android popup dialog from activity code example

Example 1: android dialog box example

runOnUiThread(new Runnable() {
    @Override
    public void run() {

        if (!isFinishing()){
            new AlertDialog.Builder(YourActivity.this)
              .setTitle("Your Alert")
              .setMessage("Your Message")
              .setCancelable(false)
              .setPositiveButton("ok", new OnClickListener() {
                  @Override
                  public void onClick(DialogInterface dialog, int which) {
                      // Whatever...
                  }
              }).show();
        }
    }
});

Example 2: alert dialog layout

View customLayout = LayoutInflater.from(MainActivity.this).inflate(R.layout.custom_dialog, null);

final TextInputLayout editMessage = customLayout.findViewById(R.id.edit_message);

AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this)
        .setView(customLayout)
        .setPositiveButton("Submit", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialogInterface, int i) {
                String message = Objects.requireNonNull(editMessage.getEditText()).getText().toString();

                // Dismiss Dialog
                dialogInterface.dismiss();

                Toast.makeText(MainActivity.this, message, Toast.LENGTH_SHORT).show();
            }
        })
        .setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialogInterface, int i) {
                dialogInterface.cancel();
            }
        });
builder.show();