tablelayout getchildat scroll to that child - android

I actually trying something quite straightforward, however android and java are making my life not easy. The idea is to scroll to a specified child in the table layout.
I am using a Layoutinflater to add the entries to the table layout like the following :
TableLayout tl = (TableLayout)findViewById(R.id.myTableLayout3);
LayoutInflater inflater = (LayoutInflater)getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View itemView = inflater.inflate(R.layout.element_news, null);
TextView firstname = (TextView) itemView.findViewById(R.id.tvname);
firstname.setText(FN + " " + iLN);
TextView date = (TextView) itemView.findViewById(R.id.tvdate);
date.setText(newPD);
TextView post = (TextView) itemView.findViewById(R.id.tvpost);
post.setText(c.getString(iP));
post.setFocusable(true);
tl.addView(itemView, new TableLayout.LayoutParams(LayoutParams.FILL_PARENT,LayoutParams.WRAP_CONTENT));
I tried to use the getChildAt() for the tablelayout and I do get the child, however when I use the child it returns for everything "0".
Example Code:
LinearLayout row = (LinearLayout) tl.getChildAt(1);
TextView tv = (TextView) row.getChildAt(1);
tv.requestFocus();
Log.w("news", Integer.toString(tv.getHeight()));
For the TextView Height it returns "0" eventhough it contains multiple lines and the requestfocus() does not work either.
So how can I scroll to the child in the table layout?
Thanks in advance for any help.

That code sample doesn't work because you probably use it in the onCreate method and at that time the UI isn't drawn yet so the views don't have any dimensions. If this is the case you could simply post a Runnable on one of your views to delay a bit the dimensions gathering until after the onCreate method like this:
// post the Runnable
tl.post(new Runnable() {
#Override
public void run() {
LinearLayout row = (LinearLayout) tl.getChildAt(1);
// get the top position relative to the parent
int top = tr.getTop();
// scroll to that top position the wrapping ScrollView
sv.scrollTo(0, top);
}
});
There is something strange about your code(from my point of view), if the code above doesn't work you should post more details about your layout files and use scenario.

Related

How to set position of view while using addView

I'm adding multiple Views by code into Layout. I need each new View to be above previous one(top of the parent layout).
EDIT: To be more accurate I'll describe what the app module should does. User start with clean screen and one button at the bottom of the screen. The button adds a View at the top of the screen. Next clicks should add next views above previous ones to make the newest View be on the top of a container. The app saves state and on restart user see views in the same order.
Call the following method from Button's onClick Event.
private final int LAYOUT_TOP_INDEX = 0;
private void addViewOnTop(View view){
if(layout != null && view !=null)
layout.addView(view, LAYOUT_TOP_INDEX);
}
where 'layout' is your Layout (e.g., LinearLayout) to which the View is to be added.
Would really need more information from you to give a more accurate answer, but if you're saying what i think you are then you can just add these views to a LinearLayout with orientation set to vertical.
And assuming you're iterating through a list to dynamically add views, instead of incrementing from 0, increment down from the size of the list.
for(int i = size; i >= 0; i--){
linearLayout.add(new TextView(Context));
}
View positions inside ViewGroups are defined by the LayoutParams
How does this happen? Views pass their LayoutParams to their parent ViewGroups
//100% programatic approach with simple LayoutParams
LinearLayout myLinearLayout = new LinearLayout(this);
//if the **parent** of the new linear layout is a FrameLayout
FrameLayout.LayoutParams layoutParams =
new FrameLayout.LayoutParams(
FrameLayout.LayoutParams.MATCH_PARENT, FrameLayout.LayoutParams.MATCH_PARENT);
//or if you have the XML file you don't have to worry about this
//myLinearLayout = (LinearLayout)findViewById(R.id.my_simple_linear_layout);
//you could have a LinkedList<TextView>
LinkedList<TextView> textViewList = new LinkedList<>();
//assuming the order is the correct order to be displayed
Iterator<TextView> descendingIterator = textViewList.descendingIterator();
while(descendingIterator.hasNext())
{
//just add each TextView programatically to the ViewGroup
TextView tView = descendingIterator.next();
myLinearLayout.addView(tView);
}
Just like we defined LayoutParams for the LinearLayout we could also define LayoutParams for the TextView
IMPORTANT: when setting LayoutParams you need to be sure they fit the VIEWGROUP, that is the parent of the View being added
private TextView textViewFactory(String myText) {
TextView tView = new TextView(getBaseContext());
//controling the position relatively to the PARENT
//because you are adding the textview to a LINEAR LAYOUT
LinearLayout.LayoutParams paramsExample =
new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT,
LinearLayout.LayoutParams.WRAP_CONTENT, 1.0f);
tView.setLayoutParams(paramsExample);
//configuring the insides of the textview
//you can also do all kinds of stuff programatically
tView.setGravity(Gravity.CENTER_HORIZONTAL);
tView.setPadding(10, 10, 10, 10);
tView.setTypeface(Typeface.DEFAULT_BOLD);// (null, Typeface.BOLD_ITALIC);
tView.setTypeface(Typeface.SANS_SERIF);
tView.setTypeface(null, Typeface.ITALIC);
tView.setTypeface(Typeface.defaultFromStyle(R.style.AppTheme));
tView.setId(R.id.aux_info);
tView.setText(myText);
//.........all kinds of stuff really
return tView;
}
If you mean adding a view programmatically so that the new one is added above the previous one, instead of below it, then I suggest this:
Maintain an ArrayList with the items you want to turn into views
Put them into a ListView
When you want to add a new view that must appear at the top of the list, insert it as the first element of your ArrayList and recreate the ListView from it.

addview in list not displaying multiple records in android

Here i have to display list like display in right but i need like left one
For that i have created custom listview and used addview() for adding policydate,paymentdate and policyamt.
Here in my getview() method i have used this code
for(int x=0;x<noofpolicy;x++){
Log.i("Policy No",i.getpolicyno(x));
Log.i("Payment Date",i.getpaymentdate(x));
Log.i("Policy Amount",i.getpolicyamount(x)+"");
LayoutInflater inflaterforpolicylist = (LayoutInflater) getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View hiddenInfo = inflaterforpolicylist.inflate(R.layout.rowdetaillist, null);
TextView policynoView = (TextView) hiddenInfo.findViewById(R.id.policynooflist);
TextView paymentdateView = (TextView) hiddenInfo.findViewById(R.id.paymentdateoflist);
TextView policynameView = (TextView) hiddenInfo.findViewById(R.id.policyamtoflist);
policynoView.setText(i.getpolicyno(x));
paymentdateView.setText(i.getpaymentdate(x));
policynameView.setText(i.getpolicyamount(x)+"");
myLayout.addView(hiddenInfo, x, new ViewGroup.LayoutParams(ViewGroup.LayoutParams.FILL_PARENT, ViewGroup.LayoutParams.FILL_PARENT));
}
it showing all the record in logcat.
So here my question is that why it showing blank space in result and not displaying multiple records? What change i have to do in my code for displaying multiple records?
Use ViewGroup.LayoutParams.WRAP_CONTENT so that data which is not appearing to you that you can see and after that change in your xml by that it occupies full width for each record.

Element overlap in GridView

Is it possible to make one element overlap others in GridView as it is shown on screenshot here: https://bigbob.lv/elem.png? I mean blue element.
I would like to distinguish current level this way.
I have tried bringToFront(); method in getView(); method of my custom ArrayAdapter but it doesn't work. I tried it this way:
if(i == parentActivity.currentLevel) {
RelativeLayout parentLL = (RelativeLayout) gridView.findViewById(R.id.levelLL);
ViewGroup.LayoutParams rp = (ViewGroup.LayoutParams) parentLL.getLayoutParams();
rp.width = parentActivity.getRelativeWidth(20f);
parentLL.bringToFront();
parentLL.requestLayout();
}
Thanks!

Adding views dynamically in a for loop results in haphazard positioning - Android

I am adding views dynamically to a relative layout (let's say container) in a for loop. There is some thing strange I am noticing. When adding rows one below the other in a relative layout in a for loop, I see that the first time a few of the views are overlapping. But when I lock and unlock the screen, I can see that the views are placed correctly.
Should I be aware of something when adding views dynamically to a relative layout?
Edit
I have found a solution as to how to get rid of this (please check my answer). But I would be more than glad to accept an answer that analyses this problem and tells me why this happens.
I have simplified to code and the comments should give a good idea as to what I am doing.
int prev_id=ID_OF_THE_ELEMENT_ABOVE;
/*Empty RelativeView with width and height as MATCH_PARENT and WRAP_CONTENT respectively*/
RelativeLayout container=(RelativeLayout) findViewById(R.id.container);
while(ThereIsData){
/*GET THE DATA HERE THAT HAS TO BE ASSIGNED TO EACH TEXTVIEW*/
...
/* ADD TEXTVIEW #1 below prev_id/
...
...
/*ADD TEXTVIEW #2 (WITH BASELINE OF TEXTVIEW#
...
...
/*TEXTVIEW #3 (BELOW TEXTVIEW#1)*/
...
...
/*TEXTVIEW #4 (BELOW TEXTVIEW#2)*/
...
...
/*ASSIGN THE ID OF TEXTVIEW#3 TO prev_id SO THAT
IN THE NEXT ITERATION TEXTVIEW#1 CAN USE prev_id
*/
prev_id=ID(TEXTVIEW#2);
/*ADD TEXTVIEWS CREATED IN THIS ITERATION*/
container.addView(TEXTVIEW#1);
container.addView(TEXTVIEW#2);
container.addView(TEXTVIEW#3);
container.addView(TEXTVIEW#4);
}
It is due to the fact that you are having a RelativeLayout with height as WRAP_CONTENT, and adding a view doesn't refresh the whole container at that time.. so as you answered you can add a line to measure the dimensions explicitly or invalidate the view to recreate it completely.
In any case LinearLayout would be better to opt-for as it will automatically arrange the children in horizontal or vertical manner and you can even add the new view in any place other than last position and it will automatically be updated..
I used to struggle against common issues a year ago, when I was working on a library for dynamically creating layouts from XML files (as Android does not support this). So when you dynamically add views to a RelativeLayout you have to take in mind a few things:
Create the container View (in this case the RelativeLayout)
Create all views without assigning any layout parameters.
Add all child views to the container.
Iterate over the container's children and populate each child's layout parameters. This is needed because when the relational constraints are applied an Excpetion is thrown if the relative View is missing (was not previously added to the container).
This is an example code taken from the project I used to work on. Take in mind that it is just a single part so it contains references to classes that are not defined in the Android API. I am sure it will give you the basic idea of dynamically creating RelativeLayot:
private void setChildren(RelativeLayout layout, T widget,
InflaterContext inflaterContext, Context context,
Factory<Widget, View> factory) {
List<Widget> children = widget.getChildren();
if (Utils.isEmpty(children))) {
return;
}
// 1. create all children
for (Widget child : children) {
View view = factory.create(inflaterContext, context, child);
layout.addView(view);
}
// 2. Set layout parameters. This is done all children are created
// because there are relations between children.
for (Widget child : children) {
try {
View view = ViewIdManager.getInstance().findViewByName(layout, child.getId());
if (view != null) {
populateLayoutParmas(child, view);
}
} catch (IndexNotFoundException e) {
Log.e(LOG_TAG, "Cannot find a related view for " + child.getId(), e);
}
}
}
I have not yet found the answer to why this is happening. But I have found a solution. After adding each row in the loop, call container.measure(RelativeLayout.LayoutParams.WRAP_CONTENT,RelativeLayout.LayoutParams.WRAP_CONTENT);
This seems to solve the problem. But I really think that container.addView() should also be calling measure().
/*ADD TEXTVIEWS CREATED IN THIS ITERATION*/
container.addView(TEXTVIEW#1);
container.addView(TEXTVIEW#2);
container.addView(TEXTVIEW#3);
container.addView(TEXTVIEW#4);
//---------------------------------------------------------------------
container.measure(RelativeLayout.LayoutParams.WRAP_CONTENT,RelativeLayout.LayoutParams.WRAP_CONTENT);
//Declare globally
LinearLayout[] layout;
ImageView[] imageView1;
ImageView[] imageView2;
ImageView[] imageView3;
// Initialize your layout. It would be RelativeLayout too. Just reference to it.
LinearLayout ll = (LinearLayout) findViewById(R.id.mylinear);
// set listview row size as your demand
layout = new LinearLayout[200];
imageView1 = new ImageView[200];
imageView2 = new ImageView[200];
imageView3 = new ImageView[200];
for (int i = 0; i < 200; i++) {
layout[i] = new LinearLayout(this);
layout[i].setBackgroundResource(R.drawable.book_shelf);
// layout[i].setLayoutParams(new
// LinearLayout.LayoutParams(android.widget.LinearLayout.LayoutParams.FILL_PARENT,
// 120));
layout[i].setLayoutParams(new LinearLayout.LayoutParams(
android.widget.LinearLayout.LayoutParams.FILL_PARENT, 220));
imageView1[i] = new ImageView(this);
imageView2[i] = new ImageView(this);
imageView3[i] = new ImageView(this);
imageView1[i].setLayoutParams(new LinearLayout.LayoutParams(0, 200,
0.33f));
imageView1[i].setPadding(0, 20, 0, 0);
imageView1[i].setImageResource(R.drawable.bibid_one_bankim);
imageView2[i].setLayoutParams(new LinearLayout.LayoutParams(0, 200,
0.33f));
imageView2[i].setPadding(0, 20, 0, 0);
imageView2[i].setImageResource(R.drawable.bibid_two_bankim);
imageView3[i].setLayoutParams(new LinearLayout.LayoutParams(0, 200,
0.33f));
imageView3[i].setImageResource(R.drawable.dena_pawna);
imageView3[i].setPadding(0, 20, 0, 0);
layout[i].setId(i);
layout[i].setClickable(true);
final int j = i;
layout[i].addView(imageView1[i]);
layout[i].addView(imageView2[i]);
layout[i].addView(imageView3[i]);
ll.addView(layout[i]);
}
}
Try adding your views in vertical Linear Layout.
Following link might help you
http://www.myandroidsolutions.com/2012/06/19/android-layoutinflater-turorial/
Inflate your layout in for loop.

handling LinearLayout within a ScrollView

Originally, I had LinearLayout>ScrollView>TableLayout and the code below:
LinearLayout layout = (LinearLayout) View.inflate(this, R.layout.photos_layout, null);
setContentView(layout);
// TODO Auto-generated method stub
//get the tableLayout which we created in main.xml
tl = (TableLayout)findViewById(R.id.tableLayout1);
for(int i = 0; i < names.length; i++) {
//Create a new row to be added.
TableRow tr = new TableRow(this);
//Create text views to be added to the row.
TextView tv1 = new TextView(this);
TextView tv2 = new TextView(this);
//Put the data into the text view by passing it to a user defined function createView()
createView(tr, tv1, Integer.toString(i+1));
createView(tr, tv2, names[i]);
//Add the new row to our tableLayout tl
tl.addView(tr);
}
The problem is that a scrollView can only have one child, so if I wanted to add more views in addition to the tableLayout I can't. In order to overcome this problem I made the hierarchy like LinearLayout>ScrollView>linearLayout>tableLayout. However, now the code above crashes the app.
What do I need to change in order to populate my table, as well as add views to my newly created linearlayout?
I'd suggest removing the parent LinearLayout. Scrollview in itself can be the parent, and then have one LinearLayout as its only direct child.
In the code you posted that you mentioned was crashing, you're not adding any view to your "newly-created" LinearLayout, instead you're adding a new row to your TableLayout, which if I guess correctly, is inside your scrollview. This is perfectly ok and should not be the cause of the crash.

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