要按照您的要求进行操作,您需要负责GridView 的画布,将被触摸的列分开,并为拖动、甩动等进行自己的绘图。一旦移动完成,您将需要通过GridView对栏目中的视图进行调整,保持簿记平顺。我会查看讨论视图移动的在线文档。 "Dragging and Scaling" 将是一个不错的起点。
这种方法会有一些“陷阱”。如果您只是想将其作为一种技术来学习,那么我会说您的方法还可以。如果您想完成效果并按设计使用GridView 的底层实现(滚动、边缘效果、弹跳等),我建议另一种方法。
您可以通过并排对齐三个 1x3 网格视图来构建 GridView 的外观,而不是单个 3x3 GridView。 (实际上,网格视图将是 1x11 以适应垂直幻灯片的最大范围。)如果编码为支持多个网格视图,则每个网格视图都可以由单个适配器支持。由于每一列都有自己的网格视图,因此每一列都可以独立滑动。
这种方法的优点是您可以在不扭曲底层GridView 类的情况下获得您想要的效果。同样的方法可以使用您现有的使用按钮的方法。
我很好奇如何实施我的建议。下面是一个示例应用程序,上面解释了三个GridView 实现以及相同的视频。
MainActivity.java
public class MainActivity extends AppCompatActivity
implements GridView.OnScrollListener {
@Override
public void onCreate(Bundle savedInstanceState) {
final GridViewAdapter adapter = new GridViewAdapter();
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
setupGridView(R.id.gridview0, adapter);
setupGridView(R.id.gridview1, adapter);
setupGridView(R.id.gridview2, adapter);
}
private void setupGridView(int id, GridViewAdapter adapter) {
final GridView gridview = (GridView) findViewById(id);
gridview.setAdapter(adapter);
// Temporary scroll listener until initial scroll to position is done.
// This hides the initial movement of the grid cells.
gridview.setOnScrollListener(new AbsListView.OnScrollListener() {
@Override
public void onScrollStateChanged(AbsListView view, int scrollState) {
if (scrollState == AbsListView.OnScrollListener.SCROLL_STATE_IDLE) {
gridview.setOnScrollListener(MainActivity.this);
}
}
@Override
public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) {
// Do nothing
}
});
gridview.smoothScrollToPositionFromTop(2, 0);
}
@Override
public void onScrollStateChanged(AbsListView view, int scrollState) {
if (scrollState == AbsListView.OnScrollListener.SCROLL_STATE_IDLE) {
final int top = view.getChildAt(0).getTop();
final int itemHeight = ((GridViewAdapter) (view.getAdapter())).getItemHeight();
// top <= 0
if (top > -(itemHeight / 2)) {
// Less than 1/2 cell height out of place - shift down.
view.scrollListBy(top);
} else {
// Shift up
view.scrollListBy(top + itemHeight);
}
}
}
@Override
public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) {
// Do nothing
}
@SuppressWarnings("unused")
private static final String TAG = "MainActivity";
}
GridViewAdapter.java
class GridViewAdapter extends BaseAdapter {
GridViewAdapter() {
}
@Override
public int getCount() {
return mStrings.length / GRID_COLUMN_COUNT;
}
@Override
public Object getItem(int position) {
return null;
}
@Override
public long getItemId(int position) {
return 0;
}
// create a new TextView for each item referenced by the Adapter
@Override
public View getView(int position, View convertView, ViewGroup parent) {
TextView textView;
final int column = Integer.parseInt((String) parent.getTag());
if (convertView == null) {
// if it's not recycled, initialize some attributes
textView = new TextView(parent.getContext());
GridView.LayoutParams params =
new GridView.LayoutParams(GRID_ITEM_WIDTH, GRID_ITEM_HEIGHT);
textView.setLayoutParams(params);
textView.setTextSize(TypedValue.COMPLEX_UNIT_SP, 20);
textView.setGravity(Gravity.CENTER);
} else {
// Recycle the view but keep old attributes since they don't change.
textView = (TextView) convertView;
}
textView.setText(mStrings[position * GRID_COLUMN_COUNT + column]);
return textView;
}
int getItemHeight() {
return GRID_ITEM_HEIGHT;
}
private final static String[] mStrings = {
"", "", "",
"", "", "",
"", "", "",
"", "", "",
"1", "2", "3",
"4", "5", "6",
"7", "8", "9",
"", "", "",
"", "", "",
"", "", "",
"", "", ""
};
private static final int GRID_ITEM_HEIGHT = 150; // in pixels
private static final int GRID_ITEM_WIDTH = 150; // in pixels
private static final int GRID_COLUMN_COUNT = 3;
}
activity_main.java
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/linearLayout"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:orientation="horizontal">
<!-- Sorry for the dimensions in pixels. It just makes everything easier.
Non-pixel dimensions (dp) should be used here and accommodations made in the code. -->
<GridView xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/gridview0"
android:layout_width="150px"
android:layout_height="1050px"
android:columnWidth="150px"
android:horizontalSpacing="0dp"
android:numColumns="1"
android:scrollbars="none"
android:tag="0"
android:verticalSpacing="0dp" />
<GridView xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/gridview1"
android:layout_width="150px"
android:layout_height="1050px"
android:columnWidth="150px"
android:horizontalSpacing="0dp"
android:numColumns="1"
android:scrollbars="none"
android:tag="1"
android:verticalSpacing="0dp" />
<GridView xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/gridview2"
android:layout_width="150px"
android:layout_height="1050px"
android:columnWidth="150px"
android:horizontalSpacing="0dp"
android:numColumns="1"
android:scrollbars="none"
android:tag="2"
android:verticalSpacing="0dp" />
</LinearLayout>