Hi guys i am new on android developing and i am trying to rotate an imageview.
The problem comes when (obviously) i push the button and the app close itself
Code java:
package comad.exampleaaaa.vittoriodaadntico.bottiglia3;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.animation.Animation;
import android.view.animation.LinearInterpolator;
import android.view.animation.RotateAnimation;
import android.widget.Button;
import android.widget.ImageView;
public class MainActivity6 extends AppCompatActivity {
public ImageView bottiglia;
public Button gira;
#Override
protected void onCreate(Bundle savedInstanceState) {
gira=(Button)findViewById(R.id.btn_roll);
bottiglia=(ImageView)findViewById(R.id.bottiglia);
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main6);
}
public void rollOnClick(View v){
RotateAnimation anim=new RotateAnimation(0,360,20,20,20,20);
anim.setInterpolator(new LinearInterpolator());
anim.setRepeatCount(Animation.INFINITE);
anim.setDuration(700);
bottiglia.startAnimation(anim);
}
#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_activity6, 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);
}
}
error log :
http://imgur.com/H2Phsvf
You call methods in wrong order:
#Override
protected void onCreate(Bundle savedInstanceState) {
gira=(Button)findViewById(R.id.btn_roll); // This
bottiglia=(ImageView)findViewById(R.id.bottiglia); // And this
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main6); // Should come after this
}
Here you search for views before you set content view. You should set your view, and only then search for widgets. Otherwise there is no view in which your widgets could be found, so both gira and bottiglia are nulls:
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main6);
gira=(Button)findViewById(R.id.btn_roll);
bottiglia=(ImageView)findViewById(R.id.bottiglia);
}
Related
I'm trying to create an animation for an ImageView which shows like picture below (collected on Stackoverflow).
I want to do this because I want it shows when my location is locating. I've tried to find keywords but i couldn't found anything. Thanks.
You can use Wavedrawable Library.
it is available in GitHub with sample projects.
https://github.com/Alexrs95/WaveDrawable
compile 'me.alexrs:wave-drawable:1.0.0'
import android.app.Activity;
import android.graphics.Color;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.animation.Interpolator;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.ImageView;
import android.widget.Spinner;
import me.alexrs.wavedrawable.WaveDrawable;
public class MainActivity extends Activity {
private WaveDrawable waveDrawable;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ImageView imageView = (ImageView) findViewById(R.id.image);
waveDrawable = new WaveDrawable(Color.parseColor("#8e44ad"), 500);
imageView.setBackgroundDrawable(waveDrawable);
interpolator = new LinearInterpolator();
waveDrawable.setWaveInterpolator(interpolator);
waveDrawable.startAnimation();
}
#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);
}
}
WelcomeActivity:
package com.emdad.androidapp;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.Window;
import android.view.WindowManager;
public class WelcomeActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
findViewById(R.id.androidButton).setOnClickListener(new OnClickListener() {
#Override
public void onClick(View arg0) {
Intent intent=new Intent(WelcomeActivity.this, GameActivity.class);
startActivity(intent);
}
});
setContentView(R.layout.activity_welcome);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.welcome, 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);
}
}
GameActivity:
package com.emdad.androidapp;
import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
public class GameActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_game);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.game, 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);
}
}
When it was run in Android Virtual Device, it replied "Unfortunately, it has stopped." What is the problem?
You should move
setContentView(R.layout.activity_welcome);
before
findViewById(R.id.androidButton).setOnClickListener(new OnClickListener() {
Corrected:
setContentView(R.layout.activity_welcome);
findViewById(R.id.androidButton).setOnClickListener(new OnClickListener() {
#Override
public void onClick(View arg0) {
Intent intent=new Intent(WelcomeActivity.this, GameActivity.class);
startActivity(intent);
}
});
1 it showing a error package android.veiw does not exist in my android studio
2 when i add a buuton and use onClick
package com.example.batman.buttoncheck;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.Menu;
import android.veiw.Veiw;
import android.view.MenuItem;
public class Button_MainActivity extends ActionBarActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_button__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.menu_button__main, menu);
return true;
}
public void buttononClick(Veiw v){
//do nothing
}
#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);
}
}
Typo.
Change
import android.veiw.Veiw
to
import android.view.View
And similarly
public void buttononClick(Veiw v)
to
public void buttononClick(View v)
I have 2 activities. One is the main activity. One is the Preference activity. I'm trying to change the background color of the activity based on the color selected in a RadioGroup in the Preference activity.
This is the class file for the main activity.
package com.example.mycsimodules;
import android.support.v7.app.ActionBarActivity;
import android.content.Intent;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.ArrayAdapter;
public class ModList extends ActionBarActivity {
SharedPreferences savedData;
private String[] moduleArray = { "COMP 41600", "COMP 41620", "COMP 47330","COMP 30160", "COMP 30500", "COMP 40725", "COMP 41100", "COMP 41110" };
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_mod_list);
savedData=getSharedPreferences("MyPrefs",0);
String colorMine=savedData.getString("color", "deflt");
TextView head=(TextView) findViewById(R.id.mymodlist);
head.setText(colorMine);
ArrayAdapter<String> moduleAdapter = new ArrayAdapter<String>(this, R.layout.activity_list_view, R.id.list1, moduleArray);
final ListView list = (ListView) findViewById(R.id.mod_list);
list.setAdapter(moduleAdapter);
}
});
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.mod_list, 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) {
Intent i=new Intent(this, Preferences.class);
startActivity(i);
return true;
}
return super.onOptionsItemSelected(item);
}
This is the class file for the Preference class.
package com.example.mycsimodules;
import android.support.v7.app.ActionBarActivity;
import android.annotation.SuppressLint;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.RadioButton;
import android.widget.RadioGroup;
import android.widget.TextView;
public class Preferences extends ActionBarActivity implements OnClickListener{
RadioGroup colorList;
Button saveButton;
SharedPreferences savedData;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_preferences);
colorList=(RadioGroup) findViewById(R.id.colorRadioGroup);
saveButton=(Button) findViewById(R.id.bSave);
saveButton.setOnClickListener(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.preferences, 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);
}
#SuppressLint("NewApi") #Override
public void onClick(View v) {
// TODO Auto-generated method stub
if(v==saveButton){
RadioButton myColor=(RadioButton) findViewById(colorList.getCheckedRadioButtonId());
String colorSelected=myColor.getText().toString();
TextView label=(TextView) findViewById(R.id.the_color_is);
label.setText(colorSelected);
savedData=getSharedPreferences("MyPref", 0);
SharedPreferences.Editor editor=savedData.edit();
editor.putString("color", colorSelected);
editor.apply();
editor.commit();
}
}
}
I haven't actually done the background color part. I'm just trying to display the value in a TextView currently. But it shows only the default value all the time. What I'm trying to do is.
Click on Settings.
Click on RadioButton for color desired.
Click on Save button.
Click on back key to return to main activity.
I'm pretty new to this and might be doing something wrong. But I just can't figure out what it is.
savedData=getSharedPreferences("MyPrefs",0);
it's diferent from
savedData=getSharedPreferences("MyPref", 0);
Use the same file when you open your SharedPreferences
How can i switch activity using Button? this is my problem:
package net.example.finals;
import android.support.v7.app.ActionBarActivity;
import android.support.v7.app.ActionBar;
import android.support.v4.app.Fragment;
import android.content.Intent;
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.AdapterView;
import android.widget.Button;
import android.os.Build;
public class MainActivity extends ActionBarActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
if (savedInstanceState == null) {
getSupportFragmentManager().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 implements OnClickListener {
Button bq;
Button bw;
Button be;
Button br;
Button bt;
Button by;
Button bu;
public PlaceholderFragment() {
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_second,
container, false);
bq=(Button)rootView.findViewById(R.id.btn1);
bq.setOnClickListener(this);
bw=(Button)rootView.findViewById(R.id.btn2);
bw.setOnClickListener(this);
be=(Button)rootView.findViewById(R.id.btn3);
be.setOnClickListener(this);
br=(Button)rootView.findViewById(R.id.btn4);
br.setOnClickListener(this);
bt=(Button)rootView.findViewById(R.id.btn5);
bt.setOnClickListener(this);
by=(Button)rootView.findViewById(R.id.btn6);
by.setOnClickListener(this);
bu=(Button)rootView.findViewById(R.id.btn7);
bu.setOnClickListener(this);
return rootView;
}
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
//i dont know what to put here
case R.id.btn1:
if(bq.callOnClick()==true){
Intent myOwnIntent = new Intent(getActivity(), Second.class);
startActivity(myOwnIntent);
}
break;
}
}
}
Why did you use "if(bq.callOnClick()==true)" this?
Android use a lots of java code, first you need to learn java properly.
AND Google too
#Override
public void onClick(View v) {
int id = v.getId();
switch(id){
case R.id.btn1:
Intent myOwnIntent = new Intent(YourActivityName.this, Second.class);
startActivity(myOwnIntent);
break;
}
}
Try this one.
How to start new activity on button click
Start another activity by clicking a button
Android eclipse how to start a new activity on button click