Android之shape與selector實現圓角

shape和selector是Android UI設計中經常用到的，比如我們要自訂一個圓角Button，點擊Button有些效果的變化，就要用到shape和selector。可以這樣說，shape和selector在美化控制項中的作用是至關重要的。

1.Shape

簡介

作用：XML中定義的幾何形狀

位置：res/drawable/檔案的名稱.xml

使用的方法：

Java代碼中：R.drawable.檔案的名稱

XML中：android:background="@drawable/檔案的名稱"

屬性：

<shape>  android:shape=["rectangle" | "oval" | "line" | "ring"]其中rectagle矩形，oval橢圓，line水平直線，ring環形<shape>中子節點的常用屬性：<gradient>  漸層android:startColor  起始顏色android:endColor  結束顏色             android:angle  漸層角度，0從上到下，90表示從左至右，數值為45的整數倍預設為0；android:type  漸層的樣式 liner線性漸層 radial環形漸層 sweep<solid >  填充android:color  填充的顏色<stroke > 描邊android:width 描邊的寬度android:color 描邊的顏色android:dashWidth 表示'-'橫線的寬度android:dashGap 表示'-'橫線之間的距離<corners > 圓角android:radius  圓角的半徑 值越大角越圓android:topRightRadius  右上圓角半徑  android:bottomLeftRadius 右下圓角角半徑 android:topLeftRadius 左上圓角半徑android:bottomRightRadius 左下圓角半徑

2.Selector

 簡介

位置：res/drawable/檔案的名稱.xml

使用的方法：

Java代碼中：R.drawable.檔案的名稱

XML中：android:background="@drawable/檔案的名稱"

selector.xml

<?xml version="1.0" encoding="utf-8"?>     <selector xmlns:android="http://schemas.android.com/apk/res/android">              <item android:state_selected="true">             <shape>                 <gradient android:angle="270" android:endColor="#99BD4C"                     android:startColor="#A5D245" />                 <size android:height="60dp" android:width="320dp" />                 <corners android:radius="8dp" />             </shape>         </item>         <item android:state_pressed="true">             <shape>                 <gradient android:angle="270" android:endColor="#99BD4C"                     android:startColor="#A5D245"/>                 <size android:height="60dp" android:width="320dp" />                 <corners android:radius="8dp" />             </shape>         </item>         <item>             <shape>                 <gradient android:angle="270" android:endColor="#A8C3B0"                     android:startColor="#C6CFCE"/>                 <size android:height="60dp" android:width="320dp" />                 <corners android:radius="8dp" />             </shape>         </item>     </selector>

list_item.xml

<?xml version="1.0" encoding="utf-8"?>        <LinearLayout  xmlns:android="http://schemas.android.com/apk/res/android"         android:orientation="horizontal"           android:layout_width="fill_parent"            android:layout_height="wrap_content"         android:background="@drawable/selector"         >                             <ImageView               android:id="@+id/img"                android:layout_width="wrap_content"               android:layout_height="wrap_content"                          android:layout_gravity="center_vertical"             android:layout_marginLeft="20dp"                      />                                        <TextView                   android:text="data"                   android:id="@+id/title"                 android:layout_width="fill_parent"                   android:layout_height="wrap_content"                   android:gravity="center_vertical"                    android:layout_marginLeft="20dp"                   android:layout_marginTop="20dp"                   android:textSize="14sp"                                           android:textStyle="bold"                 android:textColor="@color/black"                                          >             </TextView>                </LinearLayout>

main.xml

<?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="wrap_content"             android:background="#253853"             >                                             <ListView                 android:id="@+id/list"                 android:layout_width="match_parent"                 android:layout_height="match_parent"               android:cacheColorHint="#00000000"               android:divider="#2A4562"               android:dividerHeight="3px"               android:listSelector="#264365"               android:drawSelectorOnTop="false"                >             </ListView>       </LinearLayout>

colors.xml

<?xml version="1.0" encoding="utf-8"?>     <resources>         <color name="white">#FFFFFFFF</color>         <color name="transparency">#00000000</color>         <color name="title_bg">#1C86EE</color>         <color name="end_color">#A0cfef83</color>         <color name="black">#464646</color>     </resources>

MainActivity

package com.lingdududu.customlist;           import java.util.ArrayList;      import java.util.HashMap;           import xb.customlist.R;           import android.R.array;      import android.app.Activity;      import android.os.Bundle;      import android.widget.ArrayAdapter;      import android.widget.ListView;      import android.widget.SimpleAdapter;           public class MainActivity extends Activity {          ListView list;                    String data[] = new String[]{                  "China","UK","USA","Japan","German","Canada","ET","Narotu"            };                                     @Override         public void onCreate(Bundle savedInstanceState) {              super.onCreate(savedInstanceState);              setContentView(R.layout.main);                                          list =(ListView) findViewById(R.id.list);                                    SimpleAdapter adapter = new SimpleAdapter(this, getData(), R.layout.list_item,                       new String[]{"title","img"}, new int[]{R.id.title,R.id.img});                            list.setAdapter(adapter);                  }                    private ArrayList<HashMap<String, Object>> getData() {                    ArrayList<HashMap<String, Object>> dlist = new ArrayList<HashMap<String,Object>>();                            for(int i =0;i<data.length;i++){                  HashMap<String, Object>map = new HashMap<String, Object>();                           map.put("title", data[i]);                  map.put("img", R.drawable.item_left2);                  dlist.add(map);               }              return dlist;          }      }

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