Category: C#, Android, VS2015; Creation date: 2016-02-06 This chapter mainly introduces the basic usage of Android simple controls. There are 9 examples in the source program of this chapter, and these examples are all in the same project. Project name: ch05demos, project template: Blank App (Android). The screenshot of the main running interface is as follows: Click on the example item in each row to enter the corresponding display
Category: C#, Android, VS2015;
Creation date: 2016-02-06
This chapter mainly introduces the basic usage of Android simple controls. There are 9 examples in the source program of this chapter, and these examples are all in the same project.
Project name: ch05demos, project template: Blank App(Android)
The screenshot of the main running interface is as follows:
Click on the example item in each row to enter the page of the corresponding example.
See the left picture below for the added pictures. You can also drag and drop the pictures directly into the drawable folder.
The picture on the right shows the vertical screen layout file (layout folder), horizontal screen layout file (layout-land folder), and pop-up menu layout file (menu folder) after the examples in each section are implemented. These are added in the sections that will be introduced later in this chapter.
The modified code is as follows:
<span style="color: #0000ff;"></span><span style="color: #ff00ff;">xml version="1.0" encoding="utf-8"</span><span style="color: #0000ff;">?></span> <span style="color: #0000ff;"><span style="color: #800000;">LinearLayout </span><span style="color: #ff0000;">xmlns:android</span><span style="color: #0000ff;">="http://schemas.android.com/apk/res/android"</span><span style="color: #ff0000;"> android:orientation</span><span style="color: #0000ff;">="vertical"</span><span style="color: #ff0000;"> android:layout_width</span><span style="color: #0000ff;">="fill_parent"</span><span style="color: #ff0000;"> android:layout_height</span><span style="color: #0000ff;">="fill_parent"</span><span style="color: #0000ff;">></span> <span style="color: #0000ff;"><span style="color: #800000;">ListView </span><span style="color: #ff0000;">android:minWidth</span><span style="color: #0000ff;">="25px"</span><span style="color: #ff0000;"> android:minHeight</span><span style="color: #0000ff;">="25px"</span><span style="color: #ff0000;"> android:layout_width</span><span style="color: #0000ff;">="match_parent"</span><span style="color: #ff0000;"> android:layout_height</span><span style="color: #0000ff;">="match_parent"</span><span style="color: #ff0000;"> android:id</span><span style="color: #0000ff;">="@+id/listView1"</span> <span style="color: #0000ff;">/></span> <span style="color: #0000ff;"></span><span style="color: #800000;">LinearLayout</span><span style="color: #0000ff;">></span></span></span>
After all the examples in this chapter are completed, the code of MainActivity.cs is as follows:
<span style="color: #0000ff;">using</span><span style="color: #000000;"> System; </span><span style="color: #0000ff;">using</span><span style="color: #000000;"> Android.App; </span><span style="color: #0000ff;">using</span><span style="color: #000000;"> Android.Widget; </span><span style="color: #0000ff;">using</span><span style="color: #000000;"> Android.OS; </span><span style="color: #0000ff;">using</span><span style="color: #000000;"> ch05demos.SrcActivity; </span><span style="color: #0000ff;">namespace</span><span style="color: #000000;"> ch05demos { [Activity(Label </span>= <span style="color: #800000;">"</span><span style="color: #800000;">ch05demos</span><span style="color: #800000;">"</span>, MainLauncher = <span style="color: #0000ff;">true</span>, Icon = <span style="color: #800000;">"</span><span style="color: #800000;">@drawable/icon</span><span style="color: #800000;">"</span><span style="color: #000000;">)] </span><span style="color: #0000ff;">public</span> <span style="color: #0000ff;">class</span><span style="color: #000000;"> MainActivity : Activity { </span><span style="color: #0000ff;">string</span><span style="color: #000000;">[] items; </span><span style="color: #0000ff;">PRotected</span> <span style="color: #0000ff;">override</span> <span style="color: #0000ff;">void</span><span style="color: #000000;"> OnCreate(Bundle bundle) { </span><span style="color: #0000ff;">base</span><span style="color: #000000;">.OnCreate(bundle); SetContentView(Resource.Layout.Main); items </span>= <span style="color: #0000ff;">new</span> <span style="color: #0000ff;">string</span><span style="color: #000000;">[] { </span><span style="color: #800000;">"</span><span style="color: #800000;">Demo01EditText</span><span style="color: #800000;">"</span><span style="color: #000000;">, </span><span style="color: #800000;">"</span><span style="color: #800000;">Demo02Login</span><span style="color: #800000;">"</span><span style="color: #000000;">, </span><span style="color: #800000;">"</span><span style="color: #800000;">Demo03MultiResolution</span><span style="color: #800000;">"</span><span style="color: #000000;">, </span><span style="color: #800000;">"</span><span style="color: #800000;">Demo04CheckBoxRadioButton</span><span style="color: #800000;">"</span><span style="color: #000000;">, </span><span style="color: #800000;">"</span><span style="color: #800000;">Demo05Spinner</span><span style="color: #800000;">"</span><span style="color: #000000;">, </span><span style="color: #800000;">"</span><span style="color: #800000;">Demo06SwitchAndRatingBar</span><span style="color: #800000;">"</span><span style="color: #000000;">, </span><span style="color: #800000;">"</span><span style="color: #800000;">Demo07PopupMenu</span><span style="color: #800000;">"</span><span style="color: #000000;">, </span><span style="color: #800000;">"</span><span style="color: #800000;">Demo08Gallery</span><span style="color: #800000;">"</span><span style="color: #000000;">, </span><span style="color: #800000;">"</span><span style="color: #800000;">Demo09SeekBar</span><span style="color: #800000;">"</span><span style="color: #000000;"> }; ListView listView1 </span>= FindViewById<listview><span style="color: #000000;">(Resource.Id.listView1); listView1.Adapter </span>= <span style="color: #0000ff;">new</span> ArrayAdapterstring>(<span style="color: #0000ff;">this</span><span style="color: #000000;">, </span><span style="color: #000000;">Android.Resource.Layout.SimpleListItem1, items); listView1.ItemClick </span>+= (s, e) =><span style="color: #000000;"> { </span><span style="color: #0000ff;">int</span> index = e.Position + <span style="color: #800080;">1</span><span style="color: #000000;">; </span><span style="color: #0000ff;">switch</span><span style="color: #000000;">(index) { </span><span style="color: #0000ff;">case</span> <span style="color: #800080;">1</span><span style="color: #000000;">: StartActivity(</span><span style="color: #0000ff;">typeof</span><span style="color: #000000;">(Demo01EditText)); </span><span style="color: #0000ff;">break</span><span style="color: #000000;">; </span><span style="color: #0000ff;">case</span> <span style="color: #800080;">2</span><span style="color: #000000;">: StartActivity(</span><span style="color: #0000ff;">typeof</span><span style="color: #000000;">(Demo02Login)); </span><span style="color: #0000ff;">break</span><span style="color: #000000;">; </span><span style="color: #0000ff;">case</span> <span style="color: #800080;">3</span><span style="color: #000000;">: StartActivity(</span><span style="color: #0000ff;">typeof</span><span style="color: #000000;">(Demo03MultiResolution)); </span><span style="color: #0000ff;">break</span><span style="color: #000000;">; </span><span style="color: #0000ff;">case</span> <span style="color: #800080;">4</span><span style="color: #000000;">: StartActivity(</span><span style="color: #0000ff;">typeof</span><span style="color: #000000;">(Demo04CheckBoxRadioButton)); </span><span style="color: #0000ff;">break</span><span style="color: #000000;">; </span><span style="color: #0000ff;">case</span> <span style="color: #800080;">5</span><span style="color: #000000;">: StartActivity(</span><span style="color: #0000ff;">typeof</span><span style="color: #000000;">(Demo05Spinner)); </span><span style="color: #0000ff;">break</span><span style="color: #000000;">; </span><span style="color: #0000ff;">case</span> <span style="color: #800080;">6</span><span style="color: #000000;">: StartActivity(</span><span style="color: #0000ff;">typeof</span><span style="color: #000000;">(Demo06SwitchAndRatingBar)); </span><span style="color: #0000ff;">break</span><span style="color: #000000;">; </span><span style="color: #0000ff;">case</span> <span style="color: #800080;">7</span><span style="color: #000000;">: StartActivity(</span><span style="color: #0000ff;">typeof</span><span style="color: #000000;">(Demo07PopupMenu)); </span><span style="color: #0000ff;">break</span><span style="color: #000000;">; </span><span style="color: #0000ff;">case</span> <span style="color: #800080;">8</span><span style="color: #000000;">: StartActivity(</span><span style="color: #0000ff;">typeof</span><span style="color: #000000;">(Demo08Gallery)); </span><span style="color: #0000ff;">break</span><span style="color: #000000;">; </span><span style="color: #0000ff;">case</span> <span style="color: #800080;">9</span><span style="color: #000000;">: StartActivity(</span><span style="color: #0000ff;">typeof</span><span style="color: #000000;">(Demo09SeekBar)); </span><span style="color: #0000ff;">break</span><span style="color: #000000;">; } }; } } }</span></listview>
Only one piece of content is added to this file: setting a common theme that applies to all pages.
<span style="color: #0000ff;"></span><span style="color: #ff00ff;">xml version="1.0" encoding="utf-8"</span><span style="color: #0000ff;">?></span> <span style="color: #0000ff;"><span style="color: #800000;">manifest </span><span style="color: #ff0000;">xmlns:android</span><span style="color: #0000ff;">="http://schemas.android.com/apk/res/android"</span><span style="color: #ff0000;"> package</span><span style="color: #0000ff;">="ch05demos.ch05demos"</span><span style="color: #ff0000;"> android:versionCode</span><span style="color: #0000ff;">="1"</span><span style="color: #ff0000;"> android:versionName</span><span style="color: #0000ff;">="1.0"</span><span style="color: #0000ff;">></span> <span style="color: #0000ff;"><span style="color: #800000;">uses-sdk </span><span style="color: #0000ff;">/></span> <span style="color: #0000ff;"><span style="color: #800000;">application </span><span style="color: #ff0000;">android:label</span><span style="color: #0000ff;">="ch05demos"</span><span style="color: #ff0000;"> android:theme</span><span style="color: #0000ff;">="@android:style/Theme.DeviceDefault.Light"</span><span style="color: #0000ff;">></span> <span style="color: #0000ff;"></span><span style="color: #800000;">application</span><span style="color: #0000ff;">></span> <span style="color: #0000ff;"></span><span style="color: #800000;">manifest</span><span style="color: #0000ff;">></span></span></span></span>
Starting from the next section, we will introduce how to implement each example and the related concepts involved in these examples.