How to display auto-scorlling text (marquee)

If you want to display which keeps scrolling automatically on a single line textview, you can use the following steps.

First of all, in your xml file, set the following properties for your textview

android:singleline = "true"

android:ellipsize="marquee"

But still you see that your text is showing marquee. Please remember that the text will auto-scroll only when it has focus or it is selected.

So add the following text in your code.

yourtextview.setSelected(true);

Now you can see that your text view will display auto scrolling text

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Simple ListView Adapter and list item select

When you are using a listview in your applications many a times you will write your own adapter to display item. But if your list is very simple showing a list of strings, you can use inbuilt adapters like ArrayAdapter, SimpleCursorAdapter etc.

ArrayAdapterLet us look at an example

<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent" > <ListView android:layout_height="wrap_content" android:id="@+id/listView1" android:layout_width="match_parent" android:layout_margin="20dp"> </ListView> </LinearLayout>

And add these lines to the onCreate method of the activity.

super.onCreate(savedInstanceState); …

Drawables in Android - Layer drawable

Let us see how to use layer drawable. You can have two or more bitmaps on different layers to create such a drawable

Using xml:

You should use layer-list in your xml file to create layerdrawable. Here is layer.xml
<?xml version="1.0" encoding="utf-8"?> <layer-list xmlns:android="http://schemas.android.com/apk/res/android"> <item> <bitmap android:src="@drawable/whiteicon" android:gravity="top|left"/> </item> <item> <bitmap android:src="@drawable/blueicon" android:gravity="top|left"/> </item> <item> <bitmap android:src="@drawable/redicon" android:gravity="top|left"/> </item> </layer-list>
We are using three different bitmaps whiteicon.png, redicon.png and blueicon.png which are present in /res/drawable/mdpi folder. All these are of different sizes and aligned to top left. This drawab…

DatePickers in Android

DatePicker is a view which lets the user select a date showing a calendar or 3 spinners for dd, mm and yy.

Let us see how to use this.
Easy Method: To use a DatePicker you can use DatePickerDialog. This can be created and shown programmatically too.

publicvoidonCreate(Bundle b){/*********/ Button btn =(Button)findViewById(R.id.btn); btn.setOnClickListener(new View.OnClickListener(){@OverridepublicvoidonClick(View v){ showPickerDialog();}});}privatevoidshowPickerDialog(){ DatePickerDialog dtPickerDlg =new DatePickerDialog(this,this, 2017,10,20); dtPickerDialog.show();}

In our xml file, let us have a button and in the onclick listener of the button, let us display the date picker dialog - we call showPickerDialog.

In showPickerDialog, we are using a random date to initialize.

The first parameter is the context. Second parameter is the class which implements the interface OnDateSetListener. Next three parameters are year, month (Jan is 0) and …

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