Develop Reference

How to make visible and invisible an image by clicking a button in android studio?

i have two activities in android studio.act1 with a button and act2 with an imageView. i want to click the button in act1 and make the image in act2 visible. and when i click button for second time, this time make the image invisible and do it again and again and again. how can i do that?

you must create this class;
public class PublicSharedPreferences {
public static void setDefaults(String key, String value, Context context) {
SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(context);
SharedPreferences.Editor editor = prefs.edit();
editor.putString(key, value);
editor.commit();
}
public static String getDefaults(String key, Context context) {
SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(context);
return preferences.getString(key, null);
}
}
and then learn sharedpreferences enter link description here
Activity1;
public class Activity1 extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.layout1);
Button btn1 = (Button) findViewById(R.id.btn1);
btn1.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
String visibilityStr = PublicSharedPreferences.getDefaults("keyVisibility", getApplicationContext());
if (visibilityStr != null) {
if (visibilityStr.equals("0")) {
Toast.makeText(Activity1.this, "it visibled", Toast.LENGTH_SHORT).show();
visibilityStr = "1";
} else {
visibilityStr = "0";
Toast.makeText(Activity1.this, "it invisibled", Toast.LENGTH_SHORT).show();
}
} else {
visibilityStr = "1";
Toast.makeText(Activity1.this, "it visibled", Toast.LENGTH_SHORT).show();
}
PublicSharedPreferences.setDefaults("keyVisibility", visibilityStr, getApplicationContext());
Intent intent = new Intent(Activity1.this, Activity2.class);
Activity1.this.startActivity(intent);
}
});
}
}
Activity2;
public class Activity2 extends AppCompatActivity {
#Override
protected void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.layout2);
ImageView imgView = (ImageView) findViewById(R.id.imgView1);
String visibilityStr = PublicSharedPreferences.getDefaults("keyVisibility", getApplicationContext());
if (visibilityStr.equals("0"))
imgView.setVisibility(View.INVISIBLE);
else
imgView.setVisibility(View.VISIBLE);
}
}
Layout1;
<?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:id="#+id/activity_main"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context="com.c.a.myapplication.Activity1">
<Button
android:id="#+id/btn1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Button1"/>
</LinearLayout>
Layout2;
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<ImageView
android:id="#+id/imgView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#android:drawable/ic_menu_camera"
android:visibility="invisible"/>
</LinearLayout>
Its work.

Try this code....
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ImageView;
public class Sample extends Activity {
ImageView img;
Button btn;
boolean clicked = true;
#Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.sample);
btn = (Button) findViewById(R.id.t1);
btn.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
clicked = true;
Intent intent = new Intent(Sample.this, Dample.class);
intent.putExtra("value", true);
startActivity(intent);
}
});
}
}
//Dample.class In second activity
import android.app.Activity;
import android.graphics.Color;
import android.os.Bundle;
import android.widget.Button;
public class Dample extends Activity {
ImageView img;//use image view
#Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.pimple);
img= (ImageView) findViewById(R.id.t1);
Boolean yourBool = getIntent().getExtras().getBoolean("value");
if (yourBool == true) {
img.setVisibility(View.VISIBLE);///use visibility code for imageview as mentioned above
}
}
}

Onhoverlistener does not work in android studio

I am working in android studio (my phone Android 6.0.1 api 23) on an app, which
should play sound on hover on, stop playing on release. It is not working. Is it because of my hardware? Or my code is wrong?
JAVA:
import android.media.MediaPlayer;
import android.support.annotation.Nullable;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.MotionEvent;
import android.view.View;
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
public class DisplayActivity extends AppCompatActivity {
private MediaPlayer player;
#Override
protected void onResume() {
super.onResume();
player = MediaPlayer.create(this, R.raw.cena);
player.setLooping(true);
}
#Override
protected void onPause() {
super.onPause();
player.release();
player = null;
}
#Override
protected void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
findViewById(R.id.hello).setOnHoverListener(new View.OnHoverListener() {
#Override
public boolean onHover(
View v,
MotionEvent event) {
switch (event.getAction()) {
case MotionEvent.ACTION_HOVER_ENTER:
player.start();
break;
case MotionEvent.ACTION_HOVER_EXIT:
player.pause();
player.seekTo(0);
break;
}
return true;
}
});
}
}
}
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: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.testonhover.MainActivity">
<TextView
android:layout_width="wrap_content"
android:id="#+id/hello"
android:layout_height="wrap_content"
android:text="Hover me!"
android:layout_centerInParent="true"/>
</RelativeLayout>
Could you explain me what should I do to make it work?

Animating android progress bar

I've created ProgressBar in my view, and I would like it to animate when it's value is updated. I'm runnig the code on API 23. How to animate progressBar when It's value is updated?
Here is my activity:
package com.brylkowski.cleaner.cleaner.Errands;
import android.os.AsyncTask;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.support.v7.app.AppCompatActivity;
import android.widget.ProgressBar;
import com.brylkowski.cleaner.cleaner.R;
public class UploadErrandActivity extends AppCompatActivity {
public static final String PROGRESS = "progress";
UploadRequestTask task;
private ProgressBar progressBar;
private Handler handler;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_upload_errand);
progressBar = (ProgressBar) findViewById(R.id.upload_progress);
progressBar.setMax(6);
task = new UploadRequestTask();
handler = new Handler() {
public void handleMessage(android.os.Message msg) {
progressBar.incrementProgressBy(1);
}
};
task.execute();
}
public class UploadRequestTask extends AsyncTask<Void, Void, Boolean> {
UploadRequestTask() {
}
#Override
protected Boolean doInBackground(Void... params) {
for (int i = 1; i <=6; i++){
Message msg = new Message();
Bundle bundle = new Bundle();
bundle.putInt(PROGRESS, i);
msg.setData(bundle);
handler.sendMessage(msg);
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
return true;
}
#Override
protected void onPostExecute(final Boolean success) {
}
#Override
protected void onCancelled() {
}
}
}
and my view:
<?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:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
android:orientation="vertical"
android:gravity="center"
tools:context="com.brylkowski.cleaner.cleaner.Errands.UploadErrandActivity">
<ProgressBar
style="?android:attr/progressBarStyleHorizontal"
android:indeterminate="false"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="#+id/upload_progress"
android:layout_gravity="bottom"
android:longClickable="false"/>
</LinearLayout>

Check this for how to make ProgressBar animation. The only modification you need is instead of applying the animation once when view is initialized, you will need to call
ProgressBarAnimation anim = new ProgressBarAnimation(progressBar, progressBar.getProgress(), to);
anim.setDuration(1000);
progressBar.startAnimation(anim); // play animation immediately
every time you want to update value. Here is documentation for view animation.

Fragment in layout

I'am trying to communicate betwen two fragment extended classes with the help of MainActivity bt always get an error{03-01 14:30:42.675: E/AndroidRuntime(1724): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.myfrag/com.example.myfrag.Tool}: android.view.InflateException: Binary XML file line #8: Error inflating class fragment}
package com.example.myfrag;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.SeekBar;
import android.widget.SeekBar.OnSeekBarChangeListener;
public class ToolBoxFrag extends FragmentActivity implements OnSeekBarChangeListener {
private static int seekvalue = 10;
private static EditText edittext;
ToolbarListener activityCallback;
public interface ToolbarListener {
public void onButtonClick(int position, String text);
}
public void onAttach(Fragment activity) {
super.onAttachFragment(activity);
try {
activityCallback = (ToolbarListener) activity;
} catch (ClassCastException e) {
throw new ClassCastException(activity.toString()
+ " must implement ToolbarListener");
}
}
#Override
public void onProgressChanged(SeekBar seekBar, int progress,
boolean fromUser) {
seekvalue = progress;
}
#Override
public void onStartTrackingTouch(SeekBar arg0) {
// TODO Auto-generated method stub
}
#Override
public void onStopTrackingTouch(SeekBar arg0) {
// TODO Auto-generated method stub
}
#Override
protected void onCreate(Bundle arg0) {
// TODO Auto-generated method stub
super.onCreate(arg0);
setContentView(R.layout.activity_main);
edittext = (EditText)findViewById(R.id.editText1);
final SeekBar seekbar =
(SeekBar) findViewById(R.id.seekBar1);
seekbar.setOnSeekBarChangeListener(this);
final Button button =
(Button) findViewById(R.id.button1);
button.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
buttonClicked(v);
}
});
return ;
}
public void buttonClicked (View view) {
activityCallback.onButtonClick(seekvalue,
edittext.getText().toString());
}
}
TextFragment.java
package com.example.myfrag;
import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
public class TextFragment extends FragmentActivity {
private static TextView textview;
#Override
public void onCreate( Bundle savedInstanceState) {
setContentView(R.layout.main);
textview = (TextView) findViewById(R.id.textView1);
return;
}
public void changeTextProperties(int fontsize, String text)
{
textview.setTextSize(fontsize);
textview.setText(text);
}
}
MainActivity
package com.example.myfrag;
import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
import android.view.Menu;
public class Tool extends FragmentActivity implements ToolBoxFrag.ToolbarListener {
//public TextFragment tf;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.frag2);
}
public void onButtonClick(int fontsize, String text) {
TextFragment tf = new TextFragment();
getSupportFragmentManager().findFragmentById(R.id.main);
tf.changeTextProperties(fontsize, text);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.activity_main,
menu);
return true;
}
}
xml layout
<?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:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".FragmentExampleActivity" >
<fragment
android:id="#+id/activity_main"
android:name="com.example.fragmentexample.ToolbarFragment"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
tools:layout="#layout/activity_main" />
<fragment
android:id="#+id/main"
android:name="com.example.fragmentexample.TextFragment"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_centerVertical="true"
tools:layout="#layout/main" />
</RelativeLayout>

Problem is the class path you have described the fragment name path wrong ..
it should be com.example.myfrag not com.example.fragmentexample
<?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:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".FragmentExampleActivity" >
<fragment
android:id="#+id/activity_main"
android:name="com.example.myfrag.ToolbarFragment"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
tools:layout="#layout/activity_main" />
<fragment
android:id="#+id/main"
android:name="com.example.myfrag.TextFragment"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_centerVertical="true"
tools:layout="#layout/main" />
</RelativeLayout>

Button duplication in android when setting new text

I am working with the android support library, to be able to use fragments from Froyo, and the Sherlock extension, to show an ActionBar.
I have a fragment which shows three textViews and a button, and I want to be able to change the button text dinamically, depending on the content of the Intent. The problem is that when I call button.setText(String text), a second button appears. However, I've called button.getId() when clicking on each of them, and the Id is the same. I don't have a clue of why this is happening, so I'd appreciate some help.
The app is run on a Samsung Galaxy S, with Android 2.3.3. I can't upload a screen capture because I don't have enough reputation yet :(
This is the code:
FRAGMENT
import android.os.Bundle;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import com.actionbarsherlock.app.SherlockFragment;
import com.parse.ParseUser;
import com.tiempoderodar.egdf.EGDF_App;
import com.tiempoderodar.egdf.R;
import com.tiempoderodar.egdf.security.Constants;
/**
* #author Daniel Leal López
*
*/
public class ChapterDetailsFragment extends SherlockFragment{
private Button b;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Log.i("ChapterDetailsFragment", "Created");
}
#Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
ParseUser user = EGDF_App.getUser();
b = (Button) getSherlockActivity().findViewById(R.id.buttonWatchChapter);
if (user != null){
String chapterNumber = "";
Bundle extras = getSherlockActivity().getIntent().getExtras();
String s = extras.getString(Constants.CHAPTER_NUMBER_PARSE);
if((s != null)&&(!s.equals(""))){
// tvNumber.setText(s);
chapterNumber = "Chapter_" + s;
Log.i("Properties", s);
}
String seen = user.getString(chapterNumber);
if((seen != null)&&(!seen.equals(""))&&(seen.equals(Constants.USER_CHAPTER_SEEN))){
b.setText("Second text: "+getString(R.string.watch_chapter_button_text));
Log.i("BUTTON CHANGED", "Text changed to watch");
}
else if((seen != null)&&(!seen.equals(""))&&(seen.equals(Constants.USER_CHAPTER_NOT_SEEN))){
b.setText("Second text: " + getString(R.string.buy_chapter_button_text));
Log.i("BUTTON CHANGED", "Text changed to buy");
}else{
Log.w("DEV ERROR", "Chapter text not obtained");
}
}else{
Log.w("DEV ERROR", "ParseUser is null in EGDF_App!!!");
}
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.chapter_details, container, false);
return view;
}
public void setText(String item) {
getSherlockActivity().getSupportActionBar().setTitle(item);
}
public void setButtonText(String text){
b.setText(text);
}
}
Activity
import android.media.MediaPlayer;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import com.actionbarsherlock.app.SherlockFragmentActivity;
public class ChapterDetailsActivity extends SherlockFragmentActivity {
private Bundle extras;
MediaPlayer mMediaPlayer;
private String chapterNumber;
private boolean isChapterSeen;
// private int duration;
#Override
protected void onCreate(Bundle savedInstanceState) {
setTheme(R.style.Theme_Sherlock_Light_DarkActionBar);
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_chapter_details);
if (savedInstanceState == null) {
// During initial setup, plug in the details fragment.
ChapterDetailsFragment details = new ChapterDetailsFragment();
details.setArguments(getIntent().getExtras());
getSupportFragmentManager().beginTransaction().add(
android.R.id.content, details).commit();
}
}
public void watchChapter(View view){
Log.i("Button", "Watch chapter button PRESSED");
Button b = (Button) view;
Log.d("BUTTON PARENT VIEW", b.getParent().getClass().getName());
Log.d("BUTTON ID", String.valueOf(b.getId()));
String loadChapter = getString(R.string.load_chapter_button_text);
String watchChapter = getString(R.string.watch_chapter_button_text);
String buyChapter = getString(R.string.buy_chapter_button_text);
}
#Override
protected void onPause() {
Log.i("Activity lifecycle", "On pause called");
super.onPause();
}
#Override
protected void onStop() {
Log.i("Activity lifecycle", "On stop called");
super.onStop();
}
#Override
protected void onDestroy() {
Log.i("Activity lifecycle", "On destroy called");
super.onDestroy();
EGDF_App.releaseMediaPlayer();
}
#Override
protected void onResume() {
Log.i("Activity lifecycle", "On resume called");
super.onResume();
}
#Override
protected void onStart() {
Log.i("Activity lifecycle", "On start called");
super.onStart();
}
}
Activity layout
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<fragment
android:id="#+id/chapterDetailsFragment"
android:layout_width="match_parent"
android:layout_height="match_parent"
class="com.tiempoderodar.egdf.content.ChapterDetailsFragment" />
</LinearLayout>
Fragment Layout
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<TextView
android:id="#+id/textViewChapterNumber"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:textSize="30dip" />
<TextView
android:id="#+id/textViewChapterSeason"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:textSize="30dip" />
<TextView
android:id="#+id/textViewChapterSinopsis"
android:layout_width="wrap_content"
android:layout_height="0dip"
android:layout_weight="1"
android:textAppearance="?android:attr/textAppearanceLarge"
android:textSize="30dip" />
<TextView
android:id="#+id/textViewChapterCredits"
android:layout_width="wrap_content"
android:layout_height="0dip"
android:layout_weight="1"
android:textAppearance="?android:attr/textAppearanceLarge"
android:textSize="30dip" />
<Button
android:id="#+id/buttonWatchChapter"
android:layout_height="wrap_content"
android:layout_width="wrap_content"
android:text="#string/watch_chapter_button_text"
android:layout_gravity="center"
android:onClick="watchChapter"/>
</LinearLayout>
Thanks!

I think I might have found the problem. I was calling
b = (Button) getSherlockActivity().findViewById(R.id.button);
but it should be
b = (Button) getView().findViewById(R.id.button);
With that change it works correctly