Open soft keyboard programmatically

I have used the following lines to display the soft keyboard manually inside the onclick event, and the keyboard is visible.

InputMethodManager inputMethodManager =
    (InputMethodManager)getSystemService(Context.INPUT_METHOD_SERVICE);
inputMethodManager.toggleSoftInputFromWindow(
    linearLayout.getApplicationWindowToken(),
    InputMethodManager.SHOW_FORCED, 0);

But I'm still not able to open this while the activity gets opened, so are there any solution for this?

This is works

<activity
    ...
    android:windowSoftInputMode="stateVisible" >
</activity>

or

getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_VISIBLE);

Please follow the below code. I am sure your problem will be solved.

if (imm != null){
        imm.toggleSoftInput(InputMethodManager.SHOW_FORCED,0);
   } 

In your manifest file, try adding the following to the <activity> that you want to show the keyboard when the activity starts:

android:windowSoftInputMode="stateVisible"

This should cause the keyboard to become visible when the activity starts.

For more options, checkout the documentation.