在 Xamarin Android Webview 中将 WebHistory 项数组转换为字符串数组
Convert WebHistory Item array to String Array in Xamarin Android Webview
我有一个 activity 应该显示用户访问过的 URL 列表,我使用 WebViewHistory 项目逻辑获取历史记录并使用 ListView 数组适配器将数据填充到我的布局中。除了 WebViewHistory 项是以这种人类无法理解的机器语言显示的。例如,一个列表的历史记录为 p7@5561337
。我只需要可用于将 WebViewHistoryItem 数组转换为人类可读字符串数组的代码
class History : AppCompatActivity
{
ListView listView;
WebView mywebview;
protected override void OnCreate(Bundle savedInstanceState)
{
mywebview = Internet.webview;
WebHistoryItem[] webHistories = new WebHistoryItem[size];
int size = webviewHistory.Size;
for(int i = 0; i <size; i++)
{
webHistories[i] = webviewHistory.GetItemAtIndex(i);
}
//Locate listview in Resource Layout
histView = (ListView)FindViewById<ListView>(Resource.Id.mainlistview);
//populate webview history item into listview
histView.Adapter = new ArrayAdapter(this,
Android.Resource.Layout.SimpleListItem1,webHistories);
}
}
我在之前的 Activity 中将 webview 定义为静态和 public 让我在这个 activity 中访问它的实例,我如何将 webhistories
数组转换为 string
非常感谢您的帮助
i got something, I can get the Title of the current url via this method string[] my=new string[] { webviewHistory.CurrentItem.Title } ;
, Can we reason it out from here?
是的。
Am using this but am still getting the storage pointer of the urls, please help string[] histo = new string[] { webviewHistory.GetItemAtIndex(0).Url.ToString()};
您可以使用List
来包含历史记录。我创建了一个名为 VisitHistroy
的模型。并在列表视图中同时显示标题和 url,就像这个 GIF。
这是我的完整代码。
[Activity(Label = "@string/app_name", Theme = "@style/AppTheme", MainLauncher = true)]
public class MainActivity : AppCompatActivity
{
EditText editText1;
WebView webView1;
ListView listView1;
Button button1;
public delegate void OnLinkSelectedHandler(string url);
protected override void OnCreate(Bundle savedInstanceState)
{
base.OnCreate(savedInstanceState);
Xamarin.Essentials.Platform.Init(this, savedInstanceState);
// Set our view from the "main" layout resource
SetContentView(Resource.Layout.activity_main);
editText1= FindViewById<EditText>(Resource.Id.editText1);
webView1 = FindViewById<WebView>(Resource.Id.webView1);
listView1 = FindViewById<ListView>(Resource.Id.listView1);
button1= FindViewById<Button>(Resource.Id.button1);
button1.Click += Button1_Click;
webView1.LoadUrl("http://whosebug.com");
webView1.Settings.JavaScriptEnabled = true;
webView1.SetWebViewClient(new MyWebviewClient(this.ISVistedSoLink));
}
private void Button1_Click(object sender, System.EventArgs e)
{
// throw new System.NotImplementedException();
WebBackForwardList wbfl = webView1.CopyBackForwardList();
int size = wbfl.Size;
var webHistories = new WebHistoryItem[wbfl.Size];
List<VisitHistroy> strs = new List<VisitHistroy>();
for (int i = 0; i < size; i++)
{
// histo = new string[] { wbfl.GetItemAtIndex(0).Url.ToString() };
strs.Add(new VisitHistroy() { Title = wbfl.GetItemAtIndex(i).Title.ToString(), Url = wbfl.GetItemAtIndex(i).Url.ToString() });
}
//SimpleAdapter(Context? context, IList<IDictionary<string, object>>? data, int resource, string[]? from, int[]? to);
listView1.Adapter = new MyAdapter(this, strs);
}
public void ISVistedSoLink(string url)
{
editText1.Text = url;
}
public override void OnRequestPermissionsResult(int requestCode, string[] permissions, [GeneratedEnum] Android.Content.PM.Permission[] grantResults)
{
Xamarin.Essentials.Platform.OnRequestPermissionsResult(requestCode, permissions, grantResults);
base.OnRequestPermissionsResult(requestCode, permissions, grantResults);
}
}
internal class MyAdapter : BaseAdapter<VisitHistroy>
{
private MainActivity mainActivity;
private List<VisitHistroy> strs;
public MyAdapter(MainActivity mainActivity, List<VisitHistroy> strs):base()
{
this.mainActivity = mainActivity;
this.strs = strs;
}
public override VisitHistroy this[int position] => strs[position];
public override int Count => strs.Count;
public override long GetItemId(int position)
{
return position;
}
public override View GetView(int position, View convertView, ViewGroup parent)
{
var item = strs[position];
View view = convertView;
if (view == null) // no view to re-use, create new
view = mainActivity.LayoutInflater.Inflate(Resource.Layout.Itemlayout, null);
view.FindViewById<TextView>(Resource.Id.itemTitle).Text = item.Title;
view.FindViewById<TextView>(Resource.Id.itemurl).Text = item.Url;
return view;
}
}
public class VisitHistroy
{
public string Title { get; set; }
public string Url { get; set; }
}
}
这是自定义项。
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:textSize="15dp"
android:textStyle="bold"
android:text="@string/abc_font_family_title_material"
android:id="@+id/itemTitle"/>
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="@string/abc_font_family_title_material"
android:id="@+id/itemurl"/>
</LinearLayout>
这里是activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent">
<EditText
android:inputType="text"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="@+id/editText1"/>
<Button
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Get"
android:id="@+id/button1"/>
<android.webkit.WebView
android:layout_width="match_parent"
android:layout_height="350dip"
android:id="@+id/webView1"
/>
<ListView
android:id="@+id/listView1"
android:layout_width="match_parent"
android:layout_height="200dip"/>
</LinearLayout>
我有一个 activity 应该显示用户访问过的 URL 列表,我使用 WebViewHistory 项目逻辑获取历史记录并使用 ListView 数组适配器将数据填充到我的布局中。除了 WebViewHistory 项是以这种人类无法理解的机器语言显示的。例如,一个列表的历史记录为 p7@5561337
。我只需要可用于将 WebViewHistoryItem 数组转换为人类可读字符串数组的代码
class History : AppCompatActivity
{
ListView listView;
WebView mywebview;
protected override void OnCreate(Bundle savedInstanceState)
{
mywebview = Internet.webview;
WebHistoryItem[] webHistories = new WebHistoryItem[size];
int size = webviewHistory.Size;
for(int i = 0; i <size; i++)
{
webHistories[i] = webviewHistory.GetItemAtIndex(i);
}
//Locate listview in Resource Layout
histView = (ListView)FindViewById<ListView>(Resource.Id.mainlistview);
//populate webview history item into listview
histView.Adapter = new ArrayAdapter(this,
Android.Resource.Layout.SimpleListItem1,webHistories);
}
}
我在之前的 Activity 中将 webview 定义为静态和 public 让我在这个 activity 中访问它的实例,我如何将 webhistories
数组转换为 string
非常感谢您的帮助
i got something, I can get the Title of the current url via this method
string[] my=new string[] { webviewHistory.CurrentItem.Title } ;
, Can we reason it out from here?
是的。
Am using this but am still getting the storage pointer of the urls, please help string[] histo = new string[] { webviewHistory.GetItemAtIndex(0).Url.ToString()};
您可以使用List
来包含历史记录。我创建了一个名为 VisitHistroy
的模型。并在列表视图中同时显示标题和 url,就像这个 GIF。
这是我的完整代码。
[Activity(Label = "@string/app_name", Theme = "@style/AppTheme", MainLauncher = true)]
public class MainActivity : AppCompatActivity
{
EditText editText1;
WebView webView1;
ListView listView1;
Button button1;
public delegate void OnLinkSelectedHandler(string url);
protected override void OnCreate(Bundle savedInstanceState)
{
base.OnCreate(savedInstanceState);
Xamarin.Essentials.Platform.Init(this, savedInstanceState);
// Set our view from the "main" layout resource
SetContentView(Resource.Layout.activity_main);
editText1= FindViewById<EditText>(Resource.Id.editText1);
webView1 = FindViewById<WebView>(Resource.Id.webView1);
listView1 = FindViewById<ListView>(Resource.Id.listView1);
button1= FindViewById<Button>(Resource.Id.button1);
button1.Click += Button1_Click;
webView1.LoadUrl("http://whosebug.com");
webView1.Settings.JavaScriptEnabled = true;
webView1.SetWebViewClient(new MyWebviewClient(this.ISVistedSoLink));
}
private void Button1_Click(object sender, System.EventArgs e)
{
// throw new System.NotImplementedException();
WebBackForwardList wbfl = webView1.CopyBackForwardList();
int size = wbfl.Size;
var webHistories = new WebHistoryItem[wbfl.Size];
List<VisitHistroy> strs = new List<VisitHistroy>();
for (int i = 0; i < size; i++)
{
// histo = new string[] { wbfl.GetItemAtIndex(0).Url.ToString() };
strs.Add(new VisitHistroy() { Title = wbfl.GetItemAtIndex(i).Title.ToString(), Url = wbfl.GetItemAtIndex(i).Url.ToString() });
}
//SimpleAdapter(Context? context, IList<IDictionary<string, object>>? data, int resource, string[]? from, int[]? to);
listView1.Adapter = new MyAdapter(this, strs);
}
public void ISVistedSoLink(string url)
{
editText1.Text = url;
}
public override void OnRequestPermissionsResult(int requestCode, string[] permissions, [GeneratedEnum] Android.Content.PM.Permission[] grantResults)
{
Xamarin.Essentials.Platform.OnRequestPermissionsResult(requestCode, permissions, grantResults);
base.OnRequestPermissionsResult(requestCode, permissions, grantResults);
}
}
internal class MyAdapter : BaseAdapter<VisitHistroy>
{
private MainActivity mainActivity;
private List<VisitHistroy> strs;
public MyAdapter(MainActivity mainActivity, List<VisitHistroy> strs):base()
{
this.mainActivity = mainActivity;
this.strs = strs;
}
public override VisitHistroy this[int position] => strs[position];
public override int Count => strs.Count;
public override long GetItemId(int position)
{
return position;
}
public override View GetView(int position, View convertView, ViewGroup parent)
{
var item = strs[position];
View view = convertView;
if (view == null) // no view to re-use, create new
view = mainActivity.LayoutInflater.Inflate(Resource.Layout.Itemlayout, null);
view.FindViewById<TextView>(Resource.Id.itemTitle).Text = item.Title;
view.FindViewById<TextView>(Resource.Id.itemurl).Text = item.Url;
return view;
}
}
public class VisitHistroy
{
public string Title { get; set; }
public string Url { get; set; }
}
}
这是自定义项。
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:textSize="15dp"
android:textStyle="bold"
android:text="@string/abc_font_family_title_material"
android:id="@+id/itemTitle"/>
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="@string/abc_font_family_title_material"
android:id="@+id/itemurl"/>
</LinearLayout>
这里是activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent">
<EditText
android:inputType="text"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="@+id/editText1"/>
<Button
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Get"
android:id="@+id/button1"/>
<android.webkit.WebView
android:layout_width="match_parent"
android:layout_height="350dip"
android:id="@+id/webView1"
/>
<ListView
android:id="@+id/listView1"
android:layout_width="match_parent"
android:layout_height="200dip"/>
</LinearLayout>