for my app I need to show a bottom dynamic dialog. I found this solution:
public class bottomBar extends BottomSheetDialogFragment {
public TextView txtLabel;
#SuppressLint("RestrictedApi")
#Override
public void setupDialog(Dialog dialog, int style) {
super.setupDialog(dialog, style);
View contentView = View.inflate(getContext(), R.layout.bottom_bar, null);
dialog.setContentView(contentView);
txtLabel = contentView.findViewById(R.id.txtLabel);
}
wuith bottom_bar.xml like this:
<TextView
android:id="#+id/txtLabel"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="10dp" />
From my MainActivity I call my dialog, and I try to change the txtLabel text this way:
bottomBar bb = new bottomBar();
bb.txtLabel.setText(String.format("mytext %s %s?" , var1, var2));
bb.show(getSupportFragmentManager(), bb.getTag());
When I try to call setText() the app crash:
java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.TextView.setText(java.lang.CharSequence)' on a null objectbb.txtLabel
Can you help me?
note: if I change order I have the same result:
bb.show(getSupportFragmentManager(), bb.getTag());
bb.txtLabel.setText(String.format("mytext %s %s?" , var1, var2));
Your inflated layout is bottom_bar.xml .But your layout name is layout_bar.xml . Check that properly
When you create a new bottomBar() then your attribute public TextView txtLabel; isn't initialized. you should try to show() it first in order to initialized this attribute.
Related
My question is about Android/Java.
I wanna access to other views from my custom view.
My main.xml:
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/mainLinearLayout1">
<org.javaforum.input
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:inputType="textEmailAddress"
required=""
android:hint="Enter your E-Mail"
oninvalid="this.setCustomValidity('SO - Please enter a correct E-Mail!!!')"/>
<org.javaforum.input
android:layout_width="wrap_content"
android:layout_height="wrap_content"
inputType="submit"/>
</LinearLayout>
So when the second "input" view is clicked, I wanna check if there exists an attribute named "required" at the first "input" view.
I tried this in my input.java:
public class input extends TextView{
public input(Context context, AttributeSet attr) {
super(context, attr, getIdentifier(context,attr));
}
#Override
public void onFinishInflate() {
setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
LinearLayout layout = (LinearLayout)findViewById(R.id.mainLinearLayout1);
View v = null;
for(int i=0; i<layout.getChildCount(); i++) {//Error
//Code
}
}
});
}
}
But I get the following error:
java.lang.NullPointerException: Attempt to invoke virtual method 'int android.widget.LinearLayout.getChildCount()' on a null object reference
I don't understand why it's null. It should be already created, right?
So how can I get an LinearLayout reference of my main.xml at my custom view correctly?
To solve the null pointer exception, you will need to search for the other widget in the parent LinearLayout. You can use View.getParent() to identify the parent. Since the view you are looking for is a sibling of the current view, you will find it in the parent.
As for determining if a certain attribute is set, I recommend that the value be captured by its view and a method provided to present that value upon request. Say the value is your "required" value then capture that value locally and provide a method, getRequiredValue(), for instance, to expose it.
You can use
LinearLayout layout = (LinearLayout) getRootView().findViewById(R.id.mainLinearLayout1);
if you only call findViewById inside custom view it only lookup the child view.
This should be called in the Activity's onCreate instead of TextView's onFinishInflate.
First give the submit button an id eg btn_submit, then in onCreate
Button btn_submit = (Button)findViewById(R.id.btn_submit);
btn_submit.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
LinearLayout layout = (LinearLayout)findViewById(R.id.mainLinearLayout1);
View v = null;
for(int i=0; i<layout.getChildCount(); i++) {
//Code
}
}
});
Am trying to use transitions in my App but am facing this problem,
Cannot cast Int to android.view.View
Below is my code:
holder.newsRoot.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent newsIntent = new Intent(NewsAdapter.this.c, NewsDetails.class);
newsIntent.putExtra("newstitle",NewsTitle);
newsIntent.putExtra("detailednews",DetailedNews);
newsIntent.putExtra("newsdate",NewsDate);
newsIntent.putExtra("newsphoto",NewsPhoto);
ActivityOptionsCompat options= ActivityOptionsCompat.makeSceneTransitionAnimation(this,(View)news_image,"image_transit");
c.startActivity(newsIntent,options.toBundle());
}
});
Am trying to integrate it in the Adapter class, but this is the line where the problem is :
`ActivityOptionsCompat options= ActivityOptionsCompat.makeSceneTransitionAnimation(this,(View)news_image,"image_transit")`;
** problem is found on these words**
(View)news_image
My xml code of the ImageView.
<ImageView
android:id="#+id/news_image"
android:layout_width="80dp"
android:transitionName="image_transit"
android:layout_height="80dp"
android:src="#drawable/bbb"/>
PROBLEM: in android, you store the id's of your objects as int, but the int is the view id, not the view itself.
SOLUTION: in order to work with it you need to get the view use findViewById.
ImageView yourImageView = (ImageView) findViewById(R.id.news_image);
In your case you can also use it directly in the problematic method:
ActivityOptionsCompat options=
ActivityOptionsCompat.makeSceneTransitionAnimation(this,
findViewById(R.id.news_image),
"image_transit")`;
Because you placed it in the xml layout:
<ImageView android:id="#+id/news_image"
I have a problem with calling activity from fragment class. More:
XML of adapter's layout:
<TextView
style="#style/LiHeadLogin"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:foreground="?android:attr/selectableItemBackground"
android:clickable="true"
android:onClick="openProfile"
android:id="#+id/genFrom" />
Code from main activity that calls fragment:
public void openProfile(View v) {
Fragment_Questions frau = new Fragment_Questions();
frau.openProfile(v);
}
Code from fragment class:
public void openProfile(View v) {
View row = (View) v.getParent();
TextView child2 = (TextView) row.findViewById(R.id.genFromlogin);
String child3 = child2.getText().toString();
Intent ini = getActivity().getIntent();
String c_username = ini.getStringExtra(MainActivity.KEY_USERNAME);
String c_password = ini.getStringExtra(MainActivity.KEY_PASSWORD);
Intent ini2 = new Intent(context, User.class);
ini2.putExtra(MainActivity.KEY_USERNAME, c_username);
ini2.putExtra(MainActivity.KEY_PASSWORD, c_password);
ini2.putExtra(MainActivity.KEY_USER, child3);
getActivity().startActivity(ini2);
}
Errors:
java.lang.IllegalStateException: Could not execute method for android:onClick
...
...
...
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'android.content.Intent android.support.v4.app.FragmentActivity.getIntent()' on a null object reference
P.S.
1. App opens default activity
2. User calls a new activity with passing intent data
3. New activity calls fragment
The first (main) activity:
Intent intent_settings = getIntent();
String c_username = intent_settings.getStringExtra(MainActivity.KEY_USERNAME);
String c_password = intent_settings.getStringExtra(MainActivity.KEY_PASSWORD);
Intent intent_settings_1 = new Intent(this, NewFeed.class);
intent_settings_1.putExtra(MainActivity.KEY_USERNAME, c_username);
intent_settings_1.putExtra(MainActivity.KEY_PASSWORD, c_password);
intent_settings_1.setFlags(Intent.FLAG_ACTIVITY_NO_ANIMATION);
startActivity(intent_settings_1);
Okay, and you should know that all fragments are called by viewpager with tab layout.
#Override
public Fragment getItem(int position) {
switch (position) {
case 0:
Fragment_Home tab1 = new Fragment_Home();
return tab1;
case 1:
Fragment_Questions tab2 = new Fragment_Questions();
return tab2;
default:
return null;
}
}
You can only access the activity with getActivity() between calls to onAttach() and onDetach().
Fragment_Questions itself only seems to serve the purpose to start a new activity, so you could just move all the logic to the click listener of the activity and don't use the fragment at all.
If there's more about the fragment and you're actually planning to add it to the activity sometime in the future it still seems better to have this logic separated from the fragment. You only use getActivity() and magically context in there. You could just make it static and give the activity as parameter instead.
public static void openProfile(Activity activity, View v) {
View row = (View) v.getParent();
TextView child2 = (TextView) row.findViewById(R.id.genFromlogin);
String child3 = child2.getText().toString();
Intent ini = activity.getIntent();
String c_username = ini.getStringExtra(MainActivity.KEY_USERNAME);
String c_password = ini.getStringExtra(MainActivity.KEY_PASSWORD);
Intent ini2 = new Intent(activity, User.class);
ini2.putExtra(MainActivity.KEY_USERNAME, c_username);
ini2.putExtra(MainActivity.KEY_PASSWORD, c_password);
ini2.putExtra(MainActivity.KEY_USER, child3);
activity.startActivity(ini2);
}
You should add Fragment_Questions to Activity.
For example,In Activity layout:
<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"
tools:context=".MainActivity" >
<fragment
android:id="#+id/fragment_question"
android:name="com.example.view.Fragment_Questions"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
</LinearLayout>
In Acitivity.java:
questionFragment = (Fragment_Questions) findViewById(fragment_question);
and then, you can user OnClick Event like this:
questionFragment.openProfile(v);
You are getting Null Pointer Exception because your fragment is not attached to Activity. You are just instantiating the fragment and then calling its openProfile(View v) method which is a wrong way to handle events. If you already attached fragment then get the instance of framgent using
questionFragment = (Fragment_Questions) findViewById(fragment_question);
You can read below article on how to communicate from Fragments to activity
https://developer.android.com/training/basics/fragments/communicating.html
As I have understanded the steps of the user interferance you have to replace getIntent() in the fragment with the intent that starts it which is intent_settings i think
Also make the that intent static in order to share it
And make if statment in order not to have null exception
if(theIntent.hasPutextra)
{getExtra.....}
Do you extends Fragment OR FragmetnActivity?
if you extend FragmetnActivity (as i think) then dont use getActivity()
Also add the code for the intent that started your current activity
Fragment_Questions frau = new Fragment_Questions();
frau.openProfile(v);
You just created new fragment you didnt attached it to the activity?
use FragmentManager.
if you trying to use fragment inside ViewPager use THIS guide
I have the following layout defined in useful_numbers_item_fragment.xml:
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:id="#+id/call_linear_layout">
<LinearLayout
android:layout_width="0dp"
android:layout_height="wrap_content"
android:orientation="vertical">
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:id="#+id/useful_nums_item_name"/>
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:id="#+id/useful_nums_item_value"/>
</LinearLayout>
<ImageButton
android:layout_width="0dp"
android:layout_height="wrap_content"
android:src="#drawable/call"
android:id="#+id/call_btn"
android:onClick="callNumber"/>
</LinearLayout>
I dynamically populate the two text views in a class called UNItemListFragment.java
in the onCreate method:
public void onCreate(Bundle savedInstance) {
super.onCreate(savedInstance);
if (getArguments().containsKey(Constants.UNItem.GROUP_ID)) {
simpleCursorAdapter = new SimpleCursorAdapter(getActivity(), R.layout.useful_numbers_item_fragment, null,
new String[]{Constants.UNItem.NAME, Constants.UNItem.VALUE},
new int[]{R.id.useful_nums_item_name, R.id.useful_nums_item_value}, 0);
setListAdapter(simpleCursorAdapter);
getLoaderManager().initLoader(0, getArguments(), this);
}
}
For each number if i click on the button i want to make a phone call by
calling the callNumber method when the user clicks the button:
public void callNumber(View view) {
Intent callIntent = new Intent(Intent.ACTION_CALL);
TextView unItemVal = (TextView) findViewById(R.id.useful_nums_item_value);
String phoneNumber = unItemVal.getText().toString();
callIntent.setData(Uri.parse("tel:" + phoneNumber));
startActivity(callIntent);
}
It is ok when I click the first button in the list, but when I click on the other buttons
it continues calling the number defined in the first row...
Any idea how to resolve this?
The problem is that this line:
TextView unItemVal = (TextView) findViewById(R.id.useful_nums_item_value);
is executed on the activity, so the findViewById will always return the first item with that id, which is likely the first item in the list.
The best way to fix this would be to override the adapter and add a tag containing the phone number to the view. A quick way to fix this would be to tag along in the view hierarchy, like so:
public void callNumber(View view) {
if( view != null ) { // view is the button tapped
View parent = view.getParent(); // this should be the LinearLayout
if( parent instanceof LinearLayout ) {
TextView unItemVal = (TextView) ((LinearLayout)parent).findViewById(R.id.useful_nums_item_value);
if( unItemVal != null ) {
Intent callIntent = new Intent(Intent.ACTION_CALL);
String phoneNumber = unItemVal.getText().toString();
callIntent.setData(Uri.parse("tel:" + phoneNumber));
startActivity(callIntent);
}
}
}
}
This would find the parent for the button that was clicked, and then find the text-view containing the number within that ViewGroup.
Using findViewById() will return the first view in the activity or fragment with the specified id. If this is a ListView, it will correspond to the first row.
There are many ways to work around this problem. The quickest one (but certainly not the prettiest one, since it depends on the layout) would be to use findViewById() relative to the LinearLayout that contains the list item. Assuming that view is the ImageButton, it would be somthing like:
((View)view.getParent()).findViewById(R.id.useful_nums_item_value)
A more elegant solution would be to set a tag in the adapter's getView(), containing the data you need (in this case, the phone number to call).
I cannot for the life of me figure out why I'm getting a NullPointerException.
When a user clicks on a particular image, a dialog window is supposed to pop-up and display a larger version of said image:
private OnClickListener coverListener = new OnClickListener()
{
public void onClick(View v)
{
showDialog(DIALOG_COVER);
}
};
DIALOG_COVER is set to = 0.
The associated onCreateDialog looks like this:
protected Dialog onCreateDialog(int id) {
Dialog dialog;
switch(id)
{
case DIALOG_COVER:
dialog = new Dialog(mContext);
dialog.setContentView(R.layout.cover_dialog);
dialog.setTitle(book.getTitle());
ImageView coverLarge = (ImageView)findViewById(R.id.coverLarge);
coverLarge.setImageBitmap(book.getCover());
break;
default:
dialog = null;
}
return dialog;
}
For reference, this is cover_dialog.xml:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/coverDialog"
android:orientation="horizontal"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:padding="10dp">
<ImageView android:id="#+id/coverLarge"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:scaleType="fitStart"
/></LinearLayout>
Now, when the image previously described is clicked, the application immediately crashes and throws the following error through LogCat:
06-08 13:29:17.727: ERROR/AndroidRuntime(2220): Uncaught handler: thread main exiting due to uncaught exception
06-08 13:29:17.757: ERROR/AndroidRuntime(2220): java.lang.NullPointerException
06-08 13:29:17.757: ERROR/AndroidRuntime(2220): at org.kylehughes.android.brarian.AndroidBrarian.onCreateDialog(AndroidBrarian.java:259)
The line in question refers to this line inside of onCreateDialog:
coverLarge.setImageBitmap(book.getCover());
Basically, I don't get why coverLarge is null at that point. Any help would be much appreciated.
What's about:
/** snip **/
LayoutInflater factory = LayoutInflater.from(mContext);
View dialogView = factory.inflate(R.layout.cover_dialog,null);
ImageView coverLarge = (ImageView)dialogView.findViewById(R.id.coverLarge);
dialog = new Dialog(mContext);
dialog.setContentView(dialogView);
dialog.setTitle(book.getTitle());
coverLarge.setImageBitmap(book.getCover());
/** snip **/
Just written from scratch. Please check the syntax
This
(ImageView)findViewById(R.id.coverLarge);
returns a nullvalue. You may be passing an invalid/malformed id String to the findViewById method. Have you checked (debugged) what this String looks like before you get the NPE?
Is it possible that you have a different xml file defining the same ID (coverLarge) for a different kind of View (say a Button)? Also, notice how the id you use to setup the dialog is cover_dialog but in the XML file you have coverDialog
You have a few things going on at that line that some debug output would help. I'd start by System.out.println'ing the values of coverLarge and book immediately before the offending line. I know they shouldn't be null, but it wouldn't hurt to rule those possibilities out.