问题描述
如何在ListView的顶部添加一个提示，如下拉刷新这是从android.support.v4包含在swipeRefreshLayout。
How do I add a hint on the top of a listView like "Pull down to refresh" which is contained in a swipeRefreshLayout from android.support.v4.
在下拉刷新的作品，但我想添加一个文本每当用户拉列表视图小幅回落。
The pull down to refresh works but I want to add a text whenever the user pulls the listview slightly down.
推荐答案
编辑2014年10月21日
EDIT 10/21/2014
如果您更新的支持-V4到最新版本（至少21.0.0），可以使用内置的负载指示！
If you update the support-v4 to the latest version (at least 21.0.0) you can use the built-in loading indicator!
我刚刚想出了一个简单而有效的解决方案。
I just came up with a simple, yet effective, solution.
这个想法是添加，生长高度时SwipeRefreshLayout孩子被推倒了一个自定义的ViewGroup。在这个ViewGroup中你会把你需要为你提示（TextViews，ImageViews，......）应有尽有。
The idea is to add a custom ViewGroup that grows its height when the SwipeRefreshLayout child gets pulled down. In this ViewGroup you will put everything you need for your hint (TextViews, ImageViews, ...).
我选择，因为它使更容易地定位你的暗示的元素来扩展RelativeLayout的。
I chose to extend a RelativeLayout because it makes easier to position your "hint" elements.
1）创建一个自定义部件如下：
1) Create a custom widget as follows:
public class SwipeRefreshHintLayout extends RelativeLayout {
public SwipeRefreshHintLayout(Context context) {
super(context);
}
public SwipeRefreshHintLayout(Context context, AttributeSet attrs) {
super(context, attrs);
}
public SwipeRefreshHintLayout(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
}
public void setSwipeLayoutTarget(final SwipeRefreshLayout swipeRefreshLayout) {
final View swipeTarget = swipeRefreshLayout.getChildAt(0);
if (swipeTarget == null) {
return;
}
swipeTarget.getViewTreeObserver().addOnPreDrawListener(new ViewTreeObserver.OnPreDrawListener() {
private Rect oldBounds = new Rect(), newBounds = new Rect();
@Override
public boolean onPreDraw() {
newBounds.set(swipeTarget.getLeft(), swipeRefreshLayout.getTop(), swipeTarget.getRight(), swipeTarget.getTop());
if (!oldBounds.equals(newBounds)){
getLayoutParams().height = newBounds.height();
requestLayout();
oldBounds.set(newBounds);
}
return true;
}
});
}
}
2）在您的片段或活动布局使用自定义的部件。
2) In your Fragment or Activity layout use this custom widget.
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<com.example.widget.SwipeRefreshHintLayout
android:id="@+id/swipe_hint"
android:layout_width="match_parent"
android:layout_height="0dp">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:text="@string/label_swipe_to_refresh"/>
<!-- Any other view positioned using RelativeLayout rules -->
</com.example.widget.SwipeRefreshHintLayout>
<android.support.v4.widget.SwipeRefreshLayout
android:id="@+id/swipe_container"
android:layout_width="match_parent"
android:layout_height="match_parent">
<ListView
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
</android.support.v4.widget.SwipeRefreshLayout>
</RelativeLayout>
3）然后，在你活动的onCreate（），或在您的片段onCreateView（），把这些行：
3) Then, in your Activity onCreate() or in your Fragment onCreateView(), put those lines:
mSwipeRefreshLayout = (SwipeRefreshLayout) rootView.findViewById(R.id.swipe_container);
mSwipeRefreshHintLayout = (SwipeRefreshHintLayout) rootView.findViewById(R.id.swipe_hint);
mSwipeRefreshHintLayout.setSwipeLayoutTarget(mSwipeRefreshLayout);
完成！
这篇关于添加文本提示到Android SwipeRefreshLayout的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！