android 应用架构随笔六（Loading加载页面）

import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;import com.heima.googleplay.R;
import com.heima.googleplay.manager.ThreadManager;
import com.heima.googleplay.utils.UIUtils;import android.content.Context;
import android.util.AttributeSet;
import android.view.View;
import android.widget.FrameLayout;
/**
*
*
* ============================================================
**/
public abstract class LoadingPage extends FrameLayout {
//默认状态
private final int UN_LOADING = 1;
//加载状态
private final int LOADING = 2;
//加载失败状态
private final int ERROR = 3;
//加载成功。然后服务器没有返回数据
private final int EMPTY = 4;
//加载成功的状态
private final int SUCCESS = 5;
//用来记录某种状态
private int mState;
private View mLoadingView;
private View mErrorView;
private View mEmptyView; private View mSuccessView;
public LoadingPage(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
init();
} private void init() {
//首先赋值
mState = UN_LOADING; mLoadingView = createLoadingView(); if(null != mLoadingView){
addView(mLoadingView, new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT));
} mErrorView = createErrorView(); if(null != mErrorView){
addView(mErrorView,new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT));
} mEmptyView = createEmptyView(); if(null != mEmptyView ){
addView(mEmptyView, new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT));
}
//成功页面根据业务不同页面将不同，所以在此无法添加统一界面
//只能在主线程中展示出来
showSafePage(); }


private void showSafePage() {
UIUtils.runInMainThread(new Runnable() { @Override
public void run() {
showPage(); }
}); }

//三种页面已经添加到FrameLayout中，通过显示和隐藏来控制显示那个
protected void showPage() {
if(null != mLoadingView){
mLoadingView.setVisibility(mState == UN_LOADING || mState == LOADING ? View.VISIBLE : View.INVISIBLE);
} if(null != mErrorView){
mErrorView.setVisibility(mState == ERROR ? View.VISIBLE : View.INVISIBLE);
} if(null != mEmptyView){
mEmptyView.setVisibility(mState == EMPTY ? View.VISIBLE : View.INVISIBLE);
} if(null == mSuccessView && mState == SUCCESS ){
mSuccessView = createSuccessView();
addView(mSuccessView, new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT));
}
if(null != mSuccessView){
mSuccessView.setVisibility(mState == SUCCESS ? View.VISIBLE : View.INVISIBLE);
}
} public abstract View createSuccessView();//创建成功后显示的业务界面 private View createEmptyView() {
// TODO Auto-generated method stub
return UIUtils.inflate(R.layout.loading_page_empty);
} private View createErrorView() {
// TODO Auto-generated method stub
return UIUtils.inflate(R.layout.loading_page_error);
} private View createLoadingView() {
// TODO Auto-generated method stub
return UIUtils.inflate(R.layout.loading_page_loading);
} public LoadingPage(Context context, AttributeSet attrs) {
super(context, attrs);
init();
} public LoadingPage(Context context) {
super(context);
init();
}
// //加载失败状态
// private final int ERROR = 3;
// //加载成功。然后服务器没有返回数据
// private final int EMPTY = 4;
// //加载成功的状态
// private final int SUCCESS = 5;
public enum LoadResult{
ERROR(3),EMPTY(4),SUCCESS(5);
int value ;
LoadResult(int value){
this.value = value;
}
public int getValue() {
return value;
}
}

//利用线程池
private class LoadTask implements Runnable{ @Override
public void run() {
final LoadResult result = Load();
UIUtils.runInMainThread(new Runnable() { @Override
public void run() { mState = result.getValue(); showPage();
}
}); } } public void show() {
if(mState == ERROR || mState == EMPTY){
mState = UN_LOADING;
} if(mState == UN_LOADING){
mState = LOADING; LoadTask task = new LoadTask();
ThreadManager.getLongPool().execute(task);
// ExecutorService service = Executors.newFixedThreadPool(3);
// LoadTask task = new LoadTask();
// service.execute(task);
}
showSafePage();//加载完数据，在主线程中展示界面出来

}

//从服务器加载数据，返回加载状态（加载数据成功、失败？）
public abstract LoadResult Load() ;}

MainActivity