Develop Reference

Is there a way to copy constraint parameters of a component in ConstraintLayout?

I have a View in my ConstraintLayout which is positioned in XML. Then I want to change this view to another view on button click. I have the script to do it and it works OK, but the new View appears at the top of the screen and I need it to be in the same position as the previous. I've read Google Android documentation, but nothing I found seems to help me. Is the only way to do it is by using ConstraintSet.connect()?

You can do this by re-using the original view's ConstraintLayout.LayoutParams object:
button.setOnClickListener(v -> {
ConstraintLayout.LayoutParams params =
(ConstraintLayout.LayoutParams) viewToRemove.getLayoutParams();
parent.removeView(viewToRemove);
parent.addView(viewToAdd, params);
});
Note that this will give the same width and height as the old view as well, so you may have to explicitly set those if you need them to be different:
ConstraintLayout.LayoutParams params =
(ConstraintLayout.LayoutParams) toRemove.getLayoutParams();
params.width = ViewGroup.LayoutParams.WRAP_CONTENT;
params.height = ViewGroup.LayoutParams.WRAP_CONTENT;

How to fix right button border not showing in app?

I am trying to make a game with multiple levels. My plan is to print 15 levels on 1 page. I have attached a photo of the simple design I am currently using.
As you can see in the picture the right border of a button is not showing. For the parent I am using this java code:
LinearLayout horl = new LinearLayout(this);
horl.setId(worldVar);
horl.setOrientation(LinearLayout.HORIZONTAL);
horl.setLayoutParams(new LinearLayout.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT,
ViewGroup.LayoutParams.WRAP_CONTENT));
And to set 3 buttons horizontally in this LinearLayout I use this code for the buttons. This code just has a simple for loop around to put 3 buttons in this LinearLayout:
Button button = new Button(this);
LinearLayout.LayoutParams params = new LinearLayout
.LayoutParams(getMarginInDp(100), getMarginInDp(100));
params.setMargins(getMarginInDp(1), getMarginInDp(25), getMarginInDp(1), 0);
button.setLayoutParams(params);
GradientDrawable gd = new GradientDrawable();
gd.setCornerRadius(5);
gd.setStroke(1, 0xFF000000);horl.addView(button);
The function getMarginInDp looks like this:
public int getMarginInDp(int dp){
return (int) TypedValue
.applyDimension(TypedValue.COMPLEX_UNIT_DIP, dp, getResources().getDisplayMetrics());
}
Does anybody have any idea how to make the border appear because I want to keep the buttons approximately this size and I may even slightly increase the margins?

You can set the weight to 0.33f for each button:
Button button = new Button(this);
LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(getMarginInDp(100), getMarginInDp(100), 0.33f);
so they are distributed equally in the width of the layout.

Android Studio - issue with manipulating Layouts/Views programmatically

I have a few issues with setting LayoutParams and other parameters of my layouts/views programmatically. I cannot specify these in a XML layout file because whether they appear depends on the data held in the database.
The following is a function I use to create a new "Section" which consists of a FrameLayout with its children being View and TextView:
public FrameLayout createSection(long id, String name) {
FrameLayout frame = new FrameLayout(this);
LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT, 100);
params.setMargins(15, 15, 15, 15);
frame.setLayoutParams(params);
View view = new View(this);
LayoutParams viewParams = new LayoutParams(LayoutParams.MATCH_PARENT, 100);
view.setLayoutParams(viewParams);
view.setId(toIntExact(id));
view.setBackgroundResource(R.color.colorButton);
frame.addView(view);
TextView text = new TextView(this);
LayoutParams textParams = new LayoutParams(LayoutParams.MATCH_PARENT, 100);
textParams.setMarginStart(15);
text.setGravity(Gravity.CENTER);
text.setTextAlignment(TextView.TEXT_ALIGNMENT_TEXT_START);
text.setTextColor(getResources().getColor(R.color.colorTextSecondary));
text.setText(name);
frame.addView(text);
return frame;
}
The parent of this newly created FrameLayout is LinearLayout and so based on the other similar questions on StackOverflow I figured setting parameters for FrameLayout should be done through LinearLayout.LayoutParams. However, this does not make a change. The initial XML page contains this:
Initial XML page
The first "SECTION" is created in the XML file, and the other two are created through 'createSection' function. This is the outcome: Design outcome
The issue is that the margins are not set properly and the TextView doesn't seem to care about the Gravity + TextAlignment combination that I'm using.
I would appreciate any help that I could get to resolve this issue.

I apologise for wasting anyone's time. The code seems to work and the margin sizes are different due to these being set in terms of pixels (px) rather than dp as it is in the XML file.
I also forgot to add text.setLayoutParams(textParams); to the TextView object.

Issue with Button in AlertDialog (Floating off screen)

Here's an image of what my issue looks like:
That box at the bottom is the top half of a button. Whenever I've got too many Stock Options in the dialog box, it first forces the button off screen, THEN it scrolls.
I want the button fixed at the bottom of the dialog and then have the scrolling happen.
Here's the code:
public void buyStock(View view){
Context context = getApplicationContext();
//create ScrollView to hold everything
ScrollView scrollView = new ScrollView(context);
//generate content for dialog
LinearLayout dialogContainer = new LinearLayout(context);
dialogContainer.setOrientation(LinearLayout.VERTICAL);
LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT, 400, 1);
dialogContainer.setLayoutParams(params);
dialogContainer.setPadding(15, 15, 0, 15);
dialogContainer.setBackgroundColor(Color.WHITE);
//each hotel stock options
for (int i = 0; i < hotels.size(); i++) {
Hotel testHotel = hotels.get(i);
testHotel.setPrice(200);
View stockPicker = getStockPicker(testHotel);
LinearLayout.LayoutParams pickerParams = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT, 100, 1.0f);
pickerParams.gravity = Gravity.LEFT;
stockPicker.setLayoutParams(pickerParams);
dialogContainer.addView(stockPicker);
stockPicker.setBackgroundColor(0xffffff);
}
scrollView.addView(dialogContainer);
LinearLayout dialogLayout = new LinearLayout(context);
dialogLayout.setOrientation(LinearLayout.VERTICAL);
Button buyButton = new Button(context);
LinearLayout.LayoutParams buttonParams = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT, 100);
buyButton.setLayoutParams(buttonParams);
LinearLayout buttonLayout = new LinearLayout(context);
buttonLayout.addView(buyButton);
dialogLayout.addView(scrollView);
dialogLayout.addView(buttonLayout);
ContextThemeWrapper ctw = new ContextThemeWrapper(this, R.style.AppTheme);
AlertDialog.Builder buyStockDialog = new AlertDialog.Builder(ctw);
buyStockDialog.setTitle("Buy Stock: ");
buyStockDialog.setView(dialogLayout);
buyStockDialog.show();
}

Make dialogLayout a RelativeLayout, and then declare buttonParams as a RelativeLayout.LayoutParams (layout params are declared according the parent viewgroup type, which for buyButton is now a RelativeLayout). Your also going to need to declare a RelativeLayout.LayoutParams for scrollView.
note: This code is in c#/monodroid, not raw java/android, so some quick porting of some of the methods and constants may need to be required, but shouldn't be too time consuming.
If this doesn't work out exactly trying experimenting with other combinations of the RelativeLayout position rules and/or gravity. Let me know if it doesn't work out.
RelativeLayout.LayoutParams scrollParams = new RelativeLayout.LayoutParams(LayoutParams.WRAP_CONTENT, some_height);
RelativeLayout.LayoutParams buttonParams = new RelativeLayout.LayoutParams(LayoutParams.MATCH_PARENT, 100);
Then, add these statements to control where scrollView and buyButton are positioned
scrollParams.AddRule(LayoutRules.AlignParentLeft);
scrollParams.AddRule(LayoutRules.AlignParentTop);
buttonParams.AddRule(LayoutRules.Below, scrollView.Id);
The for the getting the button on the bottom of the screen, try one of two things
buttonParams.AddRule(LayoutRules.AlignParentBottom);
or
buyButton.Gravity = Gravity.BOTTOM

Try explicitly setting a fixed height to the scrollView
scrollView.LayoutParameters.Height = HEIGHT;
I think it defaults to WRAP_CONTENT if not specified, and is why its scaling.
You may have to set it in a layout file if you cant from code
<ScrollView
android:id="#+id/scroll_view_1
android:layout_width="wrap_content"
android:layout_height="100"/>
and then change
ScrollView scrollView = new ScrollView(context);
to
ScrollView scrollView = findViewById(R.Id.scroll_view_1, this);

Try wrapping the scrollView in another LinearLayout, and set this new layout's height to a fixed width that keeps the button low enough to your liking. You can actually replace the Scrollview with a ListView, but don't do this until after at least trying to get this fix working first. ListViews scroll, but you'd still face this problem without this fix.
To fix the new issue you mentioned below (with some quick and dirty code, you should use trial and error to fix it correctly), try the following
//each hotel stock options
for (int i = 0; i < hotels.size(); i++)
{
// ...
}
if( hotels.size() < numberOfItemsNeededForCorrectView )
{
for( int i=0; i < numberOfItemsNeededForCorrectView - hotels.size(); i++ )
{
View blankView = new View(context);
LinearLayout.LayoutParams viewParams = new LinearLayout.LayoutParams(1, 100);
blankView.setLayoutParams(viewParams);
blankView.setViewState(ViewState.INVISIBLE);
dialogContainer.addView(stockPicker);
}
}
You can try replacing your scrollView with a list view still and see if that fixes things. You can also try tweaking layout and gravity settings until you get it, or trying introducing other layouts or reorganizing your layouts (or using RelativeLayout, its really not that bad).

So, now in 2022 I've also had this problem. I've just set fixed size for ScrollView in fragment layout xml-file. When you have this problem, you can set, for example, 150dp or 200dp and be happy! And for more convenience, you can create special layout for landscape screen orientation and set fixed layout_height size there. I'm really confused that there's no information about this problem besides this page on the Internet.
<ScrollView
android:layout_width="match_parent"
android:layout_height="200dp">
<!--your view into scrollView here-->
</ScrollView>

Android: Setting the Weight parameter programmatically does the opposite of what i want

I'm having a problem with android.
I'm setting the Weight parameter in Java, but it's doing exactly the oposite of what I want.
Here's the code
LinearLayout container = new LinearLayout(context);
// some code ...
container.setWeightSum(1f);
View v1 = new View(context);
v1.setBackgroundColor(Color.parseColor("#ff0000"));
LinearLayout.LayoutParams p1 = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT,LinearLayout.LayoutParams.WRAP_CONTENT);
p1.weight=0.1f;
View v2 = new View(context);
v2.setBackgroundColor(Color.parseColor("#000000"));
LinearLayout.LayoutParams p2 = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT,LinearLayout.LayoutParams.WRAP_CONTENT);
p2.weight=0.9f;
container.addView(v1,p1);
container.addView(v2,p2);
I repeat this process 7 times with adding a black line between the container layout.
Normally I should get a small red column on the lef, and a large black one, but here's what I get with this code :
Why does it doing exactly the opposite of the code ?

When we use the weight width should be Zero
try with width 0 for with children inside the container.............
LinearLayout.LayoutParams p1 = new LinearLayout.LayoutParams(0,LinearLayout.LayoutParams.WRAP_CONTENT);
LinearLayout.LayoutParams p2 = new LinearLayout.LayoutParams(0,LinearLayout.LayoutParams.WRAP_CONTENT);

You are setting both widths to "wrap_content"... when using weights you should set the affected orientation to "0dp" (or it's programatic equivalent).