在 webview 上添加 pull to refresh 以进行刷新

Adding pull to refresh on webview for refreshing

我将在我的 webview 上添加拉动刷新,以便它刷新我的 webview。我已经看到此页面上的所有问题,但我找不到添加拉动刷新的好方法...

Mainactivity.java

package com.vvhvb.hesselfeenstra.vvheerenveenseboys;

import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.webkit.WebView;
import android.webkit.WebViewClient;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        String url ="http://heerenveenseboys.nl/";
        WebView view=(WebView) this.findViewById(R.id.webView);
        view.getSettings().setJavaScriptEnabled(true);
        view.getSettings().setBuiltInZoomControls(true);
        view.getSettings().setDisplayZoomControls(false);
        view.setWebViewClient(new WebViewClient());
        view.loadUrl(url);

    }

}

content_main.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    app:layout_behavior="@string/appbar_scrolling_view_behavior"
    tools:context="com.vvhvb.hesselfeenstra.vvheerenveenseboys.MainActivity"
    tools:showIn="@layout/activity_main">

    <WebView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/webView"
        android:layout_alignParentBottom="true"
        android:layout_alignParentRight="true"
        android:layout_alignParentEnd="true"
        android:layout_alignParentTop="true"
        android:layout_alignParentLeft="true"
        android:layout_alignParentStart="true" />
</RelativeLayout>

我希望任何人都可以帮助我并为我解决这个问题。

如果你只想拉动刷新,试试这个

    ll = (LinearLayout)findViewById(R.id.CategorySelect_lLayout_noID);
ll.setOnTouchListener(new OnTouchListener() {

    public boolean onTouch(View v, MotionEvent event) {

        if(event.getAction() == MotionEvent.ACTION_DOWN){
            Toast.makeText(CategorySelect.this, "action DOWN called", Toast.LENGTH_SHORT).show();
            return true;
        } 

        return false;
    }
});
    return true;
}

或者如果你想要一个图标或类似的东西 chrome

https://github.com/liaohuqiu/android-Ultra-Pull-To-Refresh

https://developer.android.com/training/swipe/add-swipe-interface.html

您可以使用滑动刷新布局,它易于使用并为您处理刷新动画。

您可以添加一个 OnRefreshListener 来刷新您的 webview

您可以像这样将 webview 包装在滑动刷新布局中

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
app:layout_behavior="@string/appbar_scrolling_view_behavior"
tools:context="com.vvhvb.hesselfeenstra.vvheerenveenseboys.MainActivity"
tools:showIn="@layout/activity_main">

<android.support.v4.widget.SwipeRefreshLayout
    android:id="@+id/swipeContainer"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    app:layout_behavior="@string/appbar_scrolling_view_behavior">

<android.support.v4.widget.NestedScrollView
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <WebView
        android:id="@+id/webView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:layout_alignParentEnd="true"
        android:layout_alignParentLeft="true"
        android:layout_alignParentRight="true"
        android:layout_alignParentStart="true"
        android:layout_alignParentTop="true" />

</android.support.v4.widget.NestedScrollView>
</android.support.v4.widget.SwipeRefreshLayout>
</RelativeLayout>

在java

package com.vvhvb.hesselfeenstra.vvheerenveenseboys;

import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.webkit.WebView;
import android.webkit.WebViewClient;

public class MainActivity extends AppCompatActivity {
WebView view;
SwipeRefreshLayout mySwipeRefreshLayout;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    mySwipeRefreshLayout = (SwipeRefreshLayout)this.findViewById(R.id.swipeContainer);
    String url ="http://heerenveenseboys.nl/";
    view=(WebView) this.findViewById(R.id.webView);
    view.getSettings().setJavaScriptEnabled(true);
    view.getSettings().setBuiltInZoomControls(true);
    view.getSettings().setDisplayZoomControls(false);
    view.setWebViewClient(new WebViewClient());
    view.loadUrl(url);

    mySwipeRefreshLayout.setOnRefreshListener(
    new SwipeRefreshLayout.OnRefreshListener() {
    @Override
    public void onRefresh() {
        view.reload();
    }
    }
    );

}

}

我认为最好的解决方案是使用 SwipeRefreshLayout 但不使用 NestedScrollView 作为 described, beacause this possible problem : .But there is another solution for scrolling problem as described by vizZ 来实现 ViewTreeObserver.OnScrollChangedListener。所以工作解决方案应该是这样的:

<android.support.v4.widget.SwipeRefreshLayout
        android:id="@+id/swipeContainer"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:layout_behavior="@string/appbar_scrolling_view_behavior">

        <RelativeLayout
            android:id="@+id/nonVideoLayout"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:windowSoftInputMode="adjustResize">

            <WebView
                android:id="@+id/main_web_view"
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:layout_marginTop="5dp"
                android:windowSoftInputMode="adjustResize"
                app:layout_constraintDimensionRatio="1" />

        </RelativeLayout>


    </android.support.v4.widget.SwipeRefreshLayout>

Activity 参数:

private WebView mWebView;
private SwipeRefreshLayout mySwipeRefreshLayout;
private ViewTreeObserver.OnScrollChangedListener mOnScrollChangedListener;   

在 Activity onCreate:

mWebView = (WebView) findViewById(R.id.main_web_view);
mySwipeRefreshLayout = (SwipeRefreshLayout)this.findViewById(R.id.swipeContainer);

        mySwipeRefreshLayout.setOnRefreshListener(
                new SwipeRefreshLayout.OnRefreshListener() {
                    @Override
                    public void onRefresh() {
                        mWebView.reload();
                    }
                }
        );

和 activity 的实现:implements AdvancedWebView.Listener

于 Activity onStop :

mySwipeRefreshLayout.getViewTreeObserver().removeOnScrollChangedListener(mOnScrollChangedListener);

和Activity onStart:

 mySwipeRefreshLayout.getViewTreeObserver().addOnScrollChangedListener(mOnScrollChangedListener =
                new ViewTreeObserver.OnScrollChangedListener() {
                    @Override
                    public void onScrollChanged() {
                        if (mWebView.getScrollY() == 0)
                            mySwipeRefreshLayout.setEnabled(true);
                        else
                            mySwipeRefreshLayout.setEnabled(false);

                    }
                });

这应该可以完美运行!在布局文件中,将 webview 包装在 SwipeRefreshLayout 中。

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/activity_main"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    >
    <android.support.v4.widget.SwipeRefreshLayout
        android:id="@+id/swipeContainer"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
    >
    <WebView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_alignParentTop="true"
        android:layout_alignParentLeft="true"
        android:layout_alignParentStart="true"
        android:id="@+id/webView"
       />
    </android.support.v4.widget.SwipeRefreshLayout>
</RelativeLayout>

在您的 Java 文件中,声明 SwipeRefreshLayout mySwipeRefreshLayout; class 之外。 然后,将其添加到 onCreate() 方法

    mySwipeRefreshLayout = (SwipeRefreshLayout)this.findViewById(R.id.swipeContainer);

        mySwipeRefreshLayout.setOnRefreshListener(
                        new SwipeRefreshLayout.OnRefreshListener() {
                            @Override
                            public void onRefresh() {
                                    mWebview.reload();
        mWebview.getSettings().setCacheMode(WebSettings.LOAD_DEFAULT);
// This is important as it forces webview to load from the instead of reloading from cache

        mWebview .loadUrl(getString(R.string.app_link));

                            }
                        }
                );

activity_main.xml

<android.support.v4.widget.SwipeRefreshLayout
        android:id="@+id/swipeContainer"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:layout_behavior="@string/appbar_scrolling_view_behavior">
<WebView
        android:id="@+id/webview"
        android:layout_width="match_parent"
        android:layout_height="match_parent" app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent" app:layout_constraintTop_toTopOf="parent"
        android:layout_marginTop="0dp"
        android:layout_marginLeft="0dp"
        android:layout_marginStart="0dp"
        android:layout_marginEnd="0dp"
        android:layout_marginRight="0dp"
        android:layout_marginBottom="0dp"
        app:layout_constraintBottom_toBottomOf="parent"/>
</android.support.v4.widget.SwipeRefreshLayout>

对于 Kotllin:

MainActivity.kt

var mySwipeRefreshLayout: SwipeRefreshLayout? = null
var myWebView: WebView? = null
mySwipeRefreshLayout = findViewById<SwipeRefreshLayout>(R.id.swipeContainer)

    mySwipeRefreshLayout?.setOnRefreshListener {
        Log.i("on refresh", "onRefresh called from SwipeRefreshLayout")

        // This method performs the actual data-refresh operation.
        // The method calls setRefreshing(false) when it's finished.
        myWebView?.reload();
    }
myWebView!!.webViewClient = object : WebViewClient() {
        override fun shouldOverrideUrlLoading(view: WebView?, url: String?): Boolean {
            view?.loadUrl("http://www.google.com")
            return false;
        }

        override fun onPageFinished(view: WebView?, url: String?) {
            mySwipeRefreshLayout?.isRefreshing = false
        }
    }

在研究过程中,我发现可以通过三种简单的方法在 Android 应用程序中实现下拉刷新:

  • 您可以使用第三方库/SDK
  • 您可以使用自定义实现(例如此处提到的代码片段)。此选项更复杂,但为自定义提供了更大的灵活性
  • 在 Android WebViewGold 中,在 Config.java 内,只需将 ENABLE__PULL_REFRESH 设为 true

滚动愉快!

这是对我有用的代码部分。它处理两个问题:

  1. 当用户在 web 视图中滚动并且比用户再次尝试向上滚动时屏幕被刷新。但是,在 onStart() 和 onStop() 中添加代码会处理此问题,它会检查用户是否在 webview 中滚动,而不是禁用刷新部分。

  2. 使用 WebViewClient() 调用 onPageFinished() 会禁用刷新图标,否则它将进入永久刷新循环。

    webView = findViewById(R.id.webview);
    mySwipeRefreshLayout = (SwipeRefreshLayout)this.findViewById(R.id.swipeContainer);
    
    webView.getSettings().setJavaScriptEnabled(true);
    webView.getSettings().setBuiltInZoomControls(true);
    webView.getSettings().setDisplayZoomControls(true);
    webView.setWebViewClient(new WebViewClient() {
        @Override
        public void onPageFinished(WebView view, String url) {
            mySwipeRefreshLayout.setRefreshing(false);
        }
    });
    webView.loadUrl("https://www.enter your url here");
    
    mySwipeRefreshLayout.setOnRefreshListener(
            new SwipeRefreshLayout.OnRefreshListener() {
                @Override
                public void onRefresh() {
                    webView.reload();
                }
            });
    
    
          }
    
      @Override
         protected void onStart() {
          super.onStart();
    
       mySwipeRefreshLayout.getViewTreeObserver()
          .addOnScrollChangedListener(mOnScrollChangedListener =
            new ViewTreeObserver.OnScrollChangedListener() {
                @Override
                public void onScrollChanged() {
                    if (webView.getScrollY() == 0)
                        mySwipeRefreshLayout.setEnabled(true);
                    else
                        mySwipeRefreshLayout.setEnabled(false);
    
                }
            });
             }
    
    
        @Override
         protected void onStop() {
           super.onStop();
              mySwipeRefreshLayout.getViewTreeObserver()
        .removeOnScrollChangedListener(mOnScrollChangedListener);
          }