Android: How to Programmatically set the size of a Layout

You can get the actual height of called layout with this code:

public int getLayoutSize() {
// Get the layout id
    final LinearLayout root = (LinearLayout) findViewById(R.id.mainroot);
    final AtomicInteger layoutHeight = new AtomicInteger();

    root.post(new Runnable() { 
    public void run() { 
        Rect rect = new Rect(); 
        Window win = getWindow();  // Get the Window
                win.getDecorView().getWindowVisibleDisplayFrame(rect);

                // Get the height of Status Bar
                int statusBarHeight = rect.top;

                // Get the height occupied by the decoration contents 
                int contentViewTop = win.findViewById(Window.ID_ANDROID_CONTENT).getTop();

                // Calculate titleBarHeight by deducting statusBarHeight from contentViewTop  
                int titleBarHeight = contentViewTop - statusBarHeight; 
                Log.i("MY", "titleHeight = " + titleBarHeight + " statusHeight = " + statusBarHeight + " contentViewTop = " + contentViewTop); 

                // By now we got the height of titleBar & statusBar
                // Now lets get the screen size
                DisplayMetrics metrics = new DisplayMetrics();
                getWindowManager().getDefaultDisplay().getMetrics(metrics);   
                int screenHeight = metrics.heightPixels;
                int screenWidth = metrics.widthPixels;
                Log.i("MY", "Actual Screen Height = " + screenHeight + " Width = " + screenWidth);   

                // Now calculate the height that our layout can be set
                // If you know that your application doesn't have statusBar added, then don't add here also. Same applies to application bar also 
                layoutHeight.set(screenHeight - (titleBarHeight + statusBarHeight));
                Log.i("MY", "Layout Height = " + layoutHeight);   

            // Lastly, set the height of the layout       
            FrameLayout.LayoutParams rootParams = (FrameLayout.LayoutParams)root.getLayoutParams();
            rootParams.height = layoutHeight.get();
            root.setLayoutParams(rootParams);
        }
    });

return layoutHeight.get();
}

Java

This should work:

// Gets linearlayout
LinearLayout layout = findViewById(R.id.numberPadLayout);
// Gets the layout params that will allow you to resize the layout
LayoutParams params = layout.getLayoutParams();
// Changes the height and width to the specified *pixels*
params.height = 100;
params.width = 100;
layout.setLayoutParams(params);

If you want to convert dip to pixels, use this:

int height = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, <HEIGHT>, getResources().getDisplayMetrics());

Kotlin

LinearLayout YOUR_LinearLayout =(LinearLayout)findViewById(R.id.YOUR_LinearLayout)
    LinearLayout.LayoutParams param = new LinearLayout.LayoutParams(
                       /*width*/ ViewGroup.LayoutParams.MATCH_PARENT,
               /*height*/ 100,
               /*weight*/ 1.0f
                );
                YOUR_LinearLayout.setLayoutParams(param);

my sample code

wv = (WebView) findViewById(R.id.mywebview);
wv.getLayoutParams().height = LayoutParams.MATCH_PARENT; // LayoutParams: android.view.ViewGroup.LayoutParams
// wv.getLayoutParams().height = LayoutParams.WRAP_CONTENT;
wv.requestLayout();//It is necesary to refresh the screen