Android中GridView的書架效果實現

其實書架效果很好實現的，只要在自訂的GridView中的onDraw（）方法中計算下書架的位置矩形，然後draw出來就OK，個人認為比較簡單。

代碼如下：

 public class PlaybackFocusedGridView extends FocusedGridView {
Drawable mInterlayer = this.getResources().getDrawable(R.drawable.tv_playback_shelf);//書架圖片
Rect mMyDrawRect = new Rect();//書架的矩形位置

public PlaybackFocusedGridView(Context contxt, AttributeSet attrs, int defStyle) {
super(contxt, attrs, defStyle);
}

public PlaybackFocusedGridView(Context contxt, AttributeSet attrs) {
super(contxt, attrs);
}

public PlaybackFocusedGridView(Context contxt) {
super(contxt);
}

@Override
protected void onDraw(Canvas canvas) {
int count = getChildCount();
if (count > 0) {     //當有內容時
View v = getChildAt(0);//擷取螢幕的第一個可見的View

if (v != null) {
int gridview_height = this.getHeight();
int interlayerHeight = mInterlayer.getIntrinsicHeight();
int blockGapHeight = v.getHeight();
mMyDrawRect.left = 0;
mMyDrawRect.right = getWidth();
int initPos = v.getTop();

for (int i = initPos; i <= gridview_height; i += blockGapHeight) {
mMyDrawRect.top = i;
mMyDrawRect.bottom = mMyDrawRect.top + interlayerHeight;
mInterlayer.setBounds(mMyDrawRect);
mInterlayer.draw(canvas);//畫書架圖片
}
}

super.onDraw(canvas);//畫每一個Item
}
}
}