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Android - Trying to make Dialog with ImageView code

What I'm trying to do is when an Imageview item being preesed, then a Dialog will open up and show the inage in a large scale.
Now first of all this is the XML layout of the dialog -
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<ImageView
android:id="#+id/imageView_large_pic"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/bkgnd_pressed" />
</LinearLayout>
Now the code to the Dialog is as follows -
Dialog settingsDialog = new Dialog(MainChat.this);
settingsDialog.getWindow().requestFeature(Window.FEATURE_NO_TITLE);
settingsDialog.setContentView(getLayoutInflater().inflate(R.layout.image_large
, null));
ImageView ivLarge = (ImageView) findViewById(R.id.imageView_large_pic);
String pathpic = v.getTag().toString();
ivLarge.setImageURI(Uri.parse(pathpic));
settingsDialog.show();
Now I tried to dubuging this code, and it get stuck at this line - ivLarge.setImageURI(Uri.parse(pathpic));
The logcat gives me that this is java.lang.NullPointerException error.
Thanks for any kind of help

You are looking in the wrong place for the ImageView
ImageView ivLarge = (ImageView) findViewById(R.id.imageView_large_pic);
is looking in the layout you inflate in setContentView(). Instead, you need to look in the Dialog's layout. Try instead
ImageView ivLarge = (ImageView) settingsDialog .findViewById(R.id.imageView_large_pic);

Positioning ImageView in two lines programmatically

I have a code which generate several ImageView and put it on Layout.
for (int i = 0; i < NUMBER_OF_MATCHES; i++) {
imageView = new ImageView(this);
if (random.nextBoolean()) {
imageView.setImageResource(R.drawable.match);
} else {
imageView.setImageResource(R.drawable.match_inverse);
}
gameLinearLayout.addView(imageView, 0, params);
}
But all images are in one line. I want to place it in two lines. Which layout to use and how to fix code for working correctly?

If I understand correctly, you want 2 seperate rows of images.
So we need a base LinerLayout with a vertical orientation to hold each row, while each row consists of a LinerLayout with a horizontal orientation:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/gameLayout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical" >
<LinearLayout
android:id="#+id/row1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal" />
<LinearLayout
android:id="#+id/row2"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal" />
</LinearLayout>

look here for explanation why it is happening:
Place two ImageViews programmatically
and look here for explanation to the last answer in this thread which talking about RelativeLayout Rules:
How to set RelativeLayout layout params in code not in xml

Try out as below:
//LinearLayOut Setup
LinearLayout linearLayout= new LinearLayout(this);
linearLayout.setOrientation(LinearLayout.VERTICAL);
linearLayout.setLayoutParams(new LayoutParams(
LayoutParams.MATCH_PARENT,
LayoutParams.MATCH_PARENT));
for (int i = 0; i < NUMBER_OF_MATCHES; i++)
{
//ImageView Setup
ImageView imageView = new ImageView(this);
//setting image resource
if (random.nextBoolean()) {
imageView.setImageResource(R.drawable.match);
} else {
imageView.setImageResource(R.drawable.match_inverse);
}
//setting image position
imageView.setLayoutParams(linearLayout);
//adding view to layout
linearLayout.addView(imageView);
}

Add imageview to layout

I want to create image view from code and add to layout...But l don't use in-code setup layout.I have RelativeLayout in xml and use that setContentView(R.layout.activity_game);
How add imageview to layout?

RelativeLayout rl = (RelativeLayout)findViewById(R.id.id_of_your_relative_layout_here);
ImageView iv = new ImageView(this)
iv.setImageResource(R.drawable.some_drawable_of_yours); //or iv.setImageDrawable(getResources().getDrawable(R.drawable.some_drawable_of_yours));
rl.addView(iv);

The XML should be:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:id="#+id/relativeblablabla"
android:layout_width="match_parent"
android:layout_height="match_parent">
...........YOUR CODE HERE............
</RelativeLayout>
The code (inside the onCreate):
RelativeLayout rl = (RelativeLayout)findViewById(R.id.relativeblablabla);
ImageView imageView = new ImageView (this);
iv.setImageResource(R.drawable.YOUR_IMAGE);
rl.addView(imageView);

The content of a LinearLayout isn't visible

I tried to add some GUI elements like an ImageView or a TextView to a LinearLayout programmatically. But the elements aren't displayed.
To see if a element is drawn or not, I set a different background color for each element. The result was that I can only see the background color of the LinearLayout. But why?
public class MyLinearLayout extends LinearLayout {
public MyLinearLayout(Context context) {
super(context);
LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT);
setLayoutParams(params);
setBackgroundColor(Color.RED);
imageView = new ImageView(context);
params = new LinearLayout.LayoutParams(100, 100);
imageView.setLayoutParams(params);
imageView.setBackgroundColor(Color.BLUE);
addView(imageView);
}
}
The strange thing is that I can see the red background color of the LinearLayout but in the size of the ImageView. If I add some other GUI elements like a TextView, I can see how the LinearLayout grows. But I can not see the TextView.
I'm really confused, because this not the first time I do something like this. Can u tell me what I'm doing wrong?
This is a snippet of the layout.xml file:
<LinearLayout android:layout_width="match_parent"
android:layout_height="45dp"
android:id="#+id/bottom_bar"
android:layout_alignParentBottom="true"
android:gravity="bottom">
<FrameLayout android:id="#+id/block_edit_delete_layout"
android:layout_height="match_parent"
android:layout_width="wrap_content"
android:background="#drawable/block_edit_delete_selector">
<ImageView android:layout_height="match_parent"
android:layout_width="wrap_content"
android:src="#drawable/block_edit_delete"
android:scaleType="fitXY"
android:contentDescription="#string/delete"/>
</FrameLayout>
<LinearLayout
android:id="#+id/block_edit_progress"
android:layout_height="match_parent"
android:layout_width="0dp"
android:layout_weight="1"
android:gravity="center"
android:orientation="horizontal"/>
<FrameLayout android:id="#+id/block_edit_random_layout"
android:layout_height="match_parent"
android:layout_width="wrap_content"
android:background="#drawable/block_edit_delete_selector">
<ImageView android:layout_height="match_parent"
android:layout_width="wrap_content"
android:src="#drawable/block_edit_random"
android:scaleType="fitXY"
android:contentDescription="#string/random_numbers"/>
</FrameLayout>
</LinearLayout>
The LinearLayout with the ID block_edit_progress is the container layout of multiple instances of the class MyLinearLayout. The instances are added in the code:
for(int i = 0; i < numberOfMyLinearLayouts; i++) {
MyLinearLayout v = new MyLinearLayout(getContext());
addView(v);
}
I hope this helps.

If i convert your code to xml, it would be something like:
<LinearLayout layout_width=wrap_content, layout_height = wrap_content>
<LinearLayout id= MyLinearLayout>//just an idea, syntax may be wrong
<LinearLayout layout_width= 100, layout_width=100>
<ImageView color=BLUE>
</ImageView>
</LinearLayout>
</LinearLayout>
</LinearLayout>
Whenever you call setLayoutParams on a View, parameter params you give should be parent element.
Try something like if you want linearlayout to be the parent of your linearlayout, use MATCH_PARENT for width, height if you want your view to span the width, height of view's parent
LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(
ViewGroup.LayoutParams.MATCH_PARENT,
ViewGroup.LayoutParams.MATCH_PARENT);
setLayoutParams(lp);//lp is parent view
Also try this, just in case views are getting added to right of your views, and you are not able to see them on screen
yourview.setOrientation(LinearLayout.VERTICAL);

Change the width and height of linear layout to match_parent and see how it changes. wrap_content will only show the content of the linear layout, which seems to be your problem.

I solved the problem. (Or found a workaround)
I moved the complete initialization stuff out of the constructor of the MyLinearLayout. If I then adding a View after the layout has been completely generated, everything works.
Like this:
MyLinearLayout ll = new MyLinearLayout(getContext());
LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(100, 100);
ll.setLayoutParams(params);
ll.setBackgroundColor(Color.RED);
ImageView v = new ImageView(getContext());
params = new LinearLayout.LayoutParams(50, 50);
v.setLayoutParams(params);
v.setBackgroundColor(Color.GREEN);
ll.addView(v);
addView(ll);
I don't know why the other way doesn't work. Thanks for the fast answers!

Android - Set FrameLayout width dynamically

I've got a FrameLayout which I want to grow as time continues.
I've implemented a Runnable-Interface.
public void run() {
time_value++;
FrameLayout fl_dateTime = (FrameLayout)findViewById(R.id.game_DateTime);
LayoutParams lp_fl_dateTime = fl_dateTime.getLayoutParams();
lp_fl_dateTime.width = time_value;
handler.postDelayed(this, 100);
}
Why doesn't this work? O_O

You need to set the layout params back after modifying them.
View#setLayoutParams(ViewGroup.LayoutParams lp)

I was able to do this by setting the initial size of the frame to 0dp and then just setting the minWidth to whatever I wanted.
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="0dp"
android:layout_height="fill_parent"
android:background="#android:color/black"
android:id="#id/layout"
android:minHeight="50dp"
android:measureAllChildren="false">
item.setMinimumWidth(10dp);