How to update ListView in Drag-Sort ListView?

Question

I have an implementation of Drag-Sort ListView (DSLV) and LazyList together in my project, I load the LazyList and Drag-Sort ListView demos from github, then integrate and modify as per my requirement.

I use DSLV to drag and sort ListView and LazyList elements to display the image from the URL, I just implement the "Basic use of the playground" from DSLV to drag and sort,

I have an implementation in TestBedDSLV.java, but the problem is that when I search for content from a list, but I can’t update the list, I tried the notifyDataSetChanged method, but it doesn’t work, as a rule, we create a new adapter and pass it to listview like lv.setAdapter (adapter), but here they just install the ListAdapter, so we can't do lv.setAdapter (adapter)

TestBedDSLV.java

package com.mobeta.android.demodslv; import android.os.Bundle; import android.support.v4.app.Fragment; import android.support.v4.app.FragmentActivity; import android.text.Editable; import android.text.TextWatcher; import android.view.Menu; import android.view.MenuInflater; import android.widget.Button; import android.widget.EditText; import com.mobeta.android.dslv.DragSortController; import com.mobeta.android.dslv.DragSortListView; public class TestBedDSLV extends FragmentActivity { private int mNumHeaders = 0; private int mNumFooters = 0; private int mDragStartMode = DragSortController.ON_DOWN; private boolean mRemoveEnabled = false; private int mRemoveMode = DragSortController.FLING_RIGHT_REMOVE; private boolean mSortEnabled = true; private boolean mDragEnabled = true; private String mTag = "dslvTag"; Button search; EditText search_customer; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.test_bed_main); search = (Button) findViewById(R.id.btn_search); search_customer = (EditText) findViewById(R.id.search_product); search_customer.addTextChangedListener(new TextWatcher() { @Override public void onTextChanged(CharSequence s, int start, int before, int count) { // here is logic for refresh the list View } @Override public void beforeTextChanged(CharSequence s, int start, int count, int after) { } @Override public void afterTextChanged(Editable s) { } }); if (savedInstanceState == null) { getSupportFragmentManager().beginTransaction() .add(R.id.test_bed, getNewDslvFragment(), mTag).commit(); } } @Override public boolean onCreateOptionsMenu(Menu menu) { MenuInflater inflater = getMenuInflater(); inflater.inflate(R.menu.mode_menu, menu); return true; } private Fragment getNewDslvFragment() { DSLVFragmentClicks f = DSLVFragmentClicks.newInstance(mNumHeaders, mNumFooters); f.removeMode = mRemoveMode; f.removeEnabled = mRemoveEnabled; f.dragStartMode = mDragStartMode; f.sortEnabled = mSortEnabled; f.dragEnabled = mDragEnabled; return f; } } 

DSLVFragmentClicks.java

 package com.mobeta.android.demodslv; import android.view.View; import android.widget.AdapterView; import android.widget.ListView; import android.os.Bundle; import android.widget.Toast; public class DSLVFragmentClicks extends DSLVFragment { public static DSLVFragmentClicks newInstance(int headers, int footers) { DSLVFragmentClicks f = new DSLVFragmentClicks(); Bundle args = new Bundle(); args.putInt("headers", headers); args.putInt("footers", footers); f.setArguments(args); return f; } AdapterView.OnItemLongClickListener mLongClickListener = new AdapterView.OnItemLongClickListener() { @Override public boolean onItemLongClick(AdapterView<?> arg0, View arg1, int arg2, long arg3) { String message = String.format("Long-clicked item %d", arg2); Toast.makeText(getActivity(), message, Toast.LENGTH_SHORT).show(); return true; } }; @Override public void onActivityCreated(Bundle savedState) { super.onActivityCreated(savedState); ListView lv = getListView(); lv.setOnItemClickListener(new AdapterView.OnItemClickListener() { @Override public void onItemClick(AdapterView<?> arg0, View arg1, int arg2, long arg3) { String message = String.format("Clicked item %d", arg2); Toast.makeText(getActivity(), message, Toast.LENGTH_SHORT).show(); } }); lv.setOnItemLongClickListener(new AdapterView.OnItemLongClickListener() { @Override public boolean onItemLongClick(AdapterView<?> arg0, View arg1, int arg2, long arg3) { String message = String.format("Long-clicked item %d", arg2); Toast.makeText(getActivity(), message, Toast.LENGTH_SHORT).show(); return true; } }); } } 

DSLVFragment.java

 package com.mobeta.android.demodslv; import java.util.ArrayList; import java.util.Arrays; import android.os.Bundle; import android.support.v4.app.ListFragment; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.ArrayAdapter; import com.mobeta.android.dslv.DragSortController; import com.mobeta.android.dslv.DragSortListView; public class DSLVFragment extends ListFragment { ArrayAdapter<String> adapter; private String[] array; public static ArrayList<String> list; private DragSortListView.DropListener onDrop = new DragSortListView.DropListener() { @Override public void drop(int from, int to) { if (from != to) { String item = adapter.getItem(from); adapter.remove(item); adapter.insert(item, to); } } }; private DragSortListView.RemoveListener onRemove = new DragSortListView.RemoveListener() { @Override public void remove(int which) { adapter.remove(adapter.getItem(which)); } }; protected int getLayout() { return R.layout.dslv_fragment_main; } /** * Return list item layout resource passed to the ArrayAdapter. */ protected int getItemLayout() { return R.layout.list_item_handle_right; } private DragSortListView mDslv; private DragSortController mController; public int dragStartMode = DragSortController.ON_DOWN; public boolean removeEnabled = false; public int removeMode = DragSortController.FLING_RIGHT_REMOVE; public boolean sortEnabled = true; public boolean dragEnabled = true; public static DSLVFragment newInstance(int headers, int footers) { DSLVFragment f = new DSLVFragment(); Bundle args = new Bundle(); args.putInt("headers", headers); args.putInt("footers", footers); f.setArguments(args); return f; } public DragSortController getController() { return mController; } /** * Called from DSLVFragment.onActivityCreated(). Override to set a different * adapter. */ public void setListAdapter() { array = getResources().getStringArray(R.array.jazz_artist_names); list = new ArrayList<String>(Arrays.asList(array)); adapter = new ArrayAdapter<String>(getActivity(), getItemLayout(), R.id.text, list); setListAdapter(adapter); } /** * Called in onCreateView. Override this to provide a custom * DragSortController. */ public DragSortController buildController(DragSortListView dslv) { DragSortController controller = new DragSortController(dslv); controller.setDragHandleId(R.id.drag_handle); controller.setClickRemoveId(R.id.click_remove); controller.setRemoveEnabled(removeEnabled); controller.setSortEnabled(sortEnabled); controller.setDragInitMode(dragStartMode); controller.setRemoveMode(removeMode); return controller; } /** Called when the activity is first created. */ @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { mDslv = (DragSortListView) inflater.inflate(getLayout(), container, false); mController = buildController(mDslv); mDslv.setFloatViewManager(mController); mDslv.setOnTouchListener(mController); mDslv.setDragEnabled(dragEnabled); return mDslv; } @Override public void onActivityCreated(Bundle savedInstanceState) { super.onActivityCreated(savedInstanceState); mDslv = (DragSortListView) getListView(); mDslv.setDropListener(onDrop); mDslv.setRemoveListener(onRemove); Bundle args = getArguments(); int headers = 0; int footers = 0; if (args != null) { headers = args.getInt("headers", 0); footers = args.getInt("footers", 0); } setListAdapter(); } } 

test_bed_main.xml

 <?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="fill_parent" android:layout_height="fill_parent" android:orientation="vertical" > <LinearLayout android:id="@+id/search_lay" android:layout_width="fill_parent" android:layout_height="wrap_content" android:focusable="true" android:focusableInTouchMode="true" android:orientation="horizontal" > <EditText android:id="@+id/search_product" android:layout_width="fill_parent" android:layout_height="wrap_content" android:layout_marginBottom="2dp" android:layout_marginLeft="5dp" android:layout_marginTop="2dp" android:layout_weight="1" android:background="@drawable/search_back" android:hint="Enter Firstname" android:imeOptions="actionSearch" android:inputType="text" android:paddingBottom="2dp" android:paddingLeft="5dp" android:paddingTop="2dp" android:visibility="visible" /> <Button android:id="@+id/btn_search" android:layout_width="fill_parent" android:layout_height="wrap_content" android:layout_marginLeft="5dp" android:layout_marginRight="5dp" android:layout_weight="2.5" android:text="CANCEL" android:textColor="#155280" android:textSize="14sp" android:textStyle="bold" android:visibility="visible" /> </LinearLayout> <FrameLayout android:id="@+id/test_bed" android:layout_width="fill_parent" android:layout_height="fill_parent" /> <!-- We will add the DSLVFragment inside the FrameLayout in code --> </LinearLayout> 

and another require class can be loaded from the github link above .....

Answer 1

In fact, if you see your code closed, there is a method that you specified

 public void setListAdapter() { array = getResources().getStringArray(R.array.jazz_artist_names); list = new ArrayList<String>(Arrays.asList(array)); adapter = new ArrayAdapter<String>(getActivity(), getItemLayout(), R.id.text, list); setListAdapter(adapter); } 

So, as you said: "Usually we create a new adapter and pass it to listview as lv.setAdapter (adapter), but here they just install the ListAdapter, so we can not do lv.setAdapter (adapter)"

Can't you easily do this by simply creating an array based on your search and setting it up as code?

 list = new ArrayList<String>(Arrays.asList(array)); adapter = new ArrayAdapter<String>(getActivity(), getItemLayout(), R.id.text, list); setListAdapter(adapter); 

EDIT: I think you are asking the wrong question. Your main problem is how to communicate between activity and fragments ... since your search function is in action and the list is in fragment. Therefore, you need to configure an interface that basically passes the search string to your fragment, and there you can create an array and configure it the same way as now.

Read this question and answer. In the answer you will find one similar approach when transferring data between activity and fragment.

Edit 2: Your main problem is to exchange information with activity per fragment for this. Make your interface in your activities as follows:

  public interface FragmentCommunicator{ public void passDataToFragment(String someValue); } then call the interface at your text change listener..for example FragmentCommunicator mfragmentCommunicator; //your onCreate function { //your textchangelistenr { onTextChanged call if(mfragmentCommunicator != null) mfragmentCommunicator.passDataToFragment(Pass your string here) } then make your fragement implement this interface like public class someFragment extends Fragment implements FragmentCommunicator { //this is your rest of the fragment @Override public void passDataToFragment(String somevalue) { //This function will get fired each time your text is changed since in your activity you are calling this same function in your textchange listener. the String somevalue will be the string that you passed from your activity } //rest of the code . . . //Don't forget to initialize your interface in fragment itself. Do this in your onAttach like this @Override public void onAttach(Activity activity){ super.onAttach(activity); context = getActivity(); ((MainActivity)context).fragmentCommunicator = this; } } } 

You can refer to this link for any further clarification. Check only implementation of FragmentCommunicator

Answer 2

If you use the array as the base arraylist for the adapter, just update this array and call adaptater.notifyDataSetChanged (). This is sure to update DSLV, as I used the same approach in one of my projects.