I am trying to create same ImageView 20 times in different locations, I am using this code:
rand = new Random();
ImageView[] imageViewArray = new ImageView[20];
ArrayList<Float> xarray = new ArrayList<>();
ArrayList<Float> yarray = new ArrayList<>();
Display display = getWindowManager().getDefaultDisplay();
Point size = new Point();
display.getSize(size);
layoutwidth = size.x;
layoutheight = size.y;
Toast.makeText(MainActivity.this, " " + layoutwidth, Toast.LENGTH_SHORT).
show();
for (int i = 0; i < 20; i++) {
imageViewArray[i] = new ImageView(this);
imageViewArray[i].setTag(i);
imageViewArray[i].setImageResource(R.mipmap.enemy);
randx = rand.nextInt(layoutwidth + 1);
randy = rand.nextInt(layoutheight + 1);
imageViewArray[i].setX(randx);
imageViewArray[i].setY(randy);
xarray.add(imageViewArray[i].getX());
yarray.add(imageViewArray[i].getY());
rlt.addView(imageViewArray[i]);
}
Eventually, My app crashes at line rlt.addView(imageViewArray[i]); and says it is a null object, here is my logcat:
09-12 14:15:19.941 20395-20395/? E/AndroidRuntime﹕ FATAL EXCEPTION: main
Process: firstappdevelopment.thatdoskilledme, PID: 20395
java.lang.RuntimeException: Unable to start activity ComponentInfo{firstappdevelopment.thatdoskilledme/firstappdevelopment.thatdoskilledme.MainActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.RelativeLayout.addView(android.view.View)' on a null object reference
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3119)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3218)
at android.app.ActivityThread.access$1000(ActivityThread.java:198)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1676)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:145)
at android.app.ActivityThread.main(ActivityThread.java:6837)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1404)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1199)
at de.robv.android.xposed.XposedBridge.main(XposedBridge.java:115)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.RelativeLayout.addView(android.view.View)' on a null object reference
at firstappdevelopment.thatdoskilledme.MainActivity.onCreate(MainActivity.java:56)
at android.app.Activity.performCreate(Activity.java:6500)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1120)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3072)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3218)
at android.app.ActivityThread.access$1000(ActivityThread.java:198)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1676)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:145)
at android.app.ActivityThread.main(ActivityThread.java:6837)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1404)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1199)
at de.robv.android.xposed.XposedBridge.main(XposedBridge.java:115)
I don't know why it returns null as I created it inside the for statement, can anyone please help me, thank you :)
make sure you declare relative layout properly.
You don't have to take array of image view because all element have same bitmap so define another xml file that contain your image view and each time add that xml layout view to relative layout !
Related
I have an array of pictures which i extract the longitude and latitude details from using exif and put them on a marker on the GPS map. Currently i am using static array which i plan to change to a dynamic array in the near future. The current code crashes my app everytime i try to set my marker, i have no idea whats wrong.
public void setMarker() {
double latitude, longitude;
String[] filepath = {"/storage/emulated/0/Pictures/CapturyGallery/CapImage1451887532716.jpg", "/storage/emulated/0/Pictures/CapturyGallery/CapImage1452411474153.jpg"};
ExifInterface intf = null;
for (int y = 0; y < filepath.length; y++) {
try {
intf = new ExifInterface(filepath[y]);
} catch (IOException e) {
e.printStackTrace();
}
if (intf != null) {
latitude = Double.parseDouble(intf.getAttribute(ExifInterface.TAG_GPS_LATITUDE));
longitude = Double.parseDouble(intf.getAttribute(ExifInterface.TAG_GPS_LONGITUDE));
LatLng latLngCurrent = new LatLng(latitude, longitude);
MarkerOptions options = new MarkerOptions()
.position(latLngCurrent)
.title("test");
mMap.addMarker(options);
}
}
}
LOGCAT
`
01-11 15:19:30.251 32226-32226/com.sp.fyp.captury E/AndroidRuntime﹕ FATAL EXCEPTION: main
Process: com.sp.fyp.captury, PID: 32226
java.lang.IllegalStateException: Could not execute method of the activity
at android.view.View$1.onClick(View.java:4298)
at android.view.View.performClick(View.java:5254)
at android.view.View$PerformClick.run(View.java:21179)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:145)
at android.app.ActivityThread.main(ActivityThread.java:6843)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1404)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1199)
Caused by: java.lang.reflect.InvocationTargetException
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at android.view.View$1.onClick(View.java:4293)
at android.view.View.performClick(View.java:5254)
at android.view.View$PerformClick.run(View.java:21179)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:145)
at android.app.ActivityThread.main(ActivityThread.java:6843)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1404)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1199)
Caused by: java.lang.NumberFormatException: Invalid double: "1/1,18/1,30/1"
at java.lang.StringToReal.invalidReal(StringToReal.java:63)
at java.lang.StringToReal.initialParse(StringToReal.java:164)
at java.lang.StringToReal.parseDouble(StringToReal.java:282)
at java.lang.Double.parseDouble(Double.java:301)
at com.sp.fyp.captury.GPS.setMarker(GPS.java:181)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at android.view.View$1.onClick(View.java:4293)
at android.view.View.performClick(View.java:5254)
at android.view.View$PerformClick.run(View.java:21179)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:145)
at android.app.ActivityThread.main(ActivityThread.java:6843)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1404)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1199)`
According to the Standard Exif Tags (as defined in the Exif 2.3 standard)
The latitude/longitude is expressed as three RATIONAL values giving
the degrees, minutes, and seconds, respectively. When degrees, minutes
and seconds are expressed, the format is dd/1,mm/1,ss/1. When degrees
and minutes are used and, for example, fractions of minutes are given
up to two decimal places, the format is dd/1,mmmm/100,0/1
Thus, when you get the latitude and logitude from the ExifInterface, you are getting values like 1/1,18/1,30/1. Of course this String values cannot be converted to double using Double.parseDouble and throw a NumberFormatException.
You can take a look at How do I convert Exif long/lat to real values? to find a converter.
i have a problem with getActionBar(), this problem happens when i'm trying to change view of action bar , i'm getting this error:
java.lang.RuntimeException: Unable to start activity ComponentInfo{h.ui01/h.ui01.MainActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.app.ActionBar.setNavigationMode(int)' on a null object reference
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3119)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3218)
at android.app.ActivityThread.access$1000(ActivityThread.java:198)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1676)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:145)
at android.app.ActivityThread.main(ActivityThread.java:6837)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1404)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1199)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.app.ActionBar.setNavigationMode(int)' on a null object reference
at h.ui01.MainActivity.onCreate(MainActivity.java:28)
at android.app.Activity.performCreate(Activity.java:6500)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1120)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3072)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3218)
at android.app.ActivityThread.access$1000(ActivityThread.java:198)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1676)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:145)
at android.app.ActivityThread.main(ActivityThread.java:6837)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1404)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1199)
My code is here :
public class MainActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
final ActionBar actionBar = getSupportActionBar();
actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_STANDARD);
LayoutInflater inflater = (LayoutInflater) this.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View view = inflater.inflate(R.layout.action_bar, null);
actionBar.setCustomView(view, new ActionBar.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT));
actionBar.setDisplayOptions(ActionBar.DISPLAY_SHOW_CUSTOM);
}
}
even when i try to hide action bar or change color of the action bar , i saw similar error.
I was trying to make a ListView of reminder notes. But when I try to save it and display it in a ListView, app crashes with this error/exception. saveNote method is called when you press save button. Any help is appreciated.
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
switch(id) {
case R.id.add_reminder : {
et = (EditText)findViewById(R.id.new_note);
et.setVisibility(View.VISIBLE);
note = et.getText().toString();
i++;
Button save_button = (Button) findViewById(R.id.button_save);
save_button.setVisibility(View.VISIBLE);
}
default : return super.onOptionsItemSelected(item);
}
}
public void saveNote(View view) {
String[] notes = new String[20];
notes[i] = note;
listView = (ListView) findViewById(R.id.list);
ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, android.R.id.text1,notes);
listView.setAdapter(adapter);
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
//Clicked item index
int itemPosition = position;
//Clicked item value
String itemNote = (String) listView.getItemAtPosition(position);
//Alert
Toast.makeText(getApplicationContext(), "Position :" + itemPosition + " ListItem : " + itemNote, Toast.LENGTH_LONG).show();
}
});
Logcat
java.lang.IllegalStateException: Could not execute method of the activity
at android.view.View$1.onClick(View.java:4020)
at android.view.View.performClick(View.java:4780)
at android.view.View$PerformClick.run(View.java:19866)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5257)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698)
Caused by: java.lang.reflect.InvocationTargetException
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at android.view.View$1.onClick(View.java:4015)
at android.view.View.performClick(View.java:4780)
at android.view.View$PerformClick.run(View.java:19866)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5257)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.ListView.setAdapter(android.widget.ListAdapter)' on a null object reference
at com.cokosofts.pramith.reminder.MainActivity.saveNote(MainActivity.java:69)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at android.view.View$1.onClick(View.java:4015)
at android.view.View.performClick(View.java:4780)
at android.view.View$PerformClick.run(View.java:19866)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5257)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698)
The main cause which I found from the Logs is ListView is null. Please check one more time if the listView is empty or not? Also what is notes[i] = note ??
I think in each Save button click you are finding ListView and the setting Adapter each time. This is not a good approach from my point of view. You should set the adapter very first time and next time just update your adapter data and call notifyDataSetChanged();
Debug and find out why your ListView was not found on your layout (was null).
Problem is with following line:
listView = (ListView) findViewById(R.id.list);
Please check whether your xml has ListView widget with id as 'list' .
If id is different in XML it will result in a NULL object reference. When you call
listView.setAdapter(adapter)
It will give a NULL pointer exception.
when I tried to add some values to my List inside my onResume() method i got this error:
java.lang.RuntimeException: Unable to resume activity {.../...MainActivity}: java.lang.UnsupportedOperationException
at android.app.ActivityThread.performResumeActivity(ActivityThread.java:3096)
at android.app.ActivityThread.handleResumeActivity(ActivityThread.java:3127)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2482)
at android.app.ActivityThread.-wrap11(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1345)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:5415)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:725)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:615)
Caused by: java.lang.UnsupportedOperationException
at java.util.AbstractList.add(AbstractList.java:404)
at java.util.AbstractList.add(AbstractList.java:425)
at de.toeducate.tograde.MainActivity.onResume(MainActivity.java:151)
at android.app.Instrumentation.callActivityOnResume(Instrumentation.java:1258)
at android.app.Activity.performResume(Activity.java:6237) at android.app.ActivityThread.performResumeActivity(ActivityThread.java:3085)
at android.app.ActivityThread.handleResumeActivity(ActivityThread.java:3127)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2482)
at android.app.ActivityThread.-wrap11(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1345)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:5415)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:725)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:615)
and here is the code I wrote:
List<Integer> marks = Collections.emptyList();
for (int i = 0; i < dataBase.getDataMark().size(); i++) {
marks.add(dataBase.getDataMark().get(i).getValue());
}
What does this mean?
Collections.emptyList(); returns a List that you cannot add to (hence the UnsupportedOperationException).
Use
List<Integer> marks = new ArrayList<Integer>();
instead.
Collections.emptyList() returns an instance of AbstractList. This is meant by the line
Caused by: java.lang.UnsupportedOperationException
at java.util.AbstractList.add(AbstractList.java:404)
in your exception's stack trace. This said you cannot call add on your marks list as add is not implemented.
Instead instantiate marks with a class that allows for adding elements, such as ArrayList:
List<Integer> marks = new ArrayList<Integer>();
Besides ArrayList, LinkedList is another implementation of AbstractList that supports adding elements. Most typically programmers use an ArrayList.
I have an imageview which has an image loaded in it. This way
// create bitmap from resource
Bitmap bm = BitmapFactory.decodeResource(getResources(),
R.drawable.profile_blank_xlarge);
// set circle bitmap
ImageView mImage = (ImageView) layout.findViewById(R.id.image);
mImage.setImageBitmap(getCircleBitmap(bm));
I want to be able to find out the name of the image in the ImageView once the application is run.
I tried doing mImage.getTag() to get the name of the image in the ImageView but it crashes my app.
What is the correct way to get the name of the image in a ImageView
Crash Details
--------- beginning of crash
07-02 13:11:37.259 2096-2096/com.example.kmi_dev.fbloginsample E/AndroidRuntime﹕ FATAL EXCEPTION: main
Process: com.example.kmi_dev.fbloginsample, PID: 2096
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.kmi_dev.fbloginsample/com.example.kmi_dev.fbloginsample.MyActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String java.lang.Object.toString()' on a null object reference
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2325)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2390)
at android.app.ActivityThread.access$800(ActivityThread.java:151)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1303)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5257)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String java.lang.Object.toString()' on a null object reference
at com.example.kmi_dev.fbloginsample.MyAccount.onCreateView(MyAccount.java:115)
at android.app.Fragment.performCreateView(Fragment.java:2053)
at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:894)
at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:1067)
at android.app.BackStackRecord.run(BackStackRecord.java:834)
at android.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1452)
at android.app.Activity.performStart(Activity.java:6005)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2288)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2390)
at android.app.ActivityThread.access$800(ActivityThread.java:151)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1303)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5257)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698)