不幸的是，应用程序在片段视图中单击已添加书签的项目时停止了我正在使用 json 来存储标题和链接
Application unfortunately stopped on clicking bookmarked item in fragment view Im using json to store title & links
您好，我正在开发带有书签的 Webview 应用程序。使用 fab 按钮为页面添加书签。单击 fab 按钮标题和 links 存储在 json 中，书签页面 link 和标题可以在 fragment_fav.xml 中查看
但是当我点击保存的项目应用程序停止。我希望 links 加载到 webview 而不是停止。
如下所述的代码列表和 logcat 错误
我是 android 的新手，请评论您的答案。
LOGCAT
03-07 12:44:12.088 14138-14138/seacoders.abhilash.bogguru E/dalvikvm: Could not find class 'android.support.v4.app.ActivityCompat$SharedElementCallback23Impl', referenced from method android.support.v4.app.ActivityCompat.setEnterSharedElementCallback
03-07 12:44:12.089 14138-14138/seacoders.abhilash.bogguru E/dalvikvm: Could not find class 'android.support.v4.app.ActivityCompat$SharedElementCallback21Impl', referenced from method android.support.v4.app.ActivityCompat.setEnterSharedElementCallback
03-07 12:44:12.090 14138-14138/seacoders.abhilash.bogguru E/dalvikvm: Could not find class 'android.support.v4.app.ActivityCompat$SharedElementCallback23Impl', referenced from method android.support.v4.app.ActivityCompat.setExitSharedElementCallback
03-07 12:44:12.092 14138-14138/seacoders.abhilash.bogguru E/dalvikvm: Could not find class 'android.support.v4.app.ActivityCompat$SharedElementCallback21Impl', referenced from method android.support.v4.app.ActivityCompat.setExitSharedElementCallback
03-07 12:44:12.169 14138-14138/seacoders.abhilash.bogguru E/AndroidRuntime: FATAL EXCEPTION: main
android.content.ActivityNotFoundException: Unable to find explicit activity class {seacoders.abhilash.bogguru/seacoders.abhilash.bogguru.HomeFragment}; have you declared this activity in your AndroidManifest.xml?
at android.app.Instrumentation.checkStartActivityResult(Instrumentation.java:1624)
at android.app.Instrumentation.execStartActivity(Instrumentation.java:1423)
at android.app.Activity.startActivityForResult(Activity.java:3488)
at android.support.v4.app.BaseFragmentActivityApi16.startActivityForResult(BaseFragmentActivityApi16.java:54)
at android.support.v4.app.FragmentActivity.startActivityForResult(FragmentActivity.java:67)
at android.support.v4.app.ActivityCompat.startActivityForResult(ActivityCompat.java:152)
at android.support.v4.app.FragmentActivity.startActivityFromFragment(FragmentActivity.java:793)
at android.support.v4.app.FragmentActivity$HostCallbacks.onStartActivityFromFragment(FragmentActivity.java:907)
at android.support.v4.app.Fragment.startActivity(Fragment.java:1009)
at android.support.v4.app.Fragment.startActivity(Fragment.java:998)
at seacoders.abhilash.bogguru.FavFragment.onItemClick(FavFragment.java:82)
at android.widget.AdapterView.performItemClick(AdapterView.java:298)
at android.widget.AbsListView.performItemClick(AbsListView.java:1128)
at android.widget.AbsListView$PerformClick.run(AbsListView.java:2815)
at android.widget.AbsListView.run(AbsListView.java:3574)
at android.os.Handler.handleCallback(Handler.java:800)
at android.os.Handler.dispatchMessage(Handler.java:100)
at android.os.Looper.loop(Looper.java:194)
at android.app.ActivityThread.main(ActivityThread.java:5371)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:525)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:833)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:600)
at dalvik.system.NativeStart.main(Native Method)
FavFragment.java
package seacoders.abhilash.bogguru;
import android.app.AlertDialog;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.SharedPreferences;
import android.os.AsyncTask;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v4.app.Fragment;
import android.support.v4.widget.SwipeRefreshLayout;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.webkit.WebView;
import android.widget.AdapterView;
import android.widget.LinearLayout;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.SimpleAdapter;
import com.google.gson.Gson;
import com.google.gson.reflect.TypeToken;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Map;
public class FavFragment extends Fragment {
ArrayList<HashMap<String, String>> listRowData;
public static final String PREFERENCES = "PREFERENCES_NAME";
public static final String WEB_LINKS = "links";
public static final String WEB_TITLE = "title";
public static String TAG_TITLE = "title";
public static String TAG_LINK = "link";
ListView listView;
ListAdapter adapter;
LinearLayout linearLayout;
SwipeRefreshLayout mSwipeRefreshLayout;
public static final String TITLE = "BOOKMARKS";
public static FavFragment newInstance() {
return new FavFragment();
}
@Nullable
@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, Bundle savedInstanceState) {
View v=inflater.inflate(R.layout.fragment_fav, container, false);
listView = v.findViewById(R.id.listView);
linearLayout = v.findViewById(R.id.emptyList);
mSwipeRefreshLayout = v.findViewById(R.id.swipeToRefresh);
mSwipeRefreshLayout.setColorSchemeResources(R.color.colorAccent);
mSwipeRefreshLayout.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {
@Override
public void onRefresh() {
new LoadBookmarks().execute();
}
});
new LoadBookmarks().execute();
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
Object o = listView.getAdapter().getItem(position);
if (o instanceof Map) {
Map map = (Map) o;
Intent in = new Intent(getActivity(),HomeFragment.class);
in.putExtra("url", String.valueOf(map.get(TAG_LINK)));
String.valueOf(map.get(TAG_LINK));
startActivity(in);
}
}
});
listView.setOnItemLongClickListener(new AdapterView.OnItemLongClickListener() {
@Override
public boolean onItemLongClick(AdapterView<?> adapterView, View view, int i, long l) {
Object o = listView.getAdapter().getItem(i);
if (o instanceof Map) {
Map map = (Map) o;
deleteBookmark(String.valueOf(map.get(TAG_TITLE)), String.valueOf(map.get(TAG_LINK)));
}
return true;
}
});
return v;
}
private void deleteBookmark(final String title, final String link) {
new AlertDialog.Builder(getActivity())
.setTitle("DELETE")
.setMessage("Confirm that you want to delete this bookmark?")
.setPositiveButton("YES", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialogInterface, int i) {
SharedPreferences sharedPreferences = getActivity().getSharedPreferences(PREFERENCES, Context.MODE_PRIVATE);
String jsonLink = sharedPreferences.getString(WEB_LINKS, null);
String jsonTitle = sharedPreferences.getString(WEB_TITLE, null);
if (jsonLink != null && jsonTitle != null) {
Gson gson = new Gson();
ArrayList<String> linkArray = gson.fromJson(jsonLink, new TypeToken<ArrayList<String>>() {
}.getType());
ArrayList<String> titleArray = gson.fromJson(jsonTitle, new TypeToken<ArrayList<String>>() {
}.getType());
linkArray.remove(link);
titleArray.remove(title);
SharedPreferences.Editor editor = sharedPreferences.edit();
editor.putString(WEB_LINKS, new Gson().toJson(linkArray));
editor.putString(WEB_TITLE, new Gson().toJson(titleArray));
editor.apply();
new LoadBookmarks().execute();
}
dialogInterface.dismiss();
}
}).setNegativeButton("NO", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialogInterface, int i) {
dialogInterface.dismiss();
}
}).show();
}
private class LoadBookmarks extends AsyncTask<String, String, String> {
@Override
protected void onPreExecute() {
super.onPreExecute();
}
@Override
protected String doInBackground(String... args) {
// updating UI from Background Thread
getActivity().runOnUiThread(new Runnable() {
public void run() {
SharedPreferences sharedPreferences = getActivity().getSharedPreferences(PREFERENCES, Context.MODE_PRIVATE);
String jsonLink = sharedPreferences.getString(WEB_LINKS, null);
String jsonTitle = sharedPreferences.getString(WEB_TITLE, null);
listRowData = new ArrayList<>();
if (jsonLink != null && jsonTitle != null) {
Gson gson = new Gson();
ArrayList<String> linkArray = gson.fromJson(jsonLink, new TypeToken<ArrayList<String>>() {
}.getType());
ArrayList<String> titleArray = gson.fromJson(jsonTitle, new TypeToken<ArrayList<String>>() {
}.getType());
for (int i = 0; i < linkArray.size(); i++) {
HashMap<String, String> map = new HashMap<>();
if (titleArray.get(i).length() == 0)
map.put(TAG_TITLE, "Bookmark " + (i + 1));
else
map.put(TAG_TITLE, titleArray.get(i));
map.put(TAG_LINK, linkArray.get(i));
listRowData.add(map);
}
adapter = new SimpleAdapter(getActivity(),
listRowData, R.layout.bookmark_list_row,
new String[]{TAG_TITLE, TAG_LINK},
new int[]{R.id.title, R.id.link});
listView.setAdapter(adapter);
}
linearLayout.setVisibility(View.VISIBLE);
listView.setEmptyView(linearLayout);
}
});
return null;
}
protected void onPostExecute(String args) {
mSwipeRefreshLayout.setRefreshing(false);
}
}
}
fragment_fav.xml
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="@+id/favourite"
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.v4.widget.SwipeRefreshLayout
android:id="@+id/swipeToRefresh"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="@dimen/fab_margin">
<ListView
android:id="@+id/listView"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
</android.support.v4.widget.SwipeRefreshLayout>
<LinearLayout
android:id="@+id/emptyList"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:gravity="center"
android:orientation="vertical"
android:visibility="gone">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:gravity="center"
android:text="WHOOPS"
android:textColor="#212121"
android:textSize="20sp"
android:textStyle="bold" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:gravity="center"
android:text="There are no bookmarks at the moment"
android:textColor="#212121" />
</LinearLayout>
</android.support.constraint.ConstraintLayout>
HomeFragment.java
package seacoders.abhilash.bogguru;
import android.content.Context;
import android.content.SharedPreferences;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.graphics.Bitmap;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v4.app.Fragment;
import android.support.v4.view.GravityCompat;
import android.support.v4.widget.DrawerLayout;
import android.view.KeyEvent;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.webkit.WebSettings;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.ProgressBar;
import android.widget.TextView;
import android.widget.Toast;
import com.google.gson.Gson;
import com.google.gson.reflect.TypeToken;
import java.net.URI;
import java.util.ArrayList;
import static android.content.Intent.getIntent;
public class HomeFragment extends Fragment {
WebView wv;
TextView txt;
ProgressBar pbar;
DatabaseHelper myDb;
public static final String PREFERENCES = "PREFERENCES_NAME";
String WEB_LINKS = "links";
String WEB_TITLE = "title";
String current_page_url;
public static final String TITLE = "Home";
public static HomeFragment newInstance() {
return new HomeFragment();
}
@Nullable
@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, Bundle savedInstanceState) {
//return inflater.inflate(R.layout.fragment_home, container, false);
View v=inflater.inflate(R.layout.fragment_home, container, false);
wv = (WebView)v.findViewById(R.id.webview);
wv.loadUrl("http://www.google.com");
current_page_url = wv.getUrl();
SharedPreferences sharedPreferences = getActivity().getSharedPreferences(PREFERENCES, Context.MODE_PRIVATE);
String links = sharedPreferences.getString(WEB_LINKS, null);
if (links != null) {
Gson gson = new Gson();
ArrayList<String> linkList = gson.fromJson(links, new TypeToken<ArrayList<String>>() {
}.getType());
}
FloatingActionButton fab = (FloatingActionButton)v.findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
SharedPreferences sharedPreferences = getActivity().getSharedPreferences(PREFERENCES, Context.MODE_PRIVATE);
String jsonLink = sharedPreferences.getString(WEB_LINKS, null);
String jsonTitle = sharedPreferences.getString(WEB_TITLE, null);
if (jsonLink != null && jsonTitle != null) {
Gson gson = new Gson();
ArrayList<String> linkList = gson.fromJson(jsonLink, new TypeToken<ArrayList<String>>() {
}.getType());
ArrayList<String> titleList = gson.fromJson(jsonTitle, new TypeToken<ArrayList<String>>() {
}.getType());
if (linkList.contains(current_page_url)) {
linkList.remove(wv.getUrl());
titleList.remove(wv.getTitle().trim());
SharedPreferences.Editor editor = sharedPreferences.edit();
editor.putString(WEB_LINKS, new Gson().toJson(linkList));
editor.putString(WEB_TITLE, new Gson().toJson(titleList));
editor.apply();
Snackbar.make(view, "Bookmark removed from favourites", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
} else {
linkList.add(wv.getUrl());
titleList.add(wv.getTitle().trim());
SharedPreferences.Editor editor = sharedPreferences.edit();
editor.putString(WEB_LINKS, new Gson().toJson(linkList));
editor.putString(WEB_TITLE, new Gson().toJson(titleList));
editor.apply();
Snackbar.make(view, "Bookmark added, view in favourites", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
}
} else {
ArrayList<String> linkList = new ArrayList<>();
ArrayList<String> titleList = new ArrayList<>();
linkList.add(wv.getUrl());
titleList.add(wv.getTitle());
SharedPreferences.Editor editor = sharedPreferences.edit();
editor.putString(WEB_LINKS, new Gson().toJson(linkList));
editor.putString(WEB_TITLE, new Gson().toJson(titleList));
editor.apply();
Snackbar.make(view, "Bookmark added, view in favourites", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
}
}
});
WebSettings webSettings = wv.getSettings();
webSettings.setJavaScriptEnabled(true);
pbar = (ProgressBar) v.findViewById(R.id.pg1);
txt = (TextView) v.findViewById(R.id.txtload);
wv.setWebViewClient(new MyWebViewClient());
wv.setOnKeyListener(new View.OnKeyListener()
{
@Override
public boolean onKey(View v, int keyCode, KeyEvent event)
{
if(event.getAction() == KeyEvent.ACTION_DOWN)
{
switch(keyCode)
{
case KeyEvent.KEYCODE_BACK:
if(wv.canGoBack())
{
wv.goBack();
return true;
}
break;
}
}
return false;
}
});
return v;
}
public class MyWebViewClient extends WebViewClient {
public void onReceivedError(WebView v, int errorCode, String description, String failingUrl) {
wv.loadUrl("file:///android_asset/error.html");
}
@Override
public void onPageStarted(WebView view, String url, Bitmap favicon) {
super.onPageStarted(view, url, favicon);
System.out.println("loading... please wait");
pbar.setVisibility(View.VISIBLE);
txt.setVisibility(View.VISIBLE);
}
@Override
public void onPageFinished(WebView view, String url) {
System.out.println("finished loading");
pbar.setVisibility(View.GONE);
txt.setVisibility(View.GONE);
}
}
}
AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="seacoders.abhilash.bogguru">
<uses-permission android:name="android.permission.INTERNET"></uses-permission>
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"></uses-permission>
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE"></uses-permission>
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"></uses-permission>
<uses-permission android:name="android.permission.READ_HISTORY_BOOKMARKS"></uses-permission>
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"></uses-permission>
<uses-permission android:name="android.permission.WRITE_HISTORY_BOOKMARKS"></uses-permission>
<uses-permission android:name="android.permission.WRITE_SETTINGS"></uses-permission>
<application
android:largeHeap="true"
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:roundIcon="@mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="@style/AppTheme">
<activity
android:name=".MainActivity"
android:label="@string/app_name"
android:theme="@style/AppTheme.NoActionBar">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
错误来自 listview clicklistner
在 google 上搜索 call fragment in fragment 您可以尝试以下代码
// Create fragment and give it an argument specifying the article it should show
ArticleFragment newFragment = new ArticleFragment();
Bundle args = new Bundle();
args.putInt(ArticleFragment.ARG_POSITION, position);
newFragment.setArguments(args);
FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
// Replace whatever is in the fragment_container view with this fragment,
// and add the transaction to the back stack so the user can navigate back
transaction.replace(R.id.fragment_container, newFragment);
transaction.addToBackStack(null);
// Commit the transaction
transaction.commit();
现在你的代码看起来像
new LoadBookmarks().execute();
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
Object o = listView.getAdapter().getItem(position);
if (o instanceof Map) {
Map map = (Map) o;
HomeFragment newFragment = new HomeFragment();
Bundle args = new Bundle();
args.puString("url", String.valueOf(map.get(TAG_LINK)));
newFragment.setArguments(args);
FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
transaction.replace(R.id.fragment_container, newFragment);
transaction.addToBackStack(null);
transaction.commit();
}
}
});
大家好，我使用了以下代码，我的问题已经解决了
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
Object o = listView.getAdapter().getItem(position);
if (o instanceof Map) {
final Map map = (Map) o;
Intent in = new Intent(getActivity(),HomeFragment.class);
in.putExtra("url", String.valueOf(map.get(TAG_LINK)));
System.out.println("loading url..."+String.valueOf(map.get(TAG_LINK))+" please wait");
HomeFragment.wv.post(new Runnable() {
public void run() {
HomeFragment.wv.loadUrl(String.valueOf(map.get(TAG_LINK)));
}
});
seacoders.abhilash.bogguru.MainActivity.changefrag();
}
}
});
MainActivity 中的以下代码。
private static int getItem(int i) {
return mViewPager.getCurrentItem() + i;
}
public static void changefrag() {
mViewPager.setCurrentItem(getItem(-1),true);
}
您好，我正在开发带有书签的 Webview 应用程序。使用 fab 按钮为页面添加书签。单击 fab 按钮标题和 links 存储在 json 中，书签页面 link 和标题可以在 fragment_fav.xml 中查看 但是当我点击保存的项目应用程序停止。我希望 links 加载到 webview 而不是停止。 如下所述的代码列表和 logcat 错误 我是 android 的新手，请评论您的答案。
LOGCAT
03-07 12:44:12.088 14138-14138/seacoders.abhilash.bogguru E/dalvikvm: Could not find class 'android.support.v4.app.ActivityCompat$SharedElementCallback23Impl', referenced from method android.support.v4.app.ActivityCompat.setEnterSharedElementCallback
03-07 12:44:12.089 14138-14138/seacoders.abhilash.bogguru E/dalvikvm: Could not find class 'android.support.v4.app.ActivityCompat$SharedElementCallback21Impl', referenced from method android.support.v4.app.ActivityCompat.setEnterSharedElementCallback
03-07 12:44:12.090 14138-14138/seacoders.abhilash.bogguru E/dalvikvm: Could not find class 'android.support.v4.app.ActivityCompat$SharedElementCallback23Impl', referenced from method android.support.v4.app.ActivityCompat.setExitSharedElementCallback
03-07 12:44:12.092 14138-14138/seacoders.abhilash.bogguru E/dalvikvm: Could not find class 'android.support.v4.app.ActivityCompat$SharedElementCallback21Impl', referenced from method android.support.v4.app.ActivityCompat.setExitSharedElementCallback
03-07 12:44:12.169 14138-14138/seacoders.abhilash.bogguru E/AndroidRuntime: FATAL EXCEPTION: main
android.content.ActivityNotFoundException: Unable to find explicit activity class {seacoders.abhilash.bogguru/seacoders.abhilash.bogguru.HomeFragment}; have you declared this activity in your AndroidManifest.xml?
at android.app.Instrumentation.checkStartActivityResult(Instrumentation.java:1624)
at android.app.Instrumentation.execStartActivity(Instrumentation.java:1423)
at android.app.Activity.startActivityForResult(Activity.java:3488)
at android.support.v4.app.BaseFragmentActivityApi16.startActivityForResult(BaseFragmentActivityApi16.java:54)
at android.support.v4.app.FragmentActivity.startActivityForResult(FragmentActivity.java:67)
at android.support.v4.app.ActivityCompat.startActivityForResult(ActivityCompat.java:152)
at android.support.v4.app.FragmentActivity.startActivityFromFragment(FragmentActivity.java:793)
at android.support.v4.app.FragmentActivity$HostCallbacks.onStartActivityFromFragment(FragmentActivity.java:907)
at android.support.v4.app.Fragment.startActivity(Fragment.java:1009)
at android.support.v4.app.Fragment.startActivity(Fragment.java:998)
at seacoders.abhilash.bogguru.FavFragment.onItemClick(FavFragment.java:82)
at android.widget.AdapterView.performItemClick(AdapterView.java:298)
at android.widget.AbsListView.performItemClick(AbsListView.java:1128)
at android.widget.AbsListView$PerformClick.run(AbsListView.java:2815)
at android.widget.AbsListView.run(AbsListView.java:3574)
at android.os.Handler.handleCallback(Handler.java:800)
at android.os.Handler.dispatchMessage(Handler.java:100)
at android.os.Looper.loop(Looper.java:194)
at android.app.ActivityThread.main(ActivityThread.java:5371)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:525)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:833)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:600)
at dalvik.system.NativeStart.main(Native Method)
FavFragment.java
package seacoders.abhilash.bogguru;
import android.app.AlertDialog;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.SharedPreferences;
import android.os.AsyncTask;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v4.app.Fragment;
import android.support.v4.widget.SwipeRefreshLayout;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.webkit.WebView;
import android.widget.AdapterView;
import android.widget.LinearLayout;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.SimpleAdapter;
import com.google.gson.Gson;
import com.google.gson.reflect.TypeToken;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Map;
public class FavFragment extends Fragment {
ArrayList<HashMap<String, String>> listRowData;
public static final String PREFERENCES = "PREFERENCES_NAME";
public static final String WEB_LINKS = "links";
public static final String WEB_TITLE = "title";
public static String TAG_TITLE = "title";
public static String TAG_LINK = "link";
ListView listView;
ListAdapter adapter;
LinearLayout linearLayout;
SwipeRefreshLayout mSwipeRefreshLayout;
public static final String TITLE = "BOOKMARKS";
public static FavFragment newInstance() {
return new FavFragment();
}
@Nullable
@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, Bundle savedInstanceState) {
View v=inflater.inflate(R.layout.fragment_fav, container, false);
listView = v.findViewById(R.id.listView);
linearLayout = v.findViewById(R.id.emptyList);
mSwipeRefreshLayout = v.findViewById(R.id.swipeToRefresh);
mSwipeRefreshLayout.setColorSchemeResources(R.color.colorAccent);
mSwipeRefreshLayout.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {
@Override
public void onRefresh() {
new LoadBookmarks().execute();
}
});
new LoadBookmarks().execute();
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
Object o = listView.getAdapter().getItem(position);
if (o instanceof Map) {
Map map = (Map) o;
Intent in = new Intent(getActivity(),HomeFragment.class);
in.putExtra("url", String.valueOf(map.get(TAG_LINK)));
String.valueOf(map.get(TAG_LINK));
startActivity(in);
}
}
});
listView.setOnItemLongClickListener(new AdapterView.OnItemLongClickListener() {
@Override
public boolean onItemLongClick(AdapterView<?> adapterView, View view, int i, long l) {
Object o = listView.getAdapter().getItem(i);
if (o instanceof Map) {
Map map = (Map) o;
deleteBookmark(String.valueOf(map.get(TAG_TITLE)), String.valueOf(map.get(TAG_LINK)));
}
return true;
}
});
return v;
}
private void deleteBookmark(final String title, final String link) {
new AlertDialog.Builder(getActivity())
.setTitle("DELETE")
.setMessage("Confirm that you want to delete this bookmark?")
.setPositiveButton("YES", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialogInterface, int i) {
SharedPreferences sharedPreferences = getActivity().getSharedPreferences(PREFERENCES, Context.MODE_PRIVATE);
String jsonLink = sharedPreferences.getString(WEB_LINKS, null);
String jsonTitle = sharedPreferences.getString(WEB_TITLE, null);
if (jsonLink != null && jsonTitle != null) {
Gson gson = new Gson();
ArrayList<String> linkArray = gson.fromJson(jsonLink, new TypeToken<ArrayList<String>>() {
}.getType());
ArrayList<String> titleArray = gson.fromJson(jsonTitle, new TypeToken<ArrayList<String>>() {
}.getType());
linkArray.remove(link);
titleArray.remove(title);
SharedPreferences.Editor editor = sharedPreferences.edit();
editor.putString(WEB_LINKS, new Gson().toJson(linkArray));
editor.putString(WEB_TITLE, new Gson().toJson(titleArray));
editor.apply();
new LoadBookmarks().execute();
}
dialogInterface.dismiss();
}
}).setNegativeButton("NO", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialogInterface, int i) {
dialogInterface.dismiss();
}
}).show();
}
private class LoadBookmarks extends AsyncTask<String, String, String> {
@Override
protected void onPreExecute() {
super.onPreExecute();
}
@Override
protected String doInBackground(String... args) {
// updating UI from Background Thread
getActivity().runOnUiThread(new Runnable() {
public void run() {
SharedPreferences sharedPreferences = getActivity().getSharedPreferences(PREFERENCES, Context.MODE_PRIVATE);
String jsonLink = sharedPreferences.getString(WEB_LINKS, null);
String jsonTitle = sharedPreferences.getString(WEB_TITLE, null);
listRowData = new ArrayList<>();
if (jsonLink != null && jsonTitle != null) {
Gson gson = new Gson();
ArrayList<String> linkArray = gson.fromJson(jsonLink, new TypeToken<ArrayList<String>>() {
}.getType());
ArrayList<String> titleArray = gson.fromJson(jsonTitle, new TypeToken<ArrayList<String>>() {
}.getType());
for (int i = 0; i < linkArray.size(); i++) {
HashMap<String, String> map = new HashMap<>();
if (titleArray.get(i).length() == 0)
map.put(TAG_TITLE, "Bookmark " + (i + 1));
else
map.put(TAG_TITLE, titleArray.get(i));
map.put(TAG_LINK, linkArray.get(i));
listRowData.add(map);
}
adapter = new SimpleAdapter(getActivity(),
listRowData, R.layout.bookmark_list_row,
new String[]{TAG_TITLE, TAG_LINK},
new int[]{R.id.title, R.id.link});
listView.setAdapter(adapter);
}
linearLayout.setVisibility(View.VISIBLE);
listView.setEmptyView(linearLayout);
}
});
return null;
}
protected void onPostExecute(String args) {
mSwipeRefreshLayout.setRefreshing(false);
}
}
}
fragment_fav.xml
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="@+id/favourite"
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.v4.widget.SwipeRefreshLayout
android:id="@+id/swipeToRefresh"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="@dimen/fab_margin">
<ListView
android:id="@+id/listView"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
</android.support.v4.widget.SwipeRefreshLayout>
<LinearLayout
android:id="@+id/emptyList"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:gravity="center"
android:orientation="vertical"
android:visibility="gone">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:gravity="center"
android:text="WHOOPS"
android:textColor="#212121"
android:textSize="20sp"
android:textStyle="bold" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:gravity="center"
android:text="There are no bookmarks at the moment"
android:textColor="#212121" />
</LinearLayout>
</android.support.constraint.ConstraintLayout>
HomeFragment.java
package seacoders.abhilash.bogguru;
import android.content.Context;
import android.content.SharedPreferences;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.graphics.Bitmap;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v4.app.Fragment;
import android.support.v4.view.GravityCompat;
import android.support.v4.widget.DrawerLayout;
import android.view.KeyEvent;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.webkit.WebSettings;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.ProgressBar;
import android.widget.TextView;
import android.widget.Toast;
import com.google.gson.Gson;
import com.google.gson.reflect.TypeToken;
import java.net.URI;
import java.util.ArrayList;
import static android.content.Intent.getIntent;
public class HomeFragment extends Fragment {
WebView wv;
TextView txt;
ProgressBar pbar;
DatabaseHelper myDb;
public static final String PREFERENCES = "PREFERENCES_NAME";
String WEB_LINKS = "links";
String WEB_TITLE = "title";
String current_page_url;
public static final String TITLE = "Home";
public static HomeFragment newInstance() {
return new HomeFragment();
}
@Nullable
@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, Bundle savedInstanceState) {
//return inflater.inflate(R.layout.fragment_home, container, false);
View v=inflater.inflate(R.layout.fragment_home, container, false);
wv = (WebView)v.findViewById(R.id.webview);
wv.loadUrl("http://www.google.com");
current_page_url = wv.getUrl();
SharedPreferences sharedPreferences = getActivity().getSharedPreferences(PREFERENCES, Context.MODE_PRIVATE);
String links = sharedPreferences.getString(WEB_LINKS, null);
if (links != null) {
Gson gson = new Gson();
ArrayList<String> linkList = gson.fromJson(links, new TypeToken<ArrayList<String>>() {
}.getType());
}
FloatingActionButton fab = (FloatingActionButton)v.findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
SharedPreferences sharedPreferences = getActivity().getSharedPreferences(PREFERENCES, Context.MODE_PRIVATE);
String jsonLink = sharedPreferences.getString(WEB_LINKS, null);
String jsonTitle = sharedPreferences.getString(WEB_TITLE, null);
if (jsonLink != null && jsonTitle != null) {
Gson gson = new Gson();
ArrayList<String> linkList = gson.fromJson(jsonLink, new TypeToken<ArrayList<String>>() {
}.getType());
ArrayList<String> titleList = gson.fromJson(jsonTitle, new TypeToken<ArrayList<String>>() {
}.getType());
if (linkList.contains(current_page_url)) {
linkList.remove(wv.getUrl());
titleList.remove(wv.getTitle().trim());
SharedPreferences.Editor editor = sharedPreferences.edit();
editor.putString(WEB_LINKS, new Gson().toJson(linkList));
editor.putString(WEB_TITLE, new Gson().toJson(titleList));
editor.apply();
Snackbar.make(view, "Bookmark removed from favourites", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
} else {
linkList.add(wv.getUrl());
titleList.add(wv.getTitle().trim());
SharedPreferences.Editor editor = sharedPreferences.edit();
editor.putString(WEB_LINKS, new Gson().toJson(linkList));
editor.putString(WEB_TITLE, new Gson().toJson(titleList));
editor.apply();
Snackbar.make(view, "Bookmark added, view in favourites", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
}
} else {
ArrayList<String> linkList = new ArrayList<>();
ArrayList<String> titleList = new ArrayList<>();
linkList.add(wv.getUrl());
titleList.add(wv.getTitle());
SharedPreferences.Editor editor = sharedPreferences.edit();
editor.putString(WEB_LINKS, new Gson().toJson(linkList));
editor.putString(WEB_TITLE, new Gson().toJson(titleList));
editor.apply();
Snackbar.make(view, "Bookmark added, view in favourites", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
}
}
});
WebSettings webSettings = wv.getSettings();
webSettings.setJavaScriptEnabled(true);
pbar = (ProgressBar) v.findViewById(R.id.pg1);
txt = (TextView) v.findViewById(R.id.txtload);
wv.setWebViewClient(new MyWebViewClient());
wv.setOnKeyListener(new View.OnKeyListener()
{
@Override
public boolean onKey(View v, int keyCode, KeyEvent event)
{
if(event.getAction() == KeyEvent.ACTION_DOWN)
{
switch(keyCode)
{
case KeyEvent.KEYCODE_BACK:
if(wv.canGoBack())
{
wv.goBack();
return true;
}
break;
}
}
return false;
}
});
return v;
}
public class MyWebViewClient extends WebViewClient {
public void onReceivedError(WebView v, int errorCode, String description, String failingUrl) {
wv.loadUrl("file:///android_asset/error.html");
}
@Override
public void onPageStarted(WebView view, String url, Bitmap favicon) {
super.onPageStarted(view, url, favicon);
System.out.println("loading... please wait");
pbar.setVisibility(View.VISIBLE);
txt.setVisibility(View.VISIBLE);
}
@Override
public void onPageFinished(WebView view, String url) {
System.out.println("finished loading");
pbar.setVisibility(View.GONE);
txt.setVisibility(View.GONE);
}
}
}
AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="seacoders.abhilash.bogguru">
<uses-permission android:name="android.permission.INTERNET"></uses-permission>
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"></uses-permission>
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE"></uses-permission>
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"></uses-permission>
<uses-permission android:name="android.permission.READ_HISTORY_BOOKMARKS"></uses-permission>
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"></uses-permission>
<uses-permission android:name="android.permission.WRITE_HISTORY_BOOKMARKS"></uses-permission>
<uses-permission android:name="android.permission.WRITE_SETTINGS"></uses-permission>
<application
android:largeHeap="true"
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:roundIcon="@mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="@style/AppTheme">
<activity
android:name=".MainActivity"
android:label="@string/app_name"
android:theme="@style/AppTheme.NoActionBar">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
错误来自 listview clicklistner
在 google 上搜索 call fragment in fragment 您可以尝试以下代码
// Create fragment and give it an argument specifying the article it should show
ArticleFragment newFragment = new ArticleFragment();
Bundle args = new Bundle();
args.putInt(ArticleFragment.ARG_POSITION, position);
newFragment.setArguments(args);
FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
// Replace whatever is in the fragment_container view with this fragment,
// and add the transaction to the back stack so the user can navigate back
transaction.replace(R.id.fragment_container, newFragment);
transaction.addToBackStack(null);
// Commit the transaction
transaction.commit();
现在你的代码看起来像
new LoadBookmarks().execute();
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
Object o = listView.getAdapter().getItem(position);
if (o instanceof Map) {
Map map = (Map) o;
HomeFragment newFragment = new HomeFragment();
Bundle args = new Bundle();
args.puString("url", String.valueOf(map.get(TAG_LINK)));
newFragment.setArguments(args);
FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
transaction.replace(R.id.fragment_container, newFragment);
transaction.addToBackStack(null);
transaction.commit();
}
}
});
大家好，我使用了以下代码，我的问题已经解决了
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
Object o = listView.getAdapter().getItem(position);
if (o instanceof Map) {
final Map map = (Map) o;
Intent in = new Intent(getActivity(),HomeFragment.class);
in.putExtra("url", String.valueOf(map.get(TAG_LINK)));
System.out.println("loading url..."+String.valueOf(map.get(TAG_LINK))+" please wait");
HomeFragment.wv.post(new Runnable() {
public void run() {
HomeFragment.wv.loadUrl(String.valueOf(map.get(TAG_LINK)));
}
});
seacoders.abhilash.bogguru.MainActivity.changefrag();
}
}
});
MainActivity 中的以下代码。
private static int getItem(int i) {
return mViewPager.getCurrentItem() + i;
}
public static void changefrag() {
mViewPager.setCurrentItem(getItem(-1),true);
}