Java Code Examples for android.widget.ListAdapter#getView()

/**
 * 计算ListView的高度, 重置ListView的高度.
 * 
 * @param listView
 */
public static void setListViewHeightBasedOnChildren(ListView listView)
{
	ListAdapter listAdapter = listView.getAdapter();
	if (listAdapter == null)
	{
		return;
	}

	View listItem = null;
	int totalHeight = 0;
	for (int i = 0; i < listAdapter.getCount(); i++)
	{
		listItem = listAdapter.getView(i, null, listView);
		listItem.measure(0, 0);
		totalHeight += listItem.getMeasuredHeight();
	}

	ViewGroup.LayoutParams params = listView.getLayoutParams();
	params.height = totalHeight + (listView.getDividerHeight() * (listAdapter.getCount() - 1));
	listView.setLayoutParams(params);
}
 

/**
 * 手动设置listview的高度，包裹所有元素
 * @param listView
 */
public static void setListViewHeightBasedOnChildren(ListView listView) {  
       ListAdapter listAdapter = listView.getAdapter();   
       if (listAdapter == null) {  
           // pre-condition  
           return;  
       }  
 
       int totalHeight = 0;  
       for (int i = 0; i < listAdapter.getCount(); i++) {  
           View listItem = listAdapter.getView(i, null, listView);  
           listItem.measure(0, 0);  
           totalHeight += listItem.getMeasuredHeight();  
       }  
 
       ViewGroup.LayoutParams params = listView.getLayoutParams();  
       params.height = totalHeight + (listView.getDividerHeight() * (listAdapter.getCount() - 1));  
       listView.setLayoutParams(params);  
   }
 

@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
    super.onMeasure(widthMeasureSpec, heightMeasureSpec);
    int width = getMeasuredWidth();
    int height = 0;
    ListAdapter adapter = getAdapter();
    int count = adapter.getCount();
    for (int i = 0; i < count; i++) {
        View childView = adapter.getView(i, null, this);
        childView.measure(MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED),
                MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED));
        height += childView.getMeasuredHeight();
    }
    Rect bgPadding = new Rect();
    getBackground().getPadding(bgPadding);
    height += (count - 1) * getDividerHeight() + bgPadding.top + bgPadding.bottom;
    setMeasuredDimension(width, height);
}
 

/**
 * @param
 * @return int 返回类型
 * @Title getListViewHeightBasedOnChildren
 * @Description 得到children的高度
 */
public static int getListViewHeightBasedOnChildren(ListView listView) {
    ListAdapter listAdapter = listView.getAdapter();
    if (listAdapter == null) {
        // pre-condition
        return 0;
    }
    int totalHeight = 0;
    for (int i = 0; i < listAdapter.getCount(); i++) {
        View listItem = listAdapter.getView(i, null, listView);
        listItem.measure(0, 0);
        int itemHeight = listItem.getMeasuredHeight();
        System.out.println("itemHeight itemHeight:" + itemHeight);
        totalHeight += itemHeight;

    }

    int height = (int) (totalHeight
            + (listView.getDividerHeight() * (listAdapter.getCount() - 1)) + 0.5);

    return height;
}
 

/**
 * Get a View that displays the data at the specified position in the data
 * set.
 *
 * @param position    Position of the item whose data we want
 * @param convertView View to recycle, if not null
 * @param parent      ViewGroup containing the returned View
 */
public View getView(int position, View convertView, ViewGroup parent) {
    for (ListAdapter piece : pieces) {
        int size = piece.getCount();

        if (position < size) {

            return piece.getView(position, convertView, parent);
        }

        position -= size;
    }

    if (noItemsText != null) {
        TextView text = new TextView(parent.getContext());
        text.setText(noItemsText);
        return text;
    }

    return null;
}
 

public static void setListViewHeightBasedOnChildren(ListView listView) {
    ListAdapter listAdapter = listView.getAdapter();
    if (listAdapter == null) {
        // pre-condition
        return;
    }

    int totalHeight = 0;
    for (int i = 0; i < listAdapter.getCount(); i++) {
        View listItem = listAdapter.getView(i, null, listView);
        listItem.measure(0, 0);
        totalHeight += listItem.getMeasuredHeight();
    }

    ViewGroup.LayoutParams params = listView.getLayoutParams();
    params.height = totalHeight + (listView.getDividerHeight() * (listAdapter.getCount() - 1));
    listView.setLayoutParams(params);
}
 

/**
 * Get a View that displays the data at the specified
 * position in the data set.
 *
 * @param position
 *          Position of the item whose data we want
 * @param convertView
 *          View to recycle, if not null
 * @param parent
 *          ViewGroup containing the returned View
 */
@Override
public View getView(int position, View convertView, ViewGroup parent) {
    for (ListAdapter piece : getPieces()) {
        int size=piece.getCount();

        if (position < size) {

            return(piece.getView(position, convertView, parent));
        }

        position-=size;
    }

    return(null);
}
 

/**
 * Get a View that displays the data at the specified position in the data
 * set.
 *
 * @param position    Position of the item whose data we want
 * @param convertView View to recycle, if not null
 * @param parent      ViewGroup containing the returned View
 */
@Override
public View getView(int position, View convertView, ViewGroup parent) {
    for (ListAdapter piece : pieces) {
        int size = piece.getCount();

        if (position < size) {

            return (piece.getView(position, convertView, parent));
        }

        position -= size;
    }

    return (null);
}
 

/**
 * @author sunglasses
 * @param listView
 * @category 计算listview高度
 */
public static void setListViewHeightBasedOnChildren(ListView listView) {
	ListAdapter listAdapter = listView.getAdapter();
	if (listAdapter == null) {
		return;
	}

	int totalHeight = 0;
	for (int i = 0; i < listAdapter.getCount(); i++) {
		View listItem = listAdapter.getView(i, null, listView);
		listItem.measure(0, 0);
		totalHeight += listItem.getMeasuredHeight();
	}

	ViewGroup.LayoutParams params = listView.getLayoutParams();
	params.height = totalHeight
			+ (listView.getDividerHeight() * (listAdapter.getCount() - 1));
	listView.setLayoutParams(params);
}
 

/**
 * 重新計算GridView的高度
 *
 * @param gridView
 */
public static void setGridViewHeightBasedOnChildren(GridView gridView, int columns) {

    ListAdapter listAdapter = gridView.getAdapter();
    if (listAdapter == null) {
        // pre-condition
        return;
    }

    int totalHeight = 0;
    for (int i = 0; i < listAdapter.getCount() / columns; i++) {
        View listItem = listAdapter.getView(i, null, gridView);
        listItem.measure(0, 0);
        totalHeight += listItem.getMeasuredHeight();
    }

    ViewGroup.LayoutParams params = gridView.getLayoutParams();
    params.height = totalHeight + (listAdapter.getCount() - 1);
    gridView.setLayoutParams(params);
    gridView.requestLayout();
}
 

/**
 * This method adjusts the height of the given listView to match the combined height of all if its
 * children and the dividers between list items.  This is used to set the height of the mash step
 * list such that it does not scroll, since it is encompassed by a ScrollView.
 *
 * @param listView
 *         ListView to adjust.
 */
public static void setListViewHeightBasedOnChildren(ListView listView) {
  ListAdapter listAdapter = listView.getAdapter();
  if (listAdapter == null) {
    return;
  }

  int desiredWidth = View.MeasureSpec.makeMeasureSpec(listView.getWidth(), View.MeasureSpec.UNSPECIFIED);
  int totalHeight = listView.getPaddingTop() + listView.getPaddingBottom();
  View view = null;
  for (int i = 0; i < listAdapter.getCount(); i++) {
    view = listAdapter.getView(i, view, listView);

    view.measure(desiredWidth, View.MeasureSpec.UNSPECIFIED);

    if (i == 0) {
      view.setLayoutParams(new ViewGroup.LayoutParams(desiredWidth, ViewGroup.LayoutParams.WRAP_CONTENT));
      //totalHeight += view.getMeasuredHeight();
    }

    totalHeight += view.getMeasuredHeight();
  }
  ViewGroup.LayoutParams params = listView.getLayoutParams();
  params.height = totalHeight + (listView.getDividerHeight() * (listAdapter.getCount() - 1));
  listView.setLayoutParams(params);
  listView.requestLayout();
}
 

@Override
public void setAdapter(ListAdapter adapter) {

	if(isScroll)
	{
	
	int gridViewWidth = 0;
	int adapterCount = adapter.getCount();
	
	if(columnWidth == 0)
	{
		for(int i = 0 ; i< adapter.getCount();i++)
	    {
		View rowView = adapter.getView(i,null,null);
        measureView(rowView);
		gridViewWidth += rowView.getMeasuredWidth();
	    }
	}
	else
	{
		gridViewWidth += columnWidth*adapterCount;
	}

	if(isAutoSetNumColumns)
	{
		gridViewWidth += (this.getPaddingLeft()+ this.getPaddingRight());
		gridViewWidth += this.horizontalSpacing*(adapterCount-1);
		this.setNumColumns(adapterCount);
	}
	
	this.setLayoutParams(new LinearLayout.LayoutParams(gridViewWidth,LayoutParams.WRAP_CONTENT));

	}
	
	super.setAdapter(adapter);
}
 

@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
    super.onMeasure(widthMeasureSpec, heightMeasureSpec);

    int newHeight = 0;
    final int heightMode = MeasureSpec.getMode(heightMeasureSpec);
    int heightSize = MeasureSpec.getSize(heightMeasureSpec);
    if (heightMode != MeasureSpec.EXACTLY) {
        ListAdapter listAdapter = getAdapter();
        if (listAdapter != null && !listAdapter.isEmpty()) {
            int listPosition = 0;
            for (listPosition = 0; listPosition < listAdapter.getCount()
                    && listPosition < MAXIMUM_LIST_ITEMS_VIEWABLE; listPosition++) {
                View listItem = listAdapter.getView(listPosition, null, this);
                //now it will not throw a NPE if listItem is a ViewGroup instance
                if (listItem instanceof ViewGroup) {
                    listItem.setLayoutParams(mParams);
                }
                listItem.measure(widthMeasureSpec, heightMeasureSpec);
                newHeight += listItem.getMeasuredHeight();
            }
            newHeight += getDividerHeight() * listPosition;
        }
        if ((heightMode == MeasureSpec.AT_MOST) && (newHeight > heightSize)) {
            if (newHeight > heightSize) {
                newHeight = heightSize;
            }
        }
    } else {
        newHeight = getMeasuredHeight();
    }
    setMeasuredDimension(getMeasuredWidth(), newHeight);
}
 

public static void updateListViewHeight(ListView myListView) {
    ListAdapter myListAdapter = myListView.getAdapter();

    if (myListAdapter == null)
        return;

    // Get listView height
    int totalHeight = myListView.getPaddingTop() + myListView.getPaddingBottom();
    int adapterCount = myListAdapter.getCount();

    for (int i = 0; i < adapterCount; i++) {
        View listItem = myListAdapter.getView(i, null, myListView);

        if (listItem instanceof ViewGroup) {
            listItem.setLayoutParams(new ViewGroup.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT,
                                                                ViewGroup.LayoutParams.WRAP_CONTENT));
        }

        listItem.measure(0, 0);
        totalHeight += listItem.getMeasuredHeight();
    }

    // Change height of listView
    ViewGroup.LayoutParams paramsList = myListView.getLayoutParams();
    paramsList.height = totalHeight + (myListView.getDividerHeight() * (adapterCount - 1));
    myListView.setLayoutParams(paramsList);
}
 

public static int getAbsListViewHeight(AbsListView absListView, int lineNumber, int verticalSpace) {
    int totalHeight = 0;
    int w = MeasureSpec.makeMeasureSpec(0, 0);
    int h = MeasureSpec.makeMeasureSpec(0, 0);
    absListView.measure(w, h);
    ListAdapter mListAdapter = (ListAdapter) absListView.getAdapter();
    if (mListAdapter == null) {
        return 0;
    }
    int count = mListAdapter.getCount();
    View listItem;
    if (absListView instanceof ListView) {
        for (int i = 0; i < count; i++) {
            listItem = mListAdapter.getView(i, null, absListView);
            listItem.measure(w, h);
            totalHeight += listItem.getMeasuredHeight();
        }
        if (count == 0) {
            totalHeight = verticalSpace;
        } else {
            totalHeight += ((ListView) absListView).getDividerHeight() * (count - 1);
        }
    } else if (absListView instanceof GridView) {
        int remain = count % lineNumber;
        if (remain > 0) {
            remain = 1;
        }
        if (mListAdapter.getCount() == 0) {
            totalHeight = verticalSpace;
        } else {
            listItem = mListAdapter.getView(0, null, absListView);
            listItem.measure(w, h);
            int line = (count / lineNumber) + remain;
            totalHeight = (listItem.getMeasuredHeight() * line) + ((line - 1) * verticalSpace);
        }
    }
    return totalHeight;
}
 

private int getChildHeight(int position) {
    if (position == mSrcPos) {
        return 0;
    }

    View v = getChildAt(position - getFirstVisiblePosition());

    if (v != null) {
        // item is onscreen, therefore child height is valid,
        // hence the "true"
        return getChildHeight(position, v, false);
    } else {
        // item is offscreen
        // first check cache for child height at this position
        int childHeight = mChildHeightCache.get(position);
        if (childHeight != -1) {
            // Log.d("mobeta", "found child height in cache!");
            return childHeight;
        }

        final ListAdapter adapter = getAdapter();
        int type = adapter.getItemViewType(position);

        // There might be a better place for checking for the following
        final int typeCount = adapter.getViewTypeCount();
        if (typeCount != mSampleViewTypes.length) {
            mSampleViewTypes = new View[typeCount];
        }

        if (type >= 0) {
            if (mSampleViewTypes[type] == null) {
                v = adapter.getView(position, null, this);
                mSampleViewTypes[type] = v;
            } else {
                v = adapter.getView(position, mSampleViewTypes[type], this);
            }
        } else {
            // type is HEADER_OR_FOOTER or IGNORE
            v = adapter.getView(position, null, this);
        }

        // current child height is invalid, hence "true" below
        childHeight = getChildHeight(position, v, true);

        // cache it because this could have been expensive
        mChildHeightCache.add(position, childHeight);

        return childHeight;
    }
}
 

private int measureContentWidth() {
  ListAdapter adapter = getAdapter();
  TextInputLayout textInputLayout = findTextInputLayoutAncestor();
  if (adapter == null || textInputLayout == null) {
    return 0;
  }

  int width = 0;
  View itemView = null;
  int itemType = 0;
  final int widthMeasureSpec =
      MeasureSpec.makeMeasureSpec(getMeasuredWidth(), MeasureSpec.UNSPECIFIED);
  final int heightMeasureSpec =
      MeasureSpec.makeMeasureSpec(getMeasuredHeight(), MeasureSpec.UNSPECIFIED);

  // Cap the number of items that will be measured.
  int start = Math.max(0, modalListPopup.getSelectedItemPosition());
  final int end = Math.min(adapter.getCount(), start + MAX_ITEMS_MEASURED);
  start = Math.max(0, end - MAX_ITEMS_MEASURED);
  for (int i = start; i < end; i++) {
    final int positionType = adapter.getItemViewType(i);
    if (positionType != itemType) {
      itemType = positionType;
      itemView = null;
    }
    itemView = adapter.getView(i, itemView, textInputLayout);
    if (itemView.getLayoutParams() == null) {
      itemView.setLayoutParams(new LayoutParams(
          LayoutParams.WRAP_CONTENT,
          LayoutParams.WRAP_CONTENT));
    }
    itemView.measure(widthMeasureSpec, heightMeasureSpec);
    width = Math.max(width, itemView.getMeasuredWidth());
  }
  // Add background padding to measured width.
  Drawable background = modalListPopup.getBackground();
  if (background != null) {
    background.getPadding(tempRect);
    width += tempRect.left + tempRect.right;
  }
  // Add icon width to measured width.
  int iconWidth = textInputLayout.getEndIconView().getMeasuredWidth();
  width += iconWidth;

  return width;
}
 

private int getChildHeight(int position) {
    if (position == mSrcPos) {
        return 0;
    }

    View v = getChildAt(position - getFirstVisiblePosition());

    if (v != null) {
        // item is onscreen, therefore child height is valid,
        // hence the "true"
        return getChildHeight(position, v, false);
    } else {
        // item is offscreen
        // first check cache for child height at this position
        int childHeight = mChildHeightCache.get(position);
        if (childHeight != -1) {
            // Log.d("mobeta", "found child height in cache!");
            return childHeight;
        }

        final ListAdapter adapter = getAdapter();
        int type = adapter.getItemViewType(position);

        // There might be a better place for checking for the following
        final int typeCount = adapter.getViewTypeCount();
        if (typeCount != mSampleViewTypes.length) {
            mSampleViewTypes = new View[typeCount];
        }

        if (type >= 0) {
            if (mSampleViewTypes[type] == null) {
                v = adapter.getView(position, null, this);
                mSampleViewTypes[type] = v;
            } else {
                v = adapter.getView(position, mSampleViewTypes[type], this);
            }
        } else {
            // type is HEADER_OR_FOOTER or IGNORE
            v = adapter.getView(position, null, this);
        }

        // current child height is invalid, hence "true" below
        childHeight = getChildHeight(position, v, true);

        // cache it because this could have been expensive
        mChildHeightCache.add(position, childHeight);

        return childHeight;
    }
}
 

/**
 * 通过 ListView 绘制为 Bitmap
 * @param listView {@link ListView}
 * @param config   {@link Bitmap.Config}
 * @return {@link Bitmap}
 */
public static Bitmap snapshotByListView(final ListView listView, final Bitmap.Config config) {
    if (listView == null || config == null) return null;
    try {
        // Adapter
        ListAdapter listAdapter = listView.getAdapter();
        // Item 总条数
        int itemCount = listAdapter.getCount();
        // 没数据则直接跳过
        if (itemCount == 0) return null;
        // 高度
        int height = 0;
        // 获取子项间分隔符占用的高度
        int dividerHeight = listView.getDividerHeight();
        // View Bitmaps
        Bitmap[] bitmaps = new Bitmap[itemCount];

        // 循环绘制每个 Item 并保存 Bitmap
        for (int i = 0; i < itemCount; i++) {
            View childView = listAdapter.getView(i, null, listView);
            WidgetUtils.measureView(childView, listView.getWidth());
            bitmaps[i] = canvasBitmap(childView, config);
            height += childView.getMeasuredHeight();
        }
        // 追加子项间分隔符占用的高度
        height += (dividerHeight * (itemCount - 1));
        int width = listView.getMeasuredWidth();
        // 创建位图
        Bitmap bitmap = Bitmap.createBitmap(width, height, config);
        Canvas canvas = new Canvas(bitmap);
        canvas.drawColor(BACKGROUND_COLOR);
        // 累加高度
        int appendHeight = 0;
        for (int i = 0, len = bitmaps.length; i < len; i++) {
            Bitmap bmp = bitmaps[i];
            canvas.drawBitmap(bmp, 0, appendHeight, PAINT);
            appendHeight += (bmp.getHeight() + dividerHeight);
            // 释放资源
            bmp.recycle();
            bmp = null;
        }
        return bitmap;
    } catch (Exception e) {
        LogPrintUtils.eTag(TAG, e, "snapshotByListView");
    }
    return null;
}
 

/**
 * Measures the height of the given range of children (inclusive) and returns the height
 * with this ListView's padding and divider heights included. If maxHeight is provided, the
 * measuring will stop when the current height reaches maxHeight.
 *
 * @param widthMeasureSpec             The width measure spec to be given to a child's
 *                                     {@link View#measure(int, int)}.
 * @param startPosition                The position of the first child to be shown.
 * @param endPosition                  The (inclusive) position of the last child to be
 *                                     shown. Specify {@link #NO_POSITION} if the last child
 *                                     should be the last available child from the adapter.
 * @param maxHeight                    The maximum height that will be returned (if all the
 *                                     children don't fit in this value, this value will be
 *                                     returned).
 * @param disallowPartialChildPosition In general, whether the returned height should only
 *                                     contain entire children. This is more powerful--it is
 *                                     the first inclusive position at which partial
 *                                     children will not be allowed. Example: it looks nice
 *                                     to have at least 3 completely visible children, and
 *                                     in portrait this will most likely fit; but in
 *                                     landscape there could be times when even 2 children
 *                                     can not be completely shown, so a value of 2
 *                                     (remember, inclusive) would be good (assuming
 *                                     startPosition is 0).
 * @return The height of this ListView with the given children.
 */
public int measureHeightOfChildrenCompat(int widthMeasureSpec, int startPosition,
        int endPosition, final int maxHeight,
        int disallowPartialChildPosition) {
    final int paddingTop = getListPaddingTop();
    final int paddingBottom = getListPaddingBottom();
    final int paddingLeft = getListPaddingLeft();
    final int paddingRight = getListPaddingRight();
    final int reportedDividerHeight = getDividerHeight();
    final Drawable divider = getDivider();
    final ListAdapter adapter = getAdapter();
    if (adapter == null) {
        return paddingTop + paddingBottom;
    }
    // Include the padding of the list
    int returnedHeight = paddingTop + paddingBottom;
    final int dividerHeight = ((reportedDividerHeight > 0) && divider != null)
            ? reportedDividerHeight : 0;
    // The previous height value that was less than maxHeight and contained
    // no partial children
    int prevHeightWithoutPartialChild = 0;
    View child = null;
    int viewType = 0;
    int count = adapter.getCount();
    for (int i = 0; i < count; i++) {
        int newType = adapter.getItemViewType(i);
        if (newType != viewType) {
            child = null;
            viewType = newType;
        }
        child = adapter.getView(i, child, this);
        // Compute child height spec
        int heightMeasureSpec;
        ViewGroup.LayoutParams childLp = child.getLayoutParams();
        if (childLp == null) {
            childLp = generateDefaultLayoutParams();
            child.setLayoutParams(childLp);
        }
        if (childLp.height > 0) {
            heightMeasureSpec = MeasureSpec.makeMeasureSpec(childLp.height,
                    MeasureSpec.EXACTLY);
        } else {
            heightMeasureSpec = MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED);
        }
        child.measure(widthMeasureSpec, heightMeasureSpec);
        // Since this view was measured directly aginst the parent measure
        // spec, we must measure it again before reuse.
        child.forceLayout();
        if (i > 0) {
            // Count the divider for all but one child
            returnedHeight += dividerHeight;
        }
        returnedHeight += child.getMeasuredHeight();
        if (returnedHeight >= maxHeight) {
            // We went over, figure out which height to return.  If returnedHeight >
            // maxHeight, then the i'th position did not fit completely.
            return (disallowPartialChildPosition >= 0) // Disallowing is enabled (> -1)
                    && (i > disallowPartialChildPosition) // We've past the min pos
                    && (prevHeightWithoutPartialChild > 0) // We have a prev height
                    && (returnedHeight != maxHeight) // i'th child did not fit completely
                    ? prevHeightWithoutPartialChild
                    : maxHeight;
        }
        if ((disallowPartialChildPosition >= 0) && (i >= disallowPartialChildPosition)) {
            prevHeightWithoutPartialChild = returnedHeight;
        }
    }
    // At this point, we went through the range of children, and they each
    // completely fit, so return the returnedHeight
    return returnedHeight;
}