search text on WebView android

Question

I have a webview in my activity ,

it's worked if press "enter" on keyboard . but if press button "searsh" not worked

https://i.stack.imgur.com/TXHZY.jpg

i use this code :

findBox = new EditText(this);  
findBox.setMinEms(30);  
findBox.setSingleLine(true);  
findBox.setHint("");  

nextButton = new Button(this);  
nextButton.setText("search");  
nextButton.setOnClickListener(new OnClickListener(){  
@Override  
public void onClick(View v){  
mWebView.findNext(true);  

}  
});  
container.addView(nextButton);  

findBox.setOnKeyListener(new OnKeyListener(){  
public boolean onKey(View v, int keyCode, KeyEvent event){  
if((event.getAction()  == KeyEvent.ACTION_DOWN) && 
        (keyCode == KeyEvent.KEYCODE_ENTER)){  
mWebView.findAllAsync(findBox.getText().toString());  

try{  
Method m = WebView.class.getMethod("setFindIsUp", Boolean.TYPE);  
m.invoke(mWebView, true);  
}catch(Exception ignored){}  
}  
return false;  
}  
});  

container.addView(findBox);  
}  
}