Getting "Unfortunately, app has stopped" while executing

Getting "Unfortunately, app has stopped" while executing - android

I am learning Android dev in Android Studio.
I created an app which displays some text on fling and some other on click of a button.
But its showing "Unfortunately app has stopped"
Also, I have only one activity. So, its not possible that I forgot to show it in AndroidManifest.xml
here is my java code :
package com.example.mahe.pro2;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.TextView;
import android.widget.Button;
import android.view.GestureDetector;
import android.view.MotionEvent;
import android.view.View;
import android.support.v4.view.GestureDetectorCompat;
public class MainActivity extends AppCompatActivity implements GestureDetector.OnGestureListener {
private TextView tv = (TextView) findViewById(R.id.t);
private GestureDetectorCompat gd;
private Button bt = (Button) findViewById(R.id.b);
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
this.gd = new GestureDetectorCompat(this,this);
bt.setOnClickListener(
new Button.OnClickListener() {
public void onClick(View v) {
tv.setText("That was a Click!");
}
}
);
}
#Override
public void onLongPress(MotionEvent motionEvent) {
}
#Override
public boolean onSingleTapUp(MotionEvent motionEvent) {
return false;
}
#Override
public boolean onScroll(MotionEvent motionEvent, MotionEvent motionEvent1, float v, float v1) {
return false;
}
#Override
public void onShowPress(MotionEvent motionEvent) {
}
#Override
public boolean onDown(MotionEvent motionEvent) {
return false;
}
#Override
public boolean onFling(MotionEvent motionEvent, MotionEvent motionEvent1, float v, float v1) {
tv.setText("That was a Swipe, Baby");
return true;
}
#Override
public boolean onTouchEvent(MotionEvent event) {
this.gd.onTouchEvent(event);
return super.onTouchEvent(event);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}
Here's my xml code :
<RelativeLayout 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:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
android:paddingBottom="#dimen/activity_vertical_margin" tools:context=".MainActivity">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:text="YO!"
android:id="#+id/t"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:layout_marginTop="62dp" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Click"
android:id="#+id/b"
android:layout_below="#+id/t"
android:layout_centerHorizontal="true"
android:layout_marginTop="164dp" />

Just move
TextView tv = (TextView) findViewById(R.id.t);
Button bt = (Button) findViewById(R.id.b);
under onCreate(...) after setContentView(R.layout.activity_main);

as #M D said
you must first create your view and setview to can get R.id.b
but if you want to declare them as a global variable , use
private TextView tv;
private Button bt
above the onCreate Method , then in onCreate method and under
setContentView(R.layout.activity_main);
use
tv = (TextView) findViewById(R.id.t);
bt = (Button) findViewById(R.id.b);

Related

Youtubeapi error in xml file

I am new in Android Trying to run YouTube Video. When I add YouTubePlayerView in XML file it gives me the error:
The following classes could not be instantiated: - com.google.android.youtube.player.YouTubePlayerView
because of-
"java.lang.IllegalStateException: A YouTubePlayerView can only be created with an Activity which extends YouTubeBaseActivity as its context."
My XML file:
<RelativeLayout 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: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.youtubeapi.MainActivity" >
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/hello_world" />
<com.google.android.youtube.player.YouTubePlayerView
android:id="#+id/youtube_view"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
</RelativeLayout>
My Main Activity class:
package com.example.youtubeapi;
import com.google.android.youtube.player.YouTubeBaseActivity;
import com.google.android.youtube.player.YouTubeInitializationResult;
import com.google.android.youtube.player.YouTubePlayer;
import com.google.android.youtube.player.YouTubePlayer.Provider;
import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
public class MainActivity extends YouTubeBaseActivity implements YouTubePlayer.OnInitializedListener {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
#Override
public void onInitializationFailure(Provider arg0,
YouTubeInitializationResult arg1) {
// TODO Auto-generated method stub
}
#Override
public void onInitializationSuccess(Provider arg0, YouTubePlayer arg1,
boolean arg2) {
// TODO Auto-generated method stub
}
}
so I have done it and my activity now extends YouTubeBaseActivity, but I still got the error for some reason.

Please make sure that you have added "YouTubeAndroidPlayerApi" in libs folder.
Also in build.gradle file add the following line:
compile files('libs/YouTubeAndroidPlayerApi.jar')
activity_main.xml:
<RelativeLayout 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:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
android:paddingBottom="#dimen/activity_vertical_margin" tools:context=".MainActivity">
<TextView android:text="#string/hello_world"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
<com.google.android.youtube.player.YouTubePlayerView
android:id="#+id/youtube_player"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#fff"/>
</RelativeLayout>
MainActivity.java
package com.materialtheme.youtubetestproject;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import com.google.android.youtube.player.YouTubeBaseActivity;
import com.google.android.youtube.player.YouTubeInitializationResult;
import com.google.android.youtube.player.YouTubePlayer;
import com.google.android.youtube.player.YouTubePlayerView;
public class MainActivity extends YouTubeBaseActivity implements YouTubePlayer.OnInitializedListener {
public static final String API_KEY = "AIzaSyDEDrYVfpbqDgD_EsNlsnsFJhcMP8WYjsM";
public static final String videoID = "09R8_2nJtjg";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
YouTubePlayerView youTubePlayerView = (YouTubePlayerView) findViewById(R.id.youtube_player);
youTubePlayerView.initialize(API_KEY, MainActivity.this);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
#Override
public void onInitializationSuccess(YouTubePlayer.Provider provider, YouTubePlayer player, boolean wasRestored) {
/** add listeners to YouTubePlayer instance **/
player.setPlayerStateChangeListener(playerStateChangeListener);
player.setPlaybackEventListener(playbackEventListener);
/** Start buffering **/
if (!wasRestored) {
player.cueVideo(videoID);
}
}
#Override
public void onInitializationFailure(YouTubePlayer.Provider provider, YouTubeInitializationResult youTubeInitializationResult) {
}
private YouTubePlayer.PlaybackEventListener playbackEventListener = new YouTubePlayer.PlaybackEventListener() {
#Override
public void onBuffering(boolean arg0) {
}
#Override
public void onPaused() {
}
#Override
public void onPlaying() {
}
#Override
public void onSeekTo(int arg0) {
}
#Override
public void onStopped() {
}
};
private YouTubePlayer.PlayerStateChangeListener playerStateChangeListener = new YouTubePlayer.PlayerStateChangeListener() {
#Override
public void onAdStarted() {
}
#Override
public void onError(YouTubePlayer.ErrorReason arg0) {
}
#Override
public void onLoaded(String arg0) {
}
#Override
public void onLoading() {
}
#Override
public void onVideoEnded() {
}
#Override
public void onVideoStarted() {
}
};
}

touch event when finger moves to next view

I am dragging my finger and it moves to the next view. Both views implement setOnTouchListener().
How to find out that the finger is now on second view.
ACTION_MOVE is getting returned for first view even though my finger is on second view.
Do I need to implement any other listener?
<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: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.textview.MainActivity" >
<TextView
android:id = "#+id/text1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/hello_world" />
<TextView
android:id = "#+id/text2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="hello_world1" />
<TextView
android:id = "#+id/text3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="hello_world2" />
</LinearLayout>
MainActivity.java:
package com.example.textview;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnTouchListener;
import android.widget.TextView;
public class MainActivity extends ActionBarActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
TextView txt1 = (TextView) findViewById(R.id.text1);
txt1.setOnTouchListener(new OnTouchListener() {
#Override
public boolean onTouch(View v, MotionEvent e) {
TextView txt1 = (TextView) findViewById(v.getId());
Log.d("txt1.getText()",txt1.getText().toString());
return false;
}
});
txt1 = (TextView) findViewById(R.id.text2);
txt1.setOnTouchListener(new OnTouchListener() {
#Override
public boolean onTouch(View v, MotionEvent e) {
TextView txt1 = (TextView) findViewById(v.getId());
Log.d("txt1.getText()",txt1.getText().toString());
return false;
}
});
txt1 = (TextView) findViewById(R.id.text3);
txt1.setOnTouchListener(new OnTouchListener() {
#Override
public boolean onTouch(View v, MotionEvent e) {
TextView txt1 = (TextView) findViewById(v.getId());
Log.d("txt1.getText()",txt1.getText().toString());
return false;
}
});
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}

You can check for the current MotionEvent x and y is in the 2nd view hit rect
Rect viewHitRect = new Rect();
secondView.getHitRect(viewHitRect);
if(viewHitRect.contains((int) motionEvent.getX(), (int) motionEvent.getY())) {//You are in 2nd view}

When finger is coming on textview2, it will get ACTION_HOVER_ENTER and
textview1 will get ACTION_HOVER_EXIT
Check on these parameters, ACTION_MOVE will be given to textview1 as you mentioned but hover parameter clearly decide which textfield is under finger at this time
UPDATE :
If finger is clicked on views then you will get ACTION_DOWN on textview2 and parallely textview1 will get ACTION_UP

How to pass value from a method to another method

import android.support.v4.app.Fragment;
import android.app.Activity;
import android.app.Dialog;
import android.content.Context;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnTouchListener;
import android.view.ViewGroup;
import android.view.View.OnClickListener;
import android.view.inputmethod.InputMethodManager;
import android.widget.*;
import android.widget.NumberPicker.OnValueChangeListener;
public class MainActivity extends Activity implements OnValueChangeListener {
EditText push_ups, sit_ups;
NumberPicker np;
Button calculate;
final Context context = this;
CheckBox checkbox;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
calculate = (Button)findViewById(R.id.calculate);
push_ups = (EditText)findViewById(R.id.pushups);
sit_ups = (EditText)findViewById(R.id.situps);
np = (NumberPicker)findViewById(R.id.np1);
checkbox = (CheckBox)findViewById(R.id.checkbox);
String[] values = {"some array"};
np.setMaxValue(values.length-1);
np.setMinValue(0);
np.setDisplayedValues(values);
np.setWrapSelectorWheel(false);
//calculateButton runs when I click the "calculate" Button
calculateButton();
LinearLayout layout = (LinearLayout)findViewById(R.id.linearLayout1);
layout.setOnTouchListener(new OnTouchListener() {
#Override
public boolean onTouch(View v, MotionEvent event) {
hideKeyboard();
return false;
}
});
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
/**
* A placeholder fragment containing a simple view.
*/
public static class PlaceholderFragment extends Fragment {
public PlaceholderFragment() {
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_main, container,
false);
return rootView;
}
}
#Override
public void onValueChange(NumberPicker picker, int oldVal, int newVal) {
}
private void hideKeyboard() {
InputMethodManager imm = (InputMethodManager)context.getSystemService(Context.INPUT_METHOD_SERVICE);
imm.hideSoftInputFromWindow(push_ups.getWindowToken(), 0);
}
public int calculatePushups() {
int pushupScore = 0;
int ageGroup = Integer.parseInt(null, np.getValue());
int pushupReps = Integer.parseInt(push_ups.getText().toString());
final int [][] pushupTable = {"some 2D array"};
if (pushupReps<= 60) {
pushupScore = pushupTable[pushupReps][ageGroup];
} else {
pushupScore = 60;
}
return pushupScore;
}
public int calculateSitups() {
final int [][] situpTable = {"some 2D array"};
return 0;
}
private void normalRun() {
}
private void specialRun() {
}
private void calculateRun() {
if (checkbox.isChecked()) {
specialRun();
}
else {
normalRun();
}
}
private void calculateScore() {
calculatePushups();
calculateSitups();
calculateRun();
}
public void calculateButton() {
final TextView pus = (TextView)findViewById(R.id.pushup_score);
calculate.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
// custom dialog
final Dialog dialog = new Dialog(context);
dialog.setContentView(R.layout.dialog_custom);
dialog.setTitle("Score");
I am trying to set the TextView to display the pushupScore here but it seems I am trying to pass a result from another method to this. I have no idea how to get it around still new with android,
//pus.setText(pushupScore);
pus.setText(String.valueOf(calculatePushups()));
Button dialogButton = (Button) dialog.findViewById(R.id.dialog_ok);
// if button is clicked, close the custom dialog
dialogButton.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
dialog.dismiss();
}
});
dialog.show();
}
});
}
}
Here's my dialog XML code:
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content" >
<TextView
android:id="#+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:lineSpacingExtra="5dp"
android:text="Push-ups: "
android:textAppearance="?android:attr/textAppearanceMedium" />
<TextView
android:id="#+id/pushup_score"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="4.97"
android:textAppearance="?android:attr/textAppearanceMedium" />
</LinearLayout>
<TextView
android:id="#+id/textView2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:lineSpacingExtra="5dp"
android:text="Sit-ups: "
android:textAppearance="?android:attr/textAppearanceMedium" />
<TextView
android:id="#+id/textView3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:lineSpacingExtra="5dp"
android:text="2.4km Run: "
android:textAppearance="?android:attr/textAppearanceMedium" />
<TextView
android:id="#+id/textView4"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:lineSpacingExtra="5dp"
android:text="Award: "
android:textAppearance="?android:attr/textAppearanceLarge" />
<Button
android:id="#+id/dialog_ok"
style="#style/AppTheme"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal"
android:lineSpacingExtra="5dp"
android:text="Ok" />
</LinearLayout>

you are returning the pushupScore in calculatePushups so just write:
pus.setText(String.valueOf(calculatePushups()));
And btw this is not a android mechanism, this is simple java return usage:
http://docs.oracle.com/javase/tutorial/java/javaOO/returnvalue.html

You left out quite a bit of your code so I'm not sure where your problem is, but if you could follow these steps and let me know if you're getting any errors etc? Anyway, here is what you need to have:
Make sure your Activity implements OnClickListener:
public class MainActivity extends Activity implements OnClickListener, OnValueChangeListener {
//...
}
Within the activity's overridden onCreate() method, register the activity as the handler:
calculate = (Button)v.findViewById(R.id.dialog_ok);
calculate.setOnClickListener(this);
Within MainActivity, have the handler like so:
public void onClick(View v){
switch(v.getId(){
case R.id.dialog_ok:
push_ups.setText("" + calculatePushups());
break;
}
// ...
}
Perhaps you should change your EditText into a TextView, the EditText isn't necessary and might be causing problems?
Is this what you were after?

Display touch coordinates on screen

My objective is to have the user touch anywhere on the screen, and then to have the touch coordinates appear in a textview on the screen.
This is what I have so far.
activity_main.xml:
<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"
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=".MainActivity" >
<TextView
android:id="#+id/touchView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="TextView" />
<TextView
android:id="#+id/textView1"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="To be filled" />
</LinearLayout>
Main Activity.java:
package com.example.myfirstapp;
import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MotionEvent;
import android.view.View;
import android.widget.TextView;
public class MainActivity extends Activity {
public final static String EXTRA_MESSAGE = "com.example.MyFirstApp.MESSAGE";
#Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
final TextView textView = (TextView)findViewById(R.id.textView1);
// this is the view on which you will listen for touch events
final View touchView = findViewById(R.id.touchView);
touchView.setOnTouchListener(new View.OnTouchListener() {
#Override
public boolean onTouch(View v, MotionEvent event) {
textView.setText("Touch coordinates : " +
String.valueOf(event.getX()) + "x" + String.valueOf(event.getY()));
return true;
}
});
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}
SOLVED My first problem is that on MainActivity.java, there is an error on line 18, in the code setContentView(R.layout.main);. Researching online, it looks like the way to fix this error is to change import android.R; to import your.application.packagename.R;. However, I do not have import android.R; in my .java file. Does anyone know how to fix this error?
EDIT Second, the textView only displays the touch coordinates when the first textview is clicked, it does not display the touch coordinates of a touchpoint anywhere on the screen (it only displays the touch coordinates of a touch point on the first text view). How can I change this so that the touch coordinates of anywhere on the screen are displayed?
Another Edit One idea I had for the second problem was giving the LinearLayout I had an id, such as android:id="#+id/touchLayout". I was then planning on modifying the .java file as such:
public class MainActivity extends Activity {
public final static String EXTRA_MESSAGE = "com.example.MyFirstApp.MESSAGE";
#Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
final TextView textView = (TextView)findViewById(R.id.textView1);
// this is the view on which you will listen for touch events
final View touchLayout = findViewById(R.id.touchLayout);
touchLayout.setOnTouchListener(new View.OnTouchListener() {
#Override
public boolean onTouch(View v, MotionEvent event) {
textView.setText("Touch coordinates : " +
String.valueOf(event.getX()) + "x" + String.valueOf(event.getY()));
return true;
}
});
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}

Change the following:
setContentView(R.layout.activity_main);

Yup, the answer I had in the second edit was correct. I simply replaced gave the LinearLayout an id, and replaced the touchView id with the LinearLayout id

Problems with the event treatment of a Button

Something very weird is happening in my program. I try to use the button with the first program below (using an emulator) and the program did not even open. So I changed to the second version, using the android:OnClick, and it did not work either (the program opened, but in the click it crashed). Then I tried the third program, using android:onCLick and the instanciation of the EditText in the treatment function, and the program worked.
Can someone explain to me why the first two programs did not worked?
Edit: I noticed now that LogCat is pointing to the following error: error opening trace file: No such file oor directory (2), what is that? Can it have any relation to this error?
And if I comment the definition of the onClickListener to b1 the program do not crash anymore.
First code:
package app.projetnf33;
import android.app.Activity;
import android.app.Fragment;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Spinner;
public class MainActivity extends Activity implements OnClickListener{
String[] names;
EditText status;
EditText par1;
EditText par2;
EditText par3;
Button b1;
Button b2;
Button b3;
Button b4;
Spinner spin;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
status = (EditText) findViewById(R.id.text);
b1 = (Button) findViewById(R.id.b1);
b1.setOnClickListener(new OnClickListener(){
#Override
public void onClick(View v) {
status.setText("Connect");
}
});
if (savedInstanceState == null) {
getFragmentManager().beginTransaction()
.add(R.id.container, new PlaceholderFragment()).commit();
}
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
/**
* A placeholder fragment containing a simple view.
*/
public static class PlaceholderFragment extends Fragment {
public PlaceholderFragment() {
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_main, container,
false);
return rootView;
}
}
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
}
}
Second code
package app.projetnf33;
import android.app.Activity;
import android.app.Fragment;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Spinner;
public class MainActivity extends Activity implements OnClickListener{
String[] names;
EditText status;
EditText par1;
EditText par2;
EditText par3;
Button b1;
Button b2;
Button b3;
Button b4;
Spinner spin;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
status = (EditText) findViewById(R.id.text);
if (savedInstanceState == null) {
getFragmentManager().beginTransaction()
.add(R.id.container, new PlaceholderFragment()).commit();
}
}
public void treatment_connect(View v){
status.setText("Connect");
}
public void treatment_persons(View v){
status.setText("Persons");
}
public void treatment_lecture(View v){
status.setText("Lecture");
}
public void treatment_execute(View v){
status.setText("Execute");
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
/**
* A placeholder fragment containing a simple view.
*/
public static class PlaceholderFragment extends Fragment {
public PlaceholderFragment() {
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_main, container,
false);
return rootView;
}
}
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
}
}
Third code (which worked):
package app.projetnf33;
import android.app.Activity;
import android.app.Fragment;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Spinner;
public class MainActivity extends Activity implements OnClickListener{
String[] names;
EditText status;
EditText par1;
EditText par2;
EditText par3;
Button b1;
Button b2;
Button b3;
Button b4;
Spinner spin;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
if (savedInstanceState == null) {
getFragmentManager().beginTransaction()
.add(R.id.container, new PlaceholderFragment()).commit();
}
}
public void treatment_connect(View v){
status = (EditText) findViewById(R.id.text);
status.setText("Connect");
}
public void treatment_persons(View v){
status.setText("Persons");
}
public void treatment_lecture(View v){
status.setText("Lecture");
}
public void treatment_execute(View v){
status.setText("Execute");
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
/**
* A placeholder fragment containing a simple view.
*/
public static class PlaceholderFragment extends Fragment {
public PlaceholderFragment() {
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_main, container,
false);
return rootView;
}
}
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
}
}
Fragment_layout:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal" >
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/tex_status" />
<EditText
android:id="#+id/text"
android:inputType="text"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
</LinearLayout>
<Spinner
android:id="#+id/spinner"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal" >
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/par1" />
<EditText
android:id="#+id/par1"
android:inputType="text"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal" >
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/par2" />
<EditText
android:id="#+id/par2"
android:inputType="text"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal" >
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/par3" />
<EditText
android:id="#+id/par3"
android:inputType="text"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">
<Button
android:id="#+id/b1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:drawableLeft="#drawable/ic_action_usb"
android:gravity="center_vertical"
android:text="#string/connect"
android:onClick="treatment_connect" />
<Button
android:id="#+id/b2"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:drawableLeft="#drawable/ic_action_computer"
android:gravity="center_vertical"
android:text="#string/read"
android:onClick="treatment_lecture" />
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">
<Button
android:id="#+id/b3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:drawableLeft="#drawable/ic_action_accept"
android:gravity="center_vertical"
android:text="#string/execution"
android:onClick="treatment_execution" />
<Button
android:id="#+id/b4"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:drawableLeft="#drawable/ic_action_warning"
android:gravity="center_vertical"
android:text="#string/disconnect"
android:onClick="treatment_disconnect" />
</LinearLayout>
</LinearLayout>

In the first and seconds layout you tried to call
status = (EditText) findViewById(R.id.text);
b1 = (Button) findViewById(R.id.b1);
before
getFragmentManager().beginTransaction()
.add(R.id.container, new PlaceholderFragment()).commit();
So you tried to reference a Button and EditText contained in the PlaceholderFragment layout before you created the fragment.

The views are in the fragment layout. It only becomes a part of the activity view hierarchy after the fragment transaction has been run. Your pending fragment transaction is executed in activity super.onStart() which comes only after onCreate(). In essence, you're calling findViewById() too early in the first two versions. The third version works because the findViewById() is in the click handler and gets invoked when the fragment is attached to the activity.
Usually you'd call findViewById() to set up listeners and so on at the earliest possibility in fragment onCreateView(), just after the fragment layout is inflated.

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.

Getting "Unfortunately, app has stopped" while executing - android

Just move TextView tv = (TextView) findViewById(R.id.t); Button bt = (Button) findViewById(R.id.b); under onCreate(...) after setContentView(R.layout.activity_main);

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