Question

所以我想知道如何用空行填充ListView。 ListView是通过SQLite db填充的，所以说例如列表中只有3个项目我希望用空行填充屏幕的其余部分。这是我的意思的屏幕截图。是的，我知道它来自iPhone，但它证明了我的意思：

Answer 1

其他人已经躲过了，但我认为发布一个代码片段可能会有所帮助。如果有更好的技巧，如果我学到了什么，我会很乐意进行投票。

便宜的方法是在布局xml中添加额外的“行”。任何额外的行都将被屏幕截断。这可能会变得混乱：更高分辨率的屏幕可能需要您添加许多额外的TextView。由于它们被切断了，我想你可以添加任意多的东西。它看起来像这样：

<LinearLayout>

<ListView></ListView>

<TextView/>
<TextView/>
<TextView/>
...

</LinearLayout>

另一个选项是向ListView添加额外的行，如前所述。如果绑定到数组，请向数组添加额外的空行并适当地处理它。巧合的是，如果您使用光标，您可以使用MaxtrixCursor＆amp; MergeCursor，如本文所述：https://stackoverflow.com/a/16440093/103131

我最终使用了这些方法的组合。我尽力计算我想要添加到ListView的行数，但是我在注意方面出错并且在ListView下面有几个TextViews使它们全部聚集在一起。

Answer 2

当你创建数组时，它将被绑定到ListView，你只需要在数组的末尾添加几行空字符串。

Answer 3

just  make  sure     android:layout_height="match_parent"

<RelativeLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent" >
            <your.app.package.CustomListView
                android:id="@+id/editableTourListView"
                android:layout_width="match_parent"
                android:layout_height="match_parent" >
            </your.app.package.CustomListView>
        </RelativeLayout> 





    public class CustomListView extends ListView {
        private Paint mPaint = new Paint();
        private Paint mPaintBackground = new Paint();
        public CustomListView(Context context, AttributeSet attrs) {
            super(context, attrs);
            mPaint.setColor(Color.BLACK);
            mPaintBackground.setColor(Color.WHITE);
        }       
        @Override
        protected void dispatchDraw(Canvas canvas) {
            super.dispatchDraw(canvas);
            // ListView's height
            final int currentHeight = getMeasuredHeight();
            // this will let you know the status for the ListView, fitting/not
            // fitting content
            final int scrolledHeight = computeVerticalScrollRange();
            //        if (scrolledHeight >= currentHeight || scrolledHeight == 0) {
            // there is no need to draw something(for simplicity I assumed that
            // if the adapter has no items i wouldn't draw something on the
            // screen. If you still do want the lines then pick a decent value
            // to simulate a row's height and draw them until you hit the
            // ListView's getMeasuredHeight)
            //        } else {
            final View lastChild = getChildAt(getChildCount() - 1);
            if(lastChild==null) return;
            // values used to know where to start drawing lines
            final int lastChildBottom = lastChild.getBottom();
            // last child's height(use this to determine an appropriate value
            // for the row height)
            final int lastChildHeight = lastChild.getMeasuredHeight();
            // determine the number of lines required to fill the ListView
            final int nrOfLines = (currentHeight - lastChildBottom)
                    / lastChildHeight;
            // I used this to simulate a special color for the ListView's row background
            Rect r = new Rect(0, lastChildBottom, getMeasuredWidth(),
                    getMeasuredHeight());           
            canvas.drawRect(r, mPaintBackground);
            canvas.drawLine(0, lastChildBottom ,
                    getMeasuredWidth(), lastChildBottom, mPaint);
            for (int i = 0; i < nrOfLines; i++) {
                canvas.drawLine(0, lastChildBottom + (i + 1) * lastChildHeight,
                        getMeasuredWidth(), lastChildBottom + (i + 1)
                        * lastChildHeight, mPaint); 
            }
            return;
            //        }
    }
    }

Answer 4

使用listview下方的textview似乎给出了我想要的幻想。

Answer 5

@ kabir的解决方案有效。现在，如果你像我一样（想要在背景中有两种替代颜色，这是他重写的方法（或者说是编辑过的）

 @Override
protected void dispatchDraw(Canvas canvas) {
    super.dispatchDraw(canvas);

    int caseLastChildBottom = -1;
    int caselastChildHeight = -1;
    int caseNrOfLines = -1;

    //makes the colors follow the order (alternateColor1 - alternateColor2 - alternateColor1 - etc.)
    int plusIndex = 1;
    if (this.getChildCount() % 2 == 0)
        plusIndex = 0;

    // ListView's height
    final int currentHeight = getMeasuredHeight();

    // this will let you know the status for the ListView, fitting/not fitting content
    final int scrolledHeight = computeVerticalScrollRange();

    //empty listview (no item)
    if (scrolledHeight == 0) {
        //no childs exist so we take the top
        caseLastChildBottom = 0;
        //last child doesn't exist, so we set a default height (took the value in dp in the item row's height)
        caselastChildHeight = convertDpToPx(DEFAULT_CHILD_ROW_S_HEIGHT);
        // determine the number of lines required to fill the ListView
        caseNrOfLines = currentHeight / caselastChildHeight;
    }

    //there is a remaining gap to fill
    else {
        final View lastChild = getChildAt(getChildCount() - 1);
        if (lastChild == null) return;
        // values used to know where to start drawing lines
        caseLastChildBottom = lastChild.getBottom();
        // last child's height(use this to determine an appropriate value for the row height)
        caselastChildHeight = lastChild.getMeasuredHeight();
        // determine the number of lines required to fill the ListView
        caseNrOfLines = (currentHeight - caseLastChildBottom) / caselastChildHeight;
    }
    // values used to know where to start drawing lines
    final int lastChildBottom = caseLastChildBottom;
    // last child's height(use this to determine an appropriate value for the row height)
    final int lastChildHeight = caselastChildHeight;
    // determine the number of lines required to fill the ListView
    final int nrOfLines = caseNrOfLines;

    int i = 0;
    for (i = 0; i < nrOfLines; i++) {
        Rect r = new Rect(0, lastChildBottom + i * lastChildHeight, getMeasuredWidth(), lastChildBottom + (i + 1) * lastChildHeight);
        canvas.drawRect(r, (i + plusIndex) % 2 == 0 ? alternateColorView1 : alternateColorView2);
    }

    //is there a gap at the bottom of the list
    if(currentHeight - (nrOfLines *lastChildHeight) > 0){
        Rect r = new Rect(0, lastChildBottom + i * lastChildHeight,getMeasuredWidth(), currentHeight);
        canvas.drawRect(r, (i + plusIndex) % 2 == 0 ? alternateColorView1 : alternateColorView2);
    }
    return;
}

我忘记了这两种Paint颜色（就像@kabir声明颜色一样）：

    alternateColorView1.setColor(....);
    alternateColorView1.setStyle(Paint.Style.FILL);

    alternateColorView2.setColor(....);
    alternateColorView2.setStyle(Paint.Style.FILL);

在Android列表视图中显示空行

5 个答案: