自定義ListView子專案佈局
阿新 • • 發佈：2019-01-31
之前學習的ListView都是採用android系統自帶的子專案佈局，比如android.R.layout.simple_list_item_1（單行文字），以及android.R.layout.simple_list_item_2(雙行文字)
但是實際軟體開發中我們更希望ListView的子專案的佈局更加豐富，不僅有文字還有圖片，圖示之類的。當然位置也可以自定義了。下面我就來接受下怎麼製作一個自定義的ListView的Item佈局並通過BaseAdpater繫結 顯示。
當然首先你需要設計一個輸入自己ListView選項Item的佈局：比如我設計的就是下面這樣
每個ListView選項包括一個頭像ImageView, 姓名TextView,動態Dynamic，以及一個檢視Button。點選檢視Button的時候會在最頂部的兩個TextView中顯示點選選項的姓名和動態文字。效果如下面所示:
下面是選項佈局檔案holderlistviw.xml中的程式碼:
注意:之所在Button中巢狀一個LinearLayout是為了讓按鈕靠最右邊.這就是在建立專案中檢視按鈕的OnClickListener的時候，為了獲得選項中的名字和動態，需要先獲得選項的View。這時候需要把程式碼攜程View myView = (View)checkButton.getParent().getParent().因為嵌套了兩個LinearLayout佈局，這個一定要注意，如果攜程View myView = (View)checkButton.getParent()會引起程式崩潰。<span style="font-size:14px;"><?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="120dp" android:orientation="horizontal" > <ImageView android:id="@+id/image" android:layout_width="wrap_content" android:layout_height="match_parent" /> <LinearLayout android:layout_width="wrap_content" android:layout_height="match_parent" android:layout_marginLeft="5dp" android:orientation="vertical" > <TextView android:id="@+id/name" android:layout_width="wrap_content" android:layout_height="50dp" android:textSize="20sp" /> <TextView android:id="@+id/dynamic" android:layout_width="wrap_content" android:layout_height="60dp" android:layout_marginTop="10dp" android:textSize="25sp" /> </LinearLayout> <LinearLayout android:gravity="right" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="horizontal" > <Button android:layout_alignParentRight="true" android:layout_width="40dp" android:layout_height="match_parent" android:text="查 看" android:id="@+id/check" android:textSize="20sp" android:layout_gravity="right" /> </LinearLayout> </LinearLayout></span>
接著要建立一個自定義的ListViewAdapter，繼承BaseAdapter，重寫getCount()和getView（）方法。對應的ListViewAdapter.java中程式碼如下:
<span style="font-size:14px;">package com.example.fileoperator;
import java.util.List;
import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.TextView;
public class ListViewAdapter extends BaseAdapter {
private List<String> name = null;
private List<String> dynamic = null;
private int[] imageId = null;
private LayoutInflater myLayoutInflater = null;
private Context context = null;
private Button.OnClickListener myButtonListener = null;
private static class ViewHolder{//建立一個內部類ViewHolder，設定選項佈局中的元素
public ImageView imageView = null;
public TextView nameTextView = null;
public TextView dynamicTextView = null;
public Button checkButton = null;
}
public void setItemCheckButtonListener(Button.OnClickListener myButtonListener){
this.myButtonListener = myButtonListener;
}
public ListViewAdapter(List<String> name, List<String> dynamic,
int[] imageId, Context context) { //傳入Adapter的引數，並建立Adapter
this.context = context;
this.name = name;
this.dynamic = dynamic;
this.imageId = imageId;
this.myLayoutInflater = LayoutInflater.from(context);
}
@Override
public int getCount() {
int count = 0;
if(imageId==null||name==null|dynamic==null){
return count;
}else
return name.size();
}
@Override
public Object getItem(int position) {
return position;
}
@Override
public long getItemId(int position) {
return position;
}
@Override
public View getView(int position, View view, ViewGroup viewGroup) {
ViewHolder holder = null;
if(view == null){
holder = new ViewHolder();
view = myLayoutInflater.inflate(R.layout.holderviewlayout, null);
holder.imageView = (ImageView)view.findViewById(R.id.image);
holder.nameTextView = (TextView)view.findViewById(R.id.name);
holder.dynamicTextView = (TextView)view.findViewById(R.id.dynamic);
holder.checkButton = (Button)view.findViewById(R.id.check);
view.setTag(holder);
}else{
holder = (ViewHolder) view.getTag();
}
holder.imageView.setImageResource(imageId[position]);
holder.nameTextView.setText(name.get(position).toString());
holder.dynamicTextView.setText(dynamic.get(position));
holder.checkButton.setOnClickListener(myButtonListener);
return view;
}
}
</span>這裡的ViewHolder是一個內部類，用它來載入佈局中的元素，然後改變元素的屬性。
最後用一個ListActivity實現最終效果，主程式ListViewActivity.java檔案中程式碼:
<span style="font-size:14px;">package com.example.fileoperator;
import java.util.ArrayList;
import java.util.List;
import android.app.ListActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.ListView;
import android.widget.TextView;
public class ListViewActivity extends ListActivity{
private TextView textView1 = null;
private TextView textView2 = null;
private String[] myStringArr;
private String[] myDaynamic;
private ListView myListView = null;
private int[] imageId={R.drawable.image1,R.drawable.image2,R.drawable.image3,
R.drawable.image4,R.drawable.image5,R.drawable.image6,R.drawable.image7,
R.drawable.image8,R.drawable.image9};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
myStringArr = getResources().getStringArray(R.array.myarrayname);
myDaynamic = getResources().getStringArray(R.array.dynamic);
textView1 = (TextView)this.findViewById(R.id.mytextview1);
textView2 = (TextView)this.findViewById(R.id.mytextview);
List<String> name = new ArrayList<String>();
List<String> dynamic = new ArrayList<String>();
for(int i=0;i<myStringArr.length;i++){
name.add(myStringArr[i]);
dynamic.add(myDaynamic[i]);
}
ListViewAdapter myAdatper = new ListViewAdapter(name,dynamic,imageId,this);
myAdatper.setItemCheckButtonListener(myButtonListener);
myListView = getListView();
myListView.setAdapter(myAdatper);
}
private Button.OnClickListener myButtonListener = new Button.OnClickListener() {
@Override
public void onClick(View view) {
<span style="color:#ff0000;">View myItemView = (View) view.getParent().getParent();//注意！</span>
String name = ((TextView)myItemView.findViewById(R.id.name)).getText().toString();
String dynamic = ((TextView)myItemView.findViewById(R.id.dynamic)).getText().toString();
textView1.setText(name);
textView2.setText(dynamic);
}
};
}
</span>By the Way，主程式中用到了兩個string-array資源，他們定義在res/values/strings.xml中，具體程式碼如下:
<?xml version="1.0" encoding="utf-8"?>
<resources>
<string name="app_name">fileoperator</string>
<string name="hello_world">Hello world!</string>
<string name="action_settings">Settings</string>
<string-array
name = "myarrayname">
<item>yangwan</item>
<item>chenyan</item>
<item>Tom</item>
<item>Jim</item>
<item>Xiaoxiao</item>
<item>Alice</item>
<item>Gerny</item>
<item>Tony</item>
<item>Afusen</item>
</string-array>
<string-array
name = "dynamic">
<item>1.我很強壯</item>
<item>2.我很懶</item>
<item>3.我很開心</item>
<item>4.我很失落</item>
<item>5.我是吃貨</item>
<item>6.我很笨</item>
<item>7.你很堅強</item>
<item>8.你神經</item>
<item>9.我無語</item>
</string-array>
</resources>