Fixes #134: Change ChatBox container to a custom view and listen for swipe on chatBox

Author: kunall17

app/src/main/java/com/zulip/android/activities/ZulipActivity.java

@@ -85,6 +85,7 @@
 import com.zulip.android.R;
 import com.zulip.android.models.Stream;
 import com.zulip.android.networking.AsyncSend;
+import com.zulip.android.util.SwipeRemoveLinearLayout;
 import com.zulip.android.util.ZLog;
 import com.zulip.android.ZulipApp;
 import com.zulip.android.gcm.GcmBroadcastReceiver;
@@ -99,7 +100,7 @@
  * messages
  * */
 public class ZulipActivity extends AppCompatActivity implements
-        MessageListFragment.Listener, NarrowListener {
+        MessageListFragment.Listener, NarrowListener, SwipeRemoveLinearLayout.leftToRightSwipeListener {
 
     private static final String NARROW = "narrow";
     private static final String PARAMS = "params";
@@ -121,8 +122,8 @@ public class ZulipActivity extends AppCompatActivity implements
     private ActionBarDrawerToggle drawerToggle;
     private ExpandableListView streamsDrawer;
     private static final Interpolator FAST_OUT_SLOW_IN_INTERPOLATOR = new FastOutSlowInInterpolator();
-    private LinearLayout chatBox;
-    public FloatingActionButton fab;
+    private SwipeRemoveLinearLayout chatBox;
+    private FloatingActionButton fab;
     private CountDownTimer fabHidder;
     private boolean isTextFieldFocused = false;
     private static final int HIDE_FAB_AFTER_SEC = 5;
@@ -160,6 +161,11 @@ public void onReceive(Context contenxt, Intent intent) {
         }
     };
 
+    @Override
+    public void removeChatBox() {
+        chatBox.setVisibility(View.GONE);
+    }
+
     // Intent Extra constants
     public enum Flag {
         RESET_DATABASE,

app/src/main/java/com/zulip/android/util/SwipeRemoveLinearLayout.java

@@ -0,0 +1,62 @@
+package com.zulip.android.util;
+
+import android.content.Context;
+import android.util.AttributeSet;
+import android.util.DisplayMetrics;
+import android.view.MotionEvent;
+import android.widget.LinearLayout;
+
+public class SwipeRemoveLinearLayout extends LinearLayout {
+
+    private float x1, x2;
+    private static int MIN_DISTANCE = 150;
+    private leftToRightSwipeListener leftToRightSwipeListen;
+
+    public SwipeRemoveLinearLayout(Context context) {
+        super(context);
+        setupMinimumDistance();
+    }
+
+    public SwipeRemoveLinearLayout(Context context, AttributeSet attrs) {
+        super(context, attrs);
+        setupMinimumDistance();
+    }
+
+    public SwipeRemoveLinearLayout(Context context, AttributeSet attrs, int defStyleAttr) {
+        super(context, attrs, defStyleAttr);
+        setupMinimumDistance();
+    }
+
+    private void setupMinimumDistance() {
+        DisplayMetrics metrics = getResources().getDisplayMetrics();
+        MIN_DISTANCE = metrics.widthPixels / 8;
+    }
+
+    @Override
+    public boolean onInterceptTouchEvent(MotionEvent ev) {
+
+        switch (ev.getAction()) {
+            case MotionEvent.ACTION_DOWN:
+                x1 = ev.getX();
+                break;
+            case MotionEvent.ACTION_UP:
+                x2 = ev.getX();
+                float deltaX = x2 - x1;
+                if (Math.abs(deltaX) > MIN_DISTANCE) {
+                    //swiping right to left
+                    leftToRightSwipeListen.removeChatBox();
+                    return true;
+                }
+                break;
+        }
+        return super.onInterceptTouchEvent(ev);
+    }
+
+    public interface leftToRightSwipeListener {
+        void removeChatBox();
+    }
+
+    public void registerToSwipeEvents(leftToRightSwipeListener listener) {
+        this.leftToRightSwipeListen = listener;
+    }
+}

app/src/main/res/layout/main.xml

@@ -29,7 +29,7 @@
             android:layout_width="match_parent"
             android:layout_height="match_parent" />
 
-        <LinearLayout
+        <com.zulip.android.util.SwipeRemoveLinearLayout
             android:id="@+id/messageBoxContainer"
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
@@ -39,7 +39,7 @@
             android:background="@color/colorPrimary">
 
             <include layout="@layout/chatbox" />
-        </LinearLayout>
+        </com.zulip.android.util.SwipeRemoveLinearLayout>
 
         <android.support.design.widget.FloatingActionButton
             android:id="@+id/fab"