Develop Reference

(android) an scrollview that gets programmatically filled loses title

I have this layout:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_centerInParent="true"
android:layout_centerVertical="true"
android:background="#000"
android:gravity="center_horizontal|center_vertical"
android:orientation="vertical">
<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:gravity="center_horizontal|center_vertical">
<LinearLayout
android:id="#+id/linearLayout1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:gravity="center"
android:orientation="vertical">
<TextView
android:id="#+id/title"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:contentDescription="#string/play"
android:gravity="center_horizontal"
android:scaleType="centerInside"
android:text="#string/highScores"
android:textAppearance="?android:attr/textAppearanceMedium"
android:textColor="#fff" />
<View
android:layout_width="1dp"
android:layout_height="20dp"></View>
<TableLayout
android:id="#+id/container"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:gravity="center_vertical|center_horizontal">
</TableLayout>
</LinearLayout>
</ScrollView>
</LinearLayout>
I fill the 'container' TableLayout with elements like this:
layout.addView(buildTitleRow());
for (int i = 0; i < users.length(); i++) {
JSONObject parent = (JSONObject) users.get(i);
layout.addView(buildRowFrom(parent, i + 1));
}
buildTitleRow:
private TableRow buildTitleRow(){
TableRow result = new TableRow(this);
int color = Color.parseColor("#ffff00");
View view = new View(this);
view.setMinimumWidth(10);
result.addView(view);
view = new View(this);
view.setMinimumWidth(10);
result.addView(view);
//the same for other views
return result;
}
buildRowFrom:
private TableRow buildRowFrom(final JSONObject element, int counter) throws JSONException {
TableRow result = new TableRow(this);
String rowName = element.getString("name");
int color = Color.parseColor("#00ff00");
if(rowName.equals(userName)){
color = Color.parseColor("#ffffff");
}
TextView textView = new TextView(this);
textView.setText(counter + ".");
textView.setTextColor(color);
result.addView(textView);
//some other views
return result;
}
this really works well just until the scrolling needs to take place...
Once there are more elements than the height of the screen the table remains scrollable (luckily) but the original 'title' Textview doesn't show up anymore (you can't scroll up towards it anymore)
Does anyone know how to tweak the layout to keep it visible once more elements are added than the size of the screen?
Thanks a lot,
S.

I've tried your code and found find something wrong in your xml layout.
The attribute android:layout_gravity will change the layout's own gravity. So if set this attribute to a LinearLayout with center and its android:layout_height is wrap_content(means that the real height of the 'LinearLayout' will exceed the screen's height) and fill ScrollView(its height is the screen's height) with it, the LinearLayout will align to center of its parent ScrollView.
If you want to keep the content of 'LinearLayout' centered, you can set android:fillViewport="true" to ScrollView and then the LinearLayout will fill the parent and you can use android:gravity="center" on the LinearLayout. Reference
But there is still some thing need to be changed. In your java code, View view = new View(this) this line will new a View and then you add it into TableLayout. But this TableLayout will be full of View because of the description of View below.
* The base class implementation of measure defaults to the background size,
* unless a larger size is allowed by the MeasureSpec. Subclasses should
* override {#link #onMeasure(int, int)} to provide better measurements of
* their content.
You can use a concrete view like TextView instead of it.
I don't know if I have clarified it. I think if you remove the attribute android:layout_gravity of LinearLayout, it will work.
I'm glad if it would help.

I did the adaptations Paul suggested + change android:layout_height of the ScrollView to "wrap_content" to keep the inner LinearLayout centered when the android:layout_gravity="center" was removed from it (see complete layout below).
I wouldn't have found it without Paul's suggestion and explanation so I'll accept his answer as answer, this answer is just for the sake of completeness...
I'm not expecting this question to get that much of attention anyways ;-)
Thanks Paul :-D
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_centerInParent="true"
android:layout_centerVertical="true"
android:background="#000"
android:gravity="center_horizontal|center_vertical"
android:orientation="vertical">
<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:gravity="center_horizontal|center_vertical">
<LinearLayout
android:id="#+id/linearLayout1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="center"
android:orientation="vertical">
<TextView
android:id="#+id/title"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:contentDescription="#string/play"
android:gravity="center_horizontal"
android:scaleType="centerInside"
android:text="#string/highScores"
android:textAppearance="?android:attr/textAppearanceMedium"
android:textColor="#fff" />
<View
android:layout_width="1dp"
android:layout_height="20dp"></View>
<TableLayout
android:id="#+id/container"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:gravity="center_vertical|center_horizontal">
</TableLayout>
</LinearLayout>
</ScrollView>
</LinearLayout>

Weighted View in Layout

I try to add a PlotView (custom View) into a LinearLayout. My LinearLayout has a weightSum of 8. Inside my .xml I defined a Space (weight of 3) that has to appear above my PlotView and a Button (weight of 1) that should follow my plot underneath. So far, so good.
Now the PlotView is added programmatically, with a weight of 4. However, it will always consume almost the entire screen, and I am not sure what I am doing wrong here.
My Code:
main_activity.xml (snippet)
<LinearLayout
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="fill_parent"
android:layout_alignParentEnd="true"
android:id="#+id/linlayout"
android:weightSum="8">
<Space
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal"
android:layout_weight="3"/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/calibrate"
android:id="#+id/calibration"
android:layout_weight="1"
android:layout_gravity="center_horizontal" />
</LinearLayout>
main_activity.java (snippet)
LinearLayout layout = (LinearLayout) findViewById(R.id.linlayout);
plotView.setLayoutParams(new LinearLayout.LayoutParams(
LinearLayout.LayoutParams.MATCH_PARENT,
LinearLayout.LayoutParams.WRAP_CONTENT, 4f));
layout.addView(plotView, 1);
Any idea what I am doing wrong?

The solution is to set the height, which is affected by the weight, to 0.
Code in .xml:
android:layout_height="0dp"
Code in .java:
plotView.setLayoutParams(new LinearLayout.LayoutParams(
LinearLayout.LayoutParams.MATCH_PARENT, 0, 4f));

Why is setMargins not working with my RelativeLayout?

I have a RelativeLayout inside of another Relative Layout.When i use the inner layout to be LinearLayout the code works fine however.I read about many such questions here on SO.Sometimes it was mentioned that the layout params used should be of the parent layout. I wasnt able to quite understand it.Is this where I am going wrong?
Thanks in advance guys !
MY XML FILE
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:id="#+id/rel1" >
<RelativeLayout
android:id="#+id/ll"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_alignParentBottom="true"
android:layout_alignParentLeft="true"
android:layout_alignParentRight="true"
android:layout_alignParentTop="true" >
<ImageView
android:id="#+id/imageView1"
android:layout_width="120dp"
android:layout_height="60dp"
android:layout_alignParentRight="true"
android:layout_centerVertical="true"
android:layout_marginRight="20dp"
android:src="#drawable/helo" />
</RelativeLayout>
</RelativeLayout>
Function Where I use margins
public void showcopter()
{
ImageView image=(ImageView)findViewById(R.id.imageView1);
RelativeLayout.LayoutParams lp=(RelativeLayout.LayoutParams)(image.getLayoutParams());
lp.leftMargin =0;//(int)((width-150)*density);
lp.topMargin=(int)(hg-(30*density)); //hg is a global variale which stores the screen height
// Log.d("hello_girl",hg+" ");
// lp.setMargins((int) ((width-150)*density),(int)(hg-(30*density)),0,0);
image.setLayoutParams(lp);
image.requestLayout();
}

Since you have set android:layout_alignParentRight to be true, leftMargin won't take effect, and while you set android:layout_centerVertical to be true, topMargin won't take effect either.

how to avoid overlapping of dynamically positioned views

how to avoid overlapping of dynamically positioned views?
I have a RelativeLayout , and i am adding views dynamically(at runtime) at particular position(x,y coordinates) but the problem is the views are overlapping.
How to avoid this.
Thanks in advance.
<ScrollView
android:layout_width="fill_parent"
android:layout_height="wrap_content" >
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="vertical" >
<RelativeLayout
android:id="#+id/rl_main"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="vertical" >
</RelativeLayout>
<LinearLayout
android:layout_width="fill_parent"
android:id="#+id/ll_mainBottom"
android:layout_height="wrap_content"
android:orientation="vertical" >
</LinearLayout>
</LinearLayout>
</ScrollView>
javacode
ll_main = (RelativeLayout) findViewById(R.id.rl_main);
if (views[3].equals("textView")) {
TextView tv_new = new TextView(TenMinActivity.this);
// location
int x = Integer.parseInt(views[12]);
int y = Integer.parseInt(views[13]);
String bgColor = "#" + views[4];
String fgColor = "#" + Views[5];
tv_new.setBackgroundColor(Color.parseColor(bgColor)); // Bg Color
tv_new.setTextColor(Color.parseColor(fgColor)); // Text color
RelativeLayout.LayoutParams params = new RelativeLayout.LayoutParams(
width, android.view.ViewGroup.LayoutParams.WRAP_CONTENT);
params.leftMargin = x;
params.topMargin = y;
ll_main.addView(tv_new, params);
}else if(views[3].equals("edittext")){
....
}

Give
android:paddingLeft=""
and to each element so that the ones to the left most of the screen will have bit of space. and the ones to the right,give
android:paddingBottom=""
First,check the first 2 elements that is the name text and your text field after that you can proceed to the rest.
I can guide you better,if you post your code
Check this,
<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"
tools:context=".MainActivity" >
<TextView
android:id="#+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:padding="5dp"
android:text="Name"
android:textSize="18sp" />
<EditText
android:id="#+id/editText1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignBottom="#+id/textView1"
android:layout_alignParentTop="true"
android:layout_marginLeft="21dp"
android:layout_toRightOf="#+id/textView1"
android:ems="10"
android:padding="10dp"
android:paddingl="10dp" >
<requestFocus />
</EditText>
</RelativeLayout>

You need to learn how layouts work, first try to make the same layout in xml. Then you will learn that this kind of layout can easily be made using LinearLayout.
You can use parent LinearLayout and add sublayouts to it. Now you say if you use LinearLayout all subviews are shown vertically. It shows vertically because you are adding them one by one. If you take a RelativeLayout and add your TextView and EditText to it and then add that RelativeLayout to your LinearLayout, you will get the desired result.
<LinearLayout>
<RelativeLayout>
<TextView />
<EditText />//use layout_margin or layout_toLeftOf for moving to to right
</RelativeLayout>
<RelativeLayout>
<TextView/>
<EditText/>
</RelativeLayout>
</LinearLayout>

Please use Layout params like layout_below layout_above toRightof and ToLeftof when you add a view to container relative layout
https://stackoverflow.com/a/5191159/1911784

you an use below code to add views in your layout
RelativeLayout.LayoutParams newParams = new RelativeLayout.LayoutParams(
RelativeLayout.LayoutParams.WRAP_CONTENT,
RelativeLayout.LayoutParams.WRAP_CONTENT);
TextView text2 = new TextView(context);
newParams.addRule(RelativeLayout.ALIGN_PARENT_RIGHT);
newParams.addRule(RelativeLayout.ALIGN_PARENT_TOP);
newParams.addRule(RelativeLayout.ALIGN_BOTTOM, text1.getId());
text2.setLayoutParams(newParams);
layout.addView(text2);
where layout is your main layout.
you can use other params as well - like rightof, leftof etc

Adding a view to a LinearLayout at a specified position

I have the following main.xml file with a LinearLayout
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:weightSum="1" android:id="#+id/llid">
<TextView android:text="Client profile"
android:id="#+id/ProfileName"
android:layout_width="fill_parent"
android:textStyle="bold"
android:layout_height="wrap_content"
android:gravity="center_horizontal">
</TextView>
<TextView android:text="Specs"
android:id="#+id/Specs"
android:layout_width="fill_parent"
android:textStyle="bold"
android:layout_height="wrap_content"
android:gravity="center_horizontal">
</TextView>
</LinearLayout>
I add an image to the LinearLayout via code at runtime like so
ImageView image = new ImageView(this);
image.setImageBitmap(bmp);
LinearLayout ll = (LinearLayout) findViewById(R.id.llid);
ll.addView(image);
However, I want to add the ImageView between the 2 TextViews in my LinearLayout. I can't seem to find a way in the android docs to add a view before another view, or after. How can I do this?
NB I call
setContentView(R.layout.main);
Before I add the ImageView to the LinearLayout.

When adding a View to a ViewGroup, you can specify an index which sets the position of the view in the parent.
You have two views and so (counting from zero) you would want to add at the 1st position; just call ll.addView(image, 1); to have it placed in between the two TextViews.

The docs state you can use the index to insert it where you want. I see you are using the signature of the view only, did you try the signature with the index parameter?
public void addView(View child, int index)

I faced a similar problem. In my case I wanted to add a LinearLayout at last position of another LinearLayout. To accomplish it, I did:
LinearLayout parentLayout = (LinearLayout) findViewById(R.id.parentLayout);
LinearLayout layout = new LinearLayout(this);
layout.setLayoutParams(new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT));
// add others views to your linear layout
parentLayout.addView(layout, parentLayout.getChildCount());

setContentView(R.layout.main);
ImageView img = (ImageView) findViewById(R.id.imagefield);
img.setImageResource(your_image_here);
and in the xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:weightSum="1"
android:id="#+id/llid">
<TextView android:text="Client profile"
android:id="#+id/ProfileName"
android:layout_width="fill_parent"
android:textStyle="bold"
android:layout_height="wrap_content"
android:gravity="center_horizontal">
</TextView>
<ImageView android:id="#+id/imagefield"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
</ImageView>
<TextView android:text="Specs"
android:id="#+id/Specs"
android:layout_width="fill_parent"
android:textStyle="bold"
android:layout_height="wrap_content"
android:gravity="center_horizontal">
</TextView>
</LinearLayout>

Add an ImageView into the xml, and if its not being used, make it invisible (image.setVisibility(View.INVISIBLE)). It may not show anything anyway when no image is set.

To get position of view in a view group
val targetPosition = oldLL.indexOfChild(viewToAdd)
To add a view at a position in a view group
newLL.addView(viewToAdd,targetPosition)