We can set a margin to a JButton by using the setMargin() method of JButton class and pass Insets(int top, int left, int bottom, int right) as an argument.
margin); int marginTopPx = (int) (marginTopDp * getResources(). getDisplayMetrics(). density + 0.5f); layoutParams. setMargins(0, marginTopPx, 0, 0); recyclerView.
Here is a little code to accomplish it:
LinearLayout ll = new LinearLayout(this);
ll.setOrientation(LinearLayout.VERTICAL);
LinearLayout.LayoutParams layoutParams = new LinearLayout.LayoutParams(
LinearLayout.LayoutParams.MATCH_PARENT, LinearLayout.LayoutParams.WRAP_CONTENT);
layoutParams.setMargins(30, 20, 30, 0);
Button okButton=new Button(this);
okButton.setText("some text");
ll.addView(okButton, layoutParams);
So that works fine, but how on earth do you give the buttons margins so there is space between them?
You call setMargins()
on the LinearLayout.LayoutParams
object.
I tried using LinearLayout.MarginLayoutParams, but that has no weight member so it's no good.
LinearLayout.LayoutParams
is a subclass of LinearLayout.MarginLayoutParams
, as indicated in the documentation.
Is this impossible?
No.
it wouldn't be the first Android layout task you can only do in XML
You are welcome to supply proof of this claim.
Personally, I am unaware of anything that can only be accomplished via XML and not through Java methods in the SDK. In fact, by definition, everything has to be doable via Java (though not necessarily via SDK-reachable methods), since XML is not executable code. But, if you're aware of something, point it out, because that's a bug in the SDK that should get fixed someday.
To add margins directly to items (some items allow direct editing of margins), you can do:
LayoutParams lp = ((ViewGroup) something).getLayoutParams();
if( lp instanceof MarginLayoutParams )
{
((MarginLayoutParams) lp).topMargin = ...;
((MarginLayoutParams) lp).leftMargin = ...;
//... etc
}
else
Log.e("MyApp", "Attempted to set the margins on a class that doesn't support margins: "+something.getClass().getName() );
...this works without needing to know about / edit the surrounding layout. Note the "instanceof" check in case you try and run this against something that doesn't support margins.
Due to variation in device screen pixel densities its good to always use DIP
unit to set margin programmatically. Like below_
//get resources
Resources r = getResources();
float pxLeftMargin = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 10, r.getDisplayMetrics());
float pxTopMargin = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 10, r.getDisplayMetrics());
float pxRightMargin = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 10, r.getDisplayMetrics());
float pxBottomMargin = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 20, r.getDisplayMetrics());
//get layout params...
LayoutParams params=new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT);
params.setMargins(Math.round(pxLeftMargin), Math.round(pxTopMargin), Math.round(pxRightMargin), Math.round(pxBottomMargin));
//set margin...
yourLayoutTOsetMargin.setLayoutParams(params);
Hope this will help.
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With