說實話現在大部分人都不在用ListView了，不過說實話如果僅僅是普通的清單其實用哪個都無所謂的。
可能有人會說有好多第三方的下拉重新整理上拉加載的架構，但是我覺得吧，有些東西自己能實作的就還是用自己寫的好。
不羅嗦了，直接上代碼，注釋都已寫好
/**
* 繼承自SwipeRefreshLayout,進而實作滑動到底部時上拉加載更多的功能.
*/
public class RefreshLayout extends SwipeRefreshLayout implements
OnScrollListener {
/**
* 滑動到最下面時的上拉操作
*/
private int mTouchSlop;
/**
* listview執行個體
*/
private ListView mListView;
/**
* 上拉監聽器, 到了最底部的上拉加載操作
*/
private OnLoadListener mOnLoadListener;
/**
* ListView的加載中footer
*/
private View mListViewFooter;
/**
* 按下時的y坐标
*/
private int mYDown;
/**
* 擡起時的y坐标, 與mYDown一起用于滑動到底部時判斷是上拉還是下拉
*/
private int mLastY;
/**
* 是否在加載中 ( 上拉加載更多 )
*/
private boolean isLoading = false;
/**
* @param context
*/
public RefreshLayout(Context context) {
this(context, null);
}
@SuppressLint("InflateParams")
public RefreshLayout(Context context, AttributeSet attrs) {
super(context, attrs);
mTouchSlop = ViewConfiguration.get(context).getScaledTouchSlop();
mListViewFooter = LayoutInflater.from(context).inflate(
R.layout.listview_footer, null, false);
}
@Override
protected void onLayout(boolean changed, int left, int top, int right,
int bottom) {
super.onLayout(changed, left, top, right, bottom);
// 初始化ListView對象
if (mListView == null) {
getListView();
}
}
/**
* 擷取ListView對象
*/
private void getListView() {
int childs = getChildCount();
if (childs > 0) {
View childView = getChildAt(0);
if (childView instanceof ListView) {
mListView = (ListView) childView;
// 設定滾動監聽器給ListView, 使得滾動的情況下也可以自動加載
mListView.setOnScrollListener(this);
Log.d(VIEW_LOG_TAG, "### 找到listview");
}
}
}
/*
* (non-Javadoc)
*
* @see android.view.ViewGroup#dispatchTouchEvent(android.view.MotionEvent)
*/
@Override
public boolean dispatchTouchEvent(MotionEvent event) {
final int action = event.getAction();
switch (action) {
case MotionEvent.ACTION_DOWN:
// 按下
mYDown = (int) event.getRawY();
break;
case MotionEvent.ACTION_MOVE:
// 移動
mLastY = (int) event.getRawY();
break;
case MotionEvent.ACTION_UP:
// 擡起
if (canLoad()) {
loadData();
}
break;
default:
break;
}
return super.dispatchTouchEvent(event);
}
/**
* 是否可以加載更多, 條件是到了最底部, listview不在加載中, 且為上拉操作.
*
* @return
*/
private boolean canLoad() {
return isBottom() && !isLoading && isPullUp();
}
/**
* 判斷是否到了最底部
*/
private boolean isBottom() {
if (mListView != null && mListView.getAdapter() != null) {
return mListView.getLastVisiblePosition() == (mListView
.getAdapter().getCount() - 1);
}
return false;
}
/**
* 是否是上拉操作
*
* @return
*/
private boolean isPullUp() {
return (mYDown - mLastY) >= mTouchSlop;
}
/**
* 如果到了最底部,而且是上拉操作.那麼執行onLoad方法
*/
private void loadData() {
if (mOnLoadListener != null) {
// 設定狀态
setLoading(true);
//
mOnLoadListener.onLoad();
}
}
/**
* @param loading
*/
public void setLoading(boolean loading) {
isLoading = loading;
if (isLoading) {
mListView.addFooterView(mListViewFooter);
} else {
mListView.removeFooterView(mListViewFooter);
mYDown = 0;
mLastY = 0;
}
}
/**
* @param loadListener
*/
public void setOnLoadListener(OnLoadListener loadListener) {
mOnLoadListener = loadListener;
}
@Override
public void onScrollStateChanged(AbsListView view, int scrollState) {
}
@Override
public void onScroll(AbsListView view, int firstVisibleItem,
int visibleItemCount, int totalItemCount) {
// 滾動時到了最底部也可以加載更多
if (canLoad()) {
loadData();
}
}
/**
* 設定重新整理
*/
public static void setRefreshing(SwipeRefreshLayout refreshLayout,
boolean refreshing, boolean notify) {
Class<? extends SwipeRefreshLayout> refreshLayoutClass = refreshLayout
.getClass();
if (refreshLayoutClass != null) {
try {
Method setRefreshing = refreshLayoutClass.getDeclaredMethod(
"setRefreshing", boolean.class, boolean.class);
setRefreshing.setAccessible(true);
setRefreshing.invoke(refreshLayout, refreshing, notify);
} catch (NoSuchMethodException e) {
e.printStackTrace();
} catch (IllegalAccessException e) {
e.printStackTrace();
} catch (InvocationTargetException e) {
e.printStackTrace();
}
}
}
/**
* 加載更多的監聽器
*/
public static interface OnLoadListener {
public void onLoad();
}
} 複制
下面寫一下如何使用
- 在布局中使用自定義的RefreshLayout包裹ListView
<RefreshLayout
android:id="@+id/refreshLayout"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_weight="8">
<ListView
android:id="@+id/lv"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:divider="@null" />
</RefreshLayout> 複制
- 在Activity中調用refresh()方法，做RefreshLayout的監聽和顔色設定
private void refresh() {
refreshLayout.setColorSchemeResources(R.color.colorPrimary, R.color.colorAccent, R.color.colorAccent, R.color.colorPrimaryDark);
//下拉重新整理
refreshLayout.setOnRefreshListener(this);
//上拉加載
refreshLayout.setOnLoadListener(this);
} 複制
- 最後在實作的重新整理和上拉監聽中加refreshLayout.setLoading(false);使下拉和上拉的加載框消失
- 下拉重新整理加在onRefresh方法最後即可
@Override
public void onRefresh() {
//加在最後
refreshLayout.setRefreshing(false);
} 複制
- 上拉監聽需加在響應方法中即可
@Override
public void onLoad() {
page = ++page;
yNProgressDialog.show();
NetTool.getInstance().rxPostNet().subscribeOn(Schedulers.io())
.observeOn(AndroidSchedulers.mainThread())
.subscribe(new Consumer<>() {
@Override
public void accept(@NonNull Bean eBean) throws Exception {
NProgressDialog.dismiss();
if (eBean.getSuccess().equals("1")) {
refreshLayout.setLoading(false);
eAdapter.addData(eBean);
} else {
refreshLayout.setLoading(false);
refreshLayout.setOnLoadListener(null);
Toast.makeText(getApplicationContext().getApplicationContext(), eBean.getMsg().toString(), Toast.LENGTH_SHORT).show();
}
}
}, new Consumer<Throwable>() {
@Override
public void accept(@NonNull Throwable throwable) throws Exception {
refreshLayout.setLoading(false);
NProgressDialog.dismiss();
Toast.makeText(getApplicationContext().getApplicationContext(), "連接配接異常", Toast.LENGTH_SHORT).show();
}
});
} 複制