MainActivity.java

package jp.hoge.webview;

import android.app.Activity;
import android.os.Bundle;
import android.view.KeyEvent;
import android.webkit.WebView;
import android.webkit.WebViewClient;

public class MainActivity extends Activity {

    private WebView webView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        webView = (WebView) findViewById(R.id.webview);
        webView.setWebViewClient(new WebViewClient());
        webView.loadUrl("http://hoge.jp/");
        webView.getSettings().setJavaScriptEnabled(true);
    }


    public boolean onKeyDown(int keyCode, KeyEvent event) {
        // 端末の戻るボタンでブラウザバック
        if(keyCode == KeyEvent.KEYCODE_BACK && webView.canGoBack()) {
            webView.goBack();
            return true;
        }
        return super.onKeyDown(keyCode,  event);
    }

}