Android硬件加速以及WebView的onPause,onResume,OnDestroy

package cn.testwebview;
import java.util.Timer;
import java.util.TimerTask;
import android.os.Bundle;
import android.view.View;
import android.view.ViewConfiguration;
import android.webkit.WebSettings;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import android.webkit.WebSettings.PluginState;
import android.app.Activity;
import android.graphics.Bitmap;
/**
* Demo描述:
* 1 硬件加速的实现
* 2 WebView的暂停/回复、销毁
*
* 参考资料:
* 1 http://stackoverflow.com/questions/5267639/how-to-safely-turn-webview-zooming-on-and-off-as-needed * 2 http://qianxuechao.blog.163.com/blog/static/91813499201292541451358/ *   Thank you very much
*/
public class MainActivity extends Activity {
private WebView mWebView;
private boolean isOnPause = false;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
hardwareAccelerate();
initWebView();
}

//硬件加速
private void hardwareAccelerate(){
if (this.getPhoneSDKInt() >= 14) {
getWindow().setFlags(0x1000000, 0x1000000);
}
}

//设置WebView
private void initWebView() {
mWebView = (WebView) findViewById(R.id.webView);
mWebView.setVerticalScrollBarEnabled(false);
mWebView.setHorizontalScrollBarEnabled(false);
mWebView.getSettings().setSupportZoom(true);
mWebView.getSettings().setBuiltInZoomControls(true);
mWebView.getSettings().setJavaScriptEnabled(true);

mWebView.getSettings().setDomStorageEnabled(true);
mWebView.getSettings().setPluginsEnabled(true);
mWebView.requestFocus();

//以下两句和硬件加速有关
mWebView.getSettings().setPluginState(PluginState.ON);
mWebView.getSettings().setAllowFileAccess(true);

mWebView.getSettings().setUseWideViewPort(true);
mWebView.getSettings().setLoadWithOverviewMode(true);
mWebView.getSettings().setCacheMode(WebSettings.LOAD_NO_CACHE);

mWebView.loadUrl("http://www.cdmetro.cn/");
mWebView.setWebViewClient(new TestWebViewClient());
}

/**
* 当Activity执行onPause()时让WebView执行pause
*/
@Override
protected void onPause() {
super.onPause();
try {
if (mWebView != null) {
mWebView.getClass().getMethod("onPause").invoke(mWebView, (Object[]) null);
isOnPause = true;
}

} catch (Exception e) {
e.printStackTrace();
}
}

/**
* 当Activity执行onResume()时让WebView执行resume
*/
@Override
protected void onResume() {
super.onResume();
try {
if (isOnPause) {
if (mWebView != null) {
mWebView.getClass().getMethod("onResume").invoke(mWebView, (Object[]) null);
}
isOnPause = false;
}
} catch (Exception e) {
e.printStackTrace();
}
}

/**
* 该处的处理尤为重要:
* 应该在内置缩放控件消失以后,再执行mWebView.destroy()
* 否则报错WindowLeaked
*/
@Override
protected void onDestroy() {
super.onDestroy();
if (mWebView != null) {
mWebView.getSettings().setBuiltInZoomControls(true);
mWebView.setVisibility(View.GONE);
long delayTime = ViewConfiguration.getZoomControlsTimeout();
new Timer().schedule(new TimerTask() {
@Override
public void run() {
mWebView.destroy();
mWebView = null;
}
}, delayTime);

}
isOnPause = false;
}

private class TestWebViewClient extends WebViewClient{
@Override
public void onPageStarted(WebView view, String url, Bitmap favicon) {
super.onPageStarted(view, url, favicon);
}
@Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
view.loadUrl(url);
return true;
}
@Override
public void onPageFinished(WebView view, String url) {
super.onPageFinished(view, url);

}
@Override
public void onReceivedError(WebView view, int errorCode,String description, String failingUrl) {
super.onReceivedError(view, errorCode, description, failingUrl);
}
}

public int getPhoneSDKInt() {
int version = 0;
try {
version = Integer.valueOf(android.os.Build.VERSION.SDK);
} catch (NumberFormatException e) {
e.printStackTrace();
}
return version;
}
}

<RelativeLayout
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"
>

<WebView
android:id="@+id/webView"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:text="@string/hello_world"
android:layout_centerInParent="true"
/>

</RelativeLayout>