext = context;
+    }
+
+    /**
+     * All gesture detectors need to be called through this method to be able to
+     * detect gestures. This method delegates work to handler methods
+     * (handleStartProgressEvent, handleInProgressEvent) implemented in
+     * extending classes.
+     *
+     * @param event MotionEvent
+     * @return {@code true} as handled
+     */
+    public boolean onTouchEvent(MotionEvent event) {
+        final int actionCode = event.getAction() & MotionEvent.ACTION_MASK;
+        if (!mGestureInProgress) {
+            handleStartProgressEvent(actionCode, event);
+        } else {
+            handleInProgressEvent(actionCode, event);
+        }
+        return true;
+    }
+
+    /**
+     * Called when the current event occurred when NO gesture is in progress
+     * yet. The handling in this implementation may set the gesture in progress
+     * (via mGestureInProgress) or out of progress
+     *
+     * @param actionCode Action Code from MotionEvent
+     * @param event MotionEvent
+     */
+    protected abstract void handleStartProgressEvent(int actionCode,
+            MotionEvent event);
+
+    /**
+     * Called when the current event occurred when a gesture IS in progress. The
+     * handling in this implementation may set the gesture out of progress (via
+     * mGestureInProgress).
+     *
+     *
+     * @param actionCode Action Code from MotionEvent
+     * @param event MotionEvent
+     */
+    protected abstract void handleInProgressEvent(int actionCode,
+            MotionEvent event);
+
+    protected void updateStateByEvent(MotionEvent curr) {
+        final MotionEvent prev = mPrevEvent;
+
+        // Reset mCurrEvent
+        if (mCurrEvent != null) {
+            mCurrEvent.recycle();
+            mCurrEvent = null;
+        }
+        mCurrEvent = MotionEvent.obtain(curr);
+
+        // Delta time
+        mTimeDelta = curr.getEventTime() - prev.getEventTime();
+
+        // Pressure
+        mCurrPressure = curr.getPressure(curr.getActionIndex());
+        mPrevPressure = prev.getPressure(prev.getActionIndex());
+    }
+
+    protected void resetState() {
+        if (mPrevEvent != null) {
+            mPrevEvent.recycle();
+            mPrevEvent = null;
+        }
+        if (mCurrEvent != null) {
+            mCurrEvent.recycle();
+            mCurrEvent = null;
+        }
+        mGestureInProgress = false;
+    }
+
+    /**
+     * Returns {@code true} if a gesture is currently in progress.
+     *
+     * @return {@code true} if a gesture is currently in progress, {@code false}
+     *         otherwise.
+     */
+    public boolean isInProgress() {
+        return mGestureInProgress;
+    }
+
+    /**
+     * Return the time difference in milliseconds between the previous accepted
+     * GestureDetector event and the current GestureDetector event.
+     *
+     * @return Time difference since the last move event in milliseconds.
+     */
+    public long getTimeDelta() {
+        return mTimeDelta;
+    }
+
+    /**
+     * Return the event time of the current GestureDetector event being
+     * processed.
+     *
+     * @return Current GestureDetector event time in milliseconds.
+     */
+    public long getEventTime() {
+        return mCurrEvent.getEventTime();
+    }
+
+}