Merge "Adding SecureTouchListener to drop suspicious touches" into oc-dev

packages/SettingsLib/src/com/android/settingslib/SecureTouchListener.java

@@ -0,0 +1,44 @@
+package com.android.settingslib;
+
+import android.os.SystemClock;
+import android.view.MotionEvent;
+import android.view.View;
+import android.widget.Toast;
+
+/**
+ * A touch listener which consumes touches when another window is partly or wholly obscuring the
+ * window containing the view this listener is attached to.
+ * Optionally accepts a string to show the user as a toast when consuming an insecure touch
+ */
+public class SecureTouchListener implements View.OnTouchListener {
+
+    private static final long TAP_DEBOUNCE_TIME = 2000;
+    private long mLastToastTime = 0;
+    private String mWarningText;
+
+    public SecureTouchListener() {
+        this(null);
+    }
+
+    public SecureTouchListener(String warningText) {
+        mWarningText = warningText;
+    }
+
+    @Override
+    public boolean onTouch(View v, MotionEvent event) {
+        if ((event.getFlags() & MotionEvent.FLAG_WINDOW_IS_OBSCURED) != 0
+                || (event.getFlags() & MotionEvent.FLAG_WINDOW_IS_PARTIALLY_OBSCURED) != 0) {
+            if (mWarningText != null) {
+                // Show a toast warning the user
+                final long currentTime = SystemClock.uptimeMillis();
+                if (currentTime - mLastToastTime > TAP_DEBOUNCE_TIME) {
+                    mLastToastTime = currentTime;
+                    Toast.makeText(v.getContext(), mWarningText, Toast.LENGTH_SHORT).show();
+                }
+            }
+            // Consume the touch event
+            return true;
+        }
+        return false;
+    }
+}