I keep either removing import.R or adding mypackage.R or deleting all imports and shift-control O
or deleting R.java.
I still get the error: main.xml cannot be resolved or alternately, R cannot be resolved to a variable. I have cleaned each time. How do you get this to work?
package com.hga;
import android.app.Activity;
import android.content.Intent;
import android.view.Menu;
import android.view.View;
import android.widget.Button;
public class Hga extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView( R.layout.activity_hga );
Yeah i used to run into those type of problems when i was starting programing for android. The R folder updates itself everytime code is written or saved and when a error occurs in your code for whatver reason it may be the R folder gives you that error report. At first clean but if that doesnt work as it usually wont you want to completely coment out your code /* .... */
then clean and the error should go way now you can pin point which bit of code is causing the error to occur in the R folder.
PS. this was my main source of frustration in coding android apps
Related
Since quite some time now I am not able to solve this issue. Somehow the package in my flutter project 'package:share_plus_web/share_plus_web.dart' is underlined in red color. This is the code within the explorer:
// Generated file. Do not edit.
//
// ignore_for_file: directives_ordering
// ignore_for_file: lines_longer_than_80_chars
import 'package:cloud_firestore_web/cloud_firestore_web.dart';
import 'package:firebase_core_web/firebase_core_web.dart';
import 'package:firebase_storage_web/firebase_storage_web.dart';
import 'package:flutter_native_timezone/flutter_native_timezone_web.dart';
import 'package:share_plus_web/share_plus_web.dart';
import 'package:url_launcher_web/url_launcher_web.dart';
import 'package:flutter_web_plugins/flutter_web_plugins.dart';
// ignore: public_member_api_docs
void registerPlugins(Registrar registrar) {
FirebaseFirestoreWeb.registerWith(registrar);
FirebaseCoreWeb.registerWith(registrar);
FirebaseStorageWeb.registerWith(registrar);
FlutterNativeTimezonePlugin.registerWith(registrar);
SharePlusPlugin.registerWith(registrar);
UrlLauncherPlugin.registerWith(registrar);
registrar.registerMessageHandler();
}
And it says "Do not edit." So I'm not sure if I can just adjust things here in the code?
I also added a screenshot, hope that helps:
Thanks a lot in advance!
I currently have a problem changing the layout of my Android app. It doesn't work like usual.
When I want to change the layout to the settings layout with the press of a button, it gives the error: cannot find symbol variable Settings_main.
The code where this happens is
final ImageButton settings = findViewById(R.id.Settings_button);
settings.setOnCLickListener(new View.onClickListener() {
#Override
public void onClick(View v) {
setContentView(R.layout.Settings_main);
}
});
This is the error it's giving me
I have imported
import android.view.View;
import androidx.appcompat.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.ImageButton;
Can someone please help me solve this?
Every name and Id does match according to IntelliJ as well, so I have no idea what could possibly be going wrong.
File-based resource names must contain only lowercase a-z,0-9 or underscore.
Please change file name Settings_main to settings_main
Trying out some android programming that has gone fine up until this point. I'm getting the following errors:
Activity cannot be resolved to a type
The import Activity cannot be resolved
on the top two imports (activity and bundle) of the following class:
package com.example.sqlite;
import android.app.Activity;
import android.os.Bundle;
import android.widget.Button;
import android.widget.EditText;
public class Input extends Activity {
private EditText txtTitle;
private EditText txtURL;
private Button btnOK;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.input);
txtTitle = (EditText) findViewById(R.id.editText1);
txtURL = (EditText) findViewById(R.id.editText2);
btnOK = (Button) findViewById(R.id.button1);
}
}
I've done the standard ctrl + shift + O, which does automatically add these imports but the errors remain. I've also rebuilt it over and over with no effect.
Ca anyone see were I'm going wrong here?
Do right click on the project node in Eclipse and select Android Tools->Fix Project Properties. It looks like you are missing link to your Android libraries. Good way to check on that is to open properties-> Java build path -> Libraries and verify that Android link is there. If not - do Properties->Android and select project target you would like to use
You may occasionally see strange erros if any of your XML files fail to build. Check your console to see if any of your layout or resources have errors. Do the following:
Project > Clean
If this does not fix it, verify that pour souce actually exists in the project path:
com.example.sqlite
Check your manifest xml if the activity is included.. This can sometimes cause the error.
I Wrote the Following code :
package com.aamir.cool;
import android.app.*;
import android.os.*;
import android.view.*;
import android.widget.*;
public class MainActivity extends Activity
{
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
ImageView img = (ImageView)findViewById(R.id.facebook);
img.setOnClickListener(new View.OnClickListener(){
public void onClick(View v){
Intent intent = new Intent();
intent.setAction(Intent.ACTION_VIEW);
intent.addCategory(Intent.CATEGORY_BROWSABLE);
intent.setData(Uri.parse("http://www.facebook.com/exandrok?ref=tn_tnmn"));
startActivity(intent);
}
});
}
}
I am getting error "Unknown Entity Intent" , "Unknown type of variable intent" .
How to Solve these Error ?
Add the following lines to your import statements:
import android.content.Intent;
import android.net.Uri;
Add the correct import statements
import android.content.Intent
import android.net.Uri;
If you're using Eclipse, you can add/organise/optimise your imports with the following shortcut
Cmd-shift-O on OSX
Ctrl+Shift+O on Windows / Linux
Rawkode Still Getting 2 Error : " Unknown entity 'uri" and "Unknown
member 'main of 'com.aamir.cool.R.id"
Please ensure that main.xml actually exists in your layout folder.
After importing the android.content.Intent; first check your xml files and be sure you dont have any layout problems and delete your R.java file and let it generate that again. after doing that right click to your project Android Projects -> Fix Project Properties then select "Project" and click "Clear" then try to run the code again. if still not working ctrl+a ctrl+x and ssave the file be sure you have no errors and ctrl+v again and try to run again.
Try verifying the AndriodManifest.xml in the main page which generates the package as seen in the gen/com folders
Suddenly my buttons cause null pointer exceptions. I have not changed any code in this activity class. I have been up most of the weekend trying to pin this down. I get null pointer exceptions in both the emulator and on device.
This is a simple screen with buttons. I could easily scrap this and write new code, but would like to know what has caused this issue. If not, I will just write new code.
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
Button b1 = (Button) findViewById(R.id.MainActBtn);
b1.setOnClickListener(new View.OnClickListener() { //Error is here
public void onClick(View v) {
Intent intent = new Intent(StartScreen.this, MainActivity.class);
startActivity(intent);
}
});
Any help?
Try a fresh clean and build of your project. I got this error too in the past, caused by a changed R.class Resource class, but the static references in the using classes weren't properly replaced by the incremental java compiler, so the resources are no longer found.
I think You are not getting Null Pointer Exception because of the Button click just because of the declaration of the button..
You can check before writting the onClickListener..
if(b1==null)
Log.i("Null","Null");
The Problem is may be in setting the XML view or also check the button you are using is defined in the same xml you are using in setContentView.
After this all, also Clean and Build your project.