<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context=".MainActivity" > <TextView
android:id="@+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="当前网络：" /> <TextView
android:id="@+id/txt_show"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/hello_world" /> <Button
android:id="@+id/button1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Button" /> <Button
android:id="@+id/button2"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Button" /> <ImageView
android:id="@+id/imageView1"
android:layout_width="278dp"
android:layout_height="wrap_content"
android:layout_weight="1.14"
/> </LinearLayout>
java
package app.android.demo; import android.os.AsyncTask;
import android.os.Bundle;
import android.telephony.TelephonyManager;
import android.util.Log; import java.io.IOException;
import java.net.URL; import android.app.Activity;
import android.content.Context;
import android.graphics.drawable.Drawable;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.TextView;
import android.widget.Toast; public class MainActivity extends Activity
{
private ImageView mImageView = null ;
Button mButton1;
Button mButton2;
Button mButton3;
Button mButton4;
TextView mTextView;
TextView mTextView1;
ConnectivityManager connectMgr;
NetworkInfo[] networkInfo;
//The image url we are downloading from internet .
private final String IMAGE_URL1 = "http://a.hiphotos.baidu.com/image/pic/item/c2fdfc039245d688acbcd54ba0c27d1ed31b24a6.jpg" ;
private final String IMAGE_URL2 = "http://imgsrc.baidu.com/forum/w%3D580/sign=f9f1029647166d223877159c76230945/b69ad3f9d72a6059892764472c34349b023bbaca.jpg" ;
private final String IMAGE_URL3 = "http://static.open-open.com/lib/uploadImg/20130810/20130810175659_519.jpg" ;
private final String IMAGE_URL4 = "http://imgsrc.baidu.com/forum/w%3D580/sign=f9f1029647166d223877159c76230945/b69ad3f9d72a6059892764472c34349b023bbaca.jpg" ; @Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main); mImageView = (ImageView)this.findViewById(R.id.imageView1) ;
mButton1=(Button) findViewById(R.id.button1);
mButton2=(Button) findViewById(R.id.button2); mTextView=(TextView) findViewById(R.id.txt_show);
mTextView1=(TextView) findViewById(R.id.textView1); if (isNetworkAvailable(MainActivity.this))
{ mButton1.setOnClickListener(new Button1Lislen());
mButton2.setOnClickListener(new Button2Lislen());
mTextView1.setText("当前网络:=>可用");
Toast.makeText(getApplicationContext(), "当前有可用网络！", Toast.LENGTH_LONG).show();
}
else
{
mTextView1.setText("当前网络:=>不可用");
Toast.makeText(getApplicationContext(), "当前没有可用网络！", Toast.LENGTH_LONG).show();
} }
class Button1Lislen implements OnClickListener
{
@Override
public void onClick(View v)
{
new Thread(new Runnable(){
@Override
public void run() {
// TODO Auto-generated method stub
final Drawable drawable = loadImageFromNetwork(IMAGE_URL1); mImageView.post(new Runnable(){
@Override
public void run() {
// TODO Auto-generated method stub mImageView.setImageDrawable(drawable) ; }}) ;
} }).start() ; }
} private Drawable loadImageFromNetwork(String imageUrl)
{
Drawable drawable = null;
try {
drawable = Drawable.createFromStream(
new URL(imageUrl).openStream(), "image.gif");
} catch (IOException e) {
Log.d("test", e.getMessage());
}
if (drawable == null) {
Log.d("test", "null drawable");
} else {
Log.d("test", "not null drawable");
} return drawable ;
} class Button2Lislen implements OnClickListener
{
@Override
public void onClick(View v)
{
new DownloadImageTask().execute(IMAGE_URL2) ; } } private class DownloadImageTask extends AsyncTask<String, Void, Drawable>
{
/** The system calls this to perform work in a worker thread and
* delivers it the parameters given to AsyncTask.execute() */
protected Drawable doInBackground(String... urls) {
return loadImageFromNetwork(urls[0]);
} /** The system calls this to perform work in the UI thread and delivers
* the result from doInBackground() */
protected void onPostExecute(Drawable result) {
mImageView.setImageDrawable(result);
}
} //to see if these is a network
public boolean isNetworkAvailable(Activity activity)
{
Context context = activity.getApplicationContext();
// 获取手机所有连接管理对象（包括对wi-fi,net等连接的管理）
ConnectivityManager connectivityManager = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE); if (connectivityManager == null)
{
return false;
}
else
{
// 获取NetworkInfo对象
NetworkInfo[] networkInfo = connectivityManager.getAllNetworkInfo(); if (networkInfo != null && networkInfo.length > 0)
{
for (int i = 0; i < networkInfo.length; i++)
{
System.out.println(i + "===状态===" + networkInfo[i].getState());
System.out.println(i + "===类型===" + networkInfo[i].getTypeName());
mTextView.setText("===网络状态===>" + networkInfo[i].getState()+"\n"+
"===网络类型===>" + networkInfo[i].getTypeName());
//Toast.makeText(MainActivity.this, "===状态===" + networkInfo[i].getState()+networkInfo[i].getTypeName(), 3000).show();
// 判断当前网络状态是否为连接状态
if (networkInfo[i].getState() == NetworkInfo.State.CONNECTED)
{
// mTextView.setText("===网络状态===>" + networkInfo[i].getState()+"\n"+
// "===网络类型===>" + networkInfo[i].getTypeName());
return true;
}
// mTextView.setText("===状态===>" + networkInfo[i].getState()+"\n"+
// "===类型===>" + networkInfo[i].getTypeName());
}
}
}
return false;
} }
权限：
manifest
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="app.android.demo"
android:versionCode="1"
android:versionName="1.0" > <uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="18" />
<uses-permission android:name="android.permission.INTERNET"/>
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"></uses-permission>
<application
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name="app.android.demo.MainActivity"
android:label="@string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application> </manifest>
效果 :
