Question

我有一个显示WebView的片段，为了保留正在显示的网站，我保存了这样的状态：

@Override
public void onSaveInstanceState(Bundle outState) {
    super.onSaveInstanceState(outState);
    /*Saves the currently displayed webpage and the browser history*/
    webView.saveState(outState);        
}

然后我就这样恢复：

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {
    rootView = inflater.inflate(R.layout.fragment_page_detail,
            container, false);
    webView = (WebView) rootView.findViewById(R.id.page_detail_webview);

    progressBar = (ProgressBar) rootView.findViewById(R.id.op_progress);

    webView.setWebChromeClient(new WebChromeClient() {
        public void onProgressChanged(WebView view, int progress) {

            progressBar.setVisibility(View.VISIBLE);
            progressBar.setProgress(progress);
            if (progress == 100) {

                progressBar.setVisibility(View.GONE);
            }
        }
    });
    webView.setWebViewClient(new StockStreamWebViewClient());
    webView.getSettings().setBuiltInZoomControls(true);
    /*Restores the saved browser history if there is any*/
    if (savedInstanceState != null) {
        webView.restoreState(savedInstanceState);

    } else if (mItem != null) {
        webView.loadUrl(mItem.content);

    }
    return rootView;
}

要允许用户返回WebView，我在我的Activity中有这个代码：

@Override
public void onBackPressed() {

    if (!clientFragment.onBackPressed()) {
        super.onBackPressed();
    }
  }
}

我的片段中的代码：

public boolean onBackPressed() {
    if (webView != null && webView.canGoBack()) {
        webView.goBack();
        return true;
    } else {
        return false;
    }
}

当我旋转设备时，屏幕正确绘制，WebView恢复它的上一页，但是当我按下时，WebView为空。

为什么会这样？

谢谢，安克

Answer 1

所以我将这段代码添加到我的Activity中以保存片段的ID：

@Override
public void onSaveInstanceState(Bundle outState) {
    super.onSaveInstanceState(outState);
    if (clientFragment != null) {
        outState.putInt(CLIENT_FRAGMENT_ID, clientFragment.getId());
    }
}

此代码恢复对正确片段的引用：

if (savedInstanceState != null
            && savedInstanceState.containsKey(CLIENT_FRAGMENT_ID)) {
        clientFragment = (PageDetailFragment) getSupportFragmentManager()
                .findFragmentById(savedInstanceState.getInt(CLIENT_FRAGMENT_ID));
    }

PageDetailFragment是我的扩展片段。

谢谢，安克

WebView变得空无一人

1 个答案: