Android视图是否有类似于CSS类选择器的东西?是否有像 R.id 一样可用于多个视图的选项?我想隐藏某些视图组,而不考虑它们在布局结构中的位置。
我认为您需要遍历布局中的所有视图,查找所需的android:id。然后,您可以使用View setVisibility()更改可见性。您还可以使用View setTag() / getTag()而不是android:id来标记您想要处理的视图。例如,以下代码使用通用方法遍历布局:
// Get the top view in the layout.
final View root = getWindow().getDecorView().findViewById(android.R.id.content);
// Create a "view handler" that will hide a given view.
final ViewHandler setViewGone = new ViewHandler() {
public void process(View v) {
// Log.d("ViewHandler.process", v.getClass().toString());
v.setVisibility(View.GONE);
}
};
// Hide any view in the layout whose Id equals R.id.textView1.
findViewsById(root, R.id.textView1, setViewGone);
/**
* Simple "view handler" interface that we can pass into a Java method.
*/
public interface ViewHandler {
public void process(View v);
}
/**
* Recursively descends the layout hierarchy starting at the specified view. The viewHandler's
* process() method is invoked on any view that matches the specified Id.
*/
public static void findViewsById(View v, int id, ViewHandler viewHandler) {
if (v.getId() == id) {
viewHandler.process(v);
}
if (v instanceof ViewGroup) {
final ViewGroup vg = (ViewGroup) v;
for (int i = 0; i < vg.getChildCount(); i++) {
findViewsById(vg.getChildAt(i), id, viewHandler);
}
}
}
private static ArrayList<View> getViewsByTag(ViewGroup root, String tag){
ArrayList<View> views = new ArrayList<View>();
final int childCount = root.getChildCount();
for (int i = 0; i < childCount; i++) {
final View child = root.getChildAt(i);
if (child instanceof ViewGroup) {
views.addAll(getViewsByTag((ViewGroup) child, tag));
}
final Object tagObj = child.getTag();
if (tagObj != null && tagObj.equals(tag)) {
views.add(child);
}
}
return views;
}