Android: How to add Buttons to a Layout programmatically(with Buttons to be seen in the XML-View)
as the title states, i do want to add Buttons to a ConstraintLayout programmaticaly, whic implies, added Buttons are to be seen within the XML-File.
XML File:
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:app="http://schemas.android.com/apk/res-auto" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" tools:context=".MainActivity" android:id="@+id/idMain"> </androidx.constraintlayout.widget.ConstraintLayout> Code for adding Buttons:
ConstraintLayout cst = (ConstraintLayout) findViewById(R.id.idMain); Button btn = new Button(this); btn.setText("Hallo Welt"); cst.addView(btn); Issue: Added Button is nowhere to be seen within the XML-File. Question: How to append the Button to the XML-File ?
UP
try it:
ConstraintLayout cst = (ConstraintLayout)findViewById(R.id.idMain); ConstraintSet set = new ConstraintSet(); Button btn = new Button(this); // set view id, else getId() returns -1 btn.setId(View.generateViewId()); cst.addView(btn, 0); set.clone(cst); set.connect(btn.getId(), ConstraintSet.TOP, cst.getId(), ConstraintSet.TOP, 60); set.applyTo(cst); How to programmatically add views and constraints to a ConstraintLayout?
Use this code XML
<android.support.constraint.ConstraintLayout android:id="@+id/ly_id" android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_marginBottom="10dp" android:layout_marginLeft="10dp" android:layout_marginRight="10dp" android:layout_marginTop="0dp"> </android.support.constraint.ConstraintLayout> Java code to add button programetically.
ConstraintLayout layout = (ConstraintLayout) findViewById(R.id.ly_id); //set the properties for button Button btnTag = new Button(this); btnTag.setText("Button"); btnTag.setId(some_random_id); //add button to the layout layout.addView(btnTag); 
