So this function is intended to remove a Unit object, and its corresponding view from a list of views. It then checks the rest of the Units, and if the previously removed one was a pre-requisite for another Unit, it recurses and removes that unit too, and so on.
The Units are removed correctly from storage, and displayed back in the pending display, but not all of the removed units' views are removed from "temp".
Edit: The function is working entirely when a maximum of one unit is in each semester, but leaves things behind otherwise.
Any insight you could offer into why this is occuring would be muchly appreciated.
void removeLinkedUnits(Unit inUnit)
{
int sem;
for(sem = semesters.size() - 1; sem >= 0; sem--) //iterate through each semester containing units
{
int unit;
for(unit = semesters.get(sem).getUnits().size() - 1; unit >= 0; unit--) //iterate through each unit in a semester
{
String[] pres = semesters.get(sem).getUnit(unit).getPrerequisites();
int i;
boolean toRemove = false;
for(i = 0; i < pres.length; i++) //Compare list of pre-requisites against removed unit.
{
if(pres[i].contains(inUnit.getUnitID()))
{
toRemove = true;
}
}
if(semesters.get(sem).getUnits().get(unit).getCorequisites().contains(inUnit.getUnitID()))
{
toRemove = true;
}
if(toRemove) //Unit relies on previously removed unit
{
Unit unitx = semesters.get(sem).getUnit(unit);
semesters.get(sem).remove(unitx);
LinearLayout temp = vertUnitLayouts.get(sem);
temp.removeViewAt(unit);
scheduledUnits.remove(unitx.getUnitID());
removeLinkedUnits(unitx);
redrawPendingSpinners();
pendingUnits.add(unitx);
LinearLayout pendingLinear = (LinearLayout) findViewById(R.id.pendingLinear);
pendingLinear.addView(makePendingView(unitx));
}
}
}
}
Figured out the problem.
temp (vertUnitsLayout) contained 2 items per Unit, not the 1 I was expecting. Misunderstood how my partner was constructing his views.
I need to use debugger more :S
Replaced:
temp.removeViewAt(unit);
With:
temp.removeViewAt(unit*2);
temp.removeViewAt(unit*2);
Related
I have a function that 'crafts' products using two String parameters.
This is working fine when I put in hard coded strings like 'Wheel' & 'Car'.
But it makes my application crash if I try to put in the exact same strings but then provided by an intent.
I already tried to give in variable into the intent instead of a hard coded string. That did not work either.
Here is some part of the code. EDIT: Error log now included
productLeft = getIntent().getStringExtra("PRODUCT LEFT");
productRight = getIntent().getStringExtra("PRODUCT RIGHT");
public void craft(String product1, String product2) {
String[][] Products = factory.getProductList();
int i = 0;
while (finalProduct == "") {
int j;
for(j = 0; j < 3; j++){
if (product1 == Products[i][0] || product2 == Products[i][0]) {
if (product1 == Products[i][1] || product2 == Products[i][1]){
finalProduct = Products[i][2];
}
}
i++;
}
}
}
Problem is with the array index obviously. The array has only four elements and you are fetching index 4, probably in for loop with i variable. But then again I also do not see the role of j in that loop, can't tell without other parts of code.
I have two lists of Default and Chrome browsers history.
I want to merge these two lists into one list.
I need to update item if I find it duplicate (is common between two lists).
So, my "BrowserRecord" class is like this:
public class BrowserRecord {
private long id;
private int bookmark;
private long created;
private long date;
private String title;
private String url;
private long visits;
#Override
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
BrowserRecord record = (BrowserRecord) o;
return url.equals(record.url);
}
#Override
public int hashCode() {
return url.hashCode();
}
// other getter setter methods
...
}
and finally, I have a method that gets browsers histories and does merging:
public List<BrowserRecord> getHistory() {
List<BrowserRecord> browserList = new ArrayList<BrowserRecord>();
// get history of default and chrome browsers
List<BrowserRecord> defaultList = getDefaultBrowserHistory();
List<BrowserRecord> chromeList = getChromeBrowserHistory();
Log.e(TAG, "=> size of Default browser:" + defaultList.size());
Log.e(TAG, "=> size of Chrome browser:" + chromeList.size());
// compare list A with B, update A item if equal item found in B and push it to tempList
for(int i=0; i<chromeList.size(); i++) {
BrowserRecord chromeBrowser = chromeList.get(i);
for(int j=0; j<defaultList.size(); j++) {
BrowserRecord defaultBrowser = defaultList.get(j);
if(chromeBrowser.equals(defaultBrowser)) {
if(chromeBrowser.getBookmark() != defaultBrowser.getBookmark())
chromeBrowser.setBookmark(1);
chromeBrowser.setVisits(chromeBrowser.getVisits() + defaultBrowser.getVisits());
}
}
browserList.add(chromeBrowser);
}
// compare list B with A, jump if equal item found in A, push to tempList if item not found
for(int i=0; i<defaultList.size(); i++) {
BrowserRecord defaultBrowser = defaultList.get(i);
boolean found = false;
for(int j=0; j<chromeList.size(); j++) {
BrowserRecord chromeBrowser = chromeList.get(j);
if(defaultBrowser.equals(chromeBrowser)) {
found = true;
break;
}
}
if(!found)
browserList.add(defaultBrowser);
}
Log.e(TAG, "=> size of final browser:" + browserList.size());
return browserList;
}
I have tested this method and is working fine. Since my history records on mobile device after 3 years didn't exceed more than 200 records on one list and 150 for others, I assume something similar is happening for other users. But I'm sure is not optimum way.
What do you recommend?
any suggestion would be appreciated. Thanks.
Not sure I understand correctly, but it seems like what you're trying to do is, given both lists, create a final list which will contain all of the elements from both lists, removing any duplicates.
If this is the case, then take a look at Java's TreeSet class. If you iterate over all of the elements from both your lists and insert them into a TreeSet, you will basically get the result you're looking for. You can then use an Iterator to create an ArrayList containing all of the non-duplicate items from both your lists. As a side-effect of using a TreeSet, they will ordered (you can also use either a HashSet if you don't care about the order or a LinkedHashSet if you want to preserve the order of insertion).
I have list of integer IDs. Lets say this list is ArrayList<Integer> or int[], it doesn't matter. I have another ArrayList<Obj> that contains the objects with the same ids like in the first list, but they are ordered in different order.
I want to order the objects in the second list in the order as the ids in the first list.
EXAMPLE:
FIRST LIST: { 1, 5, 4, 8, 6 }
SECOND LIST: { Obj[id=5], Obj[id=8], Obj[id=6], Obj[id=1], Obj[id=4] }
RESULT LIST: { Obj[id=1], Obj[id=5], Obj[id=4], Obj[id=8], Obj[id=6] }
Can someone tell me an (efficient) way to do this?
I would suggest using a map:
Map<Integer, Obj> map = new HashMap<Integer, Obj>(secondList.size() * 2);
for (final Obj obj : secondList) {
map.put(obj.id, obj);
}
for (int i = 0; i < secondList.size(); i++) {
secondList.set(i, map.get(firstList.get(i)));
}
This runs in O(n), which IMHO is pretty much the best you can get.
A/ Create a matching id index list, such as:
1 -> 0
5 -> 1
4 -> 2
8 -> 3
6 -> 4
That's a reversed reference of your first list. It indicates the position of each id. A SparseIntArray is a good way of doing it:
SparseIntArray ref = new SparseIntArray();
for (int i = 0; i < firstList.size(); i++) {
ref.append(firstList.get(i), i);
}
Then you need to sort your second list using a Comparator that uses the id of the Object and the ref table:
Collections.sort(secondList, new Comparator<Obj>() {
public int compare(Obj t1, Obj t2) {
return ref.get(t1.id) - ref.get(t2.id);
}
});
I was in the middle of writing Etienne's answer when he posted it, so just for fun here's an O(N^2) solution with a smaller constant factor that doesn't create any objects:
int[] first = { 1, 5, 4, 8, 6 };
Obj[] second = { Obj[id=5], Obj[id=8], Obj[id=6], Obj[id=1], Obj[id=4] };
int i = 0;
while(i < second.length) {
int ind = -1;
for(int j=0;j<first.length;j+=1) {
if(first[j] == second[i].id) {
ind = j;
break;
}
}
if(ind == -1) break; //Bad news
if(ind == i) {
i += 1;
} else {
Obj temp = second[i];
second[i] = second[ind];
second[ind] = temp;
}
}
Obviously the creation of second[] is pseudocode, but the rest will work if the arrays are equal length. I think this will be a little bit faster than Etienne's for very small data sets, but you'd have to profile both answers.
I am getting an unusual result when attempting to place a value in an array.
I have an array table[] of a simple class result{ int score, long time, string ID}
Intention is to have a sort of leader board.
My code happily finds the correct place to insert a new score if it is in the top 10.
int ix = 0;
int jx = 10; //
while ( ix < jx )
{
if (points > sTable[ix].points)
{
// score is higher move records down
for (jx = mNumRecords - 1; jx >ix ; jx--)
{
sTable[jx] = sTable[jx -1];
}
//now add new score
sTable[ix].score = score; // all good until here
sTable[ix].time = time;
}
ix++;
}
Problem is that when I try to insert the score using sTable[ix].score = score;
The value gets written to sTable[ix].score and also sTable[ix +1].score.
It is repeatable, it occurs at any value of ix, I have single stepped through the code and as far as I can tell the command only executes once.
Has anyone seen this before?
That because you copied the object reference to the next element in the array. You should copy the values, or create a new object:
Option A:
// score is higher move records down
for (jx = mNumRecords - 1; jx >ix ; jx--)
{
sTable[jx].time = sTable[jx -1].time;
sTable[jx].score = sTable[jx -1].score;
}
//now add new score
sTable[ix].score = score; // all good until here
sTable[ix].time = time;
Option B:
for (jx = mNumRecords - 1; jx >ix ; jx--)
{
sTable[jx] = sTable[jx -1];
}
sTable[ix] = new Result(score, time, ""); // Or however you construct the object
I'm developping an app which constantly needs to show the results to the user in a TextView like some sort of log.
The app works nicely and it shows the results in the TextView but as long as it keeps running and adding lines the app gets slower and crashes because of the character length of the TextView.
I would like to know if the android API provides any way to force a TexView to automatically delete the oldest lines that were introduced in order to make room for the new ones.
I had the same problem. I just resolved it.
The trick is to use the getEditableText() method of TextView. It has a replace() method, even a delete() one. As you append lines in it, the TextView is already marked as "editable", which is needed to use getEditableText(). I have something like that:
private final static int MAX_LINE = 50;
private TextView _debugTextView; // Of course, must be filled with your TextView
public void writeTerminal(String data) {
_debugTextView.append(data);
// Erase excessive lines
int excessLineNumber = _debugTextView.getLineCount() - MAX_LINE;
if (excessLineNumber > 0) {
int eolIndex = -1;
CharSequence charSequence = _debugTextView.getText();
for(int i=0; i<excessLineNumber; i++) {
do {
eolIndex++;
} while(eolIndex < charSequence.length() && charSequence.charAt(eolIndex) != '\n');
}
if (eolIndex < charSequence.length()) {
_debugTextView.getEditableText().delete(0, eolIndex+1);
}
else {
_debugTextView.setText("");
}
}
}
The thing is, TextView.getLineCount() returns the number of wrapped lines, and not the number of "\n" in the text... It is why I clear the whole text if I reach the end of the text while seeking the lines to delete.
You can do that differently by erasing a number of characters instead of erasing a number of lines.
This solution keeps track of the log lines in a list and overwrites the textview with the contents of the list on each change.
private List<String> errorLog = new ArrayList<String>();
private static final int MAX_ERROR_LINES = 70;
private TextView logTextView;
public void addToLog(String str) {
if (str.length() > 0) {
errorLog.add( str) ;
}
// remove the first line if log is too large
if (errorLog.size() >= MAX_ERROR_LINES) {
errorLog.remove(0);
}
updateLog();
}
private void updateLog() {
String log = "";
for (String str : errorLog) {
log += str + "\n";
}
logTextView.setText(log);
}
Here is an example that adds lines to an output log limited by the set max lines. The scrollview will auto scroll to the bottom after every line is added. This example work purely with the contents of the TextView so it doesn't have the need for a separate data collection.
Add the following to your activity xml:
<ScrollView
android:id="#+id/scrollView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:scrollbars="vertical" >
<TextView
android:id="#+id/textViewOutput"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:maxLines="1000" />
</ScrollView>
In your activity add the following code:
private static final int MAX_OUTPUT_LINES = 50;
private static final boolean AUTO_SCROLL_BOTTOM = true;
private TextView _textViewOutput;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
_textViewOutput = (TextView) findViewById(R.id.textViewOutput);
}
//call to add line(s) to TextView
//This should work if either lineText contains multiple
//linefeeds or none at all
private void addLinesToTextView(String lineText) {
_textViewOutput.append(lineText);
removeLinesFromTextView();
if(AUTO_SCROLL_BOTTOM)
_scrollView.post(new Runnable() {
#Override
public void run() {
_scrollView.fullScroll(ScrollView.FOCUS_DOWN);
}
});
}
// remove leading lines from beginning of the output view
private void removeLinesFromTextView() {
int linesToRemove = _textViewOutput.getLineCount() - MAX_OUTPUT_LINES;
if (linesToRemove > 0) {
for (int i = 0; i < linesToRemove; i++) {
Editable text = _textViewOutput.getEditableText();
int lineStart = _textViewOutput.getLayout().getLineStart(0);
int lineEnd = _textViewOutput.getLayout().getLineEnd(0);
text.delete(lineStart, lineEnd);
}
}
}
The TextView shows what you set via setText() method. So this sounds to me like you should cut down the input you provide.
To empty the TextView, you can do setText("");
Kotlin answer of Vincent Hiribarren
fun write_terminal_with_limit(data: String?, limit:Int)
{
log_textView.append(data)
val nb_line_to_del: Int = log_textView.lineCount - limit
// Erase excessive lines
if (nb_line_to_del > 0)
{
var end_of_line_idx = -1
val char_seq: CharSequence = log_textView.text
for (i in 0 until nb_line_to_del)
{
do
{
end_of_line_idx++
}
while (end_of_line_idx < char_seq.length && char_seq[end_of_line_idx] != '\n')
}
if (end_of_line_idx < char_seq.length)
{
log_textView.editableText.delete(0, end_of_line_idx + 1)
}
else
{
log_textView.text = ""
}
}
}
I made personnal adjustment...
I think you are using TextView.append(string) then it will add to old text.
If you are setting using setText it will replace the old text
This is an old one, but I just found looking for a solution to my own problem.
I was able to remove all TextViews from a LinearLayout using nameoflayout.removeAllViews();
There is another method that will allow you to remove views from specified places in the layout using ints, it's: nameoflayout.removeViews(start, count); so I'm sure you could create a time out for how long textviews remain visible.
No, android API doesn't provide any functionally that delete oldest lines from textview automatically till API level 25. you need to do it logically.
Try to write a function that takes an old string on TextView and add new string to it, then get substring last strings that TextView capable. And set it to TextView. Something like this:
String str = textview.getText();
str += newstring;
int ln = str.length();
ln = ln-250;
if (ln<0) ln=0;
str = str.substring(ln);
textview.setText(str);
reference Vincent Hiribarren answer.
make it simple-->
TextView _debugTextView;
//if excess 20 lines keep new 200 chars
if(_debugTextView.getLineCount() >20) _debugTextView.getEditableText().delete(0,_debugTextView.getText().length()-200);