Develop Reference

Viewpager no longer swipeable after onClick is set on inflated View

I have a viewpager, which contain an image. If I create the image view using an xml layout as below
#Override
public Object instantiateItem(final ViewGroup container, final int position) {
final int realPosition = getItemPosition(position);
View view = LayoutInflater.from(mContext).inflate(R.layout.item_adsong, container, false);
ImageView imageView = (ImageView)view.findViewById(R.id.adsong_img);
/... set to the image.../
view.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
onClickPage(realPosition);
}
});
container.addView(view);
return view;
}
After adding the onClickListener, I can no longer swipe my view pager from page to page. Without the onClickListener, I could do so.
However, if I create my ImageView from the code (instead of using xml layout) as below
#Override
public Object instantiateItem(final ViewGroup container, final int position) {
final int realPosition = getItemPosition(position);
ImageView view = new ImageView(mContext);
/... set to the image.../
view.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
onClickPage(realPosition);
}
});
container.addView(view);
return view;
}
I could now swipe the view pager, and I could do the click as I like. Why my first example above is intercepting the swipe, while the second is not? How could I fix my first example above to allow both swipe and onClick still work (I prefers using the layout, as I have several more e.g. some TextViews than just ImageView to show in my view pager). Thanks!

After further thorough debug and investigation, found the issue as per https://groups.google.com/forum/#!topic/android-developers/wIqNP4fzJQc. The cause of the issue is because the existence of TextView in my .xml layout. The TextView is scrollable by default.
Given the TextView is scrollable, the ViewPager then would allow the text to scroll by not intercepting the scrolling touch, and passing to the child. Hence the scrolling touch of the ViewPager is not working.
To fix the problem I override the canScrollHorizontal function of the TextView to return false. This solve the problem
public class MyTextView extends TextView {
//...
#Override
public boolean canScrollHorizontally(int direction) {
return false;
}
//....
Note: using setHorizontallyScrolling(false) or setting the android:scrollHorizontally="false" attribute in the XML of the TextView doesn't solve the problem somehow.
Hope this helps some who face the ViewPager no longer scrollable issue.

Having problems setting up button of another layout

The problem is MainActivity starts with a setContentView with a layout.xml. We can add buttons or anything to the layout and code in in the MainActivity class but when I try to code the buttons of another layout in the same Activity the app forces stop . Whats wrong ?
Ok I found out that is because of the context.
When you try to change other activity you have to use layoutinflater. Example below
LayoutInflater inflater = getLayoutInflater();
View myLayout = inflater.inflate(R.layout.my_layout, null);
To work with widgets inside it like buttons or anything .
Button b = mylayout.findViewById(R.id.button);
b.setText("Successfully changed");
Now you can use myLayout as your changed layout.

Please sent me your Activities
What the text of problem ?
You may write next code to go to another activity
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
startActivity(new Intent(getApplicationContext(),nameActivity.class));
}
});
Where button is name of your button
See that you xml-file doesnt have any mistakes

You are getting a crash because you are trying to access the layout when it is not inflated. In other words, you must call setContentView() on an Activity, or inflater.inflate() on a Fragment to instantiate the view and make the elements accessible for manipulation. So if you want to add buttons to another Activity, you would need to call its onCreate() and setContentView() before you can add buttons to it.
EDIT: In response to comments...
In order to access/manipulate/modify elements in a layout at runtime, they must first be instantiated, which happens when the view is inflated. So to add a button to an Activity at runtime, you would do it in the onCreate() method after calling setContentView() like this:
Keep in mind this is the onCreate() of your SECOND activity...not your main Activity. So your main activity would start this Activity, then the button would get created during the setup of the second Activity.
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.your_second_activity;
Button button = new Button(this);
button.setText("Your New Button");
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Log.d("NEW BUTTON", "I just clicked my new button!");
}
});
RelativeLayout relativeLayout = (RelativeLayout) findViewById(R.id.layout_in_your_second_activity);
relativeLayout.addView(button);
}
If you are using a Fragment to display your UI, you can't access your UI elements until you have inflated your layout, which happens in the onCreateView() method. So you would do something like this in your Fragment code:
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.your_fragment_layout, container, false);
RelativeLayout relativeLayout = (RelativeLayout) view.findViewById(R.id.container_layout_that_holds_button);
//You would get your context from an onAttach() Override
Button button = new Button(context);
button.setText("Your New Button");
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Log.d("NEW BUTTON", "I just clicked my new button!");
}
});
relativeLayout.addView(button);
return view;
}
You're likely getting a NullPointerException when you try to manipulate your layouts before they are created. Keep in mind that even if you have an XML file with layouts specified within, the actual objects for those elements won't be created until the system decides it needs them, which happens when you actually try to display the view.

inflates 2 views using same xml:second view contains properties of first view

When changing the text of TextView of the first view, the textView's text of the second view shows the text of both TextViews, one on top of the other.
MainActivity.java
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
FrameLayout rl=(FrameLayout) findViewById(R.id.mainLayout);
View v1=LayoutInflater.from(this).inflate(R.layout.text_view, null);
View v2=LayoutInflater.from(this).inflate(R.layout.text_view, null);
TextView myTextView1= (TextView) v1.findViewById(R.id.myTextView);
TextView myTextView2= (TextView) v2.findViewById(R.id.myTextView);
myTextView1.setText("str1");
myTextView2.setText("str2");
rl.addView(v1);
rl.addView(v2);
}

I would guess the issue is because you are using a framelayout so the subviews will overlap. If you switch that framelayout to a linearlayout for example I imagine the results will be as you expect according to the textviews.

very simple.. 1. you have to use append property rather than settext in second textview
2nd you can use extras to pass using intent or use getter setter method like
public static void setstr_name(String str_name) {
GlobalVariable.str_name = str_name;
}
public static String getstr_name() {
return str_name;
}

how to display new activity over another activity?

i have an activity that displays two buttons , on click of call button i want to show another activity as shown in image.
Please help .How to achieve this

One way to do it is to have a custom layout which you add to each activity with a viewgroup as such:
private View view;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
ViewGroup parent = (ViewGroup) findViewById(R.id.linearLayout1);
view = LayoutInflater.from(getBaseContext()).inflate(R.layout.custom_layout,
null);
parent.addView(view);
Then you just need to implement your listeners and whatnot further down :)

You need to create xml file of these two buttons and add that new xml into old one by using Layout Inflator. for e.g
1) your new xml
LayoutInflator buttons = LayoutInflater.from(getBaseContext()).inflate(R.layout.buttons,
currentxml, false);
2) your old xml parent referenced through id -->
RelativeLayout relativeLayout = (RelatveLayout) findViewById(R.id.oldxml);
3) now add..
relativeLayout.addView(buttons);

You can Use Pop up By Adding this in your function. Popuser is a xml file which you want to inflate.
public void popupshow(){
try{
LayoutInflater inflater=(LayoutInflater)SRSDMain.this.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
Display display=getWindowManager().getDefaultDisplay();
int width=display.getWidth()/2;
int height=display.getHeight()/2;
View pop=inflater.inflate(R.layout.popupuser,null,false);
pop.measure(View.MeasureSpec.UNSPECIFIED,View.MeasureSpec.UNSPECIFIED);
height=pop.getMeasuredHeight();
width=pop.getMeasuredWidth()+50;
pu=new PopupWindow(pop,width,height,true);
pu.showAtLocation(findViewById(R.id.ll3),Gravity.CENTER,1,1);
Button btn=(Button)pu.getContentView().findViewById(R.id.button);
btn.getBackground().setColorFilter(new LightingColorFilter(0xFF505450,0xFF101010));
btn.setTextColor(Color.WHITE);
btn.setTypeface(null,Typeface.BOLD);
btn.setOnClickListener(new View.OnClickListener(){
public void onClick(View v){
//anything you want to do
pu.dismiss();
}
});
}
catch(Exception ex){
//Catch The Exception
}
}
}

Replace a view with other view By code

I want to replace a view with other other by code
For example i need to change a imageview to progressBar by code.
public void changeToProgressBar(ImageView imageview,Context context){
ProgressBar one = new ProgressBar(context);
one.setLayoutParams(imageview.getLayoutParams());
imageview.setVisibility(View.GONE);
one.setVisibility(View.VISIBLE);
//NOW I NEED TO PLACE 'one' EXACTLY THE PLACE WHERE 'imageview' WAS THERE
}
I need to use this many place. I know to set by sending the parent viewgroup.
Is there anyway to get the parent viewgroup from imageview
Thanks

This is trivial to do and other posters have linked to or hinted at the solution. You can get the parent of a View by View.getParent(). You need to cast the returned value to a ViewGroup (q: can a View's parent be anything else than a ViewGroup?). Once you have the parent as a ViewGroup you can do ViewGroup.removeChild(viewToRemove) to remove the old view and add the new one using ViewGroup.addChild(viewToAdd).
You might also want to add the new view at the same index as the remove view to make sure that you don't put the new view on top of or below other views. Here's a complete utility class for you to use:
import android.view.View;
import android.view.ViewGroup;
public class ViewGroupUtils {
public static ViewGroup getParent(View view) {
return (ViewGroup)view.getParent();
}
public static void removeView(View view) {
ViewGroup parent = getParent(view);
if(parent != null) {
parent.removeView(view);
}
}
public static void replaceView(View currentView, View newView) {
ViewGroup parent = getParent(currentView);
if(parent == null) {
return;
}
final int index = parent.indexOfChild(currentView);
removeView(currentView);
removeView(newView);
parent.addView(newView, index);
}
}
Something to consider is that you'll lose any positioning in a relative layout when you replace one view with another. One solution to this would be to make sure that the view you want to replace is wrapped in a another view and that wrapped container view is the one that is positioned in a relative layout.

Retrieve the view you would like to change by calling findViewById() from the activity level http://developer.android.com/reference/android/app/Activity.html#findViewById(int) Then find the sub view you would like to change http://developer.android.com/reference/android/view/View.html#findViewById(int)
Then use the functions from http://developer.android.com/reference/android/view/ViewGroup.html to manipulate the view.

Just as User333 described that could be one solution..
It's also possible to delete the imageview by calling yourview.removeView(imageview) and then create your progress bar and put that inside the view instead by yourview.addView(progressbar)

You can change Android Activities view from any other simple java class or in other activity.
you only need to pass current view and get your element by this view you want to change As :
public class MainActivity extends Activity{
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Setting UI
View currentView = getWindow().getDecorView().getRootView();
//showHeaderLayout is simple java class or it can be any activity
changeLayout.setView(currentView);
}
Class : changeLayout
public class changeLayout{
public static View setView(final Activity activity, final View myView)
{
// myView helps to get Activity view , which we want to change.
TextView tv = (TextView) myView.findViewById(R.id.tv);
tv.setText("changs Text Via other java class !!");
}
}
Note : Passing view makes you able to change any activity view outside an Activity.

I think following ould be the best approach as in this we don't need to set layout params.
setvisibility(Visibility.GONE)
setvisibility(Visibility.VISIBLE)

I am sure that following link not only help you, but even shows you the direction for your requirement. https://stackoverflow.com/a/3760027/3133932

For this, take both imageview and progressBar and set the visibility according to your requirements.
For example
If you want progressBar to be visible, put setvisibility(Visibility.GONE) for imageview and put setvisibility(Visibility.VISIBLE) for progressBar