package com.ns.yc.ycstatelib;
import android.app.Activity;
import android.content.Context;
import android.os.Build;
import android.util.Log;
import android.util.SparseArray;
import android.view.View;
import android.view.ViewGroup;
import android.widget.FrameLayout;
import android.widget.FrameLayout.LayoutParams;
/**
* <pre>
* @author yangchong
* blog : https://github.com/yangchong211
* time : 2017/7/6
* desc : 自定义状态管理，用于list条目中
* revise: 借鉴大神齐翔开源库
* 参考链接：https://github.com/luckybilly/Gloading
* </pre>
*/
public class StateViewLayout {
public static final int STATUS_LOADING = 1;
public static final int STATUS_LOAD_SUCCESS = 2;
public static final int STATUS_LOAD_FAILED = 3;
public static final int STATUS_EMPTY_DATA = 4;
private static volatile StateViewLayout mDefault;
private Adapter mAdapter;
private static boolean DEBUG = false;
/**
* 提供显示当前加载状态的视图
*/
public interface Adapter {
/**
* get view for current status
* @param holder Holder
* @param convertView The old view to reuse, if possible.
* @param status current status
* @return status view to show. Maybe convertView for reuse.
* @see Holder
*/
View getView(Holder holder, View convertView, int status);
}
/**
* set debug mode or not
* @param debug true:debug mode, false:not debug mode
*/
public static void debug(boolean debug) {
DEBUG = debug;
}
/**
* 构造方法私有话，避免外部通过new进行初始化
*/
private StateViewLayout() { }
/**
* Create a new StateViewLayout different from the default one
* @param adapter another adapter different from the default one
* @return StateViewLayout
*/
public static StateViewLayout from(Adapter adapter) {
checkAdapter(adapter);
StateViewLayout stateViewLayout = new StateViewLayout();
stateViewLayout.mAdapter = adapter;
return stateViewLayout;
}
/**
* get default StateViewLayout object for global usage in whole app
* @return default StateViewLayout object
*/
public static StateViewLayout getDefault() {
if (mDefault == null) {
synchronized (StateViewLayout.class) {
if (mDefault == null) {
mDefault = new StateViewLayout();
}
}
}
return mDefault;
}
/**
* init the default loading status view creator ({@link Adapter})
* @param adapter adapter to create all status views
*/
public static void initDefault(Adapter adapter) {
checkAdapter(adapter);
getDefault().mAdapter = adapter;
}
/**
* StateViewLayout(loading status view) wrap the whole activity
* wrapper is android.R.id.content
* @param activity current activity object
* @return holder of StateViewLayout
*/
public Holder wrap(Activity activity) {
ViewGroup wrapper = activity.findViewById(android.R.id.content);
return new Holder(mAdapter, activity, wrapper);
}
/**
* StateViewLayout(loading status view) wrap the specific view.
* @param view view to be wrapped
* @return Holder
*/
public Holder wrap(View view) {
FrameLayout wrapper = new FrameLayout(view.getContext());
ViewGroup.LayoutParams lp = view.getLayoutParams();
if (lp != null) {
wrapper.setLayoutParams(lp);
}
if (view.getParent() != null) {
ViewGroup parent = (ViewGroup) view.getParent();
int index = parent.indexOfChild(view);
parent.removeView(view);
parent.addView(wrapper, index);
}
LayoutParams newLp = new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT);
wrapper.addView(view, newLp);
return new Holder(mAdapter, view.getContext(), wrapper);
}
/**
* 检查是否设置了自定义adapter，必须先初始化
* @param adapter adapter
*/
private static void checkAdapter(Adapter adapter){
if (adapter == null){
throw new NullPointerException("please set initDefault at first");
}
}
/**
* StateViewLayout holder<br>
* create by {@link StateViewLayout#wrap(Activity)} or {@link StateViewLayout#wrap(View)}<br>
* the core API for showing all status view
*/
public static class Holder {
private Adapter mAdapter;
private Context mContext;
private Runnable mRetryTask;
private View mCurStatusView;
private ViewGroup mWrapper;
private int curState;
private SparseArray<View> mStatusViews = new SparseArray<>(4);
private Object mData;
private Holder(Adapter adapter, Context context, ViewGroup wrapper) {
this.mAdapter = adapter;
this.mContext = context;
this.mWrapper = wrapper;
}
/**
* set retry task when user click the retry button in load failed page
* @param task when user click in load failed UI, run this task
* @return this
*/
public Holder withRetry(Runnable task) {
mRetryTask = task;
return this;
}
/**
* set extension data
* @param data extension data
* @return this
*/
public Holder withData(Object data) {
this.mData = data;
return this;
}
/** show UI for status: {@link #STATUS_LOADING} */
public void showLoading() {
showLoadingStatus(STATUS_LOADING);
}
/** show UI for status: {@link #STATUS_LOAD_SUCCESS} */
public void showLoadSuccess() {
showLoadingStatus(STATUS_LOAD_SUCCESS);
}
/** show UI for status: {@link #STATUS_LOAD_FAILED} */
public void showLoadFailed() {
showLoadingStatus(STATUS_LOAD_FAILED);
}
/** show UI for status: {@link #STATUS_EMPTY_DATA} */
public void showEmpty() {
showLoadingStatus(STATUS_EMPTY_DATA);
}
/**
* Show specific status UI
* @param status status
* @see #showLoading()
* @see #showLoadFailed()
* @see #showLoadSuccess()
* @see #showEmpty()
*/
public void showLoadingStatus(int status) {
if (curState == status || !validate()) {
return;
}
curState = status;
//first try to reuse status view
View convertView = mStatusViews.get(status);
if (convertView == null) {
//secondly try to reuse current status view
convertView = mCurStatusView;
}
try {
//call customer adapter to get UI for specific status. convertView can be reused
View view = mAdapter.getView(this, convertView, status);
if (view == null) {
printLog(mAdapter.getClass().getName() + ".getView returns null");
return;
}
if (view != mCurStatusView || mWrapper.indexOfChild(view) < 0) {
if (mCurStatusView != null) {
mWrapper.removeView(mCurStatusView);
}
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
view.setElevation(Float.MAX_VALUE);
}
mWrapper.addView(view);
ViewGroup.LayoutParams lp = view.getLayoutParams();
if (lp != null) {
lp.width = ViewGroup.LayoutParams.MATCH_PARENT;
lp.height = ViewGroup.LayoutParams.MATCH_PARENT;
}
} else if (mWrapper.indexOfChild(view) != mWrapper.getChildCount() - 1) {
// 确保加载状态视图在前面
view.bringToFront();
}
mCurStatusView = view;
mStatusViews.put(status, view);
} catch(Exception e) {
if (DEBUG) {
e.printStackTrace();
}
}
}
private boolean validate() {
if (mAdapter == null) {
printLog("StateViewLayout.Adapter is not specified.");
}
if (mContext == null) {
printLog("Context is null.");
}
if (mWrapper == null) {
printLog("The mWrapper of loading status view is null.");
}
return mAdapter != null && mContext != null && mWrapper != null;
}
public Context getContext() {
return mContext;
}
/**
* get wrapper
* @return container of gloading
*/
public ViewGroup getWrapper() {
return mWrapper;
}
/**
* get retry task
* @return retry task
*/
public Runnable getRetryTask() {
return mRetryTask;
}
/**
*
* get extension data
* @param <T> return type
* @return data
*/
public <T> T getData() {
try {
return (T) mData;
} catch(Exception e) {
if (DEBUG) {
e.printStackTrace();
}
}
return null;
}
}
private static void printLog(String msg) {
if (DEBUG) {
Log.e("StateViewLayout", msg);
}
}
}
