二級橫向listview

一、介紹
二級橫向串列本質是在一級串列的點擊事件中新增一個串列，只要提前在布局檔案中布置兩個listview控制元件

二、簡單介紹代碼
activity_main.xml 檔案 button控制元件的作用是用來動態生成首級的listview內容

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context=".MainActivity">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_weight="3">
<ListView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/listview1"
android:layout_weight="1"
android:choiceMode="singleChoice"
android:focusableInTouchMode="true"
android:focusable="true"/>

<ListView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/listview2"
android:layout_weight="1"
android:choiceMode="singleChoice"
android:focusableInTouchMode="true"
android:focusable="true"/>
</LinearLayout>

<Button
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="@+id/bt1"
android:onClick="onClick"
android:text="bt1"/>
<Button
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="@+id/bt2"
android:onClick="onClick"
android:text="bt2"/>


</LinearLayout>

選項xml檔案 itemlayout.xml

選項類變數 mediaitem.java

重寫listview

package com.testhorlistview;

import android.content.Context;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.widget.ListView;

public class myListView extends ListView{
private float mLastDownY = 0f;
private int mDistance = 0;
private int mStep = 10;
private boolean mPositive = false;


public myListView(Context context) {
super(context);
}

public myListView(Context context, AttributeSet attrs) {
super(context, attrs);
}

public myListView(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
}
}

重寫首級adapter

package com.testhorlistview;

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.TextView;

import java.util.ConcurrentModificationException;
import java.util.List;

public class myAdapter extends BaseAdapter {
Context context;
List<mediaItem> item;

public myAdapter(Context context, List<mediaItem> item){
this.context = context;
this.item = item;
}

@Override
public int getCount() {
return item.size();
}

@Override
public Object getItem(int position) {
return item.get(position);
}

@Override
public long getItemId(int position) {
return position;
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {
convertView = LayoutInflater.from(context).inflate(R.layout.itemlayout,null);
TextView tv = convertView.findViewById(R.id.itemTextView);
tv.setText(item.get(position).getName());
return convertView;
}
}

重寫subAdapter

package com.testhorlistview;

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.TextView;

import org.w3c.dom.Text;

import java.util.ArrayList;
import java.util.ConcurrentModificationException;
import java.util.List;

public class mySubAdapter extends BaseAdapter {

private Context context;
private List<mediaItem> item;

public mySubAdapter(List<mediaItem> item, Context context){
this.item = item;
this.context = context;
}

@Override
public int getCount() {
return item.size();
}

@Override
public Object getItem(int position) {
return item.get(position);
}

@Override
public long getItemId(int position) {
return position;
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {
convertView = LayoutInflater.from(context).inflate(R.layout.itemlayout,null);
TextView tv = convertView.findViewById(R.id.itemTextView);
tv.setText(item.get(position).getName());
return convertView;
}
}

mainactivity

package com.testhorlistview;

import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;

import android.annotation.SuppressLint;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ListView;
import android.widget.Toast;

import java.util.ArrayList;
import java.util.List;

public class MainActivity extends AppCompatActivity {

public ListView lv1;
public ListView lv2;
public myAdapter myadapter;
public mySubAdapter mysubadapter;
public List<mediaItem> list1;
public List<mediaItem> list2;
String name = "選單";
String addr = "地址";

Handler handler = new Handler(){
@SuppressLint("HandlerLeak")
@Override
public void handleMessage(@NonNull Message msg) {
switch (msg.what){
case 1:
myadapter.notifyDataSetChanged();
// lv1.setAdapter(myadapter);
break;
case 2:
break;
}
super.handleMessage(msg);
}
};

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

lv1 = findViewById(R.id.listview1);


list1 = new ArrayList<>();
list2 = new ArrayList<>();
myadapter = new myAdapter(this,list1);
// mysubadapter = new mySubAdapter(list2,this);

lv1.setAdapter(myadapter);
lv2 = findViewById(R.id.listview2);
mysubadapter = new mySubAdapter(list2,getApplicationContext());
lv2.setAdapter(mysubadapter);
lv1.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
list2.clear();
for(int i = 0; i < 4; i++){
list2.add(new mediaItem(name+position+i,name+position+i));
}
new Handler().postDelayed(new Runnable() {
@Override
public void run() {
//mysubadapter.notifyDataSetChanged();
lv2.setAdapter(mysubadapter);
}
},1000);

lv2.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
Toast.makeText(MainActivity.this,"name: "+list2.get(position).getName(),Toast.LENGTH_LONG).show();
}
});
}
});

}
public void onClick(View view) {
switch (view.getId()){
case R.id.bt1:
for(int i = 0; i < 5; i++){
list1.add(new mediaItem(name+i,addr+i));
}
Message msg = new Message();
msg.what =1;
handler.sendMessage(msg);

break;
case R.id.bt2:
break;
}
}
}