标签:android
《Android GridView子元素按击交互设计:背景颜色改变》
效果图:
大致的需求和ListView相仿,就是要求用户点击GridView中的子元素时候,要有一定的交互响应(背景颜色改变表明用户的操作)。重点是在GridView的适配器中,子元素的布局文件中,把android:background属性配置成一个响应的selector,在selector中分别处理android:state_pressed事件在true和false两种状态下的情况。
首先写一个MainActivity:
package zhangphil.bg_change; import java.util.ArrayList; import java.util.HashMap; import android.support.v7.app.ActionBarActivity; import android.content.Context; import android.os.Bundle; import android.view.View; import android.widget.AdapterView; import android.widget.AdapterView.OnItemClickListener; import android.widget.GridView; import android.widget.SimpleAdapter; import android.widget.Toast; public class MainActivity extends ActionBarActivity { private final String IMAGE_TAG = "image", TEXT_TAG = "text"; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); GridView gridview = (GridView) findViewById(R.id.gridview); // 数据集 ArrayList<HashMap<String, Object>> data = new ArrayList<HashMap<String, Object>>(); for (int i = 0; i < 19; i++) { HashMap<String, Object> map = new HashMap<String, Object>(); map.put(IMAGE_TAG, R.drawable.ic_launcher); map.put(TEXT_TAG, String.valueOf(i)); data.add(map); } SimpleAdapter adapter = new SimpleAdapter(this, data, R.layout.item, new String[] { IMAGE_TAG, TEXT_TAG }, new int[] { R.id.image, R.id.text }); gridview.setAdapter(adapter); // 添加点击事件 final Context context = this; gridview.setOnItemClickListener(new OnItemClickListener() { public void onItemClick(AdapterView<?> parent, View v, int position, long id) { Toast.makeText(context, String.valueOf(position), Toast.LENGTH_SHORT).show(); } }); } }
MainActivity需要的布局文件activity_main.xml:
<?xml version="1.0" encoding="utf-8"?> <GridView xmlns:android="http://schemas.android.com/apk/res/android" android:id="@+id/gridview" android:layout_width="match_parent" android:layout_height="match_parent" android:padding="10dip" android:numColumns="auto_fit" android:verticalSpacing="10dip" android:horizontalSpacing="10dip" android:stretchMode="columnWidth" />
在为GridView添加子元素时候,数据集中需要的item.xml,该XML文件中的item_selector将对交互时间做出响应(用户长按、点击的背景颜色改变):
<?xml version="1.0" encoding="utf-8"?> <FrameLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" > <LinearLayout android:layout_width="match_parent" android:layout_height="wrap_content" android:gravity="center" android:orientation="vertical" > <ImageView android:id="@+id/image" android:layout_width="wrap_content" android:layout_height="wrap_content" android:src="@drawable/ic_launcher" /> <TextView android:id="@+id/text" android:layout_width="wrap_content" android:layout_height="wrap_content" /> </LinearLayout> <View android:layout_width="match_parent" android:layout_height="match_parent" android:background="@drawable/item_selector" /> </FrameLayout>
item_selector.xml:
<?xml version="1.0" encoding="utf-8"?> <selector xmlns:android="http://schemas.android.com/apk/res/android"> <item android:drawable="@drawable/item_pressed" android:state_pressed="true"/> <item android:drawable="@drawable/item_normal" android:state_pressed="false"/> </selector>
item_selector需要的两个文件item_normal.xml 和 item_pressed.xml:
item_normal
<?xml version="1.0" encoding="utf-8"?> <shape xmlns:android="http://schemas.android.com/apk/res/android" > <solid android:color="#00000000" /> <corners android:radius="5dp" /> <stroke android:width="1px" android:color="#CCCCCC" /> </shape>
item_pressed
<?xml version="1.0" encoding="utf-8"?> <shape xmlns:android="http://schemas.android.com/apk/res/android" > <solid android:color="#5501D1FF" /> <corners android:radius="5dp" /> <stroke android:width="1px" android:color="#CCCCCC" /> </shape>
Android GridView子元素item按击交互设计:背景颜色改变
标签:android
原文地址:http://blog.csdn.net/zhangphil/article/details/46048583