Develop Reference

Finding an element within the same TableRow

I'm trying to create a function that pulls together information that is currently scattered around different parts of my project.
As part of this task, I have a layout file with something like the following content... basically a set of rows, with each row having a label (TextView) and a UI element (e.g. CheckBox, Spinner or EditText) to collect information from the user:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
style="#style/MyLinearLayout.Section"
android:id="#+id/section_pressure" >
<TableLayout style="#style/MyTableLayout"
android:id="#+id/table_pressure" >
<TableRow style="#style/MyTableRow" >
<TextView
style="#style/MyTextView.Label.WithHelp"
android:tag="label_show"
android:text="#string/label_show" />
<CheckBox
style="#style/MyCheckBox"
android:id="#+id/pressure" />
</TableRow>
<TableRow style="#style/MyTableRow" >
<TextView
style="#style/MyTextView.Label.WithHelp"
android:tag="label_unit"
android:text="#string/label_unit" />
<Spinner
style="#style/MySpinnerStyle"
android:id="#+id/pressureUnit" />
</TableRow>
</TableLayout>
</LinearLayout>
I already have an array of all the android:id values for the UI elements, and from that I want to generate another array of the corresponding android:text labels.
e.g. from R.id.pressureUnit I want to find the associated R.string.label_unit from that TableRow, so that I have a central record of what label is used for each UI element... currently that information is scattered across lots of different layout files.
Is this possible programmatically?

From what I understand you want to find #string resource ID of a sibling view of a given view.
Assuming you have the xml file already inflated, you can do the following:
private int getSiblingStringId(#IdRes int viewId) {
View uiElement = findViewById(viewId);
ViewGroup parent = (ViewGroup) uiElement.getParent();
// iterate through the siblings
for (int i = 0; i < parent.getChildCount(); i++) {
View view = parent.getChildAt(i);
if (view instanceof TextView) {
String value = ((TextView) view).getText().toString();
// found
return getStringIdFromValue(value);
}
}
throw new IllegalArgumentException("no TextView sibling for " + viewId);
}
private int getStringIdFromValue(String value) {
// get all fields using reflection
Field[] fields = R.string.class.getDeclaredFields();
for (Field field : fields) {
int stringResId = getResources().getIdentifier(field.getName(), "string", getPackageName());
String s = getString(stringResId);
if (s.equals(value)) return stringResId;
}
throw new IllegalArgumentException("no matching string for " + value);
}
The above code will work inside an activity. You might need to modify it a bit for other classes. (You will need to call findViewById, getResources and getString)

Well, I would set an ID to each table row. Then, programmatically get every child view under each row by iterating over the row's children. From there, you can easily manipulate every view by simply determining which one are you at by using instanceof. But, let's assume you cannot change this, you can still be doing it but it might not be efficient.
Since I don't really know the structure of your array of ids, I just assume its an array of integers called uiIds. Then, you would have to do something like
TableLayout layout = findViewById(R.id.table_pressure);
TableRow tr = null;
View rowChild = null;
TextView tv = null;
View secondaryView = null;
int tableChildCount = layout.getChildCount();
int rowChildCount = 0;
// Since I don't really know the structure of your array of ids,
// I just assume its an array of integers called uiIds
//This will contain the corresponding text strings of every textview
List<String> textLabels = Arrays.asList(new String[uiIds.length]);
// Go over all the rows on your table
for (int i = 0; i < tableChildCount; i++) {
// I'm assuming that you only have rows as the children of your table
tr = (TableRow) layout.getChildAt(i); //This is the row
rowChildCount = tr.getChildCount();
tv = null;
secondaryView = null;
// Now go over all the children of the current row i
for (int j = 0; j < rowChildCount; j++) {
// Here I'm also assuming you only have two children on every row
rowChild = getChildAt(j);
// At this point, the view v could be any type of the ones you have
// used. Since we are interested in TextView simply do an instanceof
if ( rowChild instanceof TextView ) {
tv = (TextView) v;
} else {
// This is the other view in the row. The ones from which you alreade have its ids
// e.g. the spinner with id pressureUnit
secondaryView = rowChild; //We do not need to cast
}
}
// Now we construct the array
if (tv != null && secondaryView != null) {
// The id we just obtained is one from the ones you have already saved
// in an array called uiIds
int secondaryViewId = secondaryView.getId();
//Now, we need to find the index of this id in uiIds
for (int idx = 0; idx < uiIds.length; idx++) {
if ( uiIds[idx] == secondaryViewId ) {
//We have found a match. Then just add the text of the textview in the corresponding index of our new array
textLabels.set(idx,tv.getText().toString());
}
}
}
}
// At this point, textLabels should contain the text of the text view on every row
// such that the ith element in the array you already have corresponds to
// ith element of the array we just created.
// In other words, if uiIds[0] is equals to R.id.pressureUnit, then,
// textLabels.get(0) is equals to R.string.label_unit
I have edited the answer directly on the text editor so it might have some sintax erros. Hopefully this solves your problem or at least gives you an idea.

To get overview of your label mappings, I suggest to code more systematically, in this case to name the label just like the id.
#+id/pressure => #string/label_pressure
#+id/pressureUnit => #string/label_pressureUnit
I know this is not a direct answer to your question. However I think, if you work in this way, you don't need a central table of your mappings at all and your layouts become more readable. Android Studio makes it really easy to do this kind of changes.

strange jsoup behavior when getting first element

i'm new in using jsoup, so i don't know why follows appears:
...
Document doc = Jsoup.connect("http://4pda.ru").get();
Elements articleElems = doc.select("article.post");
for(Element article:articleElems)
{
Element desc = article.select("div.description").first();
Elements posts = desc.select("h1.list-post-title");
Log.d(TAG,"size is "+posts.size()); // it's ok, size is 1
...
}
so, as size is 1 i wanna to get first Element, i change the code as follows:
for(Element article:articleElems)
{
Element desc = article.select("div.description").first();
Element post = desc.select("h1.list-post-title").first();
Log.d(TAG,"post is "+post.toString()); // there NullPointerException throws
...
}
i cannot understand this...

You are selecting article that don't have h1.list-post-title
You can use has(). Here is the official doc about has()
:has(seletor): find elements that contain elements matching the selector
Here is the solution with has
Document doc = Jsoup.connect("http://4pda.ru").get();
Elements articleElems = doc.select("article.post:has(h1.list-post-title)");
for (Element article : articleElems) {
Element desc = article.select("div.description").first();
Element post = desc.select("h1.list-post-title").first();
System.out.println(post);
}

How to get text out of TextView or ListView Android?

I have a ListView. This ListView load this text/data from a URL/HTML code on a webpage. I use a for loop for it like:
for (int i = 0; i < 5; j++) {
// Search and load text in the ListView..
}
But sometimes the webpage has 5 "textfields" but maybe a new post got 8..
So, I don't want to use the 5 in the for loop anymore.. I want a for loop which is loading and loading untill he find a specific line in the html code of the webpage.
For example:
if (MaxLoad != "<p>End of the textfields</p>") {
// Search and load text in the ListView,
// untill the found text is the text between the "".
}
}
else{
Log.e("Max textfields are found!")
}
Sometimes he need to stop after 3 textfields.. But another time he need to stop after 16 textfields..
I hope I was clear enough.
Thanks,
P.S. All my code is working at the moment.. When I use the for loop system, count the textfields in the HTML manually.. Put that value into the for loop, then the code load all the textfields.. But I want it automaticly..

Use the break; statement to break out of your for loop. You can initiate the for loop with a big number like 5000.
for (int i = 0; i < 5000; j++) {
// Search and load text in the ListView..
String ItemText = .......
if ( ItemText.equals ( "blablabla" ) )
break;
}
This could be done more elegant though...

EditText is gone but values remain in memory

I have a couple of EditTexts arranged on rows and columns.Those EditTexts contain product name,quantity and price and a TextView that shows the total in real time(calculates it each time you write on one of the EditTexts)
I've setup a a button on each row that when clicked sets visibility of the row(3EditTexts for product name,price and quantity) to GONE.
My problem is that after i set the visibility to GONE,though there are no more EditTexts it still calculates their values from before being GONE.
My question now is,what happens when the EditTexts are set to visibility.GONE ?
My app calculates in real time,so when something happens to an EditText,he calculates again..but it's like the values are still there...Isn't this supposed to be the difference between invisible and gone ?
I'll show you the way i calculate(it is called even after you press the X button to erase the EditTexts,not only when you change values inside EditTexts)
public void calculeaza() {
totaltest = 0;
prod = new String[allprod.size()];
pret = new String[allpret.size()];
cant = new String[allcant.size()];
for (int m = 0; m < allprod.size(); m++) {
prod[m] = allprod.get(m).getText().toString();
if (prod[m].matches("")) {
prod[m] = " - ";
}
}
for (int j = 0; j < allcant.size(); j++) {
cant[j] = allcant.get(j).getText().toString();
if (cant[j].matches("")) {
cant[j] = Float.toString(0);
}
}
for (int k = 0; k < allpret.size(); k++) {
pret[k] = allpret.get(k).getText().toString();
if (pret[k].matches("")) {
pret[k] = Float.toString(0);
}
}
for (int l = 0; l < allpret.size(); l++) {
Float temp = Float.parseFloat(cant[l]) * Float.parseFloat(pret[l]);
totaltest = totaltest + temp;
TextView totalf = (TextView) findViewById(R.id.total);
totalf.setText(String.format("Total: %.2f", totaltest));
}
}

Lines Straight from Android dev site..
View.GONE This view is invisible, and it doesn't take any space for layout purposes.
View.INVISIBLE This view is invisible, but it still takes up space for layout purposes.
i.e it retains EditText object even after Gone..
You can reinitialise edittext if you dont want it to retain its value...or setText = ""
Above quoted is the only difference...
Hope this helps...

I'm not really seeing in the code you posted anything I can use to answer this question, but there does appear to be some confusion as to what setVisibility does:
INVISIBLE elements are not seen on the page, but they still take up space (there's a hole where they would be)
GONE elements have no visible effect on the screen, from the user's perspective they aren't there. However they are still part of the view.
If you want to remove the object from the view, then you need to call removeView() on its parent.
It may still take up memory after it has been removed from the view, in case your code has kept references to it in any variables.
It may still take up memory after there are no further references to it, at least until the garbage collector gets around to it.
I'm hoping the rather generalized statements above help clarify the situation.

Dynamically changing TextViews with a for loop

I am trying to change the values of several TextView elements but iterating through an array list and adding these values. However I can't seem to find a way to change the R.id value that is used each time. For example:
for (int i=0; i<arrayList.size(); i++)
{
TextView t = (TextView) dialog.findViewById(R.id.value+(i));
t.setText(arrayList.get(i));
}
Where the values are in the format animals_eng1,animals_eng2 etc..
Any help appreciated.

Your best bet is to create an array containing the resource IDs of each text view and looping through them..
ex.
int[] textViewIds = new int[] { R.id.animals_eng1, R.id.animals_eng2, R.id.animals_eng3 };
Then in your activity you can loop through them and set the values like you desire
for (int i=0; i<arrayList.size(); i++)
{
((TextView)findViewById(textViewIds[i])).setText(arrayList.get(i));
}
You'll have to make sure your arrayList size is the same as the number of textview resource IDs you set or you'll end up with an out of bounds exception when looping

I don't know of a way to do exactly what you're asking, but here are two alternatives:
1.Create an array of Integers, and assign each element of the array to a different view id value
int[] ids = new int[arrayList.size()];
ids[0] = R.id.view0;
ids[1] = R.id.view1;
ids[2] = R.id.view2;
//...ids[n] = R.id.viewN; where n goes up to arrayList.size()
for (int i : ids){
((TextView)dialog.findViewById(ids[i])).setText(arrayList.get(i));
}
Note that the above method sorta defeats the point because you have to have a line for every TextView, if you want something more dynamic:
2.Tag your TextViews in your layout xml by adding android:tag="prefix0", for example, to each of your TextViews. Before the loop find the parent View of your layout, and then use the findViewWithTag method of that view within the for loop. From your code I'm guessing you're using a Dialog with a custom layout xml, so you'd first find the parent of that:
ViewGroup parent = dialog.findViewById(R.id.parent); //or whatever the name of your parent LinearLayout/RelativeLayout/whatever is
String commonPrefix = "prefix"; //or whatever you've tagged your views with
for (int i=0; i<arrayList.size(); i++){
TextView t = (TextView) parent.findViewWithTag(commonPrefix+i);
t.setText(arrayList.get(i));
}

One way to solve this would be putting your resource ids in an int array and getting the resource at index i.
TextView t = (TextView) dialog.findViewById(R.id.value+(i))
becomes
TextView t = (TextView) dialog.findViewById(resourceArray[i])

if all of your views are on the same container (and only them) , simply iterate over its children .
if not , you can add an array of ids (in res) and iterate over it .