最近將要把美女圖片打包成安卓 

public class MainActivity extends ActionBarActivity {

    @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState);
         WebView webView=new WebView(this);
        webView.getSettings().setJavaScriptEnabled(true);//支持js webView.loadUrl("http://www.gg4493.cn/"
 
);//這裏的就會加載網址:http://www.gg4493/到webview中
        webView.setWebViewClient(new MyWebViewClient());


    }


    @Override public boolean onCreateOptionsMenu(Menu menu) { // Inflate the menu; this adds items to the action bar if it is present. getMenuInflater().inflate(R.menu.menu_main, menu); return true
 
;
    }

    @Override public boolean onOptionsItemSelected(MenuItem item) { // Handle action bar item clicks here. The action bar will  // automatically handle clicks on the Home/Up button, so long  // as you specify a parent activity in AndroidManifest.xml. int id = item.getItemId(); //noinspection SimplifiableIfStatement 
 
if (id == R.id.action_settings) { return true;
        } return super.onOptionsItemSelected(item);
    }
}

一切貌似很完美，玩遊戲，被電腦打敗了，點擊“更多遊戲”去查看其他遊戲，然後點返回鍵，問題來了，不是挖掘技術哪家強，是webview沒有後退功能，沒法退回首頁，而是直接退出，android開發問題還真多啊，還好哥機靈，找資料唄！

終於找到問題了，

只需要重寫activity的onKeyDown方法，在onKeyDown裏後退即可

public boolean onKeyDown(int keyCode ,KeyEvent keyEvent){
if(keyCode==keyEvent.KEYCODE_BACK){//監聽返回鍵，如果可以後退就後退
if(webView.canGoBack()){
webView.goBack();
return true;
}
}
return super.onKeyDown(keyCode, keyEvent);
}

全部代碼貼出，免得以後忘記

import android.app.Activity;
import android.os.Bundle;
import android.view.KeyEvent;
import android.view.Menu;
import android.webkit.WebSettings;
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);
init();
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}

private void init() {
webView = new WebView(this);
webView.loadUrl("http://www.gg4493.cn/");
WebSettings settings = webView.getSettings();
settings.setJavaScriptEnabled(true);
webView.setWebViewClient(new WebViewClient() {
@Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
view.loadUrl(url);
return true;
}
});
setContentView(webView);
}
public boolean onKeyDown(int keyCode ,KeyEvent keyEvent){
if(keyCode==keyEvent.KEYCODE_BACK){
if(webView.canGoBack()){
webView.goBack();
return true;
}
}
return super.onKeyDown(keyCode, keyEvent);
}
}

android使用webview時按後退退出的問題