Android学习笔记⑧——UI组件的学习AdapterView相关2

前面都是用ListView控件来配合Adapter做的一些实例，这次我们来见识一下GridView与Adapter之间的爱恨情仇。。。。

GridView是用于在界面上按行、列分布的方式来显示多个的组件，与ListView相似，但是比ListView高级，因为他可以一下子有多个列，而ListView只有一列。

GridView设置一个简单的图片浏览器

大概功能就是 点击一下图片，然后下方显示放大的图。。。

主布局代码：

<?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">

    <GridView
        android:id="@+id/gridview"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:gravity="center"
        android:horizontalSpacing="1pt"
        android:numColumns="4"
        android:verticalSpacing="1pt">
    </GridView>

    <ImageView
        android:id="@+id/imageshow"
        android:layout_width="250dp"
        android:layout_height="250dp"
        android:layout_gravity="center_horizontal"
        />
</LinearLayout>

 用与ImageView布局的 代码：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content">

    <ImageView
        android:id="@+id/image"
        android:layout_width="70dp"
        android:layout_height="70dp"
        android:layout_margin="5dp"
        android:scaleType="fitXY"
        />
</LinearLayout>

 

java代码：

package com.doliao.helloworld;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.GridView;
import android.widget.ImageView;
import android.widget.SimpleAdapter;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

/**
 * Created by Administrator on 2016/10/12 0012.
 */

public class GridViewActivity extends Activity {

    GridView gridView;
    ImageView imageView;
    int[] imageids = new int[]{R.drawable.pic1, R.drawable.pic2, R.drawable.pic3, R.drawable.pic4, R.drawable.pic5, R.drawable.pic6
            , R.drawable.pic7, R.drawable.pic8, R.drawable.pic9, R.drawable.pic10, R.drawable.pic11, R.drawable.pic12};

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_gridview);

        gridView = (GridView) findViewById(R.id.gridview);
        imageView = (ImageView) findViewById(R.id.imageshow);

        List<Map<String, Object>> list = new ArrayList<Map<String, Object>>();
        for (int imageid : imageids) {
            Map<String, Object> map = new HashMap<String, Object>();
            map.put("imageid", imageid);
            list.add(map);
        }
        SimpleAdapter simpleAdapter = new SimpleAdapter(this, list, R.layout.all_images,
                new String[]{"imageid"}, new int[]{R.id.image});
        gridView.setAdapter(simpleAdapter);

        gridView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                imageView.setImageResource(imageids[position]);
            }
        });
    }
}

 

运行的显示截图如下：

 

 ExpandableListView (可展开的列表组件)

 ExpandableListView是List的子类，在基本的List上面进行了扩展，他把列表分为几组，每组里面又可以包含多个列表现。简单的来说就相当于QQ列表一样，有分组，分组里面又有好多的好友列表。这么高级的组件本身也是傲娇的，他有自己御用的Adapter——ExpandableListAdapter。EXpandableAdapter与Adapter相似，一般实现的方法有三种：

1、扩展BaseExpandableLIstAdapter实现的ExpandableListAdapter；

2、使用SimpleExpandableListAdapter将两个list集合包装成ExpandableListAdapter

3、使用SimpleCursorTreeAdapter将Cursor中的数据包装成SimpleCursorTreeAdapter。

布局代码：activity_expandablelistview.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical" android:layout_width="match_parent"
    android:layout_height="match_parent">

    <ExpandableListView
        android:id="@+id/expand"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content">

    </ExpandableListView>
</LinearLayout>

 Java代码： ExpandableListViewActivity.java

package com.doliao.helloworld;

import android.app.Activity;
import android.os.Bundle;
import android.view.Gravity;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AbsListView;
import android.widget.BaseExpandableListAdapter;
import android.widget.ExpandableListAdapter;
import android.widget.ExpandableListView;
import android.widget.LinearLayout;
import android.widget.TextView;

/**
 * Created by Administrator on 2016/10/13 0013.
 */


public class ExpandableListViewActivity extends Activity {

    //定义列表组
    String[] listType = new String[]{"名著列表", "小说列表", "动漫列表"};
    //每个列表组下面的数据
    String[][] lists = new String[][]{
            {"西游记", "水浒传", "红楼梦"},
            {"择天记", "星辰变", "间客"},
            {"海贼王", "火影忍者", "死神"}
    };


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_expandablelistview);


        ExpandableListAdapter expandableListAdapter = new BaseExpandableListAdapter() {

            @Override
            public int getGroupCount() {
                return lists.length;
            }

            @Override
            public int getChildrenCount(int groupPosition) {
                return lists[groupPosition].length;
            }

            @Override
            public Object getGroup(int groupPosition) {
                return listType[groupPosition];
            }

            @Override
            public Object getChild(int groupPosition, int childPosition) {
                return lists[groupPosition][childPosition];
            }

            @Override
            public long getGroupId(int groupPosition) {
                return groupPosition;
            }

            @Override
            public long getChildId(int groupPosition, int childPosition) {
                return childPosition;
            }

            @Override
            public boolean hasStableIds() {
                return true;
            }

            @Override
            public View getGroupView(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent) {

                //View view = View.inflate(ExpandableListViewActivity.this, R.layout.autotext, null);
                //TextView textView = (TextView) findViewById(R.layout.autotext);

                /*View view = View.inflate(ExpandableListViewActivity.this, R.layout.linear_text, null);
                TextView textView = (TextView) findViewById(R.id.text1);
                textView.setText(getGroup(groupPosition).toString());
                view.setLayoutParams();*/

                LinearLayout ll = new LinearLayout(ExpandableListViewActivity.this);
                TextView textView = getTextView();
                textView.setText(getGroup(groupPosition).toString());
                ll.addView(textView);
                return ll;

            }

            @Override
            public View getChildView(int groupPosition, int childPosition, boolean isLastChild, View convertView, ViewGroup parent) {
                //TextView textView = (TextView) findViewById(R.id.autotext);
                //textView.setText(getChild(groupPosition, childPosition).toString());
                TextView textView = getTextView();
                textView.setText(getChild(groupPosition, childPosition).toString());
                return textView;
            }

            @Override
            public boolean isChildSelectable(int groupPosition, int childPosition) {
                return true;
            }
        };


        ExpandableListView expandableListView = (ExpandableListView) findViewById(R.id.expand);
        expandableListView.setAdapter(expandableListAdapter);
    }

    private TextView getTextView() {
        AbsListView.LayoutParams lp = new AbsListView.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, 64);
        TextView textView = new TextView(ExpandableListViewActivity.this);
        textView.setLayoutParams(lp);
        textView.setGravity(Gravity.CENTER_VERTICAL | Gravity.LEFT);
        textView.setPadding(36, 0, 0, 0);
        textView.setTextSize(20);
        return textView;
    }
}

 

运行截图：(没有改变颜色。。。)

做这个实例的时候，书上的例子是上面的代码，我一开始是想不用书上的例子，我的想法是他既然是 布局、组件都是新建，那么我应该可以事先设置好他的xml文件，等到时候用的时候，我在调用过来，但是我折腾了好久都没成功，但是我学到了怎么获取 事先布局好的Layout，但是我就不知道如何想Layout中添加组件如下：

View view = View.inflate(ExpandableListViewActivity.this, R.layout.linear_text, null);
TextView textView = (TextView) findViewById(R.id.text1);

布局是事先设置好的，textview独立xml文件或者放在Layout xml的文件中都是行不通的，可能是我想的有问题吧，有可能根本就没这个方法。

最后我放弃了，还是按照书上的例子做了下去，好气啊。先做个标记，容我去打怪升级，等我等级高了再来报仇！！！！！！！！！！！

 

最近工作上面的事情比较忙，所以没有多少时间学习，但是。。。。。。。。还是要坚持主动的学习下去！！！！

如果有错，请大牛们指正。 再次先谢谢了 ！