android使用webview时按后退退出的问题

使用webview打包html5游戏，代码都好了，具体如下

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.ysmall.cc/mobile");
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，玩游戏，被电脑打败了，点击“更多游戏”去查看其他游戏，然后点返回键，问题来了，不是挖掘技术哪家强，是webview没有后退功能，没法退回首页，而是直接退出，android开发问题还真多啊，还好哥机灵，找资料呗！

终于找到问题了，

只需要重写activity的onKeyDown方法，在onKeyDown里后退即可

public boolean onKeyDown(int keyCode ,KeyEvent keyEvent){

if(keyCode==keyEvent.KEYCODE_BACK){//监听返回键，如果可以后退就后退

if(webView.canGoBack()){

webView.goBack();

return true;

}

}

return super.onKeyDown(keyCode, keyEvent);

}

全部代码贴出，免得以后忘记

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://gqhondatp.61tg.com/");

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);

}

}