Develop Reference

Buttons not displaying from FOR loop

I have been attempting to programmatically add buttons based on a list of values.
PROBLEM: Only one button is produced, rather than a series. This button contains the information of the last value in the array.
I gather an array of values aptly named 'values', I then use a for loop to add the buttons.
Here is the code of my loop to add buttons:
public void updateButtons(List<String> values, View rootView) {
//Find relative layout
RelativeLayout rl = (RelativeLayout) rootView.findViewById(R.id.RelativeLayoutManage);
RelativeLayout.LayoutParams params = new RelativeLayout.LayoutParams(
RelativeLayout.LayoutParams.WRAP_CONTENT,
RelativeLayout.LayoutParams.WRAP_CONTENT);
params.setMargins(50, 10, 50, 10);
for (String mTrip : values) {
//New button
Button Postbtn = new Button(mContext);
//Style
Postbtn.setBackgroundResource(R.drawable.buttonshape);
Postbtn.setTextColor(getResources().getColor(R.color.DarkGreen));
Postbtn.setTextSize(25);
//set text
Postbtn.setText(mTrip.toString());
//set id
Postbtn.setId(i);
int id_ = Postbtn.getId();
//Add to view
rl.addView(Postbtn, params);
Postbtn = ((Button) rootView.findViewById(id_));
//Add listener
Postbtn.setOnClickListener(new OnClickListener() {
public void onClick(View view) {
Log.v("TripNumber", Integer.toString(i));
//TODO: Change Fragment
}
});
i++;
}
}
And my corresponding layout file if needed:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout android:id="#+id/RelativeLayoutManage"
android:layout_height="fill_parent"
android:layout_width="fill_parent"
xmlns:android="http://schemas.android.com/apk/res/android">
</RelativeLayout>

Seems that they might be overlapping each other. You need to use a LinearLayout
<LinearLayout android:id="#+id/RelativeLayoutManage"
android:layout_height="fill_parent"
android:layout_width="fill_parent"
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="horizontal"
/>

You are adding Button to RelativeLayout. In your current code all your buttons are present but one above other. You should make one below/above other to make all buttons visible. Else use a LinearLayout

I solved the problem by positioning each button as it is added to the layout. Simply using:
params.addRule(RelativeLayout.BELOW, Postbtn.getId() - 1);
Postbtn.setLayoutParams(params);

Nesting layouts and dynamically updating them

I want to nest a TableLayout inside a RelativeLayout and later dynamically edit the TableLayout in my Java Code.
My XML-File looks like this:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/activity_load_date"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".LoadDateActivity" >
<!-- few buttons and textviews -->
<TableLayout
android:id="#+id/activity_load_date_table_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_below="#+id/button" >
</TableLayout>
</RelativeLayout>
Java Code:
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_load_date);
//Do something with my Buttons and TextViews(this works fine)
tblLayout = (TableLayout) findViewById(R.id.activity_load_date_table_layout);
}
#Override
public void onClick(View v) {
if (v.getId() == R.id.button_calc) {
for (int i = 0; i < listOfEntries.size(); i++) {
Entry temp = listOfEntries.get(i);
if (temp.getDate().getTime() >= startDate.getTime()
&& temp.getDate().getTime() <= endDate.getTime()) {
TableRow tr = new TableRow(this);
TextView comm = new TextView(this);
comm.setText(listOfEntries.get(i).getComment());
TextView val = new TextView(this);
val.setText(String.valueOf(listOfEntries.get(i).getValue()));
LayoutParams params = new LayoutParams(0,
LayoutParams.WRAP_CONTENT, 1f);
tr.setLayoutParams(params);
tr.addView(comm);
tr.addView(val);
tblLayout.addView(tr);
}
}
tblLayout.invalidate(); //Shouldn't this redraw the entire TableLayout and therefore adding my TableRows? This is not working.
}
}
Through various tests with TextViews and Toasts I have gathered that the tblLayout should be filled and the TableRows are added to the Layout, the only thing that is not working is the "repainting" of my Layout. How do I achieve that?
Edit:
Apparently the thing that made this not work was actually the LayoutParams given to the TableRow, once I commented those out I atleast got it printed to the screen. They are however not where I expect them to be.
I expected them to be below the buttons, instead they are in the top left corner on top of the buttons. This leads me to believe that the TableLayout is actually the same size as the RelativeLayout but is layered above the RelativeLayout. The error should therefor lie in my XML-File. What height do I need to give my TableLayout to make this work the way I expect?
Edit2:
I needed to add the android:layout_below attribute to my TableLayout, works as a charm now!

You need to call the method "requestLayout()"
Call this when something has changed which has invalidated the layout of this view. This will schedule a layout pass of the view tree.

button is squeezed when it exceeds layout

In my code, I create buttons dinamically. When I create multiple buttons is the following problem:
How do I get it when it happens the button is put down?
My code:
private void showGlossary(String ContentTab) {
LinearLayout layout;
LinearLayout.LayoutParams p;
layout = (LinearLayout) findViewById(R.id.GlossaryTab1);
p = new LinearLayout.LayoutParams(
LinearLayout.LayoutParams.WRAP_CONTENT,
LinearLayout.LayoutParams.FILL_PARENT
);
Glossary = (TextView) findViewById(R.id.glossary);
Glossary.setText("Glossário:");
while (ContentTab.indexOf("<gloss") != -1) {
ContentTab = ContentTab.substring(ContentTab.indexOf("<gloss"));
uri = ContentTab.substring(ContentTab.indexOf("<gloss") + 1, ContentTab.indexOf(">"));
Button myButton = new Button(this);
myButton.setText(Html.fromHtml(ContentTab.substring(ContentTab.indexOf(">") + 1, ContentTab.indexOf("</gloss>"))));
myButton.setLayoutParams(p);
myButton.setContentDescription(uri);
layout.addView(myButton);
myButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view)
{
Toast.makeText(ShowPhytoterapicActivity.this, Html.fromHtml(getGlossaryItem(view.getContentDescription().toString())), Toast.LENGTH_LONG).show();
}
});
if(ContentTab.indexOf("</gloss>") != -1)
ContentTab = ContentTab.substring(ContentTab.indexOf("</gloss>") + 9);
}
}
My XML:
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="fill_parent"
android:id="#+id/GlossaryTab1"
android:orientation="horizontal"
>
</LinearLayout>
Can anyone help me? Thanks!

You could set all of your buttons' weights to 1, but that would cause all of your buttons to become "Squished".
Do you think a HorizontalScrollField would work? I think that may be the best solution.
Just wrap your LinearLayout in a HorizontalScrollField and add your buttons to the LinearLayout as you are now.

Fitting 3 buttons in one row seems a bit messy. You could try a different layout style, perhaps a triangular setup, or change your UI design into something more compact and change the flow of how the buttons appear.

I made a LinearLayout Vertical same, thanks to everyone for the answers. :)

adding views dynamically

I am using the following layout and want to add textviews one below another dynamically(depending on the data I want to display)
main.xml
<?xml version="1.0" encoding="utf-8"?>
<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<LinearLayout
android:id="#+id/contain"
android:layout_width="match_parent"
android:layout_height="wrap_content" >
</LinearLayout>
</ScrollView>
So I tried this
public class Feeds extends Activity {
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
Intent intent=getIntent();
Bundle b=intent.getExtras();
String s= b.getString("datapack");
Log.w("String",s);
String data[]=s.split("#");
String temp="";
LinearLayout l=(LinearLayout)findViewById(R.id.contain);
LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(
(LayoutParams.WRAP_CONTENT), (LayoutParams.WRAP_CONTENT));
RelativeLayout relative = new RelativeLayout(getApplicationContext());
relative.setLayoutParams(lp);
for(int i=1;i<data.length;i++)
{Log.w("i data",data[i]);
temp=temp + data[i] + ",";
Log.w("tag",temp);
if(i%5==0)
{Log.w("data",temp);
TextView tv = new TextView(getApplicationContext());
tv.setLayoutParams(lp);
tv.setId(i);
tv.setText(temp);
relative.addView(tv, lp);
temp=null;
}
}
l.addView(relative);
}
}
I am using Scrollview for the first time so that is crating a bit of problem but the main problem is that the textviews in the relative layout overlap one another.How can I specify the gap between each view??

If you're adding views into a RelativeLayout you have to set where the view will be placed, different than LinearLayout that you only need to add the views inside there.
Trye to change to this
LinearLayout layout= new LinearLayout (getApplicationContext());
layout.setLayoutParams(lp);
And here you go a little tip. Do not do this
if(i%5==0)
{Log.w("data",temp);
try to do this
if(i%5==0){
Log.w("data",temp);
it's better to read and understand

I don't see where you are defining the positions for each textview, ie layout_below, layout_toLeftOf... If no positions are defined the relative layout stacks each view in the upper left corner.
Addition
It seems digulino and I agree. I would like to add that you should be able to get the layout scheme you want with only a RelativeLayout inside a ScrollView, maybe a HorizontalScrollView too if you want horizontal scrolling with fling gesture support.

Dynamically adding content to RelativeLayout

Since I'm still just learning Android (and it appears Amazon says it'll be 2 months till I get the Hello, Android book) I'm still playing around with doing simple things. I have no problem getting an icon to display with the click of a button on my RelativeLayout using ImageView. The code for creating it is as follows:
private int mIconIdCounter = 1;
private ImageView addIcon(){
ImageView item = new ImageView(this);
item.setImageResource( R.drawable.tiles );
item.setAdjustViewBounds(true);
RelativeLayout.LayoutParams params = new RelativeLayout.LayoutParams( LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT );
if( mIconIdCounter != 1 ){
params.addRule(RelativeLayout.RIGHT_OF, 1 );
}
item.setLayoutParams( params );
item.setId( mIconIdCounter );
++m_IconIdCounter;
return item;
}
and the code to add the item is:
Button addButton = (Button)findViewById(R.id.add_new);
addButton.setOnClickListener( new OnClickListener(){
#Override
public void onClick(View view) {
addContentView( addIcon(), new RelativeLayout.LayoutParams( LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT ) );
}
});
When I click my button what happens is all the newly created views are placed atop one another. I'd like them to be placed to the right of the next element. I did a quick search on SO for articles relating to RelativeLayout and found some that were similar (here, here, here, and here) but while these addressed getting the content into the RelativeView they didn't seem to address the positioning aspect.
What am I doing wrong?
EDIT:
My main xml looks like:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<Button
android:id="#+id/add_new"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/add_new"
android:layout_alignParentBottom="true" />
</RelativeLayout>

It looks like you might be adding the view to the root of the layout xml instead of the RelativeLayout.
You could try:
RelativeLayout layout = (RelativeLayout)findViewById(R.id.my_layout);
layout.addView(addIcon());

you are creating new relative layout inside function call. So every time new relative layout created and it added in the view when click button . Use common relative layout.