清除图片缓存以及判断网络连接

	final File directory = new File(
				"/sdcard/Android/data/com.baway.test/cache/xBitmapCache");
		clear.setOnClickListener(new OnClickListener() {

			@Override
			public void onClick(View v) {
				if (directory != null && directory.exists()
						&& directory.isDirectory()) {
					for (File item : directory.listFiles()) {
						item.delete();
					}
					Toast.makeText(MainActivity.this, "yiqinghcu", 0).show();
				}
			}

		});

 判断网络连接的方法

	// 判断网络连接状态的方法
		ConnectivityManager conn = (ConnectivityManager) MainActivity.this
				.getSystemService(Context.CONNECTIVITY_SERVICE);
		if (conn != null) {
			NetworkInfo info = conn.getActiveNetworkInfo();
			if (info != null && info.isConnected()) {
				if (info.getState() == NetworkInfo.State.CONNECTED) {
					Toast.makeText(MainActivity.this, "网络连接正常", 0).show();
				}
			}
		}

 需要添加的权限

 <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>