增加启动页面

AndroidManifest.xml

@@ -12,25 +12,32 @@
 
     <uses-sdk
         android:minSdkVersion="8"
-        android:targetSdkVersion="21" />
+        android:targetSdkVersion="19" />
 
     <application
         android:name=".ZhihuApplication"
         android:allowBackup="true"
         android:icon="@drawable/ic_launcher"
         android:label="@string/app_name"
         android:theme="@style/Theme.Daily.AppTheme.Light" >
-        <activity
-            android:name=".activity.MainActivity"
+
+        <activity android:name=".activity.SplashActivity"
             android:alwaysRetainTaskState="true"
-            android:configChanges="orientation|keyboardHidden|screenSize"
-            android:label="@string/app_name" >
+            android:screenOrientation="portrait"
+            android:label="@string/app_name"
+            android:theme="@style/Theme.splash">
             <intent-filter>
                 <action android:name="android.intent.action.MAIN" />
 
                 <category android:name="android.intent.category.LAUNCHER" />
             </intent-filter>
         </activity>
+        <activity
+            android:name=".activity.MainActivity"
+            android:alwaysRetainTaskState="true"
+            android:configChanges="orientation|keyboardHidden|screenSize"
+            android:label="@string/app_name" >
+        </activity>
         <activity
             android:name=".activity.NewsDetailActivity"
             android:configChanges="orientation|keyboardHidden|screenSize"

res/anim/alpha.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<alpha xmlns:android="http://schemas.android.com/apk/res/android"
+    android:duration="2000"
+    android:fromAlpha="0.1"
+    android:toAlpha="1.0" />

res/layout/activity_splash.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent" >
+
+</LinearLayout>

res/values/styles.xml

@@ -75,4 +75,7 @@
         <item name="android:textColor">@color/ab_title_dark</item>
         <item name="android:textSize">18sp</item>
     </style>
+        <style name="Theme.splash" parent="@android:style/Theme.NoTitleBar.Fullscreen">
+        <item name="android:windowIsTranslucent">true</item>
+    </style>
 </resources>

src/com/cundong/izhihu/Constants.java

@@ -22,6 +22,9 @@ public static final class Url {
 
 		// 获取过往新闻
 		public static final String URLDEFORE = "http://news.at.zhihu.com/api/3/news/before/";
+
+		//获取启动页面的图片
+		public static final String URL_LAUNCHER = "http://news-at.zhihu.com/api/3/start-image/";
 	}
 
 	public static final int NEWS_LIST = 1;

src/com/cundong/izhihu/activity/SplashActivity.java

@@ -0,0 +1,264 @@
+package com.cundong.izhihu.activity;
+
+import java.io.File;
+import java.io.FileNotFoundException;
+import java.io.FileOutputStream;
+import java.io.IOException;
+
+import org.json.JSONException;
+import org.json.JSONObject;
+
+import android.annotation.SuppressLint;
+import android.app.Activity;
+import android.content.Context;
+import android.content.Intent;
+import android.graphics.Bitmap;
+import android.graphics.BitmapFactory;
+import android.graphics.drawable.BitmapDrawable;
+import android.graphics.drawable.Drawable;
+import android.os.Bundle;
+import android.os.Handler;
+import android.util.Log;
+import android.view.View;
+import android.view.animation.Animation;
+import android.view.animation.Animation.AnimationListener;
+import android.view.animation.AnimationUtils;
+
+import com.cundong.izhihu.Constants.Url;
+import com.cundong.izhihu.R;
+import com.cundong.izhihu.http.HttpClientUtils;
+import com.cundong.izhihu.task.MyAsyncTask;
+import com.cundong.izhihu.util.SDCardUtils;
+import com.nostra13.universalimageloader.core.ImageLoader;
+import com.nostra13.universalimageloader.core.assist.FailReason;
+import com.nostra13.universalimageloader.core.listener.SimpleImageLoadingListener;
+
+/**
+ * 启动页面
+ * 
+ * @author gonglei
+ * 
+ */
+public class SplashActivity extends Activity {
+
+	private static final String TAG = "SplashActivity";
+	private Context context;
+	private Handler mHandler = new Handler();
+	private String mImageUrl;
+	private View view;
+
+	@Override
+	protected void onCreate(Bundle savedInstanceState) {
+		// TODO Auto-generated method stub
+		super.onCreate(savedInstanceState);
+
+		view = View.inflate(this, R.layout.activity_splash, null);
+		setContentView(view);
+
+		context = this;
+		mImageUrl = SDCardUtils.getExternalCacheDir(context) + File.separator
+				+ "launcher_image";
+		initData();
+
+		Animation animation = AnimationUtils.loadAnimation(this, R.anim.alpha);
+		view.startAnimation(animation);
+
+		animation.setAnimationListener(new AnimationListener() {
+
+			@Override
+			public void onAnimationStart(Animation animation) {
+				// TODO Auto-generated method stub
+
+			}
+
+			@Override
+			public void onAnimationRepeat(Animation animation) {
+				// TODO Auto-generated method stub
+
+			}
+
+			@Override
+			public void onAnimationEnd(Animation animation) {
+				// TODO Auto-generated method stub
+				mHandler.postDelayed(new Runnable() {
+
+					@Override
+					public void run() {
+						// TODO Auto-generated method stub
+						goHome();
+					}
+				}, 500);
+			}
+		});
+	}
+
+	/**
+	 * 获取图片更新View
+	 */
+	@SuppressLint("NewApi")
+	private void initData() {
+		Bitmap bitmap = getImageFromLocal(mImageUrl);
+		if (bitmap != null) {
+			Drawable drawable = new BitmapDrawable(bitmap);
+			view.setBackground(drawable);
+			Log.d(TAG, "local image");
+		} else {
+			view.setBackground(getResources().getDrawable(
+					R.drawable.default_splash));
+			Log.d(TAG, "default");
+		}
+	}
+
+	/**
+	 * 获取手机分辨率拼接URL
+	 * 
+	 * @return
+	 */
+	private String initUrl() {
+		String splashUrl = null;
+		int width = getResources().getDisplayMetrics().widthPixels;
+		if (width == 480) {
+			splashUrl = Url.URL_LAUNCHER + "480*728";
+		} else if (width == 720) {
+			splashUrl = Url.URL_LAUNCHER + "720*1184";
+		} else if (width == 1080) {
+			splashUrl = Url.URL_LAUNCHER + "1080*1776";
+		}
+		Log.d(TAG, "width = " + width + ", url = " + splashUrl);
+		return splashUrl;
+	}
+
+	/**
+	 * 启动图片加载，跳转至主页
+	 */
+	private void goHome() {
+		new LoadImageTask().executeOnExecutor(MyAsyncTask.THREAD_POOL_EXECUTOR,
+				initUrl());
+		Intent intent = new Intent();
+		intent.setClass(this, MainActivity.class);
+		startActivity(intent);
+		finish();
+	}
+
+	/**
+	 * 图片下载的Task
+	 * 
+	 * @author gonglei
+	 * 
+	 */
+	private class LoadImageTask extends MyAsyncTask<String, String, String> {
+
+		@Override
+		protected String doInBackground(String... params) {
+			// TODO Auto-generated method stub
+			String result = null;
+			if (params[0] != null) {
+				try {
+					result = HttpClientUtils.get(SplashActivity.this,
+							params[0], null);
+				} catch (IOException e) {
+					// TODO Auto-generated catch block
+					e.printStackTrace();
+				} catch (Exception e) {
+					// TODO Auto-generated catch block
+					e.printStackTrace();
+				}
+			}
+			return result;
+		}
+
+		@Override
+		protected void onPostExecute(String result) {
+			// TODO Auto-generated method stub
+			Log.d(TAG, "result = " + result);
+			if (result == null) {
+				return;
+			}
+			JSONObject object;
+			String imageUrl = null;
+			try {
+				object = new JSONObject(result);
+				imageUrl = object.getString("img");
+				ImageLoader loader = ImageLoader.getInstance();
+				loader.loadImage(imageUrl, new SimpleImageLoadingListener() {
+
+					@Override
+					public void onLoadingComplete(String imageUri, View view,
+							Bitmap loadedImage) {
+						// TODO Auto-generated method stub
+						Log.d(TAG, "load complete");
+						saveImage(mImageUrl, loadedImage);
+						super.onLoadingComplete(imageUri, view, loadedImage);
+					}
+
+					@Override
+					public void onLoadingFailed(String imageUri, View view,
+							FailReason failReason) {
+						// TODO Auto-generated method stub
+						Log.d(TAG, "load failed");
+						super.onLoadingFailed(imageUri, view, failReason);
+					}
+
+				});
+			} catch (JSONException e) {
+				// TODO Auto-generated catch block
+				e.printStackTrace();
+			}
+			super.onPostExecute(result);
+		}
+
+	}
+
+	/**
+	 * 保存图片到本地
+	 * 
+	 * @param imagePath
+	 * @param bm
+	 */
+	private void saveImage(String imagePath, Bitmap bm) {
+
+		if (bm == null || imagePath == null || "".equals(imagePath)) {
+			return;
+		}
+
+		File f = new File(imagePath);
+		if (f.exists()) {
+			f.delete();
+		}
+		try {
+			File parentFile = f.getParentFile();
+			if (!parentFile.exists()) {
+				parentFile.mkdirs();
+			}
+			f.createNewFile();
+			FileOutputStream fos;
+			fos = new FileOutputStream(f);
+			bm.compress(Bitmap.CompressFormat.PNG, 100, fos);
+			fos.close();
+		} catch (FileNotFoundException e) {
+			f.delete();
+			e.printStackTrace();
+		} catch (IOException e) {
+			e.printStackTrace();
+			f.delete();
+		}
+
+	}
+
+	/**
+	 * 从本地获取图片
+	 * 
+	 * @param imagePath
+	 * @return
+	 */
+	private Bitmap getImageFromLocal(String imagePath) {
+		File file = new File(imagePath);
+		if (file.exists()) {
+			Bitmap bitmap = BitmapFactory.decodeFile(imagePath);
+			file.setLastModified(System.currentTimeMillis());
+			return bitmap;
+		}
+		return null;
+	}
+
+}