Aandroid-viewpager Source Code Analysis

 public boolean executekeyevent (keyevent event)  {         boolean handled = false;        if  ( Event.getaction ()  == keyevent.action_down)  {             switch  (Event.getkeycode ())  {                 case KeyEvent.KEYCODE_DPAD_LEFT: //  left.                      handled = arrowscroll (Focus_left); //                     break;                 case keyevent.keycode_dpad_right:                     handled =  Arrowscroll (focus_right); //  right .                     break;                 case KeyEvent.KEYCODE_TAB: //                      if   (BUILD.VERSION.SDK_INT >= 11)  {                         // The  focus finder had a bug handling focus_forward and focus_backward                          // before android 3.0. ignore the tab key on those  devices.                         if  (Keyeventcompat.hasnomodifiers (event))  {                              handled = arrowscroll (FOCUS_FORWARD);                          } else if  (Keyeventcompat.hasmodifiers (Event, keyevent.meta_shift_ ON))  {                             handled = arrowscroll (FOCUS_ backward);                          }                     }                     break;             }        }         return handled;    }

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Public boolean arrowscroll (int direction)  {         view currentfocused = findfocus (); //  Find Focus .           if  (currentfocused == this)  { //  The current focus is  viewpager.             currentFocused = null;         } else if  (currentfocused != null)  {  // page1, page2, page3... ...             boolean isChild = false;   //             for  (viewparent parent =  Currentfocused.getparent (); parent instanceof viewgroup;                     parent = parent.getparent ())  {                 if  (Parent == this)  { //  if the parent of the focus child control is viewpager.                     isChild = true;                     break;                 }             }             if  (!ischild)  {                 // This would cause the focus search down  below to fail in fun ways.                 final stringbuilder sb = new stringbuilder ();                 sb.append (CurrentFocused.getClass (). Getsimplename ());                 for  (Viewparent parent = currentfocused.getparent ();  parent instanceof  ViewGroup;                         parent = parent.getparent ())  {                      sb.append (" => "). Append (Parent.getclass (). Getsimplename ());                 }                 LOG.E (tag,  "Arrowscroll tried to find focus based on  non-child  " +                          "current focused view "   + sb.tostring ());                 currentFocused = null; //  is not a focus control within this Viewpager .             }        }

        boolean handled = false;     //  get   Next focus .  like: nextfocusright....         View nextfocused = focusfinder.getinstance (). Findnextfocus (this, currentfocused,                 direction);             if  (nextfocused != null  && nextfocused != currentfocused)  {             if  (Direction == view.focus_left)  { //  left .                 // If  There is nothing to the left, or this is causing us to                 // jump to the right,  then what we really want to do is page left.                 final int nextleft  = getchildrectinpagercoordinates (mtemprect, nextfocused) .left;                 final int currLeft =  Getchildrectinpagercoordinates (mtemprect, currentfocused) .left;                 //    if  (currentfocused ! = null && nextleft >= currleft)  {                     handled =  Pageleft ();                 } else {                      Handled = nextfocused.requestfocus (); //                 }             } else if  (direction == view.focus_right)  {                 // if there is nothing  to the right, or this is causing us to                 // jump to the  left, then what we really want to do is page right.                 final int nextleft =  Getchildrectinpagercoordinates (mtemprect, nextfocused) .left;                 final int currLeft =  Getchildrectinpagercoordinates (mtemprect, currentfocused) .left;                 if  (currentfocused != null & & nextleft <= currleft)  {                     handled = pageright ();  //   page to the right.                 }  else {                     handled = nExtfocused.requestfocus ();                 }            }         } else if  (direction == focus_left | |  direction == focus_backward)  {             // Trying to move left and nothing there; try  to page.            handled =  Pageleft ();        } else if  (direction ==  focus_right | |  direction == focus_forward)  {             // trying to move right and nothing there; try to  page.  &nbsP;         handled = pageright ();         }        if  (handled)  {             playsoundeffect ( Soundeffectconstants.getcontantforfocusdirection (direction));         }         return handled;    }

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Boolean pageright () {if (Madapter! = null && Mcuritem < (Madapter.getcount ()-1)) {Setcurren TItem (mcuritem+1, true);        return true;    } return false; }

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Aandroid-viewpager Source Code Analysis