Resource cannot be resolved or is not a field?

Resource cannot be resolved or is not a field? - android

I copy pasted everything from a tutorial, 3 of them saved, but weird thing happened.
It said my Chronometer and button cannot be resolved or is not a field.
StopWatch.java
package com.example.stopwatch2;
import android.os.Bundle;
import android.os.SystemClock;
import android.app.Activity;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.Chronometer;
public class StopWatch extends Activity {
Chronometer mChronometer;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_stop_watch);Button button;
mChronometer = (Chronometer) findViewById(R.id.chronometer);
// Watch for button clicks.
button = (Button) findViewById(R.id.start);
button.setOnClickListener(mStartListener);
button = (Button) findViewById(R.id.stop);
button.setOnClickListener(mStopListener);
button = (Button) findViewById(R.id.reset);
button.setOnClickListener(mResetListener);
}
View.OnClickListener mStartListener = new OnClickListener() {
public void onClick(View v) {
mChronometer.start();
}
};
View.OnClickListener mStopListener = new OnClickListener() {
public void onClick(View v) {
mChronometer.stop();
}
};
View.OnClickListener mResetListener = new OnClickListener() {
public void onClick(View v) {
mChronometer.setBase(SystemClock.elapsedRealtime());
}
};
#Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.activity_stop_watch, menu);
return true;
}
}
activity_stop_watch.xml:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:padding="4dip"
xmlns:tools="http://schemas.android.com/tools"
android:gravity="center_horizontal"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<Chronometer android:id="#+id/chronometer"
android:format="#string/chronometer_initial_format"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="0"
android:paddingBottom="30dip"
android:paddingTop="30dip"
/>
<Button android:id="#+id/start"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Start">
<requestFocus />
</Button>
<Button android:id="#+id/stop"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Stop">
</Button>
<Button android:id="#+id/reset"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Reset">
</Button>
</LinearLayout>
string.xml:
<?xml version="1.0" encoding="utf-8"?>
<resources xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2">
<string name="hello">Hello World, StopWatch!</string>
<string name="app_name">StopWatch</string>
<string name="chronometer_initial_format">Initial format:<xliff:g id="initial-format">%</xliff:g></string>
</resources>
Can anyone tell me what is wrong here?

Try cleaning your project. Right click on your project and say 'clean'. Then try running your app again.
Also, another tip. Don't use the same variable names for all the buttons. Use different names like this:
// Watch for button clicks.
buttonStart = (Button) findViewById(R.id.start);
button.setOnClickListener(mStartListener);
buttonStop = (Button) findViewById(R.id.stop);
button.setOnClickListener(mStopListener);
buttonReset = (Button) findViewById(R.id.reset);
button.setOnClickListener(mResetListener);
Your code will be easier to manage and debug in the long run.

Related

Android app is not running on android studio and going to force close

i am new at android app development. i made a simple app in which text changes whenever button is clicked but whenever i run it the app going to force close. kindly help .
Following is my XML
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/activity_main"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
tools:context="com.progneers.www.app.MainActivity">
<TextView
android:text="#string/txtString"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:layout_marginTop="41dp"
android:id="#+id/myTextView"
android:textAppearance="#style/TextAppearance.AppCompat" />
<Button
android:text="#string/click_me"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/myTextView"
android:layout_centerHorizontal="true"
android:layout_marginTop="100dp"
android:id="#+id/myButton" />
</RelativeLayout>
Following is my Java Code
package com.progneers.www.app;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
public class MainActivity extends AppCompatActivity {
private TextView myTextView = (TextView) findViewById(R.id.myTextView);
private Button myButton = (Button) findViewById(R.id.myButton);
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
myButton.setOnClickListener(
new Button.OnClickListener(){
public void onClick(View v){
myTextView.setText("Button Clicked! Thank You!");
}
}
);
}
}
Error shows after app closed

You have to assign the views in the onCreate, try this
public class MainActivity extends AppCompatActivity {
private TextView myTextView;
private Button myButton;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
myTextView = (TextView) findViewById(R.id.myTextView);
myButton = (Button) findViewById(R.id.myButton);
myButton.setOnClickListener(
new Button.OnClickListener(){
public void onClick(View v){
myTextView.setText("Button Clicked! Thank You!");
}
}
);
}
}

How to debug an Android app that says "unfortunately <app> stopped working"?

This is my java class, MainActivity.java.
Basically I'm trying to create a button performing addition on variable i. Everything seems to be correct as far as I learnt until now. I am getting an error message on my emulator saying:
unfortunately myfirstandroidapp stopped working.
Code:
package com.example.android.myfirstandroidapp;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.TextView;
import android.util.Log;
public class MainActivity extends AppCompatActivity {
int i = 0;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Button button = (Button) findViewById(R.id.addButton);
final TextView txtView = (TextView) findViewById(R.id.textView);
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
i++;
txtView.setText("i value is:"+i);
}
});
setContentView(R.layout.activity_main);
}
}
This is my layout.xml
main_activity.xml:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/activity_main"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
tools:context="com.example.android.myfirstandroidapp.MainActivity">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Your value is:0"
android:id="#+id/textView"
android:textColor="#android:color/black"
android:textStyle="normal|bold"
android:textSize="14dp" />
<Button
android:text="Add One"
android:layout_width="100dp"
android:layout_height="20dp"
android:layout_marginTop="25dp"
android:id="#+id/addButton"
android:background="#android:color/holo_green_dark"
android:layout_below="#+id/textView"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true" />
</RelativeLayout>

You need to call setContentView() before initializing any View.
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button button = (Button) findViewById(R.id.addButton);
final TextView txtView = (TextView) findViewById(R.id.textView);
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
i++;
txtView.setText("i value is:"+i);
}
});
}

How to configure a image pop up for android using eclipce?

I'm working with a list of ImageViews, while I would like to each one be clicked on, an image appear as a pop up.
Currently got a good result, but a lot of work, I created a new xml file for each image, so using onclicklistener, every time I click on ImageView, open another layout xml, but that I would like just open a pop up image.
Can anyone help me?
Here is may xml:
res/layout/main.xml
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent" >
<ScrollView
android:id="#+id/scrollView1"
android:layout_width="match_parent"
android:layout_height="353dp"
android:layout_marginTop="150dp" >
<LinearLayout
android:layout_width="match_parent"
android:layout_height="100dp"
android:orientation="vertical" >
<Button
android:id="#+id/button1"
android:layout_width="fill_parent"
android:layout_height="100dp"
android:text="#string/popup1" />
<Button
android:id="#+id/button2"
android:layout_width="fill_parent"
android:layout_height="100dp"
android:text="#string/popup2" />
<Button
android:id="#+id/button3"
android:layout_width="fill_parent"
android:layout_height="100dp"
android:text="#string/popup3" />
<Button
android:id="#+id/button4"
android:layout_width="fill_parent"
android:layout_height="100dp"
android:text="#string/popup4" />
<Button
android:id="#+id/button5"
android:layout_width="fill_parent"
android:layout_height="100dp"
android:text="#string/popup5" />
</LinearLayout>
</ScrollView>
</FrameLayout>
res/layout/aperitivos
<ImageView
android:id="#+id/ivcarnes"
android:layout_width="364dp"
android:layout_height="410dp"
android:layout_gravity="center"
android:contentDescription="#string/panecestino"
android:src="#drawable/panecestinoim" />
<Button
android:id="#+id/btclose"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="right"
android:layout_marginRight="85dp"
android:layout_marginTop="150dp"
android:text="#string/close"
android:textStyle="bold"/>
</FrameLayout>
Here is my code:
Main.java
import android.os.Bundle;
import android.app.Activity;
import android.content.Intent;
import android.view.Menu;
import android.view.View;
import android.widget.*;
public class Main extends Activity {
Button button1, button2, button3, button4, button5;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
button1 = (Button)
findViewById(R.id.button1);
button2 = (Button)
findViewById(R.id.button2);
button3 = (Button)
findViewById(R.id.button3);
button4 = (Button)
findViewById(R.id.button4);
button5 = (Button)
findViewById(R.id.button5);
button1.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View Arg0) {
Intent testegrafico = new
Intent(Main.this,Aperitivos.class);
Main.this.startActivity(testegrafico);
Main.this.finish();
}});
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.main, menu);
return true;
}}
Aperitivos.java
import android.os.Bundle;
import android.app.Activity;
import android.content.Intent;
import android.view.Menu;
import android.view.View;
import android.widget.*;
public class Aperitivos extends Activity {
Button btclose;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.aperitivos);
btclose = (Button)
findViewById(R.id.btclose);
btclose.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View Arg0) {
Intent testegrafico = new
Intent(Aperitivos.this,Main.class);
Aperitivos.this.startActivity(testegrafico);
Aperitivos.this.finish();
}
});
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}

package br.com.example.locandaristorante;
import android.os.Bundle;
import android.app.Activity;
import android.graphics.drawable.Drawable;
import android.view.Gravity;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewGroup;
import android.widget.*;
public class Main extends Activity {
Button button1, button2, button3, button4, button5;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
button1 = (Button)
findViewById(R.id.button1);
button2 = (Button)
findViewById(R.id.button2);
button3 = (Button)
findViewById(R.id.button3);
button4 = (Button)
findViewById(R.id.button4);
button5 = (Button)
findViewById(R.id.button5);
button1.setOnClickListener(new Button.OnClickListener() {
#Override
public void onClick(View arg0) {
View popupView = new View(Main.this);
final PopupWindow popupWindow = new PopupWindow(popupView,
ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT);
Drawable drawable = getResources().getDrawable(R.drawable.panecestinoim);
popupWindow.setBackgroundDrawable(drawable);
popupWindow.setHeight(600);
popupWindow.setWidth(400);
popupWindow.setTouchable(true);
popupWindow.setFocusable(true);
popupWindow.setTouchInterceptor(new View.OnTouchListener() {
#Override
public boolean onTouch(View v, MotionEvent event) {
// TODO Auto-generated method stub
popupWindow.dismiss();
return false;
}
});
popupWindow.showAtLocation(findViewById(R.id.button1), Gravity.CENTER, 0, 0);
}
});
}}

displaying a string on the textview when clicking a button in android

I'm very new to Android development and just started to study.
What I'm trying is to add a button and when that button is pressed a text "my first project" to get displayed in the text view.
With the help of some experts I created the button and text view.
So the button is showing in the simulator but when I click that button nothing happens.
Can anyone please help me with how can I display the text when pressing the button?
.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<TextView
android:id="#+id/txtView"
android:layout_width="150dp"
android:layout_height="150dp"
android:text="#string/hello" />
<Button
android:id="#+id/mybtn"
android:layout_width="50dp"
android:layout_height="30dp" />
<TextView
android:id="#+id/viewwidth"
android:layout_width="fill_parent"
android:layout_height="wrap_content" />
<TextView
android:id="#+id/viewheight"
android:layout_width="fill_parent"
android:layout_height="wrap_content" />
</LinearLayout>
.java
import android.app.Activity;
import android.os.Bundle;
import android.widget.Button;
import android.widget.TextView;
import android.view.View;
import android.widget.Toast;
public class NameonbuttonclickActivity extends Activity implements View.OnClickListener {
Button mybtn;
TextView txtView;
String hello;
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
setContentView(R.layout.main);
super.onCreate(savedInstanceState);
mybtn= new Button(this);
txtView=new TextView(this);
mybtn.setOnClickListener(this);
printmyname();
mybtn = (Button)findViewById(R.id.mybtn);
txtView=(TextView)findViewById(R.id.txtView);
txtView = (TextView)findViewById(R.id.viewwidth);
txtView = (TextView)findViewById(R.id.viewheight);
hello="This is my first project";
//setContentView(mybtn);
// setContentView(R.layout.main);
}
public void onClick(View view){
txtView.setText(hello);
//printmyname();
Toast.makeText(NameonbuttonclickActivity.this, hello, Toast.LENGTH_LONG).show();
}
private void printmyname(){
System.out.println("coming");
}
}

You can do like this:
String hello;
public void onCreate(Bundle savedInstanceState) {
setContentView(R.layout.main);
super.onCreate(savedInstanceState);
mybtn = (Button)findViewById(R.id.mybtn);
txtView=(TextView)findViewById(R.id.txtView);
txtwidth = (TextView)findViewById(R.id.viewwidth);
hello="This is my first project";
mybtn.setOnClickListener(this);
}
public void onClick(View view){
txtView.setText(hello);
}
Check your textview names. Both are same . You must use different object names and you have mentioned that textview object which is not available in your xml layout file.
Hope this will help you.

First create xml file as follows. Create one textview and a button:
main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="#string/hello" />
<Button
android:id="#+id/mybutton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Click Me" />
<TextView
android:id="#+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
/>
</LinearLayout>
The first TextView is created by default. You can leave or remove it if you want.
Next one is to create a button
The next one is TextView where you want to display text.
Now coming to the main activity code...
package com.android.example.simple;
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
public class SimpleActivity extends Activity {
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
final TextView textView=(TextView)findViewById(R.id.textView1);
final Button button1 = (Button)findViewById(R.id.mybutton);
//Implement listener for your button so that when you click the
//button, android will listen to it.
button1.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
// Perform action on click
textView.setText("You clicked the button");
} });
}
}

This is because you DON'T associated the OnClickListener() on the button retrieve from the XML layout.
You don't need to create object because they are already created by the Android system when you inflate XML file (with the Activity.setContentLayout( int resourceLayoutId ) method).
Just retrieve them with the findViewById(...) method.

Just check your code in .java class
You had written below line
mybtn.setOnClickListener(this);
before initializing the mybtn object I mean
mybtn = (Button)findViewById(R.id.mybtn);
just switch this two line or put that line "mybtn.setOnClickListener(this)" after initializing your mybtn object and you will get the answer what you want..

Try this
public void onClick(View view){
txtView.setText("hello");
//printmyname();
Toast.makeText(NameonbuttonclickActivity.this, "hello", Toast.LENGTH_LONG).show();
}
Also in toast use "Hello"

you use this as txtView.setText("hello");

MainActivity.java:
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.widget.Button;
import android.widget.ImageButton;
import android.widget.ImageView;
import android.widget.TextView;
import android.widget.Toast;
import android.view.View;
import android.view.View.OnClickListener;
public class MainActivity extends Activity {
Button button1;
TextView textView1;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
button1=(Button)findViewById(R.id.button1);
textView1=(TextView)findViewById(R.id.textView1);
button1.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
textView1.setText("TextView displayed Successfully");
}
});
}
}
activity_main.xml:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<Button
android:id="#+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Click here" />
<TextView
android:id="#+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
/>
</LinearLayout>

public void onCreate(Bundle savedInstanceState)
{
setContentView(R.layout.main);
super.onCreate(savedInstanceState);
mybtn = (Button)findViewById(R.id.mybtn);
txtView=(TextView)findViewById(R.id.txtView);
mybtn .setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
txtView.SetText("Your Message");
}
});
}

Check this:
hello.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View paramView) {
text.setText("hello");
}
});

my first application android

hello i try to use simple application in android but i have many problems ;
i need when i click in button text change in "hh";
my main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<Button
android:id="#+id/button1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Button" />
</LinearLayout>
my class
package com.my.Hello;
import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
public class HelloActivity extends Activity{
Button button;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
button = (Button)findViewById(R.id.button1);
button.setText("hh");
button.setOnClickListener(new View.OnClickListener()
{
public void onClick(View v)
{
button.setText("hh");
}
});
setContentView(R.layout.main);
}
}
i have good resultat in UI but when i click in button not thing happen ?

You're setting the text to "hh" in the onCreate() so clicking it would not change it.
Also, you are calling setContentView() twice, so the second time just invalidates everything you've already coded.
Try this:
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
button = (Button) findViewById(R.id.button1);
button.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
button.setText("hh");
}
});
}

Develop Reference

The Android operating system is a mobile operating system that was developed by Google (GOOGL?) to be primarily used for touchscreen devices, cell phones, and tablets.

Resource cannot be resolved or is not a field? - android

Related

Android app is not running on android studio and going to force close

How to debug an Android app that says "unfortunately <app> stopped working"?

How to configure a image pop up for android using eclipce?

displaying a string on the textview when clicking a button in android

my first application android

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