src/com/owncloud/android/ui/ExtendedListView.java

   1 package com.owncloud.android.ui;
   2
   3 import android.content.Context;
   4 import android.graphics.Canvas;
   5 import android.util.AttributeSet;
   6 import android.widget.ListView;
   7
   8 /**
   9  * ListView allowing to specify the position of an item that should be centered in the visible area, if possible.
  10  *
  11  * The cleanest way I found to overcome the problem due to getHeight() returns 0 until the view is really drawn.
  12  *
  13  * @author David A. Velasco
  14  */
  15 public class ExtendedListView extends ListView {
  16
  17     private int mPositionToSetAndCenter;
  18
  19     public ExtendedListView(Context context) {
  20         super(context);
  21     }
  22
  23     public ExtendedListView(Context context, AttributeSet attrs) {
  24         super(context, attrs);
  25     }
  26
  27     public ExtendedListView(Context context, AttributeSet attrs, int defStyle) {
  28         super(context, attrs, defStyle);
  29     }
  30
  31     /**
  32      * {@inheritDoc}
  33      *
  34      *
  35      */
  36     @Override
  37     protected void onDraw (Canvas canvas) {
  38         super.onDraw(canvas);
  39         if (mPositionToSetAndCenter > 0) {
  40             this.setSelectionFromTop(mPositionToSetAndCenter, getHeight() / 2);
  41             mPositionToSetAndCenter = 0;
  42         }
  43     }
  44
  45     /**
  46      * Public method to set the position of the item that should be centered in the visible area of the view.
  47      *
  48      * The position is saved here and checked in onDraw().
  49      *
  50      * @param position         Position (in the list of items) of the item to center in the visible area.
  51      */
  52     public void setAndCenterSelection(int position) {
  53         mPositionToSetAndCenter = position;
  54     }
  55 }