Develop Reference

TextView not showing up after activity switch

My main activity(one xml file, and one java file) contains a help button, and I want to display the whole layout(including the paragraph I typed on a Textview) after button clicked. It was successfully launched, all imageview were displayed but not the Textview.
Here's the content of the xml file:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#drawable/tbs_background"
tools:context="limitless.the_bat_signal.aboutPage">
<TextView
tools:text="about the app"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/tbs_text_about"
android:textStyle="normal|italic"
android:textAlignment="center"
android:textColor="#android:color/darker_gray"
android:fontFamily="sans-serif"
android:layout_below="#+id/tbs_title_text"
android:layout_centerHorizontal="true"
tools:ignore="UnusedAttribute" />
<TextView
tools:text="#string/about"
android:id="#+id/tbs_text_aboutDetails"
android:layout_width="300dp"
android:textColor="#android:color/darker_gray"
android:textSize="16sp"
android:layout_height="wrap_content"
android:layout_below="#+id/tbs_text_about"
android:layout_centerHorizontal="true"
android:layout_marginTop="12dp" />
<ImageView
android:layout_height="wrap_content"
app:srcCompat="#drawable/tbs_title_text"
android:id="#+id/tbs_title_text"
android:adjustViewBounds="true"
android:layout_width="250dp"
android:layout_below="#+id/tbs_icon"
android:layout_centerHorizontal="true"
tools:ignore="ContentDescription" />
<ImageView
app:srcCompat="#drawable/tbs_icon"
android:layout_marginTop="14dp"
android:id="#+id/tbs_icon"
android:layout_width="128dp"
android:layout_height="128dp"
tools:ignore="ContentDescription"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true" />
<Button
android:id="#+id/tbs_home"
android:background="#drawable/tbs_home"
android:layout_width="56dp"
android:layout_height="56dp"
android:layout_alignParentBottom="true"
android:layout_toRightOf="#+id/tbs_title_text"
android:layout_toEndOf="#+id/tbs_title_text"
android:layout_marginBottom="10dp" />
</RelativeLayout>.
Then my Activity 2 named aboutPage calling out the XML file above:
public class aboutPage extends AppCompatActivity {
Button btn_help;
TextView tbs_title_text;
TextView tbs_text_about_details;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_about);
}
}.
I'm new to android, please tell me what am I missing. Thanks!

The text attribute in your code is wrong, the namespace should be android:text="#string/about" instead of tools:text=="#string/about".
So the resulting textview will look like,
<TextView
android:text="about the app"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/tbs_text_about"
android:textStyle="normal|italic"
android:textAlignment="center"
android:textColor="#android:color/darker_gray"
android:fontFamily="sans-serif"
android:layout_below="#+id/tbs_title_text"
android:layout_centerHorizontal="true"
tools:ignore="UnusedAttribute" />
Fix it and you will be good to go.

The problem is you're using tools:text this is only for design view and will not translate to code. Use android:text instead.

Android XML ImageView below TextView but needs to align bottom with textView

So My text View has to be drawn over the image view, so its defined in xml like this:
<ImageView
android:id="#+id/chatBalloon"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:layout_marginLeft="-5dp"
android:layout_marginRight="-5dp"
android:layout_marginTop="2dp"
android:layout_toRightOf="#+id/chatItemProfPic"
android:scaleType="fitXY"
android:src="#drawable/chat_bar_user" />
<TextView
android:id="#+id/userText"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_marginLeft="7dp"
android:layout_marginTop="3dp"
android:layout_toRightOf="#+id/chatItemProfPic"
android:text="username"
android:textAppearance="?android:attr/textAppearanceMedium"
android:textSize="15sp" />
but i because the textView can contain multiline text, i need to have the imageView increase its height accordingly. It would be accomplished by adding this rule:
android:layout_alignBottom="idOfText"
but because the textView hasnt been defined at that part, the app crashes. I get the same when trying to do it from code by addRule in the LayoutParams because i call it in onCreate, before the view has been drawn.
Any ideas how to bypass this?
SOLVED:
Final xml:
<ImageView
android:id="#+id/chatBalloon"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:layout_marginLeft="-5dp"
android:layout_marginRight="-5dp"
android:layout_marginTop="2dp"
android:layout_toRightOf="#+id/chatItemProfPic"
android:scaleType="fitXY"
android:layout_alignBottom="#+id/userText"
android:src="#drawable/chat_bar_user" />
<TextView
android:id="#id/userText"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_marginLeft="7dp"
android:layout_marginTop="3dp"
android:layout_toRightOf="#+id/chatItemProfPic"
android:text="username"
android:textAppearance="?android:attr/textAppearanceMedium"
android:textSize="15sp" />

You use
android:layout_alignBottom="#+id/idOfText"
when you first make a reference to a particular id. Note the "+" which is adding the id to the list of resource identifiers.
Then, you can assign an existing id to a widget without using the "+", as follows:
android:id="#id/idOfText"
after. It's typical to create the id when we're assigning it, which is why you only really need to care about the presence of the "+" in relative layouts.
In your specific case:
<ImageView
android:id="#+id/chatBalloon"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:layout_marginLeft="-5dp"
android:layout_marginRight="-5dp"
android:layout_marginTop="2dp"
android:layout_toRightOf="#id/chatItemProfPic"
android:layout_alignBottom="#+id/userText"
android:scaleType="fitXY"
android:src="#drawable/chat_bar_user" />
<TextView
android:id="#id/userText"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_marginLeft="7dp"
android:layout_marginTop="3dp"
android:layout_toRightOf="#id/chatItemProfPic"
android:text="username"
android:textAppearance="?android:attr/textAppearanceMedium"
android:textSize="15sp" />
You should have set the ID of the profile pic widget using: android:id = "#+id/chatItemProfPic" assuming that you are declaring the widget before any references to it. Otherwise, similarly, use "+" for the first reference, and then assign the ID when you declare the widget without the "+".

why dont put that image like textview background.?
or something like:
<RelativeLayout
android:id="#+id/Rlayout"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginRight="35dp" >
<ImageView
android:id="#+id/image"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:src="#drawable/img" />
<TextView
android:id="#+id/text"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true"
android:text="lorem ipsum"
android:textAppearance="?android:attr/textAppearanceSmall"
android:textSize="#dimen/dimension" />
</RelativeLayout>
in relative layout you could easily put text right over imageview

Popup message like Dialog

I'm actually coding an app for Android and I need some help to do something.
I need to do a kind of popup message with this image: http://img716.imageshack.us/img716/9331/postitz.png. This image must have 2 TextView, one of them is a title and the other one is the message.
I have tried some options like Dialog with its own layout, own style, but the image fills all the screen instead of wrap the content of the TextViews. I have also tried to do it with a new Activity and occurs the same, the Image fills all the screen.
My actual layout is this:
<?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"
android:gravity="center_vertical"
android:background="#android:color/white">
<LinearLayout
android:id="#+id/img_postit"
android:layout_height="wrap_content"
android:layout_width="wrap_content"
android:background="#drawable/postit"
android:orientation="vertical">
<TextView
android:id="#+id/note_titulo"
android:layout_height="wrap_content"
android:layout_width="wrap_content"
android:padding="30dp"/>
<TextView
android:id="#+id/note_descr"
android:layout_height="wrap_content"
android:layout_width="wrap_content"
android:padding="30dp"/>
</LinearLayout>
</LinearLayout>
But I have tried with a lot of different combinations, RelativeLayout, FrameLayout, and I cannot find the solution to do this.
Any idea of how to resolve it?.
Thank's for all.

you said you used as a new activity. Did you use android:theme="#android:style/Theme.Dialog in your manifest file?
And be sure that the image is little bit smaller one such that it will be suitable to act as a pop up..
If you used a dialog what exactly is the problem? Didnt you get the dialog as a pop up ?
(i think the image is larger so that it might fill the entire screen)

Create your own class extending dialog.And use layout like following. I use this in one of my apps and the dialog window is wrapped around the buttons :
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#drawable/background"
android:orientation="vertical" >
<RelativeLayout
android:id="#+id/ll2"
android:layout_width="fill_parent"
android:layout_height="70dp"
android:layout_below="#+id/ll1"
android:gravity="left"
android:orientation="horizontal"
android:paddingBottom="5dp" >
<RadioButton
android:id="#+id/start"
android:layout_width="70dp"
android:layout_height="70dp"
android:layout_alignParentBottom="true"
android:layout_toLeftOf="#+id/stop"
android:background="#drawable/start_on"
android:button="#android:color/transparent"
android:checked="true" />
<RadioButton
android:id="#+id/stop"
android:layout_width="70dp"
android:layout_height="70dp"
android:layout_alignParentBottom="true"
android:layout_centerInParent="true"
android:layout_marginLeft="50dp"
android:layout_marginRight="50dp"
android:background="#drawable/stop_off"
android:button="#android:color/transparent" />
<RadioButton
android:id="#+id/restart"
android:layout_width="70dp"
android:layout_height="70dp"
android:layout_alignParentBottom="true"
android:layout_toRightOf="#+id/stop"
android:background="#drawable/restart_on"
android:button="#android:color/transparent" />
</RelativeLayout>
<RelativeLayout
android:id="#+id/lltext"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_above="#+id/detail_credit"
android:layout_below="#+id/ll2"
android:layout_marginBottom="15dp"
android:orientation="horizontal" >
<TextView
android:id="#+id/startText"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_toLeftOf="#+id/stopText"
android:text="#string/start_server_icon"
android:textAppearance="?android:attr/textAppearanceLarge"
android:textColor="#android:color/white"
android:textSize="12sp"
android:textStyle="bold" />
<TextView
android:id="#+id/stopText"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_marginLeft="40dp"
android:layout_marginRight="40dp"
android:text="#string/stop_server_icon"
android:textAppearance="?android:attr/textAppearanceLarge"
android:textColor="#android:color/white"
android:textSize="12sp"
android:textStyle="bold" />
<TextView
android:id="#+id/restartText"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_toRightOf="#+id/stopText"
android:text="#string/restart_server_icon"
android:textAppearance="?android:attr/textAppearanceLarge"
android:textColor="#android:color/white"
android:textSize="12sp"
android:textStyle="bold" />
</RelativeLayout>
<Button
android:id="#+id/dialogButtonOK"
android:layout_width="wrap_content"
android:layout_height="50dp"
android:layout_below="#+id/lltext"
android:layout_centerHorizontal="true"
android:text="OK" />
</RelativeLayout>

final Dialog dialog_my = new Dialog(FIRST.this,
android.R.style.Theme_Translucent_NoTitleBar_Fullscreen);
dialog_my.setContentView(R.layout.about_us); //<PUT YOUR LAYOUT ID HERE>
TextView date = (TextView) dialog_my.findViewById(R.id.date);
TextView thought = (TextView) dialog_my.findViewById(R.id.thought);
TextView ok = (TextView) dialog_my.findViewById(R.id.ok);
TextView link = (TextView) dialog_my.findViewById(R.id.link);
TextView contact = (TextView) dialog_my.findViewById(R.id.contact);
WindowManager.LayoutParams lp = dialog_my.getWindow().getAttributes();
lp.dimAmount = 0.0f;
dialog_my.getWindow().setAttributes(lp);
dialog_my.getWindow().addFlags(
WindowManager.LayoutParams.FLAG_DIM_BEHIND);
dialog_my.show();

findviewbyid returns null (Textview)

when i try to set the text of an textview i get a nullpointerexception. somehow the findviewbyid method return null but i dont know why.
this is my xml file:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content" >
<RelativeLayout
android:id="#+id/rl_ros_layout1"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_alignParentTop="true" >
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:text="#+id/tv_ros_view1"
android:textAppearance="?android:attr/textAppearanceMedium" />
<ProgressBar
android:id="#+id/pb_ros_bar1"
style="?android:attr/progressBarStyleSmall"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:layout_alignParentTop="true"
android:visibility="invisible" />
</RelativeLayout>
<ScrollView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_below="#+id/rl_ros_layout1" >
<TableLayout
android:id="#+id/tl_rostertable"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:stretchColumns="2" >
<TableRow
android:layout_width="fill_parent"
android:layout_height="wrap_content" >
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:padding="3dp"
android:text="#string/team" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:padding="3dp"
android:text="#string/pos" />
<TextView
android:layout_height="wrap_content"
android:padding="3dp"
android:text="#string/name" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="right"
android:padding="3dp"
android:text="#string/score" />
</TableRow>
</TableLayout>
</ScrollView>
</RelativeLayout>
and my oncreate method
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.roster);
final Bundle extra = getIntent().getExtras();
position = extra.getInt("pos");
int id = de.damps.fantasy.HomeActivity.ID[position];
url = de.damps.fantasy.HomeActivity.URL + "/roster/2011/" + id;
tbl = (TableLayout) findViewById(R.id.tl_rostertable);
team = (TextView) findViewById(R.id.tv_ros_view1);
String s= de.damps.fantasy.HomeActivity.TEAMS[position];
team.setText(s);
new GetRoster().execute(url);
}
the tablelayout is found without any problmes. but the textview is null.
i already cleaned the project but it didnt solve the problem
would be nice if someone can help me

You have a typo:
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:id="#+id/tv_ros_view1"
android:textAppearance="?android:attr/textAppearanceMedium" />
(android:text instead of android:id)

You wrote
android:text="#+id/tv_ros_view1"
instead of
android:id

you create ID your text view like this android:id="#+id/tv_ros_view1" in place of android:text="#+id/tv_ros_view1" this is use full to you.

In you xml layout:
android:text="#+id/tv_ros_view1"
should be:
android:id="#+id/tv_ros_view1"
the text attribute is used to tell textview what text to show.

In your faulty/first text view you have written like this:
android:text="#+id/tv_ros_view1"
Just replace this with this:
android:id="#+id/tv_ros_view1"
This is how you have to assign id to a view(TextView).

Visibility of TextView in Dialog

I have a dialog, which is created with this code:
final Dialog dialog1 = new Dialog(Test.this);
dialog1.requestWindowFeature(Window.FEATURE_NO_TITLE);
dialog1.setContentView(R.layout.test_layout);
dialog1.setCancelable(true);
...
The layout file 'test_layout.xml' contains a typical TextView:
<TextView
android:id="#+id/tv_username"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:paddingLeft="10dp"
android:textAppearance="?android:attr/textAppearanceMedium"
android:text="Test" />
I want in the code to set this TextView invisible (gone) in some cases.
I tried following:
TextView tv = (TextView) dialog1.findViewById(R.id.tv_username);
tv.setVisibility(TextView.GONE);
But the TextView still appears in the dialog. If I set in the layout xml file android:visibility="gone" it is not appearing in the dialog. But I need to do it via code.
Here the whole code:
if (whichButton == 1) {
final Dialog dialog1 = new Dialog(Test.this);
dialog1.requestWindowFeature(Window.FEATURE_NO_TITLE);
dialog1.setContentView(R.layout.test_layout);
dialog1.setCancelable(true);
TextView tv = (TextView) dialog1.findViewById(R.id.tv_username);
tv.setVisibility(View.GONE);
...
dialog1.show();
}
Here the whole XML file:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="250dp"
android:layout_height="match_parent"
>
<TextView
android:id="#+id/tv_name"
android:paddingTop="10dp"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:paddingLeft="15dp"
android:textSize="14dp"
android:text="Name:" />
<EditText
android:id="#+id/username"
android:hint="#string/enterName"
android:layout_height="wrap_content"
android:layout_width="fill_parent"
android:maxLength="15"
android:layout_marginLeft="10dp"
android:layout_marginRight="10dp"
android:scrollHorizontally="true"
android:capitalize="words"
android:singleLine="true"
android:gravity="fill_horizontal"
android:textAppearance="?android:attr/textAppearanceMedium" />
<TextView
android:id="#+id/tv_username"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:paddingLeft="10dp"
android:textAppearance="?android:attr/textAppearanceMedium"
android:text="Test" />
<TextView
android:id="#+id/tv_message"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:paddingLeft="15dp"
android:textSize="14dp"
android:text="#string/message" />
<EditText
android:id="#+id/tip"
android:layout_height="wrap_content"
android:layout_width="fill_parent"
android:maxLength="290"
android:layout_marginLeft="10dp"
android:layout_marginRight="10dp"
android:scrollbars="vertical"
android:inputType="textMultiLine"
android:capitalize="words"
android:gravity="fill_horizontal"
android:textAppearance="?android:attr/textAppearanceMedium" />
<Button
android:id="#+id/button"
android:layout_marginLeft="10dp"
android:layout_marginRight="10dp"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="#string/send_message" />
</LinearLayout>

Try tv.setVisibility(View.INVISIBLE);

I found a solution or workaround.
The dialog was created in the the onClick method of an AlertDialog.
Now I use the showDialog() method and handle it in the corresponding callback method.
There it is working fine.
I do not understand why this is working, but I only want to tell other users how they can solve this issue.
I would be happy if someone can come up with a clarification.