Splash Screen加载网络图片实现欢迎页的两种方法

Splash Screen加载网络图片可以用两种方法，一般用在开启app时显示公司logo，广告，或者欢迎页，介绍两种方法来处理：异步加载和子线程处理。第一种是异步加载的方法在onCreate中设置/**异步加载*/new FetchDataTask().execute(url);然后编写异步加载的方法/**异步加载*/public class FetchDataTask extends AsyncTask<String,Void,Bitmap>{        //执行前调用        @Override        protected void onPreExecute() {            super.onPreExecute();        }        //执行后台任务        @Override        protected Bitmap doInBackground(String... strings) {            Bitmap bitmap=null;            try {                bitmap= Utils.getBitmap(url);            } catch (Exception e) {                e.printStackTrace();            }            return bitmap;        }        //任务完成时调用        @Override        protected void onPostExecute(Bitmap bitmap) {            super.onPostExecute(bitmap);            imageView.setImageBitmap(bitmap);        }    }完整代码package com.dxsport;import com.dxsport.common.Utils;import android.app.Activity;import android.content.Intent;import android.graphics.Bitmap;import android.os.AsyncTask;import android.os.Bundle;import android.os.Handler;import android.os.Message;import android.view.Window;import android.view.WindowManager;import android.widget.ImageView;public class SplashScreenActivity extends Activity {private String url = "http://tupian.enterdesk.com/2015/saraxuss/04/17/gou/1/3.jpg";private ImageView imageView;Bitmap bitmap = null;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);this.requestWindowFeature(Window.FEATURE_NO_TITLE);//去掉标题栏 this.getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);//去掉信息栏setContentView(R.layout.splash_screen);imageView = (ImageView) findViewById(R.id.adImage);/**异步加载*/new FetchDataTask().execute(url);new Handler().postDelayed(new Runnable() {   @Override   public void run() {   Intent  i = new Intent(SplashScreenActivity.this, MainActivity.class); startActivity(i); SplashScreenActivity.this.finish();  } },3000); }/**异步加载*/public class FetchDataTask extends AsyncTask<String,Void,Bitmap>{        //执行前调用        @Override        protected void onPreExecute() {            super.onPreExecute();        }        //执行后台任务        @Override        protected Bitmap doInBackground(String... strings) {            Bitmap bitmap=null;            try {                bitmap= Utils.getBitmap(url);            } catch (Exception e) {                e.printStackTrace();            }            return bitmap;        }        //任务完成时调用        @Override        protected void onPostExecute(Bitmap bitmap) {            super.onPostExecute(bitmap);            imageView.setImageBitmap(bitmap);        }    }}第二种是添加子线程的方法在onCreate中设置// 开启一个子线程，进行网络操作，等待有返回结果，使用handler通知UI  new Thread(networkTask).start();然后编写子线程方法Handler handler = new Handler() {  @Override  public void handleMessage(Message msg) {  super.handleMessage(msg);  Bundle data = msg.getData();  Bitmap bitmap = data.getParcelable("bitmap");// UI界面的更新等相关操作  imageView.setImageBitmap(bitmap);}  };  /**  * 网络操作相关的子线程  */  Runnable networkTask = new Runnable() {    @Override  public void run() {  // 在这里进行 http request.网络请求相关操作  Message msg = new Message();  Bundle data = new Bundle();  Bitmap bitmap = Utils.getBitmap(url);data.putParcelable("bitmap", bitmap);msg.setData(data);  handler.sendMessage(msg);  }  };  完整代码package com.dxsport;import com.dxsport.common.Utils;import android.app.Activity;import android.content.Intent;import android.graphics.Bitmap;import android.os.AsyncTask;import android.os.Bundle;import android.os.Handler;import android.os.Message;import android.view.Window;import android.view.WindowManager;import android.widget.ImageView;public class SplashScreenActivity extends Activity {private String url = "http://tupian.enterdesk.com/2015/saraxuss/04/17/gou/1/3.jpg";private ImageView imageView;Bitmap bitmap = null;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);this.requestWindowFeature(Window.FEATURE_NO_TITLE);//去掉标题栏 this.getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);//去掉信息栏setContentView(R.layout.splash_screen);imageView = (ImageView) findViewById(R.id.adImage);// 开启一个子线程，进行网络操作，等待有返回结果，使用handler通知UI  new Thread(networkTask).start();  new Handler().postDelayed(new Runnable() {   @Override   public void run() {   Intent  i = new Intent(SplashScreenActivity.this, MainActivity.class); startActivity(i); SplashScreenActivity.this.finish();  } },3000); }Handler handler = new Handler() {  @Override  public void handleMessage(Message msg) {  super.handleMessage(msg);  Bundle data = msg.getData();  Bitmap bitmap = data.getParcelable("bitmap");// UI界面的更新等相关操作  imageView.setImageBitmap(bitmap);}  };  /**  * 网络操作相关的子线程  */  Runnable networkTask = new Runnable() {    @Override  public void run() {  // 在这里进行 http request.网络请求相关操作  Message msg = new Message();  Bundle data = new Bundle();  Bitmap bitmap = Utils.getBitmap(url);data.putParcelable("bitmap", bitmap);msg.setData(data);  handler.sendMessage(msg);  }  };  }Utils 类package com.dxsport.common;import java.io.InputStream;import java.net.HttpURLConnection;import java.net.URL;import android.graphics.Bitmap;import android.graphics.BitmapFactory;public class Utils { /**通过传入的图片地址，获取图片*/public static Bitmap getBitmap(String url){Bitmap bitmap = null;try {            HttpURLConnection connection= (HttpURLConnection) (new URL(url)).openConnection();            InputStream is=connection.getInputStream();            bitmap= BitmapFactory.decodeStream(is);        } catch (Exception e) {            e.printStackTrace();        }return bitmap;}}splash_screen.xml<?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"    android:orientation="vertical" >    <ImageView        android:id="@+id/adImage"        android:layout_width="wrap_content"        android:layout_height="wrap_content"/></LinearLayout>