Android ICS中的脱节WebView绘图

Android ICS中的脱节WebView绘图,android,android-webview,android-4.0-ice-cream-sandwich,Android,Android Webview,Android 4.0 Ice Cream Sandwich,我正在制作一个应用程序,它有一个与其他元素内联的Webview,嵌套在ScrollView中。我注意到,在ICS中,在Galaxy Nexus设备上进行测试时,当页面被甩出时,WebView似乎与显示的其他元素脱节,导致WebView看起来是浮动的,因为在绘图时有几毫秒的延迟。这在2.x版本的Android中不会发生(未在3.x上测试)。这是浮动效果的视频(如果设置为1080p全屏,您可以清楚地看到) 有人能提出为什么会发生这种情况,或者解决办法吗 我在下面设置了一个测试项目来演示: packa

我正在制作一个应用程序,它有一个与其他元素内联的Webview,嵌套在ScrollView中。我注意到,在ICS中,在Galaxy Nexus设备上进行测试时,当页面被甩出时,WebView似乎与显示的其他元素脱节,导致WebView看起来是浮动的,因为在绘图时有几毫秒的延迟。这在2.x版本的Android中不会发生(未在3.x上测试)。这是浮动效果的视频(如果设置为1080p全屏,您可以清楚地看到)

有人能提出为什么会发生这种情况,或者解决办法吗

我在下面设置了一个测试项目来演示:

package com.martynhaigh.floating_web_view;

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.webkit.WebView;
import android.widget.FrameLayout;
import android.widget.LinearLayout;
import android.widget.ScrollView;
import android.widget.TextView;

public class FloatingWebViewTestActivity extends FragmentActivity {
    public final int viewId = 0x12345678;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        FrameLayout.LayoutParams lp = new FrameLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT);
        FrameLayout frame = new FrameLayout(this);
        frame.setId(viewId);
        setContentView(frame, lp);

        FloatingWebViewICSFragment fragment = new FloatingWebViewICSFragment();
        getSupportFragmentManager().beginTransaction().add(viewId, fragment).commit();
    }

    public static class FloatingWebViewICSFragment extends Fragment {

        private final String htmlBody = "<html><body><p style=\"font-size:1.5em\">This is a test document. This is a test document. This is a test document. This is a test document. This is a test document. This is a test document. This is a test document. This is a test document. This is a test document. This is a test document. This is a test document. This is a test document. This is a test document. This is a test document. This is a test document. This is a test document. This is a test document. This is a test document. This is a test document. This is a test document. This is a test document. This is a test document. This is a test document. This is a test document. This is a test document. This is a test document. This is a test document. This is a test document. </body></html>";

        @Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
        }

        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {

            TextView textView = new TextView(getActivity().getApplicationContext());
            textView.setText("Test Activity");

            WebView webView = new WebView(getActivity().getApplicationContext());
            webView.loadDataWithBaseURL("file:///android_asset/", htmlBody, "text/html", "UTF-8", "about:blank");
            webView.setScrollBarStyle(View.SCROLLBARS_INSIDE_OVERLAY);
            webView.setScrollContainer(false);

            TextView textView2 = new TextView(getActivity().getApplicationContext());
            textView2.setText("Test Activity");

            FrameLayout.LayoutParams lp = new FrameLayout.LayoutParams(ViewGroup.LayoutParams.FILL_PARENT, ViewGroup.LayoutParams.FILL_PARENT);

            LinearLayout layout = new LinearLayout(getActivity().getApplicationContext());
            layout.setLayoutParams(lp);
            layout.setOrientation(LinearLayout.VERTICAL);

            layout.addView(textView);
            layout.addView(webView);
            layout.addView(textView2);

            ScrollView scrollView = new ScrollView(getActivity().getApplicationContext());
            scrollView.setLayoutParams(lp);
            scrollView.addView(layout);

            return scrollView;
        }

    }
}
package com.martynhaigh.floating_web_视图;
导入android.os.Bundle;
导入android.support.v4.app.Fragment;
导入android.support.v4.app.FragmentActivity;
导入android.view.LayoutInflater;
导入android.view.view;
导入android.view.ViewGroup;
导入android.webkit.WebView;
导入android.widget.FrameLayout;
导入android.widget.LinearLayout;
导入android.widget.ScrollView;
导入android.widget.TextView;
公共类浮动WebViewTestActivity扩展了FragmentActivity{
公共最终int viewId=0x12345678;
@凌驾
创建时的公共void(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
FrameLayout.LayoutParams lp=新的FrameLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_父级,ViewGroup.LayoutParams.MATCH_父级);
FrameLayout frame=新的FrameLayout(此);
frame.setId(viewId);
setContentView(帧,lp);
FloatingWebViewICSFragment=新的FloatingWebViewICSFragment();
getSupportFragmentManager().beginTransaction().add(视图ID,片段).commit();
}
公共静态类FloatingWebViewICSFragment扩展了片段{
私有最终字符串htmlBody=“

这是测试文档。这是测试文档。这是测试文档。这是测试文档。这是测试文档。这是测试文档。这是测试文档。这是测试文档。这是测试文档。这是测试文档。这是测试文档。这是测试文档。这是测试文档。这是测试文档。这是测试文档。这是测试文档。这是测试文档。这是测试文档。这是测试文档。这是测试文档。这是测试文档。这是测试文档。这是测试文档。这是测试文档。这是测试文档。这是测试文档。这是测试文档。这是测试文档。这是测试文档。这是测试文档。这是测试文档。这是测试文档t、 “; @凌驾 创建时的公共void(Bundle savedInstanceState){ super.onCreate(savedInstanceState); } @凌驾 CreateView上的公共视图(布局、充气机、视图组容器、捆绑包保存状态){ TextView TextView=newtextView(getActivity().getApplicationContext()); setText(“测试活动”); WebView WebView=新的WebView(getActivity().getApplicationContext()); webView.loadDataWithBaseURL(“file:///android_asset/,htmlBody,“text/html”、“UTF-8”、“关于:空白”); webView.setScrollBarStyle(视图.滚动条\u内部\u覆盖); webView.setScrollContainer(false); TextView textView2=新的TextView(getActivity().getApplicationContext()); textView2.setText(“测试活动”); FrameLayout.LayoutParams lp=新的FrameLayout.LayoutParams(ViewGroup.LayoutParams.FILL\u父级,ViewGroup.LayoutParams.FILL\u父级); LinearLayout布局=新的LinearLayout(getActivity().getApplicationContext()); 布局。setLayoutParams(lp); 布局。设置方向(线性布局。垂直); layout.addView(textView); layout.addView(webView); layout.addView(textView2); ScrollView ScrollView=新的ScrollView(getActivity().getApplicationContext()); scrollView.setLayoutParams(lp); scrollView.addView(布局); 返回滚动视图; } } }


我不知道如何修复它,但我现在知道了原因。WebView的内容由android.webkit.WebViewCore在其单独的工作线程中呈现。它们正在相互通信。当WebView需要重新呈现时,它会发送一个“请呈现”“将消息发送到WebViewCore,当WVC准备就绪时,将返回结果。关键是,它们的呈现与其他UI元素的呈现不同步,因为它是在单独的非UI线程上完成的

我想他们是想避免在渲染过程中阻塞ui线程。那太好了。但它会导致其他问题。。。就像你的一样