SoloPilot SoloPilot - 6 months ago 132
Android Question

Android: EditText focus jumps to another inside ScrollView

I have multiple fragments horizontally adjacent using a ViewPager. Each fragment has a ScrollView that contains a table with many EditText views. When I click on a EditText, it gains focus and then loses it to some other EditText in the leftmost fragment. Sometimes the focus switch happens immediately, sometimes while I am typing into a EditText. Usually, the topmost EditText in the leftmost fragment steals focus.

I don't see the problem when a EditText in the leftmost fragment is clicked, even if it is not the topmost one. Its like Android doesn't like focusing on a TextView that is not along the left edge. Does this sound familiar?

I have unsuccessfully tried overriding the findFocus() method in ScrollView as suggested by Skip in randomly-jumping. The source code attached is huge, but it may be useful to others...

package com.example.slideViewPager;

import java.util.ArrayList;

import com.example.slideViewPager.R;

import android.content.Context;
import android.graphics.Color;
import android.graphics.Typeface;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.view.ViewPager;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.view.inputmethod.EditorInfo;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.ScrollView;
import android.widget.TableLayout;
import android.widget.TableRow;
import android.widget.TextView;

public class SlideViewPager extends FragmentActivity {
private static Context g;
private static ArrayList<String> pages;
private static int currentItem; // restore page position after tilt
private static int[] scrollStateY;
private static NotesViewFragment[] fragmentArray;
private static int id; // to create unique view ids

@Override
public void onCreate(Bundle savedInstanceState) {
g = getApplicationContext();
setContentView(R.layout.activity_slide_view_pager);
pages = new ArrayList<String>();
for (int i = 0; i < 4; ++i)
pages.add(Integer.toString(i));

if (savedInstanceState == null) {
currentItem = 0;
scrollStateY = new int[pages.size()]; // assume all 0s
id = 0;
}
else {
currentItem = savedInstanceState.getInt("currentItem");
scrollStateY = savedInstanceState.getIntArray("scrollStateY");
id = savedInstanceState.getInt("id");
System.out.println("Notes onCreate RESTORE: currentItem="+currentItem+"; id="+id);
}

fragmentArray = new NotesViewFragment[pages.size()];
System.out.println("onCreate: start");
super.onCreate(savedInstanceState);
ViewPager viewPager = (ViewPager) findViewById(R.id.viewpager);
NotesPagerAdapter pagerAdapter = new NotesPagerAdapter(getSupportFragmentManager());
viewPager.setAdapter(pagerAdapter);
viewPager.setCurrentItem(currentItem);
viewPager.setOnPageChangeListener(onPageChangeListener);
System.out.println("onCreate: done");
}

@Override
public void onSaveInstanceState(Bundle bundle) {
System.out.println("Notes: onSaveInstanceState: currentItem="+currentItem);
super.onSaveInstanceState(bundle);
bundle.putInt("currentItem", currentItem);
bundle.putIntArray("scrollStateY", scrollStateY);
bundle.putInt("id", id);
}

public void onBackPressed() {
System.out.println("Notes: onBackPressed: currentItem="+currentItem);
super.onBackPressed();
}

/////////////////////////////////////////////////////////////////
public static class NotesPagerAdapter extends FragmentPagerAdapter {

public NotesPagerAdapter(FragmentManager fm) {
super(fm);
System.out.println("NotesPagerAdapter: this="+this);
}

@Override
public Fragment getItem(int position) {
String pageNum = pages.get(position);
NotesViewFragment notesViewFragment = NotesViewFragment.initialize(pageNum, position); // create new fragment
System.out.println("NotesPagerAdapter: getItem: CREATED position:"+position+" = page:"+pageNum+"; fragment="+notesViewFragment);
return notesViewFragment;
}

@Override
public int getCount() {
return pages.size();
}

// nothing being done here
@Override
public void destroyItem(ViewGroup container, int position, Object object) {
System.out.println("NotesPagerAdapter: destroyItem position="+position);
super.destroyItem(container, position, object);
}

@Override
public float getPageWidth(int position) {
System.out.println("NotesPagerAdapter: getPageWidth position="+position);
return (1.0f/2); // vary # pages/view
}
}

//////////////////////////////////////////////////////
public static class NotesViewFragment extends Fragment {
private int position; // needed to save scrollY into scrollStateY[]
private String pageNum; // index
private ScrollView itemScrollView;

public NotesViewFragment() {
super();
System.out.println("NotesViewFragment: new this:"+this);
}

public static NotesViewFragment initialize(String page, int position) {
NotesViewFragment notesViewFragment = new NotesViewFragment();
System.out.println("NotesViewFragment: initialize: this:"+notesViewFragment+"; page: "+page+"; position="+position);
Bundle args = new Bundle();
args.putString("pageNum", page);
args.putInt("position", position);
scrollStateY[position] = 0; // start at top
notesViewFragment.setArguments(args);
return notesViewFragment;
}

@Override
public void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
System.out.println("NotesViewFragment: onSaveInstanceState this:"+this+"; page: "+pageNum+"; scrollView="+itemScrollView);
// itemScrollView will be null occasionally (attached but not createViewed)
if (itemScrollView != null)
scrollStateY[position] = itemScrollView.getScrollY();
outState.putString("pageNum", pageNum);
}

@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Bundle args = getArguments();
if (args != null) {
pageNum = args.getString("pageNum");
position = args.getInt("position");
fragmentArray[position] = this;
System.out.println("NotesViewFragment: onCreate: this:"+this+"; page: "+pageNum+"; position="+position+"; yPos="+scrollStateY[position]);
}
else // should not happen
System.out.println("NotesViewFragment: onCreate: NO ARGS !!! this:"+this);
}

public void onDestroyView() {
super.onDestroyView();
if (itemScrollView != null) // could be null if not createViewed
scrollStateY[position] = itemScrollView.getScrollY();

System.out.println("NotesViewFragment: onDestroyView: "+pageNum+" this="+this+"; scrollY="+scrollStateY[position]);
}

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
if (savedInstanceState != null) { // config change happened
pageNum = savedInstanceState.getString("pageNum");
System.out.println("NotesViewFragment: onCreateView: RESTORED "+pageNum+" this="+this+"; yPos="+scrollStateY[position]);
}
else
System.out.println("NotesViewFragment: onCreateView: "+pageNum+"; this="+this);

// Inflate the layout containing a title and body text.
ViewGroup rootView = (ViewGroup) inflater.inflate(R.layout.fragment_screen_slide_page, container, false);
TableLayout itemNotesTable = (TableLayout) rootView.findViewById(R.id.tableLayoutNotes);
TextView itemTitle = (TextView) rootView.findViewById(R.id.textViewTitle);
itemScrollView = (ScrollView) rootView.findViewById(R.id.scroll_form);
itemTitle.setText("Team "+pageNum);

for (int i = 0; i < 12; ++i) {
TableRow tr = new TableRow(g);
tr.setId(++id);

ImageView itemThumbnail = new ImageView(g);
itemThumbnail.setId(++id);
itemThumbnail.setImageResource(R.drawable.notes); // set icon
tr.addView(itemThumbnail);

LinearLayout ll = new LinearLayout(g);
ll.setId(++id);
ll.setOrientation(LinearLayout.VERTICAL);
String text = " Team "+pageNum;
ll.addView(makeTextItem(text, false));

TextView textView;
if ((id % 2) == 0) { // make some entries editable
textView = new EditText(g);
textView.setFocusable(true);
textView.setFocusableInTouchMode(true);
textView.setImeOptions(EditorInfo.IME_FLAG_NO_ENTER_ACTION);
textView.setOnFocusChangeListener(onFocusChangeListener);
}
else
textView = new TextView(g);

textView.setId(++id);
String str = "Line "+i+" is blah blah blah and more blah blah blah";
textView.setText(str);
textView.setTextColor(Color.BLACK);
textView.setTextSize(16);
textView.setPadding(2, 2, 2, 2); // start, top, end, bottom
ll.addView(textView);
tr.addView(ll);
itemNotesTable.addView(tr);
tr.setOnClickListener(noteClicked); // make everything in table row clickable
}

if (scrollStateY[position] != 0) {
itemScrollView.post(new Runnable() {
public void run() {
itemScrollView.scrollTo(0, scrollStateY[position]);
}
});
}
return rootView;
}

// called from fillNotes
private static TextView makeTextItem(String label, boolean bold) {
TextView item = new TextView(g);
item.setId(++id);
item.setText(label);
item.setTextColor(Color.BLACK);
item.setTextSize(16);
if (bold)
item.setTypeface(null, Typeface.BOLD);
return item;
}
}

// listens for horizontal page scrolls
ViewPager.OnPageChangeListener onPageChangeListener = new ViewPager.SimpleOnPageChangeListener() {
@Override
public void onPageSelected(int position) {
System.out.println("onPageChangeListener: leaving page:"+currentItem+"; for page: "+position);
currentItem = position;
}
};

static View.OnFocusChangeListener onFocusChangeListener = new View.OnFocusChangeListener() {

@Override
public void onFocusChange(View view, boolean hasFocus) {
System.out.println("onFocusChangeListener: "+hasFocus+"; "+view);
if (! hasFocus) {
EditText editText = (EditText) view;
String text = editText.getText().toString();
System.out.println("onFocusChangeListener: "+text);
}
}
};

static OnClickListener noteClicked = new OnClickListener() {
public void onClick(View tr) {
for (View parent = tr; parent != null; parent = (View) parent.getParent()) {
for (NotesViewFragment fragment : fragmentArray)
if (fragment != null && fragment.itemScrollView == parent) {
System.out.println("noteClicked: page: "+fragment.pageNum);
return;
}
}
}
};
}


There are a couple of XML files: fragment_screen_slide_page.xml ..........

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/content"
android:layout_width="match_parent"
android:layout_height="match_parent">

<TextView
android:id="@+id/textViewTitle"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:text=""
android:textAppearance="?android:attr/textAppearanceLarge" />

<View
android:id="@+id/separator"
android:layout_width="fill_parent"
android:layout_height="1dip"
android:layout_alignParentRight="true"
android:layout_marginTop="4dp"
android:layout_below="@+id/textViewTitle"
android:background="#888888" />

<ScrollView
android:id="@+id/scroll_form"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_below="@+id/separator" >

<TableLayout
android:id="@+id/tableLayoutNotes"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:stretchColumns="1" >
</TableLayout>
</ScrollView>
</RelativeLayout>


and activity_slide_view_pager.xml ----------

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"

android:descendantFocusability="beforeDescendants"
android:focusableInTouchMode="true"
tools:context=".Page" >

<android.support.v4.view.ViewPager
android:id="@+id/viewpager"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
</RelativeLayout>

Answer

Focus is changing to the leftmost fragment because that fragment is the current item of the ViewPager. You might try to use setCurrentItem(item) to set the current item to the other fragment (when the user clicks on it) so the left one doesn't steal focus.

This is happening because at the end of the populate() function of the ViewPager it will always give focus to a view that is in the current item. You could also fix this issue by copying the ViewPager source and changing this code to allow any fragment which is on the screen to have a child with focus.

Change this:

if (hasFocus()) {
    View currentFocused = findFocus();
    ItemInfo ii = currentFocused != null ? infoForAnyChild(currentFocused) : null;
    if (ii == null || ii.position != mCurItem) {
        for (int i = 0; i < getChildCount(); i++) {
            View child = getChildAt(i);
            ii = infoForChild(child);
            if (ii != null && ii.position == mCurItem) {
                if (child.requestFocus(FOCUS_FORWARD)) {
                    break;
                }
            }
        }
    }
}

To something like this:

if (hasFocus()) {
    View currentFocused = findFocus();
    ItemInfo ii = currentFocused != null ? infoForAnyChild(currentFocused) : null;
    if (ii == null || !infoIsOnScreen(ii)) {
        for (int i = 0; i < getChildCount(); i++) {
            View child = getChildAt(i);
            ii = infoForChild(child);
            if (ii != null && infoIsOnScreen(ii)) {
                if (child.requestFocus(FOCUS_FORWARD)) {
                    break;
                }
            }
        }
    }
}

public boolean infoIsOnScreen(ItemInfo info) {
    // Code to determine if the view is on the screen using ii.offset etc.
}